Simplifying complex interventions: A unique approach to informing implementation strategies
Background: Multiple factors are thought to impact the natural course of low back pain. Thus, international guidelines recommend the use of complex interventions that consist of multiple components that target multiple risk factors. In response, clinicians and researchers have devised a vast collection of complex interventions by combining simple targeted treatments. These complex interventions typically involve interacting components that are often delivered by multidisciplinary teams. For example, a broad lifestyle intervention that targets diet, physical activity, and smoking – delivered via independent government health programs is one example of a complex intervention that aims to address multiple risk factors for back pain. Although targeting multiple risk factors via complex interventions may confer additional patient benefit over simple interventions (e.g. paracetamol), they introduce challenges to clinical application and implementation. The interaction between competing theories, delivery techniques, and behavioural adaptation brings added difficulty and uncertainty when implementing complex interventions. With finite government dollars for healthcare and scarce resources, it is often challenging to successfully implement a complex intervention as originally designed. Under these circumstances, a key challenge is to refine and down-scale complex interventions so that they are implementable, without sacrificing efficacy.
Idea: The idea for this session is to introduce novel approaches to inform how we can simplify complex interventions. Perhaps one efficient approach might be to identify essential mechanisms by which complex interventions exert their effects on patient relevant outcomes. This could potentially guide the removal of excessive and inert components of complex interventions that do not act on essential mechanisms. This process could produce more compact and implementable interventions while retaining essential components of the original intervention. During the first 5-minutes, I will illustrate the practical challenges in implementing complex interventions in clinical practice. I will also highlight why government organisations and policy makers demand simpler forms of complex interventions. For the remaining 15-minutes, I will introduce contemporary methods grounded in causal inference that could guide the adaptation of complex interventions. This will involve causal mechanistic evaluations of clinical trials; with comparison to more established but arguably less efficient designs, such as factorial trials. I will discuss the trade-off between efficiency and rigour, and highlighting the strengths and limitations of each approach. I will illustrate how these approaches can simplify complex interventions by sharing recent examples within and outside the field of back pain.
Potential impact: This proposed session will allow clinicians, researchers, and policy makers to have informed discussions about simplifying complex interventions. Furthermore, this session could develop new initiatives and research directions to simplify complex interventions for efficient implementation. It is undeniable and inevitable that complex interventions are difficult to implement. But with limited health resources, their implementation needs to be simplified. This session proposes new ways of achieving this purpose to inform evidence-based practice and policy decisions for better management of back pain.
Is musculoskeletal pain part of the public health picture in children?
Background: Research efforts into understanding back and neck pain in children and adolescents lags far behind that in adults. This is despite evidence that shows high prevalence and substantial impact on young people’s lives. By comparison, there is substantial popular concern about general health risk factors in childhood such as overweight/obesity, low levels of physical activity, poor mental health, and alcohol and substance use. These issues are recognised for their negative influence during adolescence, as well as their implications for long-term health. These risk factors are the subjects of intensive research efforts and public health campaigns aimed at mitigating their current and future impacts on health. We know that children with pain are more likely report these other indicators of poor health. At this point it is not clear whether causal relationships run in one direction or the other, but as in adults it does appear that poorer overall health is associated with poor prognosis in children with back or neck pain. In the research and clinical spheres, back and neck pain, and generic adverse health risks and behaviours are generally considered separately. Changing this siloed approach offers several potential advantages: more integrated care for paediatric patients with pain; improved understanding of the pathophysiology of back and neck pain; increased exposure for musculoskeletal pain through the link with higher profile health conditions. Adequate response to spinal pain, and lifestyle-related risk factors in adolescence is important, both appear to track into adulthood which means effective prevention is only possible early on in life.
Objective: Explore the place of paediatric back and neck pain in the context of a broader view of health, and consider the implications of this for research and clinical practice.
Target audience: Clinicians and researchers in clinical and public health.
Format: Two presentations followed by a facilitated group discussion.
Presentation 1: Evidence based review of back and neck pain in children and adolescents
Presentation 2: Relationships between pain and adverse health risk factors in children
Discussion: Topic 1) How can clinicians and researchers working with paediatric populations with pain incorporate a broader view of health into their work? Topic 2) How can back and neck pain be addressed in public health campaigns in children? (if time)
Desired outcomes: Bring attendees up to date with current evidence regarding the burden of back and neck pain in children and adolescents, and the links between pain and other risk factors for poor health. Discuss the opportunities and challenges arising from viewing pain in the broader context of childhood health. Establish collaborations between workshop attendees with an interest in addressing back and neck pain in paediatric populations.
Lifestyle-related health risks and low back pain: potential for impact but where to next?
Background: Chronic health conditions such as low back pain (LBP), cardiovascular disease and diabetes have common lifestyle-related risk factors such as diet/overweight/obesity, low levels of physical activity, poor mental health, poor sleep, smoking and alcohol (mis)use. Systematic reviews have shown clear links between these lifestyle factors and LBP. Consequently, LBP is increasingly being recognised as part of a constellation of health risk factors and chronic diseases. Despite these links, research typically addresses LBP independent from other chronic health conditions or lifestyle risk factors. This oversimplification has a number of implications. First, our understanding of the interactions between LBP, lifestyle risk factors and chronic disease states is not well developed. It is unclear, for example, whether lifestyle risk factors are risk factors for LBP, prognostics factors, if LBP contributes to poorer prognosis for lifestyle and chronic disease, or if they share a common disease mechanism. There are also evidence gaps relating to management. Systematic reviews have identified very few studies of lifestyle management approaches for LBP. It is perhaps unsurprising then that the majority of LBP patients who present with risk factors for poor overall health, seldom receive care that integrates the management LBP and associated lifestyle factors. Understanding how lifestyle risk factors and chronic disease interact with LBP is likely to be an important component of successful treatment. Further, targeting broader health factors in the context of LBP care may well lead to a greater impact on overall health. There is strong evidence supporting interventions that target healthy lifestyle in the general population, so there may be scope to focus research efforts on improving their use and application to patients with LBP. In this workshop session, we aim to outline the evidence and evidence gaps and discuss a framework for research, practice, and implementation of integrated care for LBP and lifestyle factors and disease.
Target audience: Researchers, and clinicians, concerned with LBP and lifestyle factors, and who are interested in developing or applying management in the broader context of public health issues.
Format: Two brief presentations followed by a facilitated group discussion.
Presentation 1: Evidence-based review of the relationships between pain and adverse health risk factors (lifestyle factors) and LBP
Presentation 2: Current models of integrated care in LBP
Discussion: A facilitated discussion of two main topics will be centred on ‘where to next for more integrative management of LBP and healthy lifestyle’? Topic 1) Research: what are the necessary questions? Who do we need to work with? What are the logistical challenges? Topic 2) Practice: what would a model of care look like? What are the logistical challenges? Who needs to be involved?Desired outcomes: To present the current
Desired outcomes: To present the current evidence based regarding the links between LBP and other adverse health risk indicators and identify evidence gaps. Discuss the opportunities, challenges and directions of managing LBP in the broader context of health. Establish collaborations between workshop attendees with an interest in addressing LBP in a broader context.
