Measurement Error, Minimal Detectable Change, and Minimal Clinically Important Difference of the Short Form-36 Health Survey, Hospital Anxiety and Depression Scale, and Pain Numeric Rating Scale in Patients With Chronic Pain.

In both pain research and clinical practice, patient-reported outcome measures are used to assess dimensions of health. Interpreting these instruments requires understanding their measurement error and what magnitude of change has subjective importance for patients. This study estimated the standard error of measurement, 1-year minimal detectable change, and 1-year minimal clinically important difference (MCID) for the Short Form-36 Health Survey physical component summary and mental component summary, the Hospital Anxiety and Depression Scale subscales for anxiety symptoms and depression symptoms, and the numeric rating scale for past-week average pain intensity. MCIDs for these instruments have not previously been estimated in a large sample of chronic pain patients participating in interdisciplinary pain rehabilitation. Data were drawn from the Swedish Quality Registry for Pain Rehabilitation (n = 8,854 patients). MCID was estimated as average change and change difference based on 3 different anchors. MCID estimates were 2.62 to 4.69 for Short Form-36 Health Survey physical component summary, 4.46 to 6.79 for Short Form-36 Health Survey mental component summary, .895 to 1.48 for numeric rating scale, 1.17 to 2.13 for anxiety symptoms in the Hospital Anxiety and Depression Scale, and 1.48 to 2.54 for depression symptoms in the Hospital Anxiety and Depression Scale. The common assumption of an identical standard error of measurement for pre- and post-treatment measurements was not always applicable. When estimating MCID, researchers should select an estimation method and anchor aligned with the study's context and objectives. PERSPECTIVE: This article presents estimates of MCID and minimal detectable change for several commonly used patient-reported outcome measures among patients with chronic pain. These estimates can help clinicians and researchers to determine when a measured health improvement is subjectively important to the patient and greater than measurement error.

Protocol for identifying and characterising critical physical tasks in the military: Development and validation.

BACKGROUND: When establishing Physical Employment Standards, validity is dependent on the correct identification and characterisation of critical job tasks. OBJECTIVE: To develop and validate a standardised protocol for the identification, characterisation, and documentation of critical physical job tasks in military occupational specialities in the Swedish Armed Forces (SwAF), and propose a definition of critical physical job tasks for use in the SwAF. METHODS: A protocol was drafted with three content domains, including a preliminary definition. Protocol content validity was iteratively assessed in two consecutive stages where ten subject experts rated relevance and simplicity. A consensus panel revised the protocol after each stage. Content validity index (CVI) was calculated as item-CVI (I-CVI) per each feature and as scale average (S-CVI/Ave) per content domain. Acceptable content validity thresholds were 0.78 and 0.90, respectively. RESULTS: The validated protocol consisted of 35 items with an I-CVI≥0.90 and≥0.80 for relevance and simplicity, respectively. The S-CVI/Ave was 0.97 for relevance and 0.98 for simplicity. The protocol was language reviewed, reorganised for easy use, and approved by the consensus panel. The final protocol includes: background and aim of the protocol, the accepted generic and critical physical job task definitions, protocol instructions, subject expert-qualifications, job task source and characteristics. CONCLUSION: A standardised protocol for identification and characterisation of critical job tasks in SwAF military occupational specialties was developed. The protocol content was rated relevant and simple by experts and will be of importance in future work establishing physical requirements in the SwAF.

High Self-Reported Levels of Pain 1 Year After a Myocardial Infarction Are Related to Long-Term All-Cause Mortality: A SWEDEHEART Study Including 18 376 Patients.

