INcentives and ReMINDers to Improve Long-term Medication Adherence
Phase: NA
Conditions: HIV/AIDS
Sponsor: RAND

 
Title of the study 
INcentives and ReMINDers to Improve Long-term Medication Adherence (INMIND) 
 
Version and version date 
Version 3.1, 13 August 2024  
 
Principal Investigators list and address 
Lead Principal Investigator: Dr. Sebastian Linnemayr, RAND Corporation, 1776 Main St, 
90401 Santa Monica, CA, USA 
Telephone: +1-310.393.0411 ext 6734 
 
Site Principal Investigator: Dr. Barbara Mukasa, Mildmay Uganda 
P.O. Box 24985, Kampala; Uganda. 
Office: Tel: +256 312 210 200  
Mobile: +256772700816 
Email: barbara.mukasa@mildmay.or.ug 
 
Co-Investigators: 
Alina Ionela Palimaru, PhD MPP, RAND Corporation, 1776 Main Street, Santa Monica, CA 
90407, Telephone: 310-393-0411, ext. 7312 
 
Chad Stecher, College of Health Solutions, Arizona State University 500 N 3rd Street, Phoenix, 
AZ 85003, Telephone: +1-602-496-957 
 
Dr. Yvonne Karamagi, Mildmay Uganda, P.O. Box 24985, Kampala; Uganda. 
Telephone: +256 312 210 200  
 
 

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Introduction 
Antiretroviral therapy (ART) has transformed an HIV infection from a likely death sentence to a 
manageable chronic condition [1], but the efficacy of ART hinges on maintaining high (at least 
80-85%) mean medication adherence [2–4]. Globally, roughly 53% of people living with HIV 
(PLHV) have access to ART, but only 44% of PLHIV are virally suppressed [5]. In Sub-Saharan 
Africa, only a quarter of PLHV are virally suppressed [5], which results in avoidable cases of 
drug resistance [6] and death [7]. Structural (e.g., drug availability), social (e.g., stigma), and 
economic (e.g., distance to clinic, clinic fees) ART adherence barriers have been documented in 
the literature [8–10], but patient behavior has been identified as a key factor determining the 
lack of viral suppression [11]. Recent research has shown that mean ART adherence ranges 
from 60-80% in Uganda, and only 30-60% of patients achieve 85% adherence [12–14]. Thus, 
novel behavioral interventions are needed to help establish and maintain high ART adherence 
habits among PLHIV in Uganda.  
 
Daily habits (or routines) are a commonly reported strategy for maintaining high medication 
adherence among patients who successfully manage chronic diseases [15,16], but forming new 
routines is often difficult for patients to do on their own. According to recent psychology 
research, it takes approximately three months of repeatedly performing a daily behavior in 
response to the same contextual cue [17–20], as outlined in the Habit Formation Model in 
Figure 1a [21], before the behavior becomes routinized. Once routinized, the cognitive 
processes that govern the behavior move to neurological systems that operate non-consciously 
[22–25]. Additionally, behaviors that are routinized no longer require high intrinsic motivation to 
be carried out, and thus can enable even the most vulnerable ART treatment initiators, such as 
those with limited motivation, to maintain high long-term adherence.  
 
Figure 1: Duhigg’s (2013) habit formation model underlies the anchoring intervention strategy, which we 
propose to enhance in INMIND through incentives and reminders to successfully routinize ART 
adherence among HIV-patients. 
 

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One common intervention method for establishing new routines is to anchor the targeted 
behavior to an existing routine that acts as the contextual cue. For example, taking ART 
medication after brushing one’s teeth in the morning or after completing evening prayers. This 
method is often called Anchoring (Figure 1b), and has been shown to be an effective 
intervention for promoting physical activity routines [26], improving dietary routines [27], and 
maintaining smoking cessation [28]. However, these existing studies typically enrolled 
participants with high intrinsic motivation for the targeted behavior [29–33], and therefore hold 
little potential for real-life clinical situations where there is no extra support for individuals with 
low intrinsic motivation (as is typical for many patients in HIV care [34]). Moreover, less than half 
of participants in these existing studies successfully used their anchor and maintained the 
desired behavior in the long run [35]. 
 
Behavioral economic theory demonstrates the need for ongoing support during the time it takes 
to complete the routinization process and also provides proven intervention methods for 
delivering such support to enhance existing anchoring interventions. The behavioral economic 
biases of lack of salience of ART adherence (e.g., over time, more pressing needs of daily life 
dominate one’s attention and focus) and present bias (e.g., excessively undervaluing the future 
health benefits of one’s actions) help to explain why many people have trouble sticking to their 
healthy intentions [36,37]. Fortunately, behavioral economics also suggests two methods for 
countering these biases: 1. text messages that can be used to reinforce information provided at 
recruitment and to increase the salience of the anchoring routinization strategy, and 2. small 
behavioral economics-based incentives that have successfully changed a range of health 
behaviors by countering present bias [38–41]. Therefore, this study will test whether incentives 
for linking daily pill-taking to the timing of an existing routine behavior can establish and 
maintain high ART adherence routines in a feasible and scalable manner. 
 
