Fig. 2.

Study design. i AAV diagnosis (cohorts 1 and 2). ii AAV relapse (cohort 2). i CW-D-UVB at diagnosis was calculated using the participant’s location and date of symptom onset if known, or the date of diagnosis minus 77 days. Seventy-seven days represents the undefined prodromal period [36] informed by the RKD registry analysis (see supplementary material). ii In this prospective n-of-1 component, each participant was a ‘case’ during period(s) of disease relapse and a ‘control’ during period(s) of remission [37]. The case window started at the date of relapse diagnosis minus 30 days (to account for the diagnostic delay) and ended 135 days later (see Additional file 1: Supplementary Methods). To improve the statistical power, 5 control dates were identified per patient, where possible