Outcome variable and exposure variables
Participants were asked to indicate their frequency of use of exercise prescription in patient care (‘never’, ‘rarely’, ‘sometimes’, and ‘often’) – the outcome variable. The outcome variable was dichotomized to ‘not often’ (combining never, rarely and sometimes) or ‘often’24. The exposure variables were the practitioner and practice characteristics described in the Questionnaire section above. Variables with frequency or Likert-type responses were dichotomized for the analysis (often and not often (‘never’, ‘rarely’, ‘sometimes’) and attitude (definitely and not definitely(‘no’, ‘unsure’, ‘maybe’)). Age, average patient numbers per week, average patient care hours per week and years in clinical practice were analysed as continuous variables. All other variables included in our analysis are reported in binary form (yes/no).