Qualitative study
We conducted an exploratory qualitative substudy examining participant accounts. A topic guide (
Participants who consented to contact for qualitative research and reported at least one harm type were invited to interviews. One experiencing a false negative interviewed in a different SELPHI studyInterviews (June to August 2020) were conducted over Zoom and by telephone (because of COVID-19 restrictions) by the first and second authors, audio recorded and transcribed verbatim. Participants were given £30.Analysis (conducted using QSR NVivo V.12) followed a narrative approach. Participant accounts were treated as self-contained stories, and elements coded based on position within the narrative (eg, initial explanation, contributing features, critical point, resolution). Results were assessed for clarity/coherence by TCW, EJN, PW, AR and FB. As this study was primarily exploratory, we did not attempt to assess saturation.This study involves human participants and was approved by the University College London (ref: 9233/001) and the London School of Hygiene & Tropical Medicine (ref: 17985) research ethics committees. Participants gave informed consent to participate in the study before taking part.