Background Pain increases the risk for cardiovascular diseases, including myocardial infarction (MI). However, the impact of pain on mortality after MI has not yet been investigated in large studies with long-term follow-up periods. Thus, we aimed to examine various levels of pain severity 1 year after an MI as a potential risk for all-cause mortality. Methods and Results We collected data from 18 376 patients, aged <75 years, who had a registered MI event during the period from 2004 to 2013 and with measurements of potential cardiovascular risk indicators at hospital discharge from the Swedish quality register SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies). Self-reported levels of experienced pain according to EuroQol-5 dimension instrument were recorded in secondary prevention clinics 1 year after hospital discharge. We collected all-cause mortality data up to 8.5 years (median, 3.4 years) after the 1-year visit. The Cox proportional hazard regression was used to estimate hazard ratio (HR) and 95% CI. Moderate pain and extreme pain were reported by 38.2% and 4.5%, respectively, of included patients. There were 1067 deaths. Adjusted HR was 1.35 (95% CI, 1.18-1.55) and 2.06 (95% CI, 1.63-2.60) for moderate and extreme pain, respectively. Pain was a stronger mortality predictor than smoking. Conclusions Pain 1 year after MI is highly prevalent, and its effect on mortality 1 year after MI was found to be more pronounced than smoking. Clinicians managing patients after MI should recognize the need to consider experienced pain when making prognosis or treatment decisions.

Acute exercise as active inference in chronic musculoskeletal pain, effects on gait kinematics and muscular activity in patients and healthy participants: a study protocol for a randomised controlled laboratory trial.

INTRODUCTION: Chronic musculoskeletal pain is a highly prevalent, complex and distressing condition that may negatively affect all domains of life. In view of an active inference framework, and resting on the concept of allostasis, human movement per se becomes a prerequisite for health and well-being while chronic pain becomes a sign of a system unable to attenuate an allostatic load. Previous studies on different subgroups of chronic pain conditions have demonstrated alterations in gait kinematics and muscle activity, indicating shared disturbances in the motor system from long-term allostatic load. We hypothesise that such alterations exist in heterogenous populations with chronic musculoskeletal pain, and that exposure to acute and controlled exercise may attenuate these alterations. Therefore, the main aim of this study is to investigate the acute effects of exercise on gait kinematics and activity of the back and neck muscles during diverse walking conditions in patients with chronic musculoskeletal pain compared with a reference sample consisting of healthy participants. METHODS AND ANALYSIS: This two-sample two-armed parallel randomised controlled laboratory trial will include 40 participants with chronic musculoskeletal pain (>3 months) and 40 healthy participants. Participants will be randomly allocated to either 30 min of aerobic exercise or rest. Primary outcomes are gait kinematics (walking speed, step frequency, stride length, lumbar rotation, gait stability) and muscular activity (spatial and temporal) of the back and neck during diverse walking conditions. Secondary outcomes are variability of gait kinematics and muscle activity and subjective pain ratings assessed regularly during the trial. ETHICS AND DISSEMINATION: The study has been approved by the Regional Ethics Review Board in Uppsala, Sweden (#2018/307). Findings will be disseminated via conference presentations, publications in peer-reviewed journals and engagement with patient support groups and clinicians. TRIAL REGISTRATION NUMBER: NCT03882333.

Healthcare Professionals' Perceptions of and Attitudes towards a Standardized Content Description of Interdisciplinary Rehabilitation Programs for Patients with Chronic Pain-A Qualitative Study.

Interdisciplinary pain rehabilitation (IPR) is a recommended treatment for people with chronic pain. An inadequate description of the content of IPR programs makes it difficult to draw conclusions regarding their effects. The purpose of this study was to describe the perceptions and attitudes of healthcare professionals toward a content description of IPR programs for patients with chronic pain. Individual interviews with healthcare professionals (n = 11) working in IPR teams in Sweden were conducted between February and May 2019. Analysis of the interviews resulted in a theme: interdisciplinary pain rehabilitation is a complex intervention, with three categories: limitations in the description of IPR programs; lack of knowledge about IPR and chronic pain; and facilitating and hindering factors for using the content description of IPR programs. Conclusion: Healthcare professionals perceived that IPR programs could be described through a general content description. A general content description could enhance the quality of IPR programs through a better understanding of their content and a comparison of different IPR programs. Healthcare professionals also expressed the importance of a content description being a guide rather than a steering document.

Evaluation of content validity and feasibility of the eVISualisation of physical activity and pain (eVIS) intervention for patients with chronic pain participating in interdisciplinary pain rehabilitation programs.

