Data collection
disability
At baseline, a short interviewer-administered questionnaire was completed, including demographic data and the 12-item WHODAS 2.0 (World Health Organization Disability Assessment Schedule 2.0), which is a generic assessment instrument developed by the WHO to measure health and disability (scale: 0 = no disability to 48 = high disability).Patients in the intervention group recorded their oxygen saturation in a paper diary three times a day for 14 days. After 14 days, participants reported their overall feeling of safety over the previous 2 weeks on a 0 (completely unsafe) to 100 (completely safe) visual analogue scale by phone.At the end of the 45-day follow-up period, participants completed the 12-item WHODAS 2.0 again and those in the control group were asked by phone if they had used a pulse oximeter at home after study enrolment. Healthcare utilisation was captured by retrieving patients’ primary care electronic health record data.