Effects of an incentive and education program on return rates for PPD test reading in patients with HIV infection

To determine the impact of a food voucher incentive and patient education program on compliance with tuberculin skin test (PPD, purified protein derivative) performance in HIV-infected adults, we analyzed return rates for PPD reading for patients at our urban HIV clinic. The groups studied included patients who received no intervention (controls), patients offered a food voucher incentive, and patients offered a food voucher and patient education intervention. Return rates for PPD reading were 96 (35%) of 272 for the control group, 111 (48%, p = 0.004) of 229 for the food voucher group, and 96 (61%, p < 0.0001) of 158 for the food voucher and patient education group. By univariate analysis, black patients (p = 0.01), males (p = 0.01), older patients (p = 0.04), city residents (p = 0.001), and injection drug users were more likely to return for PPD reading. By logistic regression, food voucher, food voucher plus education, city residence, and male sex were significantly associated with return for PPD reading. Two simple, inexpensive interventions were found to increase compliance with tuberculin skin test performance in HIV-infected adults. Additional interventions are required to achieve better rates of return for PPD reading.