Acceptance of telephone-based weight management and healthy lifestyle intervention among patients with low back and neck pain
Background: Systematic reviews show musculoskeletal conditions including low back pain and neck pain (spinal pain) are associated with lifestyle risk factors for chronic disease and many patients present to care with comorbid health issues. For example, among patients referred to tertiary outpatient clinics for spinal pain, it is estimated that up to 70% of patient are also overweight or obese. Unfortunately, many of these patients report they have not previously been provided advice or support to address their weight. A common reported barrier to the provision of such care is whether patients are accepting of weight loss as a management approach for spinal pain and how they should be provided with this type of care. This study aimed to 1) assess the preferences of patients with spinal pain for accessing weight loss support including the behavioural determinants of weight, diet and exercise, and to 2) assess the acceptance of referral to an existing telephone-based weight management and healthy lifestyle program.
Methods: This study uses data from a longitudinal cohort of patients referred for orthopaedic consultation at a tertiary referral hospital with back, neck, knee, hip or hand/wrist pain. We included items in the baseline survey and 12 month follow up to assess 1) patients’ preferences for accessing support to address lifestyle factors related to their pain (baseline), 2) the acceptability of referral to existing services targeting lifestyle factors, prior to attendance at the outpatient clinic (baseline) and 3) the acceptance of a proactive referral to an existing telephone-based weight management and healthy lifestyle program (12 month follow-up). This presentation will report on the results for patients with spinal pain.
Results: 344 patients with spinal pain completed the baseline survey. Telephone support was the preferred mode for accessing weight loss support (40%) and the majority of patients (61%) considered it acceptable for the health service to refer them to a telephone-based weight management and healthy lifestyle program while waiting for orthopaedic consultation. At 12-month follow-up 385 patients with spinal pain completed the survey, of which 81% accepted referral and agreed to participate in a telephone-based weight management and healthy lifestyle program.
Discussion and conclusions: Patients show a preference for telephone-based support and patient acceptability and acceptance for referral of a telephone-based intervention is high. This finding suggesting that telephone-based care is a potential model of care delivery to the many patients with musculoskeletal conditions.
Clinimetric Testing of the Lumbar Spinal Instability Questionnaire
Background: The LSIQ is a 15-item self-reported measure purported to measure instability. A comprehensive evaluation of the questionnaire as a measure is required before the LSIQ can be recommended. The aim of this study was to evaluate the measurement properties of the LSIQ in sample of patients with non-specific LBP.
Methods: We considered people with nonspecific LBP presenting to primary care. Rasch analysis was conducted to assess item hierarchy, targeting, unidimensionality, person fit, internal consistency and differential item functioning. We also tested test-retest reliability for total scores and each item and convergent and divergent validity with the PainDetect Questionnaire (PD-Q).
Results: We included 107 participants with chronic LBP (mean age [SD]: 49.5 [16.6] years). The LSIQ appeared to constitute a unidimensional measure, targeted the sample well and showed adequate test-retest reliability. However, the scale had poor internal consistency, did not appear to function as an interval-level measure and lacked strong evidence of construct validity (moderate correlation with PD-Q). Although no items appeared to be redundant, several items were biased by factors other than the proposed construct of the measure.
Discussion and conclusions: We suggest a theoretical reconsideration of the LSIQ. Although it provided satisfactory estimates for some clinimetric features, we cannot consider it as an internal-level measure but rather an index. Future studies are needed to investigate whether the LSIQ measures instability or some other construct.
Is schoolbag use a risk factor for back pain? A systematic review
Background: Previous studies have reported that the musculoskeletal system of children and adolescents can be affected by carrying heavy school bags, resulting in low back pain. However, the evidence on the association between backpack weight, or other characteristics of backpack use, and the risk of back pain is inconclusive. A greater understanding of school bag-related risk factors associated with back pain in children is important to determine whether and what preventative action can be taken, with the aim of controlling and/or reducing back pain among children. The aim of this is study is to investigate whether characteristics of school bag use (e.g., load carried, duration of use, bag design, method of carrying bag, perceived weight) are risk factors for back pain in children and adolescents.
Methods: We searched MEDLINE, EMBASE and CINAHL from inception to April 2016 for prospective cohort studies, cross-sectional studies and randomised controlled trials evaluating the influence of carrying a backpack on non-specific back pain in children and adolescents of school-age. Two reviewers independently extracted the data of an episode of back pain, an episode of care for back pain, all the data associated with backpack (i.e., weight of school bag, load carried, duration of use, bag design, method of carrying bag and perceived weight) and all the characteristic of the included studies. Two reviewers will also independently assess the methodological quality of the included studies using the QUIPS tool.
Results: The searches retrieved 5,755 studies, and after screening titles, abstracts and full text, we included 61 studies. (n=59,772), of which five were prospective studies and 55 cross-sectional or retrospective studies. We found evidence from prospective studies with moderate to high risk of bias, that schoolbag characteristics such as weight, design, and carriage method may not increase the risk of developing BP in children. Evidence from cross-sectional studies was mostly consistent with the findings from prospective studies. Two prospective studies also reported that the perception of heaviness or the difficult to carry the schoolbag were associated with BP and persistent symptoms, respectively.
Discussion and conclusions: There is no convincing evidence that aspects of schoolbag use increase the risk of BP. There is some evidence that the perception of heaviness is associated with risk of future LBP or persistent pain. More studies with optimal methods are needed to investigate the risk factors of BP in this population.
Understanding how patient education improves outcomes for patients with acute low back pain. Causal mediation analysis of the PREVENT trial
Background: Clinical guidelines recommend the use of patient education for the management of acute low back pain. Patient education is a complex intervention that is hypothesised to improve patient-related outcomes via multiple targeted causal mechanisms. The key hypothesised targets are to improve self-efficacy, reduce catastrophisation, and correct erroneous beliefs about back pain. Understanding the underlying mechanisms by which patient education exerts its effect on patient-relevant outcomes (pain, disability) is important for the refinement and adaptation of this intervention.
Purpose: To determine whether the effect of patient education on pain and disability is causally mediated via changes in self-efficacy, catastrophisation, and back pain beliefs.
Methods: We recruited 202 participants with acute low back pain from primary care clinics in Sydney, Australia, who had >30% absolute risk of developing chronic low back pain according to a validated prognostic tool (PICKUP). Participants were randomised to receive either ‘patient education’ or ‘sham education’. For patient education, each session involved discussion of how to self-manage, as well as information about the nature of pain – including the difference between nociception and pain, and the role of the brain in determining how much pain one feels. For sham education, the physiotherapist gathered information and used active listening techniques, but did not provide any advice. Outcomes were pain intensity (Numeric Rating Scale) over the past week and disability (Roland-Morris Disability Questionnaire), which we collected at baseline, 1, and 12 weeks via online questionnaires. The putative mediators, including self-efficacy, catastrophization, and pain beliefs, were collected at baseline and 1 week post-intervention. The protocol for this mediation analysis has been published. Causal mediation analysis will be used to test single and multiple mediator models. Sensitivity analyses will be conducted to evaluate the robustness of the estimated mediation effects on the influence of violating sequential ignorability – a critical assumption for causal inference.
Results: We randomised 202 participants to the patient education (n=101) or sham education (n=101) sessions. Follow-up rates exceeded 95% for all outcomes and mediators at all time-points. The statistical analysis plan is published, and the analysis is due to be completed in April 2017. We will present results of this causal mediation analysis for the first time at the conference.