BACKGROUND: Chronic pain negatively influences most aspects of life, including aerobic capacity and physical function. The "eVISualisation of physical activity and pain" (eVIS) intervention was developed to facilitate individualized physical activity for treatment in interdisciplinary pain rehabilitation programs (IPRPs). The objective of this study was to evaluate the content validity and feasibility of the eVIS intervention prior to an effectiveness trial. METHODS: In order to determine pre-clinical content validity, experts (n = 10) (patients, caregivers, researchers) participated in three assessment rounds using a Likert-scale survey where relevance, simplicity, and safety were rated, whereafter the intervention was revised. Item-content validity index (I-CVI), average, and overall CVI were used to quantify ratings. To determine content validity and feasibility in the clinical context, experts (n = 8) (patients and physiotherapists) assessed eVIS after a 2-3-week test trial, with the feasibility aspects acceptability, demand, implementation, limited efficacy-testing, and practicality in focus. Additional expert interviews (with physiotherapists, physicians) were conducted on two incomplete areas. RESULTS: The intervention was iteratively revised and refined throughout the study. After three assessment and revision rounds, the I-CVI ratings for relevance, simplicity, and safety ranged between 0.88 and 1.00 (≥0.78) in most items, giving eVIS "excellent" content validity. In the IPRP context, the intervention emerged as valid and feasible. Additional interviews further contributed to its content validity and clinical feasibility. CONCLUSIONS: The proposed domains and features of the eVIS intervention are deemed valid in its content and feasible in the IPRP context. The consecutive step-by-step evaluation process enabled careful intervention development with revisions to be made in close collaboration with stakeholders. Findings implicate a robust base ahead of the forthcoming effectiveness trial.

Evidence-based digital support during 1 year after an Interdisciplinary Pain Rehabilitation Programme for persons with chronic musculoskeletal pain to facilitate a sustainable return to work: a study protocol for a registry-based multicentre randomised controlled trial.

INTRODUCTION: Chronic musculoskeletal pain (CMSP) severely affects the individual's quality of life, functioning and ability to work, and comes with significant societal costs for sick leave and productivity loss. After rehabilitation, patients with CMSP often experience lack of support when responsibility for the return-to-work process is taken over by the employer. Therefore, we aim to evaluate the effectiveness of a digital support (Sustainable WorkEr digital support for Persons with chronic Pain and their Employers (SWEPPE)) for promoting a sustainable return-to-work for persons with CMSP and to facilitate the employers' supportive role and responsibilities in the process. METHODS AND ANALYSIS: In this registry-based multicentre randomised controlled trial, 360 patients with CMSP will be randomised to either receive the smartphone application SWEPPE (n=180) or to a control group (n=180). The intervention group will use SWEPPE for 1 year and the control group will not receive any intervention for return to work (RTW). Participants will be recruited from approximately 10 specialist and primary care level units connected to the Swedish National Quality Registry for Pain Rehabilitation providing Interdisciplinary Pain Rehabilitation Programmes (IPRP) for CMSP. Eligibility criteria are age 18-65 years and a need for support in RTW or continued support at work for creating a sustainable work situation. Baseline data will be collected when the participants have completed the IPRP. Final assessment will be performed after 12 months. The primary outcome will be a number of days with sickness cash benefit. Secondary outcomes and explanatory variables including important domains affected by CMSP such as health-related quality of life, functioning and work ability will be collected. ETHICS AND DISSEMINATION: The Swedish Ethics Review Board approved the study (Dnr 2020-01593, Dnr 2021-01854). The study findings will be disseminated through publication, national and international conferences, and meetings to be available for patients, healthcare providers or stakeholders. TRIAL REGISTRATION NUMBER: NCT05058547.

Effectiveness of the eVISualisation of physical activity and pain intervention (eVIS) in Swedish Interdisciplinary Pain Rehabilitation Programmes: study protocol for a registry-based randomised controlled clinical trial.

