Table 3.

Outcomes and other measures

Primary outcome measure*
Self-reported pain	WOMAC (VAS) [28-31] pain subscale
Secondary outcome measure*	Measurement
Self-reported physical function, pain and stiffness	WOMAC (VAS) physical function and stiffness subscales [28-31], NPRS, mean and worst pain (past week, 3 months)
Depression, anxiety, sense of coherence, pain catastrophizing, kinesiophobia, self-efficacy, and life satisfaction	BDI-21 [34-37], BAI [38,39], 13-item SOC scale [40-46], PCS [47,48], TSK [49,50], PSEQ [51,52], 4-item LS scale [53-55]
Health-related quality of life and cost effectiveness	RAND-36 (SF-36) [56,57], 15D [58], QALY [58], OA-related sick leave, use of pain medication, knee OA-related health care visits, rehabilitation and pensions
GAC	GAC
Other measures	Measurement
Identifying risk for persistent pain	Örebro MPQ [59]
Major life events	Open question
Adherence	Attendance at meetings

*The primary end point for data analysis is 12 months. All outcome measures will be undertaken at baseline and after 3 and 12 months. WOMAC = Western Ontario and McMaster Osteoarthritis Index; NPRS = numeric pain rating scale; BDI-21 = 21-item Beck Depression Inventory; BAI = Beck Anxiety Index; SOC = sense of coherence; PCS = Pain Catastrophizing Scale; TSK = Tampa Scale for Kinesiophobia; PSEQ = Pain Self-Efficacy Questionnaire; LS = life satisfaction; RAND-36 = the RAND 36-item health survey; 15D = generic 15D instrument; QALY = quality-adjusted life years; OA = osteoarthritis; GAC = global assessment of change; MPQ = Musculoskeletal Pain Questionnaire.