Discussion and conclusions: This study will estimate the causal mediation effects of patient education for acute low back pain. This knowledge is critical for further development and refinement of this widely used complex intervention.
Do musculoskeletal conditions increase the risk of chronic disease: a systematic review and meta-analysis of longitudinal cohort studies
Background: A growing body of research shows low back pain (LBP), and other musculoskeletal conditions are associated with other chronic diseases such as cardiovascular disease, obesity, diabetes and cancer. A suggested mechanism for this relationship is that LBP contributes to the development of other chronic diseases. For example, pain and disability may limit physical activity and subsequently increase the risk of obesity, cardiovascular disease, diabetes, or cancer. We undertook a systematic review to investigate the causal relationship between common musculoskeletal conditions (low back and neck pain, and osteoarthritis of the hip and knee) and chronic diseases (cardiovascular disease, cancer, diabetes, chronic respiratory disease and obesity).
Methods: We searched relevant databases up to November 2016 and identified longitudinal cohort studies that estimated a temporal association between the prevalence of musculoskeletal conditions (neck or back pain, and osteoarthritis of the hip and knee) at baseline and chronic disease (cardiovascular disease, cancer, diabetes, chronic respiratory disease and obesity) throughout follow up. Risk of bias was assessed using a modified version of the QUIPS tools. We pooled adjusted hazard ratios and incidence rate ratios, using random-effects meta-analyses. We conducted subgroup analyses separated by musculoskeletal conditions and by outcome where possible.
Results: We identified 13,736 articles of which 16 articles reporting on 11 studies met the inclusion criteria. The primary meta-analysis included data from 10 studies and 3,042,539 persons. Cardiovascular disease was the outcome in 9 studies and cancer in 1 study. Two studies measured LBP as the exposure and eight measured osteoarthritis. The primary meta-analysis revealed a statistically significant increase in the risk of developing ‘chronic disease’ in those reporting musculoskeletal conditions at baseline (HR= 1.18; 95% CI, 1.13 to 1.22; I2 57%). Subgroup analysis by condition revealed a similar result for OA and chronic disease. No meta-analysis was performed for LBP. The two studies of LBP found people with LBP had an increased risk of cardiovascular disease (HR=2.13; 95% CI, 1.32 to 3.44) and 10-year incidence of cancer (IRR= 1.25; 95% CI, 1.19 to 1.32).
Discussion and conclusions: Patients with musculoskeletal conditions have an increased risk of subsequent chronic disease. While there is some evidence supporting back pain is a risk for chronic disease few studies have been conducted. Further studies are required to assess the casual relationship between musculoskeletal conditions and chronic diseases. These may assist in the development of preventive strategies and more integrative health care for patients with these comorbid conditions.
The relationship between growth, maturity, and spinal pain in adolescents: a systematic review
Background: Adolescence is a period of life characterised by profound development. The prevalence of spinal pain increases sharply during adolescence, in theory influenced by changes in physical vulnerability associated with rapid growth and development. Individuals of the same chronological age can vary considerably in height, weight and stage of maturation, and these variables may be more likely to directly influence musculoskeletal pain than chronological age of itself. This study aims to determine whether there is a relationship between physical growth and development as determined by markers of biological maturation, and spinal pain in adolescents.
Methods: The protocol for this systematic review was registered a priori through PROSPERO (CRD42014014333). Electronic databases (PubMed, EMBASE and CINAHL) were searched up to 26th October 2016 to identify studies that evaluate the association between biological maturation or growth, and musculoskeletal disorders in adolescents (chronological age 10-19 years). Risk of bias was appraised using the Quality in Prognosis Studies (QUIPS) tool, modified to assess aetiological factors. Associations between growth or maturation, and spinal pain were extracted. Meta-analysis was not possible due to clinical and methodological heterogeneity, so narrative synthesis was conducted.
Results: From 19,117 titles identified in the searches, 476 full-text articles were retrieved and assessed for eligibility; 13 studies that evaluated the relationship between growth and/or maturation, and spinal pain and were included. Study designs were prospective (n=9), cross-sectional (n=3) or case-controlled (n=1). Study outcomes were back pain unspecified (n=5), low back pain (n=7), thoracic pain (n=1) and neck pain (n=3). Measures of growth, and maturation were evaluated as independent factors for spinal pain in seven, and nine studies, respectively. Of these, only one study reported a significant association between high growth rate and low back pain; and eight studies reported that advanced maturation was associated with spinal pain.
Discussion and conclusions: There is a paucity of robust data to support the premise that periods of rapid growth are associated with spinal pain in adolescence. Early, and advanced maturation appears to be associated with spinal pain in adolescence, however there are methodological inconsistencies that preclude a conclusive statement. The body of knowledge is limited by inappropriate study designs, outcome measures with unknown measurement properties, and weaknesses in data collection methods, in particular issues of temporality. Future research is required to clarify the relationship between growth and maturation and spinal pain in adolescents
Adverse health risk indicators in adolescents with back pain
Background: Substance use and psychological distress are causes of concern in adolescents. They are drivers of adverse health and social outcomes proximally and into the future. For this reason they are targets of public health campaigns delivered in schools. Prevalence of back pain rises steeply in adolescence and has significant consequences for many, including: missing school, interference with physical and day-to-day activities, and usage of health care services and medication. Disabling pain in this period of life may also have implications for pain in adulthood. The relationship between back pain and adverse health risk factors remains unclear. There is a question as to whether, or to what extent, pain forms part of a cluster of behaviours and health-related factors indicative of poor health. Resolving this issue will help characterise at-risk youth and facilitate design of improved public health initiatives. The aim of this study was to assess whether adolescents that experience back pain more frequently are also more likely to report adverse health risk behaviours and poorer mental health.
Methods: Analysis of two cross-sectional samples of 14-15 year-olds. One from across Australia (Australian Child Well-being Project, n=3,896), and one from the Newcastle area (Healthy Schools Healthy Futures, n=1,831). All participants were asked how frequently they experienced back pain in the past 6 months: rarely/never, about every month, about every week, more than 1x/week, about every day. They were also asked about smoking, alcohol consumption, missed school, and feelings of depression and anxiety, responses were dichotomised. Participants were stratified by frequency of back pain, and the proportion of positive responses to the behaviours and mental health questions reported for each strata. Test-for-trend analyses were conducted to determine whether experiencing back pain more often was associated with increased adverse health behaviours and feelings of anxiety and depression.
Results: In total, 3.2% and 9.3% of participants had ever drunk alcohol in the two samples, and 4.4% and 12.6% had ever smoked. Although the absolute rates were higher in the Healthy Schools dataset, alcohol consumption and smoking in both samples increased steadily with more frequent back pain. Of those who reported pain about every day; 12.2% and 21.3% had drunk alcohol, and 12.7% and 20.8% had smoked, in the two samples. The proportion of students that missed school regularly was only measured in one dataset, but showed the same pattern of increase with more frequent back pain. The same trend for increased prevalence of feelings of anxiety and depression with increasing back pain frequency was evident, although absolute difference between strata were small.
Discussion and Conclusion: There was the same, consistent relationship between frequency of back pain and adverse health risk indicators in two independently-collected samples of adolescents. These are descriptive data, so unsuitable for attributing causation, but they do indicate that frequent back pain is part of a picture of poor health and adverse health risk. These findings have implications for identifying a population at-risk of poor health, and point to the need to consider more integrated management of adolescents with back pain.
