Table 1.

Measures used in the questionnaire

Factor(s)	Description of measure and source
Age, gender, education, income, relationship status, occupation and living arrangements	Single-item questions from the New Zealand Census.28 Occupation grouped into professional (major levels 1–3), semiprofessional (levels 4 and 5) and trade/manual (levels 6–9) using New Zealand Standard Classification of Occupations29
Adequacy of household income	Single item regarding adequacy of total household income to meet everyday needs30
Material standard of living	Single item rating standard of living before injury.
Financial insecurity	Single item rating financial security in the next 10 years26
Repetitive hand movements, heavy lifting, painful/tiring body positions, standing and physical exertion	Set of five single items regarding amount of time spend doing physical task ranked on 4-point Likert scale ‘never’ to ‘all to ¾ of the time’31
Job strain, job support	Score using the Whitehall II study adaptation of Karasek’s job content model32
Job satisfaction	Single item rating overall job satisfaction/dissatisfaction31
Self-efficacy	General Self-Efficacy Scale, scale from 0 to 40, dichotomised into poor (score ≤25) and good (score >25)33
Optimism	Agreement with expectation of more good things happen than bad, dichotomised yes (agree and strongly agree) and no (strongly disagree, disagree and neutral)34
Prior depressive episode	Two items from Diagnostic and Statistical Manual III on depressed mode and loss of interest or pleasure in daily activities for at least 2 weeks in the year prior35
Hours and days worked per week	Single items asking number of hours or days worked in main job31
Type of contract	Combination of two items on employment status and, for employees only, the type of employment contract31
Multiple job holding	Single item asking if work only one paying job or more than one job31
Alcohol consumption	Score (0–12) identifying hazardous drinking patterns in the year prior using the brief Alcohol Use Disorders Identification Test36
Smoking status	Single item asking if smoke regularly.
Body mass index	Calculated using weight and height, categorised underweight/normal (≤25), overweight (25–29) and obese (≥30)
Physical exercise	Multiple questions ascertaining how many days over a 7-day period engaged in 15 min vigorous activity or 30 min moderate activity. Dichotomised into ≤4 or 5–7 days a week37
Sleep quantity	Single item identifying how many nights a week usually obtain at least 7 hours’ sleep
Self-assessment for health	Single item rating health in the 4 weeks prior to injury with 5-point Likert scale from excellent to poor38
Comorbidities	Single item asking if had any of a list of 21 specific chronic conditions lasting or expected to last more than 6 months39
Prior injury	Single item regarding any prior injuries that affect participant
Prior disability	Single item asking if had a health problem or condition lasting 6 months or more that caused difficulty with daily activities OR communication/socialising OR any other activity28
Injury nature and body region	12 binary Y/N variables indicating the presence of common nature and body region combinations were created using Accident Corporation (ACC) injury diagnosis data. Variables were created for lower extremity fracture; lower extremity open wound; lower extremity superficial injury; upper extremity fracture; upper extremity open wound; upper extremity superficial injury; head, neck and intercranial injury; head and neck superficial injury; spine dislocation, sprain or strain; upper extremity dislocation, strain or sprain; lower extremity dislocation, strain or sprain; and injury to other region
Work capacity	Single item scale assessing working capacity prior to injury from 1 total working capacity to 0 total inability to work40
Pain	Single item on pain or discomfort from the EuroQol-5 Dimension41
Assault	Single item regarding if injury was the result of an assault
Hospital admission	Single item asking if admitted to hospital for day or more
Anatomical severity—New Injury Severity Score (NISS)	Score created by mapping International Statistical Classification of Diseases, 10th Revision, injury codes to the Abbreviated Injury Scale (AIS) with the squares of the three highest AIS scores subsequently summed to form the NISS.42 43 The higher the score, the greater the anatomical injury severity. Scores were categorised NISS1-3, NISS4-6 and NISS>6.
Self-perceived threat to life	Single item rating if felt injury was a threat to life
Self-perceived threat of disability	Single item rating if felt injury was threat of severe longer term disability
Assessing health services	Single open-ended item assessing troubles getting to or contacting health services. Positive and mixed responses form the ‘no difficult access’ group, negative response ‘difficult access’ group
Work related	Single item regarding if injury was sustained while at work