Additionally, this intervention is being targeted to treatment initiators in order to leverage the 
‘fresh start’-effect [45], a period of heightened motivation and attention. ART adherence 
instructions are initially salient for treatment initiators, but over time they fade from attention. 
Among HIV-infected adults in Sub-Saharan Africa, forgetfulness is the most frequently reported 
adherence barrier to maintaining high long-term adherence [46,47]. Treatment initiators may 
therefore need subsequent support for adhering to the ART medication protocol until the 
behavior has been successfully routinized, which will be provided in the form of text messages 
and incentives. 

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We propose to test the intervention “INcentives and ReMINDers to Improve Long-term 
Medication Adherence” (INMIND) in a pilot, parallel group randomized controlled trial (RCT) at 
the Mildmay Uganda HIV clinic in Kampala, Uganda with two intervention groups and a control 
group using an even allocation ratio of 1:1:1 between the three study groups. All participants 
(including in the control group) will receive information about the importance of behavioral 
routines, as is part of the standard adherence counseling for treatment initiators at Mildmay 
Uganda and will create personalized ART adherence anchoring strategies. The first intervention 
group will additionally receive text message reminders of their anchoring strategy, and the 
second intervention group will receive both the text message reminders and small incentives 
conditional on taking ART pills within a time window that corresponds to participants’ 
personalized anchoring strategy. We hypothesize that the text message reminders and 
incentives will increase participants’ use of their anchoring strategy, and thus medication 
adherence will be better maintained after the intervention ends in our two intervention groups 
relative to the control group. We also expect to see stronger maintenance in the intervention 
group receiving both reminder messages and incentives than the intervention group receiving 
only reminder messages.  
 
Methods 
Ethics Approval 
This pilot RCT has been funded by the National Institutes of Mental Health in the United States 
(R34MH122331) and approved by the RAND Human’s Subjects Protection Committee (2020-
N0632), Mildmay Uganda Research Ethics Committee (MUREC) (0701-2021), as well as the 
Uganda National Council for Science and Technology (HS128ES). As of February 18, 2022, 
recruitment was completed. 
 
Study Design 
This study will use a three-armed randomized controlled trial (two intervention groups and one 
control group) with randomization at the individual level. The interventions will be administered 
for a period of three months from the baseline survey. During the intervention period, MEMS 
data readings will be collected monthly, wherein prize drawings for eligible participants in the 
Incentives group will be carried out. Since the population of interest are treatment initiators, the 
monthly study visits are expected to coincide with the monthly clinic visits as mandated for 

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newly diagnosed clients who are getting accustomed to ART treatment. During the post-
intervention period, the team will follow participants and continue MEMS data collection during 
the participants’ regular clinic visits (expected to be every month for the first six months post 
treatment initiation, and every one-to-three months thereafter) for a period of six months, 
bringing the total study period to nine months.  
 
Since the long-term goal of the study is viral suppression, viral load data will also be collected 
during the routine assessment. Viral load tests for treatment initiators are conducted after the 
first six months of ART initiation, and then switched to 12-month periods as per clinic and 
Ugandan Ministry of Health guidelines. Survey assessments will be administered at baseline, 
month three, and month nine for all participants. 
 
It is important to note that the pilot study is being preceded by a formative phase, and 
succeeded by an adaptation phase, both of which are geared towards collecting qualitative data 
pertaining to the overall design, feasibility, and acceptability of the interventions. The results of 
the formative phase will be used to adapt the pilot intervention materials and timeline prior to the 
intervention administration. The adaptation phase is expected to provide feedback on the 
mission critical parameters of the interventions, which would be utilized to mold the intervention 
in preparation for a full-scale randomized controlled trial. Figure 2 gives the timing of study 
activities. 
 
Study Sites 
The study will be performed at the Mildmay, Uganda, an HIV clinic in Kampala, Uganda. This 
clinic specializes in providing comprehensive HIV and AIDS prevention, care, and treatment 
services to over 105,000 HIV-infected patients. It offers integrated health services to a diverse 
population base; of the 15,000 patients served at the main site in Lweeza, 11% are children 
younger than 18 years, 65% are female, and 100% of patients are on ART. Mildmay also has 
well-established electronic medical records infrastructure, making it one of the growing number 
of facilities using electronic medical record systems in Uganda. 
 