INTRODUCTION: Living with chronic pain often involves negative consequences. Interdisciplinary Pain Rehabilitation Programmes (IPRP) is considered superior to single-treatment measures in patients with chronic pain. Despite this, effects emerge suboptimal and more than 20% of patients deteriorate in patient-reported physical health outcomes after IPRP. A novel e-Health intervention, eVISualisation (eVIS) of physical activity and pain, was systematically developed to facilitate individualisation of physical activity levels. By adding elements of data collection, visualisation and communication of objectively measured physical activity and patient-reported outcomes (pain intensity, interference of pain, pharmaceutical consumption) to existing treatment modalities in IPRP, the IPRP team acquires prerequisites to adapt advice and physical activity prescriptions and to evaluate set activity goals. The overall aim is twofold. First, the aim is to evaluate the feasibility of the subsequent registry-based randomised controlled clinical trial (R-RCT). Second, the aim is to prospectively evaluate the effectiveness of the eVIS-intervention as a supplement to IPRP on our defined primary (physical health) and secondary outcomes. METHODS AND ANALYSIS: In the R-RCT, recruitment of 400 patients with chronic pain will be performed at 15 IPRP units. A random allocation to either IPRP + eVIS or to control group that will receive IPRP only will be performed. Data from the initial 30 participants completing the study period (6 months) will be included in a pilot study, where key feasibility outcomes (recruitment, randomisation, implementation, treatment integrity, data collection procedure, preliminary outcome measures) will be evaluated. Outcome variables will be extracted from the web application Pain And TRaining ON-line (PATRON) and from six national registries. Multivariate statistics and repeated measure analyses will be performed. Quality-adjusted life years and incremental cost-effectiveness ratio will be calculated for cost-effectiveness evaluation. ETHICS/DISSEMINATION: The Swedish Ethics Review Board granted approval (Dnr 2021/02109). Results will be disseminated through peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05009459. Protocol V.1.

Impact of a culturally tailored parenting programme on the mental health of Somali parents and children living in Sweden: a longitudinal cohort study.

OBJECTIVES: This study aimed to evaluate the long-term impact (3-year follow-up) of a culturally tailored parenting support programme (Ladnaan) on the mental health of Somali-born parents and their children living in Sweden. METHODS: In this longitudinal cohort study, Somali-born parents with children aged 11-16 were followed up 3 years after they had participated in the Ladnaan intervention. The Ladnaan intervention comprises two main components: societal information and the Connect parenting programme delivered using a culturally sensitive approach. It consists of 12 weekly group-based sessions each lasting 1-2 hours. The primary outcome was improved mental health in children, as measured by the Child Behaviour Checklist (CBCL). The secondary outcome was improved mental health in parents, as measured by the General Health Questionnaire-12. Data were collected from the parent's perspective. RESULTS: Of the 60 parents who were originally offered the intervention, 51 were included in this long-term follow-up. The one-way repeated measures (baseline to the 3-year follow-up) analysis of variance for the CBCL confirmed maintenance of all the treatment gains for children: total problem scores (95% CI 11.49 to 18.00, d=1.57), and externalising problems (95% CI 2.48 to 5.83, d=0.86). Similar results were observed for the parents' mental health (95% CI 0.40 to 3.11, d=0.46). CONCLUSION: Positive changes in the mental health of Somali-born parents and their children were maintained 3 years after they had participated in a parenting support programme that was culturally tailored and specifically designed to address their needs. Our findings highlight the long-term potential benefits of these programmes in tackling mental health issues in immigrant families. TRIAL REGISTRATION NUMBER: NCT02114593.

The value of interdisciplinary treatment for sickness absence in chronic pain: A nationwide register-based cohort study.

BACKGROUND: Interdisciplinary treatment (IDT) is an internationally recommended intervention for chronic pain, despite inconclusive evidence of its effects on sickness absence. METHODS: With data from 25,613 patients in Swedish specialist healthcare, we compared sickness absence, in the form of both sick leave and disability pensions, over a 5-year period between patients either allocated to an IDT programme or to other/no interventions (controls). To obtain population-average estimates, a Markov multistate model with theory-based inverse probability weights was used to compute both the proportion of patients on sickness absence and the total sickness absence duration. RESULTS: IDT patients were more likely than controls to receive sickness absence benefits at any given time (baseline: 49% vs. 46%; 5-year follow-up: 36% vs. 35%), and thereby also had a higher total duration, with a mean (95% CI) of 67 (87, 48) more days than controls over the 5-year period. Intriguingly, sick leave was higher in IDT patients (563 [552, 573] vs. 478 [466, 490] days), whereas disability pension was higher in controls (152 [144, 160] vs. 169 [161, 178] days). CONCLUSION: Although sickness absence decreased over the study period in both IDT patients and controls, we found no support for IDT decreasing sickness absence more than other/no interventions in chronic pain patients. SIGNIFICANCE: In this large study of chronic pain patients in specialist healthcare, sickness absence is compared over a 5-year period between patients in an interdisciplinary treatment programme and other/no interventions. Sickness absence decreased over the study period in bothgroups; however, there was no support forthat it decreased more with interdisciplinary treatment than alternative interventions.

