Materials and methods
The Heaf test was performed in accordance with BTS guidelines. Initially it was not anticipated that there (1) would be / would have been / was a need to offer BCG vaccinations on site to clients (i.e. homeless people) as it was assumed that, like the general population, only a small minority would have / would have had / had negative Heaf tests without BCG scars. This meant that at the beginning of the study, a number of Heaf tests (3) would be performed / would have been performed / were performed on clients without recording their BCG status.