Table 1.

Recommendations for core outcome sets for clinical trial and/or effectiveness studies in chronic pain and back pain (table modified and adapted from Deckert et al. [25]).

Name of Initiative/Author	(a)Condition (b)Intervention (c)Scope of application (d)Location	Core Outcome Set -Domains-	Core Outcome Set -Measurement Instruments-	Stakeholders	Additional Comments
ICF Core sets for low back pain Cieza et al. 2004 [19]	(a)Low back pain (b)Not reported (c)Not reported (d)International	4 outcome domains body functions body structures activities and participation environmental factors Different number of second level categories for a comprehensive set and a brief set	ICF category system	Panel consisted of 18 experts (3 occupational therapists, 1 physical therapists, 14 physicians with various sub-specializations)	Formal decision-making and consensus process with systematic review, Delphi exercise and empirical data collection The both sets were recommended for validation only
ICF/IMMPACT for vocational rehabilitation Reneman et al. 2013 [20]	Musculoskeletal pain (subacut and chronic) Vocational rehabilitation Clinical research and clinical practice Regional (The Netherlands)	18 outcome domains (based on IMMPACT and ICF), e.g., Quality of life Physical functioning Pain intensity Emotional functioning Coping	12 measurement instruments such as: EuroQuol-5D Pain Disability Index (PDI); RAND 36-Item Health Survey Numerical Rating Scale (NRS) Work Reintegration Questionnaire (Distress sub-scale) Work Reintegration Questionnaire (Distress Avoidance and Persistence Sub-scale)	Preliminary core set was presented to 3 groups: Dutch Vocational rehabilitation center (n = 13; user, clinicians, management) Dutch pain rehabilitation development centers (n = 4; pain rehabilitation experts) Members of the consensus group (vocational rehabilitation) (n = 23; vocational rehabilitation experts)	Elaborate procedure to identify relevant outcome domains and measurement instruments: 1. Domains were identified according to ICF and IMMPACT recommendations 2. Domains were classified and judged by panel and authors (also according to the use in economic evaluation) 3. Instruments were identified for the included domains according to specific requirements of psychometric property
IMMPACT Turk et al. 2003 [16] Dworkin et al. 2005 [26]	Chronic pain No specific Clinical trials International	6 outcome domains (1)Pain (2)Physical functioning (3)Emotional functioning (4)Participant’s ratings of global improvement (5)Symptoms and adverse events, and (6)Participant’s disposition additional domains according to study aim: - role functioning—interpersonal functioning—pharmacoeconomic measures and health care utilization, - biological markers, - coping, - clinician or surrogate ratings of global improvement—neuropsychological assessments of cognitive and motor function, and—suffering and other end of life issues	(1)11 point (0–10) numerical rating scale of pain intensity (NRS) Usage of rescue analgesics Categorical rating of pain intensity (none, mild, moderate, severe) in circumstances in which numerical ratings may be problematic (2)Multidimensional Pain Inventory Interference Scale or Brief Pain Inventory Interference Items (3)Beck Depression Inventory (BDI) or Profile of Mood States (PMS) (4)Patient global assessment of change (PGIC) (5)Passive capture of spontaneously reported adverse events and symptoms and use of open-ended prompts (6)Detailed information regarding participant recruitment and progress through the trial, including all information specified in the CONSORT guidelines No measurement recommendations for the additional outcome domains	Domains [16] 27 participants with backgrounds in anesthesiology, biostatistics, clinical pharmacology, epidemiology, geriatrics, internal medicine, neurology, nursing, oncology, pediatric pain, physical medicine and rehabilitation, psychology, and rheumatology, all with research, clinical, or administrative expertise relevant to evaluating chronic pain treatment outcomes additionally representatives from the pharmaceutical industry and an attorney for specific expertise Measurement instruments [26] 35 participants from academia, governmental agencies, a self-help organization, and the pharmaceutical industry	Consensus process consisting of presence meeting and preselected clinical trials to identify relevant outcome domains Other issues have been published for assessing effectiveness in chronic pain, e.g.,: - Analyzing multiple endpoints [27] - Interpreting the clinical importance of group differences [28] - Interpreting the clinical importance of treatment outcomes [29] - Developing patient reported outcome measures [30] - COS for pediatric acute pain in clinical trials [31] #
