Data Collection

A data collection procedure confers participant status when it informs a study outcome and involves researcher interaction with providers or collection of identifiable private provider information. Controls are frequency-matched to cases at a 1:1 ratio by age group, sex, and ethnicity. Provider behaviour data used only to monitor whether an intervention was delivered as planned are process or fidelity data rather than outcome data. Between-group differences will be assessed using t-tests for normally distributed data and Mann-Whitney U tests for non-normal data. Clinical history was self-reported except for diabetes and hypertension, which were objectively assessed. Most measures came from validated instruments and scale reliability was generally satisfactory to excellent. Hospitalisation data include postoperative pain management, pain scores, analgesic classification, length of stay, ICU stay, and wound status. Wave 6 used telephone-based structured clinical interviews to assess more than 20 psychiatric diagnoses under DSM-5 and ICD-10. Perioperative data include procedure time, console time, blood loss, pneumoperitoneum characteristics, device errors, and open conversions. Clin…