Figure 1
From: Falsification of home rapid antigen lateral flow tests during the COVID-19 pandemic
Tree diagram of the Crosswise model (Yu et al.36); Ļ represents the unknown prevalence of the behaviour of interest; p denotes the known prevalence of the non-sensitive question (the randomisation probability); option Aā=āYes (or No) to both questions; option Bā=āYes to one and No to the other, irrespective of which one.