Mechanism evaluation of a lifestyle behavioural intervention for patients with low back pain who are overweight or obese
Background: A large proportion of patients with low back pain are physically inactive, have poor diet, and are overweight or obese. Targeting factors such as diet and physical activity as part of routine management is a plausible strategy to improve outcomes for these patients. A randomised trial has tested the effectiveness of a multi-component lifestyle behavioural intervention for patients with low back pain who are overweight or obese. However, merely evaluating the effectiveness of this complex intervention is insufficient; it is important to understand the underlying causal mechanisms to explain how the intervention worked, or why the intervention failed.
Purpose: To determine whether the effect of a lifestyle intervention on pain and disability is causally mediated via changes in weight, diet, physical activity, and pain beliefs.
Methods: We recruited 160 participants with chronic low back waiting for outpatient orthopaedic consultation at a tertiary referral public hospital in New South Wales, Australia. Participants were randomised to receive a lifestyle behavioural intervention, or to remain part of the original cohort (usual care). The intervention consists of: education and advice about the benefits of weight loss and physical activity, and a telephone-delivered healthy lifestyle program (Get Healthy Service). All outcome measures including patient characteristics, primary and alternative mediators, outcomes, and potential confounders were measured at baseline. The primary mediator: weight, was measured at 6 months’ post-randomisation; alternative mediators including diet, physical activity, and pain beliefs were measured 6 weeks’ postrandomisation. All outcomes: pain, disability, and quality of life, were measured 6 months’ postrandomisation. Data will be analysed using causal mediation analysis with sensitivity analyses to test the assumption of sequential ignorability.
Results: We randomised 160 participants to the behavioural lifestyle intervention (n=80) or usual care (n=80). The statistical analysis plan is accepted for publication, and the analysis is due to be completed in March 2017. We will present results of this causal mediation analysis for the first time at the conference.
Discussion and conclusions: This study will estimate the causal mediation effects of a lifestyle intervention for patients with chronic low back pain. This knowledge is critical for further development and refinement of this complex intervention.
Understanding how pain education causes changes in pain and disability: protocol for a causal mediation analysis of the PREVENT trial
Lee et al. J Physiother. 2015;61(3):156.
Introduction
Pain education is a complex intervention developed to help clinicians manage low back pain. Although complex interventions are usually evaluated by their effects on outcomes, such as pain or disability, most do not directly target these outcomes; instead, they target intermediate factors that are presumed to be associated with the outcomes. The mechanisms underlying treatment effects, or the effect of an intervention on an intermediate factor and its subsequent effect on outcome, are rarely investigated in clinical trials. This leaves a gap in the evidence for understanding how treatments exert their effects on outcomes. Mediation analysis provides a method for identifying and quantifying the mechanisms that underlie interventions.
Aim
To determine whether the effect of pain education on pain and disability is mediated by changes in self-efficacy, catastrophisation and back pain beliefs.
Design
Causal mediation analysis of the PREVENT randomised controlled trial.
Participants and setting
Two hundred and two participants with acute low back pain from primary care clinics in the Sydney metropolitan area.
Intervention
Participants will be randomised to receive either ‘pain education’ (intervention group) or ‘sham education’ (control group).
Measurements
All outcome measures (including patient characteristics), primary outcome measures (pain and disability), and putative mediating variables (self-efficacy, catastrophisation and back pain beliefs) will be measured prior to randomisation. Putative mediators and primary outcome measures will be measured 1 week after the intervention, and primary outcome measures will be measured 3 months after the onset of low back pain.
Analysis
Causal mediation analysis under the potential outcomes framework will be used to test single and multiple mediator models. A sensitivity analysis will be conducted to evaluate the robustness of the estimated mediation effects on the influence of violating sequential ignorability – a critical assumption for causal inference.
Discussion and significance
Mediation analysis of clinical trials can estimate how much the total effect of the treatment on the outcome is carried through an indirect path. Using mediation analysis to understand these mechanisms can generate evidence that can be used to tailor treatments and optimise treatment effects. In this study, the causal mediation effects of a pain education intervention for acute non-specific low back pain will be estimated. This knowledge is critical for further development and refinement of interventions for conditions such as low back pain.
Trial registration: Australian New Zealand Clinical Trials Registry (ACTRN). Registration number: 12612001180808
A randomised controlled trial of a lifestyle behavioural intervention for patients with low back pain, who are overweight or obese: study protocol
Williams et al. BMC Musculoskeletal Disorders. 2016;17:70.
Background: Low back pain is a highly prevalent condition with a significant global burden. Management of lifestyle
factors such as overweight and obesity may improve low back pain patient outcomes. Currently there are no randomised
controlled trials that have been conducted to assess the effectiveness of lifestyle behavioural interventions in managing
low back pain. The aim of this trial is to determine if a telephone-based lifestyle behavioural intervention is effective in
reducing pain intensity in overweight or obese patients with low back pain, compared to usual care.
Methods/Design: A randomised controlled trial will be conducted with patients waiting for an outpatient consultation
with an orthopaedic surgeon at a public tertiary referral hospital within New South Wales, Australia for chronic low back
pain. Patients will be randomly allocated in a 1:1 ratio to receive a lifestyle behavioural intervention (intervention group)
or continue with usual care (control group). After baseline data collection, patients in the intervention group will receive
a clinical consultation followed by a 6-month telephone-based lifestyle behavioural intervention (10 individually tailored
sessions over a 6-month period) and patients in the control group will continue with usual care. Participants will
be followed for 26 weeks and asked to undertake three self-reported questionnaires at baseline (pre-randomisation),
week 6 and 26 post randomisation to collect primary and secondary outcome data. The study requires a sample of 80
participants per group to detect a 1.5 point difference in pain intensity (primary outcome) 26 weeks post randomisation.
The primary outcome, pain intensity, will be measured using a 0–10 numerical rating scale.
Discussion: The study will provide robust evidence regarding the effectiveness of a lifestyle behavioural intervention in
reducing pain intensity in overweight or obese patients with low back pain and inform management of these patients.
Trial registration number: Australian New Zealand Clinical Trials Registry, ACTRN12615000478516, Registered
14/05/2015.
Randomised controlled trial of referral to a telephone-based weight management and healthy lifestyle programme for patients with knee osteoarthritis who are overweight
or obese: a study protocol
O’Brien et al. BMJ Open. 2016;6:e010203.
Introduction: Knee osteoarthritis (OA) is one of the most common chronic diseases worldwide and is associated with significant pain and disability. Clinical practice guidelines consistently recommend weight management as a core aspect of care for overweight and obese patients with knee OA; however, provision of such care is suboptimal. Telephone-based interventions offer a novel approach to delivery of weight management care in these patients. The aim of the proposed study is to assess the effectiveness of referral to a telephone-based weight management and healthy lifestyle programme, previously shown to be effective in changing weight, in improving knee pain intensity in overweight or obese patients with knee OA, compared to usual care.