Apart from the patient-facing work, Mildmay also provides technical assistance to organizations 
and governments, hosting training and educational courses for over 1,500 professionals per 
year. Further, the Mildmay Uganda laboratory is accredited by the South African National 
Accreditation System under ISO 15,189:2012, and specializes in virology and other tests. 

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Mildmay also has numerous ongoing research projects involving international researchers. It 
has a standing Community Advisory Board comprising of church leaders, elected councilmen, 
healthcare providers (external to Mildmay), and HIV client advocates.  
 
Sampling Strategy 
The objective of this study is to establish preliminary efficacy as well as acceptability and 
feasibility of the interventions. Consequently, 150 participants will be recruited from Mildmay’s 
main site for the pilot study. The sample will be representative of the patient population at 
Mildmay with a roughly 70:30 ratio of female to male clients.  
 
Electronic medical records and the hospital electronic database will be used to screen the client 
population for initial eligibility based on age and ART initiation period, as noted in the Eligibility 
Criteria below. For this step, the hospital staff (and not the study coordinator) will mine the 
electronic database for this information to create a master list of eligible clients. Given the focus 
on treatment initiators, this process will be carried out weekly to identify newly diagnosed clients 
who are eligible to participate in the study.  
 
A daily list of expected clients will be generated from the master list for the study coordinators to 
locate those deemed eligible and who are due for a clinic visit. Once a client is located, a pre-
baseline visit will be initiated with the study coordinator approaching the client and inquiring 
about their interest in participating in an ongoing study. On confirming interest, clients will be 
taken to a separate study room to verify their eligibility, and to receive their consent to 
participate. Consented participants will be given a medication event management system 
(MEMS) cap and instructed to store one of their HIV medications in a pill bottle with the MEMS 
cap attached. Additionally, they will be given a study appointment after approximately one 
month of this initial visit for adherence data retrieval and baseline survey administration. The 
first month of adherence data will be used as a baseline and the intervention will not begin 
before this follow-up visit. 
 
Inclusion Criteria 
The study sample will consist of male and female clients aged 18 and older who have started 
ART at Mildmay within the preceding three months. Treatment initiation is an important eligibility 
criterion given the conceptual framework of the pilot, which suggests that habit formation during 
initiation is a key driver for sustained ART adherence over time. Based on electronic records 

7 
 
data from Mildmay, each month at least 100-150 clients with these characteristics begin 
treatment at the hospital (for a total of 1,758 in 2018); therefore, a large pool of potentially 
eligible clients will be available for recruitment. Given the nature of the intervention, inclusion will 
also require participants to own, or have access to a phone at least five days a week throughout 
the duration of the intervention, while being willing to receive text messages throughout the 
intervention period.   
 
Exclusion Criteria 
Children under the age of 18 were excluded for two reasons: 1) the pediatric clinic is separate 
from the main recruitment site (which primarily caters to adult clients), and 2) the intervention 
might require alteration to account for the specific needs of children and adolescents. 
Additionally, clients who are not mentally fit to understand the consenting or study procedures, 
as well as clients who speak neither English nor Luganda (the local language spoken by the 
majority of people in and around Kampala) were excluded. As both intervention groups rely on 
the receipt of text messages, clients who don’t own a cell phone or have access to one will also 
be excluded.  
 
Participation in another adherence study as well as non-ability or non-desire to use MEMS caps 
regularly throughout the course of the study will also be a basis for exclusion. Consequently, if 
the baseline MEMS reading suggests that participants opened their pill bottle less than 30% of 
days, and if that was not a consequence of low adherence, then the participant will be given a 
transport refund and will be unenrolled from the study. Finally, clients coming outside regular 
clinic working hours will be excluded.   
 
Randomization and Allocation  
Participants will be randomly assigned to either one of the treatment arms (T1 = Messages; T2 
= Incentives) or the control arm after consenting but will only be informed of their assignment 
after the baseline survey is over to minimize any potential influence of the assignment on the 
baseline survey responses. The distribution ratios for the randomization will be 1:1:1 and the 
assignment will be carried out through a computer-generated randomization component built 
into the baseline survey administration software, called Questionnaire Development System. 
The random assignment (to either the control group or one of the two intervention arms) will be 
revealed at the end of the baseline survey to both the participant and the study coordinator, who 
will therefore not know the respondent’s treatment assignment during the survey. Given the 

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nature of the intervention, neither the interviewers nor the participants can be blinded to the 
treatment status. However, the data analyst who will conduct the impact analysis will be blinded 
to treatment assignment. 
 