Predictors of Sickness Absence in a Clinical Population With Chronic Pain.

Chronic pain-related sickness absence is an enormous socioeconomic burden globally. Optimized interventions are reliant on a lucid understanding of the distribution of social insurance benefits and their predictors. This register-based observational study analyzed data for a 7-year period from a population-representative sample of 44,241 chronic pain patients eligible for interdisciplinary treatment (IDT) at specialist clinics. Sequence analysis was used to describe the sickness absence over the complete period and to separate the patients into subgroups based on their social insurance benefits over the final 2 years. The predictive performance of features from various domains was then explored with machine learning-based modeling in a nested cross-validation procedure. Our results showed that patients on sickness absence increased from 17% 5 years before to 48% at the time of the IDT assessment, and then decreased to 38% at the end of follow-up. Patients were divided into 3 classes characterized by low sickness absence, sick leave, and disability pension, with eight predictors of class membership being identified. Sickness absence history was the strongest predictor of future sickness absence, while other predictors included a 2008 policy, age, confidence in recovery, and geographical location. Information on these features could guide personalized intervention in the specialized healthcare. PERSPECTIVE: This study describes sickness absence in patients who visited a Swedish pain specialist interdisciplinary treatment clinic during the period 2005 to 2016. Predictors of future sickness absence are also identified that should be considered when adapting IDT programs to the patient's needs.

Wrist-Worn Activity Trackers in Laboratory and Free-Living Settings for Patients With Chronic Pain: Criterion Validity Study.

BACKGROUND: Physical activity is evidently a crucial part of the rehabilitation process for patients with chronic pain. Modern wrist-worn activity tracking devices seemingly have a great potential to provide objective feedback and assist in the adoption of healthy physical activity behavior by supplying data of energy expenditure expressed as metabolic equivalent of task units (MET). However, no studies of any wrist-worn activity tracking devices' have examined criterion validity in estimating energy expenditure, heart rate, or step count in patients with chronic pain. OBJECTIVE: The aim was to determine the criterion validity of wrist-worn activity tracking devices for estimations of energy expenditure, heart rate, and step count in a controlled laboratory setting and free-living settings for patients with chronic pain. METHODS: In this combined laboratory and field validation study, energy expenditure, heart rate, and step count were simultaneously estimated by a wrist-worn activity tracker (Fitbit Versa), indirect calorimetry (Jaeger Oxycon Pro), and a research-grade hip-worn accelerometer (ActiGraph GT3X) during treadmill walking at 3 speeds (3.0 km/h, 4.5 km/h, and 6.0 km/h) in the laboratory setting. Energy expenditure and step count were also estimated by the wrist-worn activity tracker in free-living settings for 72 hours. The criterion validity of each measure was determined using intraclass and Spearman correlation, Bland-Altman plots, and mean absolute percentage error. An analysis of variance was used to determine whether there were any significant systematic differences between estimations. RESULTS: A total of 42 patients (age: 25-66 years; male: 10/42, 24%; female: 32/42, 76%), living with chronic pain (duration, in years: mean 9, SD 6.72) were included. At baseline, their mean pain intensity was 3.5 (SD 1.1) out of 6 (Multidimensional Pain Inventory, Swedish version). Results showed that the wrist-worn activity tracking device (Fitbit Versa) systematically overestimated energy expenditure when compared to the criterion standard (Jaeger Oxycon Pro) and the relative criterion standard (ActiGraph GT3X). Poor agreement and poor correlation were shown between Fitbit Versa and both Jaeger Oxycon Pro and ActiGraph GT3X for estimated energy expenditure at all treadmill speeds. Estimations of heart rate demonstrated poor to fair agreement during laboratory-based treadmill walks. For step count, the wrist-worn devices showed fair agreement and fair correlation at most treadmill speeds. In free-living settings; however, the agreement for step count between the wrist-worn device and waist-worn accelerometer was good, and the correlation was excellent. CONCLUSIONS: The wrist-worn device systematically overestimated energy expenditure and showed poor agreement and correlation compared to the criterion standard (Jaeger Oxycon Pro) and the relative criterion standard (ActiGraph GT3X), which needs to be considered when used clinically. Step count measured with a wrist-worn device, however, seemed to be a valid estimation, suggesting that future guidelines could include such variables in this group with chronic pain.

