Eligibility and exclusion criteria, according to the Interim Clinical Commissioning Policy (published on 24 February 2022),12 for outpatients with covid-19 and their use in the present study
| Criteria | Criteria applied in present study* |
| Eligibility criteria | |
| SARS-CoV-2 infection was confirmed by PCR testing or by lateral flow test (registered via gov.uk or NHS 119) | Positive PCR or positive lateral flow SARS-CoV-2 test in the Second Generation Surveillance System (according to NHS Digital’s tests rule set logic,8 patients with a previous positive SARS-CoV-2 within the past 30 days were excluded; in addition, all patients admitted to the hospital 30 days before a positive test with a covid-19 diagnosis were excluded) |
| With covid-19 symptoms and showing no signs of clinical recovery | Not possible† |
| Patient was a member of a high risk group | See box 1 and supplementary material table S1, definitions of high risk groups and group names are based on published definitions and names by NHS Digital on 24 December 2021,10 unless otherwise noted |
| Exclusion criteria | |
| Requirement for hospital admission for covid-19 | Not possible (people in hospital on the day of their positive test were excluded) |
| New supplemental oxygen requirement specifically for the management of covid-19 symptoms | Not possible |
| Known hypersensitivity reaction to the active substances or to any of excipients of the drug treatments (described below) as listed in their respective summary of product characteristics | Not possible |
Earlier versions of the policy had some minor differences but this version was applied to the whole study period.
*Patients who received treatment (described below) were also included in the population even if they were not identified as meeting these criteria.
†It was only possible to identify whether the patient’s positive test had a symptomatic flag, but not possible to identify whether symptoms developed later; therefore, the symptomatic flag was used in a sensitivity analysis rather than within inclusion criteria.
PCR, polymerase chain reaction.