 
Procedures 
Interventions  
The pilot will include a control arm, along with two intervention arms – Messages (T1) and 
Incentives (T2).   
 
Control Group: Usual Care 
Participants assigned to this arm will receive care as usual, including the adherence support 
mechanisms that are part of usual care practices. At recruitment, participant will be educated 
about the importance of pill-taking using a leaflet that details information on how to establish 
healthy pill-taking routines. Participants will then be asked to select one of the following three 
pill-taking anchors: getting dressed in the morning, eating a meal (breakfast) in the morning, or 
eating dinner in the evening, which will also be described in a habit leaflet, and they will be 
asked to specify the time at which their anchor typically occurs. Once selected, participants will 
be asked to continue using their MEMS caps and to bring the caps during the next visit.  
 
During each of the subsequent study visits, scheduled roughly one month apart during the 
intervention period and 1-3 months apart subsequently, participants will be asked a short 
questionnaire inquiring about changes in their ART adherence behavior, including any changes 
in location, times, and social activities surrounding their pill-taking behavior and their ART 
adherence habit strength. They will also be asked about any clinical changes to their ART 
regimen, as well as about their daily MEMS cap usage. This is because pill-pocketing 
(dispensing of more than one dose in a given bottle opening event) is a common phenomenon 
among the population, with 15% of a previous study sample reporting pocketing [48]. If 
participants indicate pocketing, the study coordinator will work with the participant to find 
another solution to avoid pocketing and continue using their MEMS cap, and we will adjust for 
their pocketing in our assessment of their adherence outcomes. Finally, participants will be 
asked about any changes to their contact information or addresses, and updates will be noted in 
the contacts data. 
 

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The study coordinator will then download the readings from the MEMS cap, inquire about the 
participants’ next visit, and remind them to continue taking their pills on time. This procedure will 
be carried out throughout the intervention and post-intervention periods.  
 
Treatment Group 1: Messages Group 
Participants assigned to this arm will receive daily text messages in addition to care as usual 
during the three-month intervention period. When the participant is informed of their treatment 
assignment, they will be educated on the same habit leaflet as all other study groups and asked 
to pick an anchor and share the time of the day the anchor typically occurs. In addition, the 
study coordinator will register the participant’s cell phone number along with their language 
preference for text messages (English or Luganda) on an online text messaging system, Twilio. 
The system will include programmed text messages that will be sent to all participants at 2pm 
local time every day for the three-month intervention period. Table 1 shows some example text 
messages, each of which would be sent on a specific day of the week. Once registered, the 
study coordinator will send the participant a test message to confirm registration. If for any 
reason the participant is unable to confirm receipt of the test message (for example, if their 
primary number is owned by another person that they live with), the study coordinator will try 
registration again. If the registration is still not confirmed, the participant will be unenrolled from 
the study.   
 
Table 1: Example Text Messages for the Messages and Incentives Groups 
Hello, this is INMIND. Take your vitamins together with your existing routine for good health! 
Hello, this is INMIND. Forming routines requires effort now but will pay off in the end! 
Hello, this is INMIND. Don’t forget to take your vitamins every day at the same time! 
Hello, this is INMIND. Remember to stick with your healthy plans! 
 
During each subsequent intervention-period study visit for the enrolled participants, participants 
will be asked about the text messages in addition to the questions asked to the participants in 
the control group. Specifically, participants will be asked whether they have been receiving the 
text messages and whether they read them. MEMS data will also be downloaded during each of 
these subsequent clinic visits.  
 
Treatment Group 2: Incentives Group 
Participants assigned to this arm will receive monetary incentives in addition to daily text 
messages (as with the Messages arm) and care as usual, during the three-month intervention 

10 
 
period. Upon revealing their group assignment, participants will be registered on the Twilio 
platform following the same procedures as outlined for the Messages arm. Participants will also 
be informed that if at their next visit they have taken their medication on 70% or more of the last 
30 days within +/- one hour of their chosen anchor time, then they will be eligible to participate 
in a lottery to win mobile airtime. The study coordinator will note that they will receive three 
opportunities to participate in the lottery (i.e. at each study visit over the next three months, if 
they are eligible). To ensure participants understand the process, the study coordinator will 
carry out a mock prize drawing wherein participants will choose from one of three cards listing 
an airtime prize amount. The chosen card and corresponding prize will be revealed to the 
participant, and the amount listed on the card will be sent to the participant’s phone number (via 
Reloadly) in the form of a mobile top-up balance.  
 
