Trial to Incentivise Adherence for Diabetes
Condition: Type 2 Diabetes Mellitus
MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 2
Study type: Interventional

Summary: 
      Type II diabetes is associated with a host of adverse and costly complications, including
      heart attacks, strokes, blindness, kidney failure, and severe neuropathy that may result in
      amputations. For those with diabetes, glycemic control is essential to minimize complications
      but many fail at being sufficiently adherent to their treatment. The investigators propose to
      test two incentive-based intervention strategies aimed at improving diabetes outcomes amongst
      patients with uncontrolled glycemic levels. The incentives are tied either to processes aimed
      at improving blood sugar levels (glucose testing, physical activity and medication adherence)
      or directly to the intermediary outcome (blood glucose in the acceptable range). While
      process incentives are likely to provide more motivation for treatment adherence, as these
      goals may be comparably easier to meet, these incentives only reward intermediary outcomes
      and it might be more effective to reward successfully achieving a health outcome directly.
    

Detailed description: 
      Type II diabetes is associated with a host of adverse and costly complications, including
      heart attacks, strokes, blindness, kidney failure, and severe neuropathy that may result in
      amputations. For those with diabetes, intensive glycemic control is essential to minimize
      complications. Medication adherence, weight loss, increased exercise and improved diet have
      all been shown to significantly improve glycemic control, resulting in improved health
      outcomes and lower medical costs, including a reduction in emergency department visits and
      hospitalizations. Yet, despite the significant health benefits associated with adherence to
      diet and exercise regimes and taking diabetes medications as prescribed, non-adherence to all
      three is a significant problem. One strategy to improve adherence and thus long term health
      outcomes is to provide a clearer short term benefit. For example, those with consistent
      evidence of adherence to an exercise or medication regimen could receive subsidies or
      incentives.

      Therefore, the investigators propose to test three theory-based intervention strategies aimed
      at improving diabetes outcomes amongst a population of uncontrolled patients (Haemoglobin
      A1c, HbA1c, levels of 8.0 or greater at baseline). The proposed 6-month study will randomise
      240 participants, 60 in the control arm and 90 in each incentivized arm from the Geylang
      Polyclinic. The first strategy does not involve incentives but includes a Diabetes
      Educational Program (DEP) to help the patient manage their condition. Included in the program
      are text messages to encourage participants to take their medications as prescribed and
      prompt good dietary and exercise practices. Subsequent strategies incorporate incentives as
      core components. The incentives are tied either to processes aimed at improving blood sugar
      levels (glucose testing, physical activity and medication adherence) or directly to the
      intermediary outcome (blood glucose in the acceptable range). While process incentives are
      likely to provide more motivation for treatment adherence, as these goals may be comparably
      easier to meet, these incentives only reward intermediary outcomes and it might be more
      effective to reward successfully achieving a health outcome directly. The investigators see
      this as an important empirical question that will be answered by our proposed trial. Another
      advantage of outcome incentives is that they are likely to be more cost-effective than
      process incentives as these incentives are only spent on results.

      Aims and hypotheses that will be tested:

        -  Aim 1A: To determine if adding financial incentives for diabetes management to a
           Diabetes Educational Program (DEP), which comprises text messaging and use of study
           devices to encourage patient medical adherence and prompt good dietary as well as
           exercise practices, is more effective at improving diabetes health outcomes compared to
           the DEP alone.

        -  Hypothesis 1A: The average reduction in HbA1c levels at 6 months will be greater for
           participants in the incentive arms compared to participants in the DEP arm.

        -  Aim 1B: To determine whether incentivising health outcome (self-monitored blood sugar
           within acceptable range) is more effective at improving diabetes health outcomes than
           incentivising intermediate processes (blood glucose testing, physical activity and
           medical adherence) aimed at improving the primary outcome.

        -  Hypothesis 1B: The average reduction in HbA1c levels at 6 months will be greater for
           participants in the health outcome incentive arm compared to participants in the
           processes incentive arm.

        -  Aim 2: To determine which intervention (i.e. incentivising processes or outcome) is more
           cost effective (incrementally) at achieving reductions in HbA1c levels at 6 months.

        -  Hypothesis 2: The Incremental Cost-Effectiveness Ratio (ICER) of the intervention
           incentivising health outcome will be greater than that of the intervention incentivising
           processes.

        -  Aim 3A: To determine whether adding financial incentives for diabetes management is more
           effective at improving treatment adherence (assessed based on whether self-monitored
           blood sugar falls within acceptable range) than incentivizing intermediate processes
           aimed at improving the primary outcome.

        -  Hypothesis 3A: The average increase in the proportion of medications and blood tests
           taken as prescribed and average number of daily steps at 6 months will be greater for
           participants in the incentive arms compared to participants in the DEP arm.

        -  Aim 3B: To determine whether incentivising treatment adherence (through assessing if
           self-monitored blood sugar falls within acceptable range) is more effective at improving
           treatment adherence than incentivising intermediate processes aimed at improving the
           primary outcome.

        -  Hypothesis 3B: The average increase in the proportion of medications and blood tests
           taken as prescribed and average number of daily steps at 6 months will be greater for
           participants in the outcome incentive arms compared to participants in the processes
           incentive arms.
    

Intervention name(s): Diabetes Educational Program (DEP); DEP + Process Incentive; DEP + Outcome Incentive
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Participants in this Arm will receive the Diabetes Educational Program (DEP), as required, which is part of usual care at the Polyclinic. It is delivered by a Health Counsellor at the point of diagnosis and focused education is provided during doctor visits for medication. The program at the Polyclinic comprises information on a series of diabetes-related issues.
The participant will receive the 2 or 3 study devices (patients will receive a glucometer if they do not already have one). The Site Study Coordinator will provide education on the use of the Fitbit Zip™ and the eCAP™. As part of usual care, patients who have difficulties with their glucometer will be referred to a Health Counsellor at the Polyclinic.; Participants will receive the DEP as required. In addition, participants will have the opportunity to earn financial incentives (in vouchers) for meeting specified goals:
SGD3.50 weekly for meeting Glucose testing goals: measuring blood glucose on three non-consecutive days each week.
SGD0.50 daily for Medication adherence: taking medications daily as prescribed, monitored by eCAP device. Assessed based on medication-taking times within specified time windows. Participants should be adherent at all specified mealtimes to be fully adherent for the day.
SGD1.00 daily for Regular Physical activity: taking 8,000 steps during the day as recorded by Fitbit.; Participants will receive the DEP as required. In addition, participants will have the opportunity to earn financial incentives (in vouchers) for recording glucose readings within the normal range (i.e. between 4 to 7mmols/L two before a meal) on 3 non-consecutive days within the week using the glucometer.
SGD 2 weekly if one glucose readings falls within the normal range,
SGD 7 weekly if two glucose readings fall within the normal range,
SGD 14 weekly if all three glucose readings fall within the normal range.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: Diabetes; Treatment medication adherence; Physical activity; Financial incentives; Outcome incentives; Process incentives; HbA1c