Use of incentives to increase compliance for TB screening in a population of intravenous drug users

SETTING: Intravenous drug users (IDUs) represent a high risk group for dual human immunodeficiency virus (HIV) and tuberculosis (TB) infection. Screen ing with TB skin testing has therefore been suggested in this group. Subjec ts' compliance for returning to have TB skin test results read is a major p roblem. In the setting of a needle exchange program we evaluated the role o f financial incentives to increase compliance. METHODS: We evaluated the role of giving a small financial incentive of Can $5 to subjects if they returned to have their purified protein derivative (PPD) skin test read. IDUs who had previously been skin-tested were compare d with IDUs drawn from a similar population who, prospectively, were offere d a financial incentive. RESULTS: During the initial period 558 subjects were evaluated and no incen tive was offered. During the second phase of the study 549 IDUs were assess ed but were also offered Can $5 if they returned to have their skin test re ad. Use of incentives increased compliance from 43% to 78% (P = 0.001). Dur ing the same period three active cases of TB were also diagnosed. CONCLUSIONS: We suggest that use of financial incentives can increase the r eturn of IDUs to have their skin tests read. Further studies are required t o assess the efficacy of follow-up interventions, especially the use of iso niazid chemoprophylaxis.