During each subsequent study visit, the study coordinator will check the client’s MEMS cap data 
and fill out a form that asks questions about adherence behaviors (as with the control group), 
and text messages (as with the Messages group). The study coordinator will also ask about pill 
pocketing to assess prize eligibility. To avoid unfairly punishing participants who pocket doses 
(resulting in an under-reporting of MEMS data in the software), participants will be asked about 
an estimated number of doses pocketed and will be allowed to enter one wild card prize drawing 
when they did not reach the adherence threshold. They will be specifically informed that this will 
be a one-time exception. After the three-month intervention, participants will follow the same 
procedures as the Control and Messages groups.  
 
MEMS-cap procedures 
The MEMS caps will be used to assess the primary outcome measures – mean monthly 
adherence during intervention and post-intervention and a novel adherence measure assessing 
the timeliness of adherence during the intervention and post-intervention periods. The caps will 
be distributed to all participants regardless of their group assignment so as to avoid any 
spurious intervention effects associated with the cap use. The data captured by these caps will 
be downloaded at each clinic visit using a MEMS cap reader that will be connected to a study 
computer, and we will use these data to construct our participant-day-level measures of ART 
medication adherence.  
 
The study coordinator will assist the patient with dispensing their medication into a bottle we 
provide with an attached MEMS cap, or, if preferred by the patient, they can put the MEMS cap 

11 
 
on the medication bottle provided by the clinic. We will monitor adherence to only one daily dose 
of antiretroviral medication as studies show that rates of adherence do not differ significantly 
across medications taken by an individual patient [49]. All participants will be asked to use their 
MEMS cap continuously throughout the study and return with the cap and their pill bottle for 
each clinic visit. Participants will be informed that the cap records when the bottle is opened. 
They will also be informed that these data will not be shared with clinicians. 
 
 
Figure 2:  Schedule of enrolment, interventions, and assessments (SPIRIT Figure) 
 
Study Timeline  
Recruitment 
The recruitment (or pre-baseline) visit will be used as an opportunity to screen the clients. Once 
the client is found to meet the initial eligibility criteria, s/he will be given a MEMS cap, which will 
be used to track baseline adherence and study eligibility for approximately one month. In case 
their clinic visit does not coincide with the expected study visit, participants will be provided a 
study visit appointment and will be told that they will receive travel compensation for making the 
additional trip. Clients will also be consented to participate during this initial recruitment visit.   
 

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Months 1-3 Visits 
During the three-month intervention period, participants will be schedule for monthly clinic 
appointments and the study coordinators will a) collect information on changes or degradations 
of existing routine behaviors; b) conduct prize drawings with the Incentive group; and c) update 
contact information in case phone numbers or addresses have changed. After the first three 
months, this information will be collected during the participants’ regular clinic visits. When 
participants report the degradation of their selected behavioral anchor, a new daily routine will 
be identified for the anchoring strategy from the suggested list of three common routine 
behaviors. 
 
Post-Intervention Surveys 
Follow-up surveys will be administered at month three (i.e., at the end of the intervention) and 
month nine (i.e., six months after the end of the intervention) to evaluate behavioral persistence. 
These surveys will be designed to evaluate how the intervention affects both the primary 
outcomes and secondary outcomes, as well as cognitive and motivational factors that may be 
influenced by the intervention. Intervention effects over the nine-month study period will also be 
assessed as these effects might be most pronounced in the first months when the pill-taking 
routine is first established but then taper off as the novelty of the intervention fades or anchoring 
routines are changed. The post-intervention assessment will happen during a scheduled 
hospital visit to avoid participants having to make costly additional hospital visits specifically for 
interviews. 
 
Data Collection Methods 
Surveys 
The baseline survey contains questions pertaining to: 
1. Demographics and socioeconomic status, including age, gender, education, 
relationship status, employment type and status, income, preferred language, housing, 
economic shocks, food insecurity, and household composition 
2. Attitudes and beliefs about HIV medication, including adherence behaviors and 
perceived benefits, and community perceptions around pill-taking 
3. Sources of motivation for medication adherence, for example, reduction in HIV 
transmission, maintenance of good health and ability to look after family, and/or 
maintenance of good physical appearance 

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4. Habits associated with regular pill-taking, including pill-taking routines, missed doses 
and reasoning (to assess any perceptual and structural barriers to pill-taking), and costs 
associated with prescription fills. This would be assessed using the Self-Reported 
Behavioral Automaticity Index [50], which is a validated subset of the Self-Reported 
Habit Index [51] that measures the automaticity of performing a specific routine 
behavior based on responses to four questions (e.g., “taking my medication is 
something I do without thinking”) on a 7-point Likert scale from “strongly disagree” to 
“strongly agree.” 
5. Healthcare information, including perceptions on health since initiating ART initiation, 
and over the past month 
 
In addition, a measure developed by Falk et. al. will be used to assess risk and time 
preferences, altruism, trust, and positive and negative reciprocity, on a scale of 0-10, where 0 
means “completely unwilling to take risks” and 10 means “very willing to take risks” [52]. 
Additionally, the Intrinsic Motivation Inventory will be used to examine participants’ subjective 
motivation for taking medications [53]. The three-month and nine-month surveys will additionally 
include questions assessing comfort with using the MEMS caps, the acceptability of the text 
messages and prize drawings, and overall study satisfaction. Upon completing each survey, 
participants will be given 30,000 USh (~$8.25 USD) as travel compensation. 
 
