Table 1. INH Intake Reference Standard scoring system.

Component	Criteria needed for points	Points allocated
Directly observed INH intake	Patient ingested INH tablet	+1
BD BBL Taxo test	Blue-purple or green positive results	+2
Hospital records	Prescription of daily INH	+1
Patient self-report	Questionnaire score was at least 40 points	+1
Total points needed for positive INH intake classification		>2 pts