The Context Matters: A Retrospective Analysis of Life Stage at Chronic Pain Onset in Relation to Pain Characteristics and Psychosocial Outcomes.

BACKGROUND: Developmental life stage at chronic pain onset differs among chronic pain patients. Although pain affects multiple life domains, it is unknown whether the timing of chronic pain onset relates to pain characteristics and psychosocial outcomes. The purpose of this retrospective study was to investigate differences in pain characteristics and psychosocial outcomes in patients at different developmental life stages at chronic pain onset. METHODS: Cross-sectional baseline data from the Swedish Quality Registry for Pain Rehabilitation (2009 to 2016) were used, selecting the middle-aged patients (45-65 years, n=6225) reporting chronic nonmalignant pain. Patients were categorized into three groups, depending on their developmental life stage at chronic pain onset: early onset (age ≤30 years), intermediate onset (age 31-45 years), and late onset (age ≥46 years). Pain characteristics and psychosocial outcomes were assessed with validated self-reported measures. RESULTS: One-way MANCOVA indicated differences in number of pain locations and psychosocial outcomes among the groups. Post hoc analysis showed differences in the trends for how groups differed on outcome domains. Overall, patients with earlier chronic pain onset showed significantly poorer psychosocial outcomes and more spreading of pain. CONCLUSION: Developmental life stage at chronic pain onset is associated with different pain outcomes. Pain onset early in life is linked to worse outcomes in multiple domains, pointing to a need for identifying these patients early.

What Is the Effectiveness of Different Duration Interdisciplinary Treatment Programs in Patients with Chronic Pain? A Large-Scale Longitudinal Register Study.

Chronic pain is a leading cause of disability globally. Interdisciplinary multimodal pain rehabilitation (IMPR) targets pain with a bio-psycho-social approach, often delivered as composite programs. However, evidence of optimal program duration for the rehabilitation to succeed remains scarce. This study evaluated the effectiveness of different duration IMPR-programs-using within- and between-effects analyses in a pragmatic multicenter register-based controlled design. Using the Swedish Quality Registry for Pain Rehabilitation, data from fifteen clinics specialized in chronic pain rehabilitation across Sweden were retrieved. Participants were patients with chronic musculoskeletal pain who had taken part in short (4-9 weeks; n = 924), moderate (10 weeks; n = 1379), or long (11-18 weeks; n = 395) IMPR programs. Longitudinal patient-reported outcome data were assessed at baseline, post-intervention, and at a 12-month follow-up. Primary outcomes were health-related quality of life, presented as perceived physical and mental health (SF-36). Secondary outcomes included the Hospital Anxiety and Depression Scale (HADS), pain intensity (NRS 0-10), the Multidimensional Pain Inventory (MPI), and perceived health (EQ-5D). Overall, all groups showed improvements. No clinically important effect emerged for different duration IMPR. In conclusion, while our results showed that patients following IMPR report improvement across a bio-psycho-social specter, a longer program duration was no more effective than a shorter one.

Prognostic factors for improved physical and emotional functioning one year after interdisciplinary rehabilitation in patients with chronic pain: Results from a national quality registry in Sweden.