MEMS Data and Access Forms 
The MEMS data will be automatically downloaded and stored electronically using the MEMS 
cap software that will be installed on a tablet accessible by the study coordinator. The other 
study data, including participants’ survey responses, monthly visit reports, and other information 
about study dropout, will be recorded by study personnel in Microsoft Access templates 
designed by the research team. These electronic data will be safely stored at Mildmay and 
securely transferred to the research team in the United States periodically during the study 
period, and at the end of the nine-month study.   
 
Chart Abstraction 
Participant’s viral load will be used as a complementary measure to the MEMS data for the 
assessment of ART adherence. They are now a part of routine clinical care at Mildmay with 
tests carried out when someone receives a positive HIV test result, after six and 12 months of 
the initial diagnosis, and every 12 months thereafter. Consequently, the results of the viral load 

14 
 
test will be chart abstracted and the data abstraction will be timed with the routine tests for the 
participants. 
 
Participant Tracking 
Extensive tracking information will be collected at recruitment and will be verified at each study 
visit. This will include mobile phone numbers, home address, and email addresses, as well as 
the contact information for two individuals who live in the same community and who the 
participant is comfortable and familiar with. These additional contacts are collected to ensure 
that the participant can be located in case their contact information changes. These procedures 
have limited attrition in the researchers’ previous studies to about 5% [44,48]. 
 
If a participant in either treatment group loses, breaks, or otherwise cannot use their mobile 
phone, then they will no longer be able to receive text messages as part of the intervention. To 
respond to this possibility, the study coordinator will record the functionality of participants’ 
mobile phones at each monthly visit and those with missing or broken mobile phones will be 
noted. Also, all active phone numbers of the participants (as it is not unusual for Ugandans to 
use more than one SIM card and/or phone) will be recorded to ensure an alternative means of 
delivering the messages exists, when available. Additionally, participants will be given a 
handout at the start of the study explaining that they should give the study team a call if they 
switch phones or phone numbers at any point during the first three months of the study, and that 
they will be rewarded with 3,000 USh for notifying the study coordinators of such a change. 
 
Outcomes  
The study will assess the following outcomes:  
Feasibility and Acceptability 
The feasibility and acceptability of the INMIND intervention will be assessed by the study 
retention rate and the attendance rate for scheduled clinic visits, as well as through survey 
responses collected at the end of the three-month intervention, and following the six-month 
post-intervention period. These survey measures ask participants about their ability to 
understand all intervention materials and their perceived value of the intervention. We will also 
conduct focus groups with a sample of study participants after the post-intervention survey to 
collect additional information on the study’s feasibility and acceptability.   
 
Preliminary Efficacy  

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Primary Outcome 1: Electronically measured mean medication adherence during intervention  
MEMS-data will be collected continuously over the course of the three-month intervention period 
allowing for mean adherence assessment during the intervention period. Specifically, the 
number of pill bottle openings detected by the MEMS cap will be used as a measure of each 
participant’s pills taken per day. Mean adherence will then be calculated as the number of pills 
taken per day during the intervention period, divided by the number of pills prescribed during the 
intervention for a given participant (i.e., # of actual bottle openings / # of prescribed bottle 
openings). This mean adherence measure will be capped at 100%, meaning that any pill bottle 
openings over the participants’ number of prescribed daily pills will be ignored. In this way, the 
mean adherence measure will range from 0 to 100 and will be calculated for each participant on 
each day of the intervention period. Only one of the daily ART medication doses will be used to 
calculate the primary mean adherence variable. Both the mean adherence over the three-month 
intervention and a monthly measure of mean adherence will be calculated and analyzed. 
 
Primary Outcome 2: Electronically measured mean medication adherence post-intervention  
Post-intervention, MEMS data will be collected continuously for six months to investigate post-
intervention mean ART adherence (‘persistence’). The calculation of this outcome is the same 
as that of Outcome 1 except for the timeline over which the data will be collected and analyzed. 
  
