Incentives vs outreach workers for latent tuberculosis treatment in drug users

Drug users are at increased risk for latent tuberculosis infection (LTBI) and also at increased risk for noncompletion of medication regimens for treatment of LTBI or tuberculosis disease. Directly observed therapy (DOT) provided by outreach workers, the use of incentives, or both have been suggested as a means to increase adherence.

To compare the independent and combined effects of monetary incentives and outreach worker provision of DOT for LTBI treatment in a sample of active drug users.

The research design was a randomized controlled trial in a community outreach program setting. Participants consisted of a volunteer sample of 163 active injection drug and crack cocaine users placed on twice weekly DOT. Condition 1 of the interventions consisted of provision of DOT by an outreach worker at a location chosen by the participant (active outreach) and a $5 per visit incentive. Condition 2 was comprised of active outreach with no monetary incentive, and Condition 3, provision of DOT at the study community site and a $5 per visit incentive. The main outcome measures were percentage of medication taken as prescribed and completion of medication regimen.

The percentage of prescribed medication taken was higher for those who received incentives, either with (71%) or without (68%) active outreach, compared to those who received active outreach alone (13%). Only 4% of participants assigned to Condition 2 completed treatment, compared to 53% of Condition 1 participants, and 60% of Condition 3 participants.

Monetary incentives were clearly superior to active outreach. Active outreach in combination with monetary incentives did not increase adherence over incentives alone.