Definitions
BCG VACCINE
A PAL caller was defined as a parent who remained in the trial for at least 3 months (completed at least one of the 3-monthly questionnaires) and who called the PAL at least once during the first 2 years of their participation in the trial. A PAL non-caller was defined as a parent who remained in the trial for at least 3 months (completed at least one of the 3-monthly questionnaires) but who did not call the PAL. Parents who called exclusively with questions about the trial (including BCG vaccine injection site concerns) were defined as non-callers, and these calls were not included in the analysis. The principal concern was determined as the initial symptom discussed during the call, with other symptoms listed as additional concerns.