Primary Outcome 3: Routinization of ART adherence during intervention  
In addition to Outcomes 1 and 2, a novel measure of routine adherence will be assessed during 
the intervention period. The novelty of the measure is in that it is explicitly based on the 
temporal pattern of pill-taking. The measure will be calculated as the fraction of scheduled pills 
taken within a two-hour window (+/- one hour) around the typical time that participants report 
completing their existing routine behavior that anchors their pill-taking. This measure provides 
an objective way for determining the behavioral automaticity of pill-taking, and will be calculated 
as the mean of all prescribed pills taken around participants’ anchor time over the three-month 
intervention. 
 
Primary Outcome 4: Routinization of ART adherence post-intervention 
The fourth outcome will be calculated using the same procedures as Outcome 3. However, the 
data from which the measure will be assessed will be collected during the post-intervention 
period. 
 

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The team will also assess two secondary efficacy measures, as described below:  
Secondary Outcome 1: Retention in care  
Retention in care is an important metric of treatment adherence. Failure to remain in care is a 
commonly observed problem for treatment initiators. To assess how well participants will 
continue to remain in care, Mildmay electronic records will be used to evaluate the number of 
study participants who fail to observe their regularly scheduled clinic visits. Participants who 
don’t make any clinic visits for six months or more will be considered lost to follow up. The study 
coordinator will call them using the tracking information collected for the study to inquire about 
their reason for stopping care at the Mildmay clinic. This outcome will be measured as an 
indicator of whether the participants are still active clients at the clinic at the end of the nine-
month study.  
 
Secondary Outcome 2: Viral Suppression  
HIV RNA (viral load) is our final outcome measure. According to the AIDS Clinical Trials Group, 
virological failure is defined as a confirmed viral load > 200 copies/mL. Below this level, the viral 
load is considered undetectable. Importantly, this is a reliable biological measure of ART 
adherence, since strong adherence leads to lower viral load. Given the intervention design, viral 
load will be an important complementary measure of adherence. The analysis will examine the 
intervention effects on the likelihood of being virally suppressed at the end of the nine-month 
study period. 
  
Data Analysis 
Statistical Methods and Analyses 
Feasibility and acceptability will be analyzed using summary statistics derived directly from our 
self-reported measures. To estimate preliminary efficacy, statistical analyses comparing group-
level differences in the secondary and tertiary outcome measures will be performed. An 
Analysis of Covariance framework will be used to test for group differences in each secondary 
and tertiary outcome, controlling for the participant characteristics that are found to differentiate 
the groups at baseline. For analyses of dichotomous variables, such as viral suppression, a 
non-parametric McNemar’s test and an analogous multiple logistic regression will be used to 
control for covariates to assess group differences. In addition to static comparisons of group 
means for each outcome at three-month intervals, the longitudinal nature of the data will be 
leveraged by using repeated measures and time-series techniques. Specifically, a linear mixed 
model with repeated observations will be fit using maximum likelihood through ‘xtmixed’ in the 

17 
 
software package Stata to study group-level temporal dynamics in daily measures of the 
primary and secondary outcomes.  
 
Sample and Effect-size Estimation 
We will recruit a total of 150 participants and will assume a 90% retention rate through the 9-
month study period. This is a conservative estimate of attrition, as previous research in the 
same clinic and with a similar population observed only 6% attrition over 12-month study 
periods [44,48]. Given the study objectives of establishing acceptability, feasibility, and 
preliminary effectiveness, the targeted sample size may not have the power to detect many of 
the effects that would be clinically significant. Nonetheless, effect size calculations associated 
with 80% power (2-tailed test) with regard to the primary outcomes at month nine have been 
carried out. A recent study conducted at Mildmay suggested that mean ART adherence rates 
are ~ 75% (SD = 20) as measured by MEMS caps [44]. Using these parameters as estimates of 
adherence for the control group, and 10% attrition at month nine, a sample size of 150 will 
provide sufficient power to detect a 9% difference in mean adherence between the pooled 
intervention groups and the control group (effect size = .47), and a roughly 11% difference in 
mean adherence between the two intervention groups. This translates to the study being able to 
detect medium effect sizes.  
 
Qualitative Analysis 
Qualitative analysis will primarily be performed through semi-structured interviews and focus 
groups with clients, providers, and clinic administrators during the initiation and adaptation 
phases. The interviews administered during the initiation phase will primarily focus on 
perceptions of ART pill-taking as an activity of daily life and investigate the range of existing 
behaviors that could be used as cues (such as eating, daily prayers, or brushing teeth) to refine 
how INMIND could best support ART adherence routinization. During the adaptation phase, 
eight focus groups (four among participants in the Messages group and four among the 
participants in the Incentives group) will be organized to elicit additional qualitative information 
on areas of program improvements that may not be captured in the surveys.  
 
