Figure 1. Recruitment, Randomization, and Patient Flow.

Recruitment of 513 patients with idiopathic pulmonary fibrosis who were randomized to 2 therapeutic strategies in a 1:1 allocation ratio. Prior to randomization eligible patients and their physician were offered a preference for the co-trimoxazole (trimethoprim-sulfamethoxazole) or doxycycline stratum; the protocol specified co-trimoxazole in the absence of a selection.¹²

^aUnable to return to the treatment site in a timely fashion because of either the COVID-19 shutdown or scheduling difficulties.