GOALS for Adherence with Low-cost Incentives (GOALS): Findings From Year 1 of a Randomized Controlled Trial Evaluating the Impact of Small Airtime Incentives on ART Adherence Among Young People Living With HIV in Kampala, Uganda

For millions of people living with HIV, the path to health depends on a daily routine: taking medication that keeps the virus in check. This is not a matter of willpower alone; it is a logistical challenge that requires remembering to take a pill every single day, often for the rest of one's life. When people miss doses, the virus can rebound, leading to illness and the risk of passing the infection to others. This problem is especially acute for young people, whose lives are often filled with competing demands and whose brains are still developing the ability to plan for the distant future. In many parts of Africa, where the majority of people with HIV live, young people frequently struggle to stick to their treatment plans. The question facing doctors and researchers is how to help them stay on track. One promising idea comes from behavioral science: the concept of incentives. The theory suggests that offering a small, immediate reward for a good behavior can help people overcome the tendency to prioritize today's comfort over tomorrow's health. But there is a debate about how to set these rewards. Should the goal be a perfect score, like taking every single pill for a month, or should the goal be broken down into smaller, easier steps that build up over time?

In Kampala, Uganda, a team of researchers set out to answer this question with a large, carefully designed experiment involving 630 young people living with HIV. The study, known as GOALS, took place at Mildmay Hospital, a center that provides free care to thousands of patients. The researchers wanted to see if giving small amounts of mobile phone credit—known as airtime—could help young people take their medication more consistently. They were particularly interested in whether breaking the big goal of perfect adherence into smaller, quarterly targets would work better than asking everyone to aim for the same high standard right from the start. The team recruited participants aged 15 to 30 who had been taking their medication for at least three months but were not yet taking it consistently enough to be fully protected. To track exactly what was happening, every participant was given a special pillbox called a Wisepill. This device records the exact time the box is opened, sending that data to the researchers without requiring the patient to visit the clinic. This allowed the team to see the real story of medication taking, minute by minute, rather than relying on what patients said they did.

The participants were divided into four groups to test different approaches. One group received the usual standard of care, which included weekly text messages of encouragement but no rewards. The other three groups received the same encouraging messages plus the chance to win small amounts of airtime if they met specific goals. The first experimental group was given a fixed target: they had to reach 90 percent adherence every quarter to enter a prize draw. This mirrored how most existing programs operate, setting a high bar for everyone. The second group was given a different strategy. Their goals were assigned by the researchers based on where they started. If a participant was taking only half their pills, their goal for the first quarter was set at 60 percent, then 70 percent the next, and so on, building up to 90 percent by the end of the year. This approach was designed to make the goal feel reachable for those who were far behind. The third group was allowed to set their own goals. They chose their own targets for each quarter, with the only rule being that each new goal had to be at least as high as the last, and they had to reach 90 percent by the end of the year. This tested whether giving people control over their own targets would make them more motivated to succeed.

The results, observed over the course of a year, offered a clear picture of what works and what does not. The researchers found that the simple act of offering small airtime incentives did improve medication taking. When they looked at the final months of the study, the group that received no rewards had an average adherence rate of about 65 percent. In contrast, the group that had to hit the fixed 90 percent target every quarter saw their average adherence rise by nearly 6 percentage points compared to the control group. This was a statistically significant improvement, meaning it was very unlikely to have happened by chance. Even more telling was the number of people who reached the high standard of 90 percent or better. In the fixed-goal group, 7 percent more people reached this threshold than in the control group. This suggests that setting a clear, high bar and offering a reward for hitting it is an effective way to help young people achieve the level of adherence needed for long-term health.

Surprisingly, the strategies that broke the goal into smaller steps did not perform better than the simple fixed target. The group with the assigned, step-by-step goals did see a small improvement in their overall adherence, but it was not statistically significant compared to the control group. They were more likely to hit their specific quarterly targets, but this did not translate into a better final outcome than the group that just aimed for the big number from the start. Similarly, the group that set their own goals did not outperform the others. While allowing people to choose their own targets is often thought to increase commitment, in this case, it did not lead to superior results. The data showed that the fixed goal, which required everyone to aim for the same high standard, was the most effective design for getting the highest number of young people to the 90 percent mark.

The study also looked at who benefited most from these incentives. The researchers found that the fixed-goal approach was particularly helpful for those who started with the lowest levels of motivation or self-belief. For young people who felt unsure about their ability to take their medication, the clear structure of a fixed target combined with a small reward provided a boost that helped them succeed. The study did not find evidence that breaking goals into smaller pieces was necessary to help these individuals; in fact, the simple, uniform high target worked just as well, if not better, for the group as a whole. This challenges the idea that people with low adherence need a gentler, step-by-step approach to get started. Instead, it suggests that a straightforward, high standard supported by a small, immediate reward can be powerful enough to change behavior.

The implications of these findings are practical and immediate. In a setting where resources are limited, the ability to improve health outcomes with a low-cost intervention is invaluable. Mobile airtime is cheap, easy to distribute, and highly valued by young people in Uganda. The study demonstrates that programs can adopt a simple, fixed high-adherence target as the default approach, rather than trying to customize goals for every individual. This simplifies the work of health workers and removes the complexity of calculating different targets for different patients. While the study focused on the first year of treatment, the results provide strong evidence that small, low-cost incentives can be a reliable tool for helping young people stay healthy. The research confirms that when the goal is clear and the reward is tangible, young people are capable of rising to the challenge, even when the standard is high.