A financial incentive for using an app designed for adults with attention-deficit/hyperactivity disorder (ADHD) resulted in a 100% adoption rate of the FOCUS ADHD app, according to a study published online in European Psychiatry.

“User engagement has proved to be a key element in determining the effectiveness of digital interventions, and here we show that financial incentives improved engagement,” wrote corresponding author Luiz Roberto Carvalho of the Institute of Psychiatry, Faculty of Medicine of the São Paulo, São Paulo, Brazil, and study coauthors. “Indeed, registrations of medication intake were significantly higher in the app + discount group compared with the app group, especially during the early phase of the trial.”

The study randomized 73 adults with ADHD in Brazil to 1 of 3 treatment groups over 3 months: (1) pharmacological treatment as usual; (2) treatment as usual plus the app (app group); and (3) treatment as usual plus the app plus a discount on ADHD medication (app + discount group). Researchers were interested in whether the app improved medication treatment adherence and improved patient knowledge of ADHD, as well as whether a financial incentive for app use affected engagement.

The study found no significant difference in treatment adherence, as assessed by a medication possession ratio (MPR), between the three groups. However, the MPR for each of the three groups in the study was above 100%, researchers pointed out.

“One possibility is that our study parameters, including weekly calls to participants from research assistants as well as scheduled assessments with the study psychiatrist, might have led to an inflated MPR in all groups,” researchers wrote. “Furthermore, MPR does not guarantee that the prescribed and dispensed medication was taken in the correct manner by the patient.”

When investigators focused on the 2 groups using the app, they found the app + discount group tracked medication intake more often than the app group during the early phase of the trial, when financial incentives were in place. Furthermore, the financial incentive was associated with a 100% app adoption rate compared with 75% for the app group.

Users of the app rated its usability and quality positively, the study found. Participants’ ADHD knowledge scores were high at baseline and did not increase significantly with app use.

“[F]or those using the app, evidence of increased medication intake registrations in the group that received a discount on their medication offers initial evidence supporting the utility of combining financial incentives with mobile health solutions to increase treatment adherence,” researchers wrote. “These data, together with prior evidence showing that app use can increase treatment adherence, call for future pragmatic trials designed to evaluate the effectiveness of the current proposed mobile health solution in real-life routine practice conditions.”