OBJECTIVE: To investigate prognostic factors for physical and emotional functioning following interdisciplinary multimodal pain rehabilitation, by targeting patients' baseline characteristics and health measures. METHODS: A prospective cohort of 2,876 patients from 38 specialist clinics across Sweden, who were completing interdisciplinary multimodal pain rehabilitation programmes, was followed through the Swedish Quality Registry for Pain Rehabilitation, from initial assessment to 12-month follow-up. Using logistic regression, baseline data were regressed to predict improvement in Physical functioning and Emotional functioning, fused by principal component analyses using the 36-item Short Form Health Survey (SF-36) and the Hospital Anxiety and Depression Scale (HADS). RESULTS: Employment status emerged as having the largest effect sizes in both Physical functioning and Emotional functioning; Working: odds ratio (OR) 2.05 (95% confidence interval (95% CI) 1.64-2.56) and OR 1.59 (95% CI 1.27-1.98), respectively. Strong beliefs in restored health, better initial emotional health, lower levels of pain and pain interference, and younger age all predicted Physical functioning. European origin, higher levels of general activity, and sense of life control all predicted Emotional functioning. Worse initial physical and emotional health predicted the corresponding dependent outcomes. CONCLUSION: Employment was consistently found to be an important prognostic factor, suggesting the significance of avoiding delay in interdisciplinary multimodal pain rehabilitation. A positive treatment expectancy was of importance. In general, multidimensional measures indicated that better initial status was more favourable; however, inconsistency implies a complex prognostic picture.

Psychometric properties of Short Form-36 Health Survey, EuroQol 5-dimensions, and Hospital Anxiety and Depression Scale in patients with chronic pain.

Recent research has highlighted a need for the psychometric evaluation of instruments targeting core domains of the pain experience in chronic pain populations. In this study, the measurement properties of Short Form-36 Health Survey (SF-36),EuroQol 5-dimensions (EQ-5D) and Hospital Anxiety and Depression Scale (HADS) were analyzed within the item response-theory framework based on data from 35,908 patients. To assess the structural validity of these instruments, the empirical representations of several conceptually substantiated latent structures were compared in a cross-validation procedure. The most structurally sound representations were selected from each questionnaire and their internal consistency reliability computed as a summary of their precision. Finally, questionnaire scores were correlated with each other to evaluate their convergent and discriminant validity. Our results supported that SF-36 is an acceptable measure of 2 independent constructs of physical and mental health. By contrast, although the approach to summarize the health-related quality of life construct of EQ-5D as a unidimensional score was valid, its low reliability rendered practical model implementation of doubtful utility. Finally, rather than being separated into 2 subscales of anxiety and depression, HADS was a valid and reliable measure of overall emotional distress. In support of convergent and discriminant validity, correlations between questionnaires showed that theoretically similar traits were highly associated, whereas unrelated traits were not. Our models can be applied to score SF-36 and HADS in chronic pain patients, but we recommend against using the EQ-5D model due to its low reliability. These results are useful for researchers and clinicians involved in chronic pain populations because questionnaires' properties determine their discriminating ability in patient status assessment.

Labour Q1 pain - poorly analysed and reported: a systematic review.

BACKGROUND: Modelling and analysing repeated measures data, such as women's experiences of pain during labour, is a complex topic. Traditional end-point analyses such as t-tests, ANOVA, or repeated measures [rANOVA] have known disadvantages. Modern and more sophisticated statistical methods such as mixed effect models provide flexibility and are more likely to draw correct conclusions from data. The aim of this study is to study how labour pain is analysed in repeated measures design studies, and to increase awareness of when and why modern statistical methods are suitable with the aim of encouraging their use in preference of traditional methods. METHODS: Six databases were searched with the English language as a restriction. Study eligibility criteria included: Original studies published between 1999 and 2016, studying pregnant women in labour with the aim to compare at least two methods for labour pain management, with at least two measurements of labour pain separated by time, and where labour pain was analysed. After deduplication, all records (n = 2800) were screened by one of the authors who excluded ineligible publication types, leaving 737 records remaining for full-text screening. A sample of 309 studies was then randomly selected and screened by both authors. RESULTS: Among the 133 (of 309) studies that fulfilled the study eligibility criteria, 7% used mixed effect models, 20% rANOVA, and 73% used end-point analysis to draw conclusions regarding treatment effects for labour pain between groups. The most commonly used end-point analyses to compare groups regarding labour pain were t-tests (57, 43%) and ANOVA (41, 31%). We present a checklist for clinicians to clarify when mixed effect models should be considered as the preferred choice for analysis, in particular when labour pain is measured. CONCLUSIONS: Studies that aim to compare methods for labour pain management often use inappropriate statistical methods, and inaccurately report how the statistical analyses were carried out. The statistical methods used in analyses are often based on assumptions that are not fulfilled or described. We recommend that authors, reviewers, and editors pay greater attention to the analysis when designing and publishing studies evaluating methods for pain relief during labour.