Methods and analysis: A parallel, randomised controlled trial will be undertaken. Patients with OA of the knee who are waiting for an outpatient orthopaedic consultation at a tertiary referral public hospital within New South Wales, Australia, will be allocated to either an intervention or a control group (1:1 ratio). After baseline data collection, patients in the intervention group will receive a 6-month telephone-based intervention, and patients in the control group will continue with usual care. Surveys will be conducted at baseline, 6 and 26 weeks post-randomisation. The study requires 60 participants per group to detect a two-point difference in pain intensity ( primary outcome) 26 weeks after baseline.
Ethics and dissemination: The study is approved by the Hunter New England Health Human
Research Ethics Committee (13/12/11/5.18) and the University of Newcastle Human Research Ethics Committee (H-2015-0043). The results will be disseminated in peer-reviewed journals and at scientific conferences.
Trial registration number: ACTRN12615000490572, Pre-results.
Effectiveness of a healthy lifestyle intervention for low back pain and osteoarthritis of the knee: protocol and statistical analysis plan for two randomised controlled trials
O’Brien et al. Braz J Phys Ther. 2016;20(5):477-489.
Background: These trials are the first randomised controlled trials of telephone-based weight management and healthy lifestyle interventions for low back pain and knee osteoarthritis. This article describes the protocol and statistical analysis plan.
Methods: These trials are parallel randomised controlled trials that investigate and compare the effect of a telephone-based weight management and healthy lifestyle intervention for improving pain intensity in overweight or obese patients with low back pain or knee osteoarthritis. The analysis plan was finalised prior to initiation of analyses. All data collected as part of the trial were reviewed, without stratification by group, and classified by baseline characteristics, process of care and trial outcomes. Trial outcomes were classified as primary and secondary outcomes. Appropriate descriptive statistics and statistical testing of between-group differences, where relevant, have been planned and described.
Conclusions: A protocol for standard analyses was developed for the results of two randomised controlled trials. This protocol describes the data, and the pre-determined statistical tests of relevant outcome measures. The plan demonstrates transparent and verifiable use of the data collected. This a priori protocol will be followed to ensure rigorous standards of data analysis are strictly adhered to.
Development and validation of a screening tool to predict the risk of chronic low back pain in patients presenting with acute low back pain: a study protocol.
Traeger et al. BMJ Open. 2015 Jul 15;5(7):e007916.
Introduction: Around 40% of people presenting to primary care with an episode of acute low back pain develop chronic low back pain. In order to reduce the risk of developing chronic low back pain, effective secondary prevention strategies are needed. Early identification of at-risk patients allows clinicians to make informed decisions based on prognostic profile, and researchers to select appropriate participants for secondary prevention trials. The aim of this study is to develop and validate a prognostic screening tool that identifies patients with acute low back pain in primary care who are at risk of developing chronic low back pain. This paper describes the methods and analysis plan for the development and validation of the tool.
Methods/analysis: The prognostic screening tool will be developed using methods recommended by the prognosis research strategy (progress) group and reported using the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (tripod) statement. In the development stage, we will use data from 1248 patients recruited for a prospective cohort study of acute low back pain in primary care. We will construct 3 logistic regression models to predict chronic low back pain according to 3 definitions: any pain, high pain and disability at 3 months. In the validation stage, we will use data from a separate sample of 1643 patients with acute low back pain to assess the performance of each prognostic model. We will produce validation plots showing nagelkerke r(2) and brier score (overall performance), area under the curve statistic (discrimination) and the calibration slope and intercept (calibration).
Ethics and dissemination: Ethical approval from the university of sydney ethics committee was obtained for both of the original studies that we plan to analyse using the methods outlined in this protocol (henschke et al, ref 11-2002/3/3144; williams et al, ref 11638).
Pain and Moderate to Vigorous Physical Activity in Adolescence: An International Population-Based Survey.
Swain et al. Pain Med. 2015 [Epub ahead of print].
Objective: To evaluate whether individual types of pain (headache, stomach-ache, and backache) or multiple pains affect the odds of young people achieving the recommended 60 minutes of moderate to vigorous physical activity (mvpa) per day in a large representative sample.
Design: Multicenter cross-sectional survey.
Setting: Twenty-eight countries across europe and north america.
Subjects: Adolescents (n = 242,103).
Methods: An analysis of data collected in two waves (2001/02 and 2005/06) of the health behavior in school-aged children (hbsc) study was performed. Survey questions included the hbsc symptoms checklist and the amount of regular physical activity. Multilevel logistic regression was used to account for clustering effect of mvpa within countries. Models investigated the relationship between pain and physical activity, adjusted for the hbsc study year. Six models were conducted separately for gender and age-group (11, 13, and 15 years) strata.
Results: In general, the presence of pain was associated with reduced physical activity. Headache alone was associated with reduced physical activity in all six strata (odd ratios 0.77-0.84), stomach-ache alone in five strata (0.77-0.92), and backache alone in four strata (0.86-0.96). In 11- and 13-year-old girls, headache, stomach-ache, and backache, individually and in combination, were associated with decreased odds of being physically active (odds ratios ranging from 0.73 to 0.91). Within the other four age and gender strata, the relationship was less consistent.
Conclusion: Pain is associated with reduced physical activity in adolescents but this association varies according to gender, age, and the type of pain experienced.
The association between symptom severity and physical activity participation in people seeking care for acute low back pain.
Gomes et al. Eur Spine J. 2015 Mar;24(3):452-7.
Purpose: To investigate the association between symptom severity and physical activity participation in people with acute non-specific low back pain (LBP).
Methods: The sample included a total of 999 patients who presented to primary care with an acute episode of low back pain. Symptom severity, in terms of activity limitation and severity of pain; and physical activity participation before (habitual) and after pain onset were assessed using self-report questionnaires. All participants were interviewed within 14 days of pain onset.
Results: At interview most of the participants (87.5 %) reported having moderate to extreme activity limitation due to back pain. There was a significant decrease in physical activity participation after pain onset (mean difference: -176 min, 95 % CI 327-400; p < 0.0001) but no association between habitual or change in physical activity participation and symptom severity was observed (p > 0.21).
Conclusion: Pain onset causes a significant and immediate decrease in physical activity participation, but this change does not seem to be associated with symptom severity.
Why and how back pain interventions work: What can we do to find out?
Mansell et al. Best Prac Res Clin Rheumatol. 2013;27(5):685-97
Mediation analysis is a useful research method that potentially allows identification of the mechanisms through which treatments affect patient outcomes. This chapter reviews the theoretical framework, research designs and statistical approaches used in mediation analysis. It describes what can be learnt from previous mediation research, much of which has investigated mediating factors of psychosocial interventions in other health conditions. It also summarises the few treatment-mediation studies of psychosocial interventions conducted in back pain. This chapter shows that there is emerging evidence about the role of some psychological factors as potential treatment mediators, such as self-efficacy and catastrophising. Mediation analysis can equally be applied to non-psychological factors. Pre-planned and appropriately conducted mediation analysis in adequately powered clinical trials would be a step forward in understanding treatment effects in back pain and improving patient management.
Age does not modify effects of treatment on pain in patients with low back pain – secondary analyses of randomised clinical trials
Ferreira et al. Eur J Pain 2014;15(7): 932-38
Background
While many treatment options have been advocated to speed recovery in adults with back pain, it is still unclear whether older patients with back pain respond differently to treatment when compared to younger patients.
Aims
This study aims to evaluate if age modifies response to treatment in patients with back pain, by conducting secondary analyses of seven randomized clinical trials of common interventions for back pain.
