Table 1 Content of the baseline postal questionnaire

Quality of life

EuroQOL (EQ-5D) [31]

Five dimension descriptive system (today)

Perceived general health

MOS Short Form-36 (SF-36) version 2 [32]

36-items covering eight health domains (past 4 weeks)

Anxiety and depression

Hospital anxiety and depression scale [33]

Anxiety and depression sub-scales (past week)

Depression Screening questions for primary care [34]

Low mood/anhedonia in the last month

Bodily pain

Location: Self-completed manikin

"In the past 4 weeks, have you had pain that has lasted for one day or longer in any part of your body?"

Current pain severity [35]

0-10 NRS with verbal anchors (no pain, pain as bad as can be)

Episode duration [36]

<3 months, 3-6 months, 7-12 months, 1-2 years, 3-5 years, 6-10 years, 10+ years

Clinical triage and prioritisation tools

Patient-completed Salisbury score

6-item triage tool for musculoskeletal problems referred from primary care

PROG-RES tool [27]

7-item prognostic tool for musculoskeletal pain in primary care

Modified STarT Back screening tool [28]

7-item modified screening tool for musculoskeletal prognostic indicators including 5-item psychosocial subscale (past 2 weeks)

Knee pain

Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) [37]

Pain (0-20), stiffness (0-8), physical functioning (0-68)

Healthcare utilisation for musculoskeletal problems

Consultations

GP, hospital doctor, practice nurse, district nurse, physiotherapist, osteopath, other

Investigations/treatment

Medication use

Analgesics, NSAIDs, opiates, natural remedies, glucosamine, chondroitin

Occupational characteristics

Job title/type of work for most of working life

Current employment status

Working full-time/part-time, Employed but off-sick for < 6 months, Looking after home/children, Not working for > 6 months due to joint/back problem, Fully retired, Early retirement due to joint/back problem, Student

Work absence during last 6 months due to joint/back problems

Yes/No

Current work status

Doing usual job, working fewer hours, doing lighter duties, paid/unpaid sick leave

Stanford presenteeism scale (SPS-6) [38]

6-items concerning Health Status and Employee Productivity (5-point Likert scale)

Effect of joint/back problems on productivity

0-10 NRS with verbal anchors (no effect, completely prevented me from working)

Demographic characteristics

Date of birth, gender

Marital status

Married, separated, divorced, widowed, cohabiting, single

Living arrangements

Alone, not alone

Anthropometric data

Self-reported height

Self-reported weight

Lifestyle characteristics

Smoking status

Never, previously, currently

Alcohol intake

Daily, weekly, monthly, yearly, never