IMMPACT Survey with patient representatives Turk et al. 2008 [24]	Chronic pain No specific Clinical trials International	19 outcome domains e.g.,: - sleep, - sexual activities, - ability to fulfill role function, - work ability, - several forms of activities (physical, homework, work, and social activities), - emotional wellbeing, weakness and fatigue, - cognitive impairment (e.g., concentrating and remembering)	Not reported	Patient representatives Preparing focus groups n = 31 Web survey n = 959	Preparing of relevant outcome domains via focus groups Validating via web survey
Low back pain Deyo et al. 1998 [23]	Low back pain No specific Clinical trials and other kinds of research (also routine care) International	6 outcome domains (1)Pain symptoms (2)(Physical) function (3)Well being (4)Disability (5)Disability (social role) (6)Satisfaction with care	For routine clinical use, quality improvement and as a component of formal research All domains form a set of six questions (six items), adapted from several instruments such as Short- Form 36 Questionnaire (SF-36(SF36), Roland and Morris disability scale (RMDS), EuroQuol and others For researchers (1)Bothersomeness or severity and frequency of low back pain and leg pain (2)Roland and Morris Disability scale (RMDS) or Oswestry Disability Questionnaire (ODQ) (3)Short- Form 12 Health Survey (SF-12) or EuroQuol (4)not mentioned (5)Days of work absenteeism, cut down activities, bed rest (6)single question on overall satisfaction (optional)	A multinational group of investigators	Consensus process not reported
Low back pain Bombardier 2000 [21]	Low back pain No specific Clinical and health policy setting International	5 outcome domains (1)Back specific function (2)Generic health status (3)Pain (4)Work disability (5)Patient satisfaction	(1) Oswestry Disability Questionnaire (ODQ) or Roland Morris Disability Questionnaire (RMDQ) (2) Short Form 36 (SF-36) (3) Bodily pain Scale (SF-36), optional Chronic pain grade (CPG) (4) Work status; #days off work and day of cut down work, # of day return to work (5) Patient satisfaction scale (PSS) and Satisfaction with treatment (one item)	Clinicians (physicians, psychologists, researchers experienced in pain medicine, outcome research and development of questionnaires)	non-formal consensus process not further described
Low back pain Chiarotto et al. 2015 [18]	Non-specific low back pain No specific Clinical trials International	4 outcome domains Physical functioning Pain intensity Health related quality of life * Number of deaths ** (for * and ** please refer to additional comments)	In preparation	Steering group consisting of members from four continents, including researchers, health care providers and patient representatives Panel was identified by systematic review about number of publications as an indicator for expertise, including representatives from health care researchers, health care providers, professionals working both as researchers and providers and patients with non-specific low back pain; n = 280	Three stage online Delphi and consensus exercise As an update of the former recommendation by Deyo et al. [23] * health related quality of life was not supported by the patient group.**Based on OMERACT 2.0 Filter framework [15]
VAPAIN Kaiser et al. 2015 [17]	Chronic pain Interdisciplinary multimodal pain therapy Effectiveness studies and daily record keeping International	In preparation	In preparation	Panel consists of 25 participants, 5 of each patient representatives, physicians, psychotherapists, physiotherapists with experience in interdisciplinary multimodal pain therapy and researches with methodological expertise in COS development and development of questionnaires	The VAPAIN process targets also towards the development and/or validation of measurement instruments for effectiveness studies and daily record keeping in MPT Multi-methodic consensus process with online exercises, structured consensus process and moderated face to face meeting Based on PROMIS framework [32]
WHO back pain initiative Ehrlich 2003 [22]	Low back pain No specific In all studies international (to all cultures)	Not specified	(1)Appropriate history and physical examination (2)Modified Schober Test of spinal mobility (3)Measurement of pain via visual analogue scale (4)Ostwestry disability questionnaire (ODQ) (5)Modified Zung Questionnaire (6)Modified somatic perception questionnaire	Not reported	Consensus process not reported

IMMPACT: Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials; ICF: International Classification of Functioning, Disability, and Health; VAPAIN: Validation and Application of a patient relevant core outcome set to assess effectiveness of multimodal pain therapy; # Recommended outcome domains for children and adolescents consist of Pain intensity, Global judgment of satisfaction with treatment, Symptoms and adverse events, Physical recovery, Emotional response, Economic factors.