Table 4 Content of 3-year postal follow-up Health Survey questionnaire (Phase 1 and Phase 2 participants)

Section A: General health

Perceived general health

MOS SF 12 [33]

Physical and mental component summary scores

Physical function

MOS SF 36 [32]

Physical functioning sub-scale

Anxiety and depression

Hospital anxiety and depression scale [34]

Anxiety and depression sub-scales

Participation

Keele Assessment of Participation (KAP) [35, 73]

5-items assessing person-perceived, performance-based participation

Physical activity

Short-Form International Physical Activity Questionnaire (IPAQ) [36]

Frequency and duration of 4 activities performed during previous 7 days

Section B: Specific health problems

Hallux valgus

Self-completed line drawings [37]

5 line-drawings for each foot depicting increasing severity of hallux valgus

Co-morbidities

Falls, fractures, chest problems, heart problems, deafness, problems with eyesight, raised blood pressure, diabetes, stroke, cancer, liver disease, kidney disease, poor circulation, rheumatoid arthritis

Yes for any that apply

Intermittent claudication

Edinburgh Claudication Questionnaire [38]

Pain or discomfort in legs when walking, pain characteristics, pain location (leg manikin)

Bodily pain

Self-completed body manikin

In the past 4 weeks, have you had pain that has lasted for one day or longer in any part of your body? If yes, shade location of pain on manikin

Site-specific questions

Have you had any problems with your hands or pain in your hands/hips/knees/feet in the last year?

Section C: Foot pain

Foot pain characteristics

Side of pain

Both, right, left

Duration in past 12 months

< 7 days, 1-4 weeks, 1-3 months, 3+ months

Have you ever injured your foot badly enough to see a doctor about it?

No/right foot only/left foot only/both feet

Location: self-completed foot manikin [14]

In the past month, have you had any ache or pain that has lasted for one day or longer in your feet? If yes, shade location of pain on foot manikin

Foot pain, aching, stiffness in last month [39]

No days, few days, some days, most days, all days

Foot pain intensity in last month [40]

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

Complaint-specific functioning

Manchester Foot Pain and Disability Index [41]

19-items across four constructs: pain, function, appearance, work/leisure

Coping strategies for foot pain

Single-item coping strategies questionnaire [42]

0-6 NRS with verbal anchors (never do that, always do that)

Healthcare use

Medication use in last month

For foot pain, for other pain

Consultation with general practitioner in last 12 months for foot pain

Section D: Demographic/socioeconomic characteristics

Demographic characteristics

Date of birth

Gender

Marital status

Married, separated, divorced, widowed, cohabiting, single

Living arrangements

Alone, not alone

Anthropometric characteristics

Self-reported height

Self-reported weight

Socioeconomic characteristics

Current employment status

Employed, not working due to ill-health, retired, unemployed/seeking work, housewife, other

Current/recent job title

Free text

Current/recent job title of spouse

Free text

Adequacy of income [43]

Find it a strain to get by from week to week, have to be careful with money, able to manage without much difficulty, quite comfortably off

Additional questions for phase 2 participants only

Foot pain characteristics

Change in foot pain over past 3 years

Completely recovered, much better, better, no change, worse, much worse

Since your assessment 3 years ago, have you injured your foot badly enough to see a doctor about it?

No/right foot only/left foot only/both feet

Foot pain severity

Chronic Pain Grade [59]

6 questions (0-10 NRS) and 1 question (4 response options) giving grade I-IV

Symptom satisfaction [64]

5-point Likert scale (Very dissatisfied to Very satisfied)

Healthcare use

Use of services/treatments for foot pain in past 3 years

GP, physiotherapist, hospital specialist, acupuncture, podiatrist, chiropodist, drugs on prescription, foot injection, foot surgery, osteopath/chiropractor, other (specify)