Methods
Data from 1233 participants were sourced from two randomized clinical trials on patients with acute back pain and five on patients with persistent back pain. Trials were conducted between 2001 and 2010 and assessed conservative treatments for back pain, including exercise, spinal manipulative therapy and anti-inflammatory drugs. Individual participant data analyses were performed using a ‘one-stage’ approach including all available data in a single two-level model, with participants being one level and trials being the second level. Only pain outcomes assessed immediately after treatment were included in the analyses.
Results
Mean combined age of included participants was 49 years (SD: 15.4). Multivariate fractional polynomial analyses revealed no significant interaction (p > 0.05) between age and treatment effect sizes in patients with low back pain for any of the treatment comparisons.
Conclusion
These results offer preliminary evidence suggesting that the generally small effects of conservative treatments for low back pain are in fact observed across all age groups.
An international survey of pain in adolescents.
Swain et al. BMC Public Health 2014;14:447
Background
A common belief is that pain is uncommon and short lived in adolescents. However, the burden of pain in adolescents is unclear because of limitations in previous research. The aim of this study is to estimate the prevalence of headache, stomach-ache and backache in adolescents and to explore the extent to which these three forms of pain coexist based upon a representative sample of adolescents from 28 countries.
Methods
Data were analysed from three consecutive waves (1997/98, 2001/02 and 2005/06) of the health behavior in school-aged children: who collaborative cross-national survey (hbsc). Prevalence estimates are based upon adolescents who reported experiencing headache, stomach-ache or backache at least monthly for the last 6 months.
Results
There were a total of 404,206 participants with a mean (±sd) age of 13.6 (±1.7) years (range 9.8 to 17.3 years). The prevalence of headache was 54.1%, stomach-ache 49.8%, backache 37%, and at least one of the three pains 74.4%. Girls had a higher prevalence of the three pains than boys and the prevalence of pain increased with age. Headache, stomach-ache and backache frequently coexist, for example, of those with headache: 21.2% had headache alone, 31% suffered from both headache and stomach-ache, 12.1% suffered from backache and headache, and 35.7% had all three pains.
Conclusions
Somatic pain is very common in adolescents, more often coexisting than occurring in isolation. Our data supports the need for further research to improve the understanding of these pains in adolescents.
Low-back pain in children and adolescents: a systematic review and meta-analysis evaluating the effectiveness of conservative interventions.
Michaleff et al. Eur Spine J. 2014;23(10):2046-58
Purpose
To identify and evaluate the effectiveness of conservative treatment approaches used in children and adolescents to manage and prevent low back pain (LBP).
Methods
Five electronic databases and the reference lists of systematic reviews were searched for relevant studies. Randomised controlled trials (RCTs) were considered eligible for inclusion if they enrolled a sample of children or adolescents (<18 years old) and evaluated the effectiveness of any conservative intervention to treat or prevent LBP. Two authors independently screened search results, extracted data, assessed risk of bias using the PEDro scale, and rated the quality of evidence using the GRADE criteria.
Results
Four RCTs on intervention and eleven RCTs on prevention of LBP were included. All included studies had a high risk of bias scoring ≤7 on the PEDro scale. For the treatment of LBP, a supervised exercise program compared to no treatment improved the average pain intensity over the past month by 2.9 points (95 % CI 1.6-4.1) measured by a 0-10 scale (2 studies; n = 125). For the prevention of LBP, there was moderate quality evidence to suggest back education and promotion programs are not effective in reducing LBP prevalence in children and adolescents.
Conclusions
While exercise interventions appear to be promising to treat LBP in children and adolescents, there is a dearth of research data relevant to paediatric populations. Future studies conducted in children and adolescents with LBP should incorporate what has been learnt from adult LBP research and be of rigorous methodological quality.
Measurement tools for adherence to non-pharmacological self-management treatment for chronic musculoskeletal conditions: a systematic review.
Hall et al. Arch Phys Med Rehabil. 2015;96(3):552-62
Objectives
To identify measures of adherence to nonpharmacologic self-management treatments for chronic musculoskeletal (MSK) populations; and to report on the measurement properties of identified measures.
Data Sources
Five databases were searched for all study types that included a chronic MSK population, unsupervised intervention, and measure of adherence.
Study Selection
Two independent researchers reviewed all titles for inclusion using the following criteria: adult (>18y) participants with a chronic MSK condition; intervention, including an unsupervised self-management component; and measure of adherence to the unsupervised self-management component.
Data Extraction
Descriptive data regarding populations, unsupervised components, and measures of unsupervised adherence (items, response options) were collected from each study by 1 researcher and checked by a second for accuracy.
Data Synthesis
No named or referenced adherence measurement tools were found, but a total of 47 self-invented measures were identified. No measure was used in more than a single study. Methods could be grouped into the following: home diaries (n=31), multi-item questionnaires (n=11), and single-item questionnaires (n=7). All measures varied in type of information requested and scoring method. The lack of established tools precluded quality assessment of the measurement properties using COnsensus-based Standards for the selection of health Measurement INstruments methodology.
Conclusions
Despite the importance of adherence to self-management interventions, measurement appears to be conducted on an ad hoc basis. It is clear that there is no consistency among adherence measurement tools and that the construct is ill-defined. This study alerts the research community to the gap in measuring adherence to self-care in a rigorous and reproducible manner. Therefore, we need to address this gap by using credible methods (eg, COnsensus-based Standards for the selection of health Measurement INstruments guidelines) to develop and evaluate an appropriate measure of adherence for self-management.
Multidisciplinary biopsychosocial rehabilitation for chronic low back pain. A Cochrane systematic review and meta-analysis.
Kamper et al. BMJ. 2015;350:h444.
Objective
To assess the long term effects of multidisciplinary biopsychosocial rehabilitation for patients with chronic low back pain.
Design
Systematic review and random effects meta-analysis of randomised controlled trials.
Data Sources
Electronic searches of Cochrane Back Review Group Trials Register, CENTRAL, Medline, Embase, PsycINFO, and CINAHL databases up to February 2014, supplemented by hand searching of reference lists and forward citation tracking of included trials.
Study Selection Criteria
Trials published in full; participants with low back pain for more than three months; multidisciplinary rehabilitation involved a physical component and one or both of a psychological component or a social or work targeted component; multidisciplinary rehabilitation was delivered by healthcare professionals from at least two different professional backgrounds; multidisciplinary rehabilitation was compared with a non- multidisciplinary intervention.
Results
Forty one trials included a total of 6858 participants with a mean duration of pain of more than one year who often had failed previous treatment. Sixteen trials provided moderate quality evidence that multidisciplinary rehabilitation decreased pain (standardised mean difference 0.21, 95% confidence interval 0.04 to 0.37; equivalent to 0.5 points in a 10 point pain scale) and disability (0.23, 0.06 to 0.40; equivalent to 1.5 points in a 24 point Roland-Morris index) compared with usual care. Nineteen trials provided low quality evidence that multidisciplinary rehabilitation decreased pain (standardised mean difference 0.51, -0.01 to 1.04) and disability (0.68, 0.16 to 1.19) compared with physical treatments, but significant statistical heterogeneity across trials was present. Eight trials provided moderate quality evidence that multidisciplinary rehabilitation improves the odds of being at work one year after intervention (odds ratio 1.87, 95% confidence interval 1.39 to 2.53) compared with physical treatments. Seven trials provided moderate quality evidence that multidisciplinary rehabilitation does not improve the odds of being at work (odds ratio 1.04, 0.73 to 1.47) compared with usual care. Two trials that compared multidisciplinary rehabilitation with surgery found little difference in outcomes and an increased risk of adverse events with surgery.
