Table 3

Study outcomes in the PRINCIPLE trial

Primary outcome measuresData sourceTimepoint(s)
Time to recovery defined as the first instance that a participant reports feeling recovered from possible COVID-19Patient or study partner report.Within 28 days.
Hospital admission or deathPatient or study partner self-report and medical record review.Within 28 days.
Secondary outcomes
Duration of severe symptoms measured through daily diarySelf-report using online diary or telephone call/text.Daily online diary or telephone/text at days 7, 14 and 28 if no online data received.
Patient-reported illness severity
Number of contacts with the health servicesParticipant of study partner report using online diary, or telephone call/text and medical record review in primary care and hospital care.Daily online diary or telephone/text at days 7, 14 and 28 if no online data received
primary care and hospital records.
Additional antibiotic use
Hospital assessment without admission
Oxygen administration
Intensive care unit admission
Mechanical ventilation
(5–8 allows for an estimation of a version of the WHO Clinical Progression Ordinal Scale)
Duration of hospital admission
WHO-Five Well-Being IndexWHO-Five Well-Being Index.Baseline and days 14 and 28 either via online diary or telephone
To determine if effects are specific who test positive for SARS-CoV-2Swab results and optional serology for SARS-CoV-2 to determine an ‘Intention to Treat Infected’ group within the overall cohort for sub analysis.Swabs from enrolment and/or day 5. Convalescent serology.
Qualitative substudy
Patient experiences of consulting, being tested and taking (trial) medication for possible COVID-19Telephone interview with participant.After 28 days.
To explore healthcare professionals’ views of taking part in research during pandemicsTelephone interview with healthcare professional.At least 2 months after practice started recruiting.