Conclusions
Multidisciplinary biopsychosocial rehabilitation interventions were more effective than usual care (moderate quality evidence) and physical treatments (low quality evidence) in decreasing pain and disability in people with chronic low back pain. For work outcomes, multidisciplinary rehabilitation seems to be more effective than physical treatment but not more effective than usual care.
How does pain lead to disability? A systematic review and meta-analysis of mediation studies in people with back and neck pain.
Lee et al. Pain. 2015: 156;988-97.
Disability is an important outcome from a clinical and public health perspective. However, it is unclear how disability develops in people with low back pain or neck pain. More specifically, the mechanisms by which pain leads to disability are not well understood. Mediation analysis is a way of investigating these mechanisms by examining the extent to which an intermediate variable explains the effect of an exposure on an outcome. This systematic review and meta-analysis aimed to identify and examine the extent to which putative mediators explain the effect of pain on disability in people with low back pain or neck pain. Five electronic databases were searched. We found 12 studies (N = 2961) that examined how pain leads to disability with mediation analysis. Standardized regression coefficients (β) of the indirect and total paths were pooled. We found evidence to show that self-efficacy (β = 0.23, 95% confidence interval [CI] = 0.10 to 0.34), psychological distress (β = 0.10, 95% CI = 0.01 to 0.18), and fear (β = 0.08, 95% CI = 0.01 to 0.14) mediated the relationship between pain and disability, but catastrophizing did not (β = 0.07, 95% CI = -0.06 to 0.19). The methodological quality of these studies was low, and we highlight potential areas for development. Nonetheless, the results suggest that there are significant mediating effects of self-efficacy, psychological distress, and fear, which underpins the direct targeting of these constructs in treatment.
Does adherence to treatment mediate the relationship between patients’ treatment outcome expectancies and recovery from acute low back pain?
Haanstra et al. Pain. 2015: 156;1530-36.
It is believed that patients’ expectancies about the effectiveness of treatment influence their treatment outcomes, but the working mechanism is rarely studied in patients with low back pain. Theoretical models suggest that adherence to treatment may be an important pathway. The aim of this study was to assess the mediating role of adherence to treatment in the relationship between expectancies and the outcomes of recovery and pain intensity in patients with acute low back pain. This study used data from a randomized placebo-controlled trial of paracetamol for acute low back pain. Expectancies were measured with the Credibility Expectancy Questionnaire. Adherence was measured with a medication diary. Pain intensity was recorded daily in a diary on a 0 to 10 pain scale, and recovery was defined as the first of 7 consecutive days scoring 0 or 1 on a 6-point pain scale. Cox regression (dependent variable: recovery) and linear mixed-model analyses (dependent variable: daily pain intensity scores) were performed. The “difference in coefficients” approach was used to establish mediation. A total of 1573 participants were included in current analyses. There was a small but highly significant relationship between expectancies and outcomes; 3.3% of the relationship between expectancies and recovery and 14.2% of the relationship between expectancies and pain intensity were mediated by adherence to treatment. This study does not convincingly support the theory that adherence is a key pathway in the relationship between treatment outcome expectancies and recovery and pain intensity in this acute low back pain population.
Tweeting back: predicting new cases of back pain with mass social media data.
Lee et al. J Am Med Informatics Assoc. 2015:23(3);644-48
Background
Back pain is a global health problem. Recent research has shown that risk factors that are proximal to the onset of back pain might be important targets for preventive interventions. Rapid communication through social media might be useful for delivering timely interventions that target proximal risk factors. Identifying individuals who are likely to discuss back pain on Twitter could provide useful information to guide online interventions.
Methods
We used a case-crossover study design for a sample of 742 028 tweets about back pain to quantify the risks associated with a new tweet about back pain.
Results
The odds of tweeting about back pain just after tweeting about selected physical, psychological, and general health factors were 1.83 (95% confidence interval [CI], 1.80-1.85), 1.85 (95% CI: 1.83-1.88), and 1.29 (95% CI, 1.27-1.30), respectively.
Conclusion
These findings give directions for future research that could use social media for innovative public health interventions.
Does changing pain-related knowledge reduce pain and improve function through changes in catastrophizing?
Lee et al. Pain 2016:157(4);922-30
Evidence from randomized controlled studies shows that reconceptualizing pain improves patients’ knowledge of pain biology, reduces catastrophizing thoughts, and improves pain and function. However, causal relationships between these variables remain untested. It is hypothesized that reductions in catastrophizing could mediate the relationship between improvements in pain knowledge and improvements in pain and function. To test this causal mechanism, we conducted longitudinal mediation analyses on a cohort of 799 patients who were exposed to a pain education intervention. Patients provided responses to the neurophysiology of pain questionnaire, catastrophic thoughts about pain scale, visual analogue pain scale, and the patient specific functional scale, at baseline, 1-month, 6-month, and 12-month follow-up. With adjustment for potential confounding variables, an improvement in pain biology knowledge was significantly associated with a reduction in pain intensity (total effect = -2.20, 95% confidence interval [CI] = -2.96 to -1.44). However, this effect was not mediated by a reduction in catastrophizing (indirect effect = -0.16, 95% CI = -0.36 to 0.02). This might be due to a weak, nonsignificant relationship between changes in catastrophizing and pain intensity (path b = 0.19, 95% CI = -0.03 to 0.41). Similar trends were found in models with function as the outcome. Our findings indicate that change in catastrophizing did not mediate the effect of pain knowledge acquisition on change in pain or function. The strength of this conclusion is moderated, however, if patient-clinician relational factors are conceptualized as a consequence of catastrophizing, rather than a cause.
Overview of musculoskeletal pain in children and adolescents.
Kamper et al. Braz J Phys Ther 2016:20(3);275-84
Introduction: Musculoskeletal (MSK) pain in children and adolescents is responsible for substantial personal impacts and societal costs, but it has not been intensively or systematically researched. This means our understanding of these conditions is limited, and healthcare professionals have little empirical evidence to underpin their clinical practice. In this article we summarise the state of the evidence concerning MSK pain in children and adolescents, and offer suggestions for future research.
Results: Rates of self-reported MSK pain in adolescents are similar to those in adult populations and they are typically higher in teenage girls than boys. Epidemiological research has identified conditions such as back and neck pain as major causes of disability in adolescents, and in up to a quarter of cases there are impacts on school or physical activities. A range of physical, psychological and social factors have been shown to be associated with MSK pain report, but the strength and direction of these relationships are unclear. There are few validated instruments available to quantify the nature and severity of MSK pain in children, but some show promise. Several national surveys have shown that adolescents with MSK pain commonly seek care and use medications for their condition. Some studies have revealed a link between MSK pain in adolescents and chronic pain in adults.
Conclusion: Musculoskeletal pain conditions are often recurrent in nature, occurring throughout the life-course. Attempts to understand these conditions at a time close to their initial onset may offer a better chance of developing effective prevention and treatment strategies.
Estimating the risk of chronic pain: development and validation of a prognostic model (PiCkuP) for patients with acute low back pain.
Traeger et al. PLoS Medicine 2016:13(5);e1002019
Background
Low back pain (LBP) is a major health problem. Globally it is responsible for the most years lived with disability. The most problematic type of LBP is chronic LBP (pain lasting longer than 3 mo); it has a poor prognosis and is costly, and interventions are only moderately effective. Targeting interventions according to risk profile is a promising approach to prevent the onset of chronic LBP. Developing accurate prognostic models is the first step. No validated prognostic models are available to accurately predict the onset of chronic LBP. The primary aim of this study was to develop and validate a prognostic model to estimate the risk of chronic LBP.
Methods and Findings
We used the PROGRESS framework to specify a priori methods, which we published in a study protocol. Data from 2,758 patients with acute LBP attending primary care in Australia between 5 November 2003 and 15 July 2005 (development sample, n = 1,230) and between 10 November 2009 and 5 February 2013 (external validation sample, n = 1,528) were used to develop and externally validate the model. The primary outcome was chronic LBP (ongoing pain at 3 mo). In all, 30% of the development sample and 19% of the external validation sample developed chronic LBP. In the external validation sample, the primary model (PICKUP) discriminated between those who did and did not develop chronic LBP with acceptable performance (area under the receiver operating characteristic curve 0.66 [95% CI 0.63 to 0.69]). Although model calibration was also acceptable in the external validation sample (intercept = -0.55, slope = 0.89), some miscalibration was observed for high-risk groups. The decision curve analysis estimated that, if decisions to recommend further intervention were based on risk scores, screening could lead to a net reduction of 40 unnecessary interventions for every 100 patients presenting to primary care compared to a “treat all” approach. Limitations of the method include the model being restricted to using prognostic factors measured in existing studies and using stepwise methods to specify the model. Limitations of the model include modest discrimination performance. The model also requires recalibration for local settings.
Conclusions
Based on its performance in these cohorts, this five-item prognostic model for patients with acute LBP may be a useful tool for estimating risk of chronic LBP. Further validation is required to determine whether screening with this model leads to a net reduction in unnecessary interventions provided to low-risk patients.
Short-term clinical course of knee pain in children and adolescents: A feasibility study using electronic methods of data collection.
Swain et al 2016 Physiother Res Int (online)
Background and Purpose
Musculoskeletal disorders, such as knee pain, are common in children and adolescents, but there is a lack of high quality research that evaluates the clinical course of these conditions. The objective of this study was to evaluate the feasibility of conducting a prospective study of children and adolescents with knee pain using electronic methods of data collection.
Methods
Children and adolescents with knee pain that presented to primary care physiotherapy clinics were enrolled and followed-up on a weekly basis via short messaging service (SMS) until their knee pain had recovered (i.e. two consecutive weeks of no pain). Feasibility was assessed in terms of recruitment, retention and response rates to SMS and an online questionnaire. Baseline and 6-month follow-up measures included pain, disability, physical function, physical activity and health related quality of life. Kaplan-Meier survival analysis was used to estimate the median time to knee pain recovery.
Results
Thirty participants (mean age 13.0 ± 2.2 years, 53% boys) were recruited over 26 months. The overall response rate to weekly SMS follow-up was 71.3% (809 received/1135 sent). One third of participants stopped responding to SMS prior to recovery, and these participants typically had a much lower response rate during the time they remained in the study. At 6-month follow-up, 80% of the cohort completed the final online questionnaire, and 29% of participants still reported current knee pain (≥1/10 VAS). The median time for knee pain recovery was 8 weeks (95%CI: 5, 10).
Conclusion
Electronic data collection alone seems insufficient to track pain recovery in young people and may need to be supplemented with more traditional data collection methods. Researchers should consider further measures to address slow recruitment rates and high attrition when designing large prospective studies of children and adolescents in the future
Whose pain is it anyway? Comparability of pain report from children and their parents.
Kamper et al Chiro Man Ther 2016: 24:24
Background
There is a high demand for robust research into understanding the scope and consequences of musculoskeletal pain in children. An important part of this involves clarifying issues surrounding its measurement, not least differences in reporting from the children themselves and their parents. Therefore this study will assess the degree of agreement between parents’ report of their child’s pain and the child’s own assessment.
Methods
Data were collected in 2013 and 2014 as part of a larger cohort study investigating the health of Danish school children. Two study samples included 354 and 334 child-parent pairs who were independently asked whether the child had experienced musculoskeletal pain in the previous week. Children were between the ages of 10 and 14 years old. Parents provided answers via text message and children were questioned in person or via questionnaire at their school.
Results
Percentage agreement between parent and child assessment was around 50 % in Sample 1 and 68 % in Sample 2. The poor agreement was due to children reporting pain when their parent did not, the reverse very rarely occurred. Pain of greater intensity or longer duration resulted in better agreement between the child and parent. Child age and gender did not influence the likelihood of agreement.
Conclusion
Children often experience pain that is not reported by their parents resulting in poor concordance between pain reports from the two sources. While it is not possible to say which is more valid we can conclude they are not interchangeable.
Models of Care for addressing chronic musculoskeletal pain and health in children and adolescents.
Stinson et al. Best Prac Res Clin Rheumatol. 2016:30(3);468-82
Chronic musculoskeletal pain among children and adolescents is common and can negatively affect quality of life. It also represents a high burden on the health system. Effective models of care for addressing the prevention and management of pediatric musculoskeletal pain are imperative. This chapter will address the following key questions: (1) Why are pediatric-specific models of pain care needed? (2) What is the burden of chronic musculoskeletal pain among children and adolescents? (3) What are the best practice approaches for early identification and prevention of chronic musculoskeletal pain in children and adolescents? (4) What are the recommended strategies for clinical management of chronic pain, including pharmacological, physical, psychological and complementary, and alternative approaches? (5) What are the most effective strategies for implementing models of pain care across different care settings? (6) What are the research priorities to improve models of care for children and adolescents with chronic musculoskeletal pain?
Spinal pain in Danish school children – how often and how long? The CHAMPS Study-DK.
Dissing et al. BMC Musculoskelet Disord. 2017;18(1):67.
Background
Spinal pain in children and adolescents is a common condition, usually transitory, but the picture of spinal pain still needs elucidation, mainly due to variation in measurement methods. The aim of this study was to describe the occurrence of spinal pain in 8–15 year-old Danish school children, over a 3-year period. Specifically determining the characteristics of spinal pain in terms of frequency and duration.
Methods
The study was a 3-year prospective longitudinal cohort study including 1400 school children. The outcomes were based on weekly text messages (SMS) to the parents inquiring about the child’s musculoskeletal pain, and on clinical data from examinations of the children.
Results
The 3-year prevalence was 55%. The prevalence was 29%, 33% and 31% for each of the three study years respectively, and increased statistically significantly with age, especially for lumbopelvic pain. Most children had few and short-lasting episodes with spinal pain, but more than one out of five children had three or more episodes during a study year and 17% of all episodes lasted for more than 4 weeks.
Conclusion
This study demonstrates that spinal pain is a substantial problem. Most episodes are brief, but there are a vast number of children with frequent and long-lasting episodes of spinal pain indicating a need for action regarding evidence-based prevention and management.