All qualitative data will be digitally recorded, translated into English, and uploaded into Dedoose, 
an analytic software package. Two qualitative researchers will independently read the text and 
identify all topics covered. A codebook that details the inclusion and exclusion criteria along with 
typical exemplars for each topic or theme will be developed. Inter-coder reliability (evidenced by 

18 
 
Cronbach’s alpha α ≥ 0.70) will be established until the coders converge on a single, agreed-
upon meaning for the thematic area. For each topic, they will identify the range of themes, with 
attention to those most commonly discussed (i.e., key themes) and least frequently discussed 
(i.e., outliers). They will produce research reports on specific topics describing the range, central 
tendency, and distribution of each theme.  
 
Data Management 
All data collected during the course of the study (outside of the consent forms, which will include 
the participants’ name and signature) will only have the existing clinic identifiers as the unique 
participant identifier. All other identifiable information will be stored separately. Data collection 
and storage hardware (i.e., tablets and computers) will be password protected and physical 
storage spaces will have a locking mechanism for security. All physical storage spaces will be 
located at the Mildmay RAND office in Kampala with access granted only to key personnel and 
the principal investigator (PI). These physical storage spaces will be used to store the consent 
forms and other physical tracking documentation. 
 
All data collection and on-ground study activities will be carried out by the study team in 
Uganda. This team will include a team leader, two lead interviewers, and three supporting team 
members. The design of the data collection instruments and protocols, the quality monitoring of 
the qualitative and quantitative data, and the data analysis will be carried out by the study team 
based in the United States (U.S.). Data collected on the ground will be transferred to the US 
team on a weekly basis through a secure web portal (Kiteworks).  
 
Published material will be free of any personally identifying information. There is no data 
monitoring committee since the trial was deemed minimal risk. The study team in the U.S. will 
still perform data monitoring and quality assurance exercises weekly during the nine-month 
study period. 
 
Handling Missing Data and Attrition 
Missing data for some variables will be imputed if a participant remained enrolled in the study. 
When participants drop out, multiple logistic regression models will be fit to assess whether this 
dropout is random. If it is not, “nonresponse” weights using logistic regression will be developed 
to correct for dropout. All analyses will reflect these design effects in the calculation of standard 
errors and statistical tests of significance. 

19 
 
 
Results 
This pilot study has been funded by the National Institutes of Mental Health in the United States 
(R34MH122331) and approved by the RAND Human’s Subjects Protection Committee (2020-
N0632), Mildmay Uganda Research Ethics Committee (0701-2021), as well as the Uganda 
National Council for Science and Technology (HS128ES). As of February 18, 2022, recruitment 
was completed. As of August 23, 2023, all the data collection activities were also marked 
completed; the analyses of the data are ongoing.  
 
Discussion 
Expected outcomes 
We hypothesize that our two intervention groups will display higher mean medication adherence 
and higher routinized medication adherence (i.e., pill-taking within +/- one hour of participants’ 
chosen anchor) during the three-month intervention relative to the control group. After more 
frequently using their anchoring strategy, we then hypothesize that our two intervention groups 
will better maintain their mean medication adherence and routinized medication adherence over 
the six months after the intervention is withdrawn. Finally, we hypothesize that our second 
treatment group that receives both text message reminders and small incentives for using their 
anchor during the three-month intervention will more strongly maintain their mean medication 
adherence and routinized medication adherence during the six-month post-intervention period.  
 
Comparison to prior work  
INMIND has a strong scientific premise that addresses a critical knowledge gap in the literature 
around the design of interventions for establishing and maintaining long-term behavior change. 
A growing literature in the field of psychology targets long-term behavior change [18,43]; 
however, most of the intervention methods are one-off interventions that do not support 
participants during the approximately three-month routinization process [17,20,54,55]. 
Behavioral economics-based interventions have also had limited efficacy in maintaining long-
term behavior change. For example, incentives have successfully changed a range of health 
behaviors by countering present bias [38–41], including improved ART adherence [42],  but 
these interventions typically show only short-term impact that dissipates after the incentives are 
withdrawn [38,43]. In our own prior studies, we also found that incentives did not have persistent 
effects, and only participants who showed timely adherence (an indicator that they potentially 

20 
 
anchored pill-taking to an existing routine) maintained high adherence after the incentives were 
withdrawn [44].  
 
Our combined intervention approach attempts to leverage the successful components of these 
existing psychology and behavioral economics-based interventions to better maintain ART 
adherence. If successful, this intervention will help to expand the understanding of the habit 
formation process and the common psychological barriers to successfully stick to new health 
behaviors. The study also addresses biological variables such as age and sex appropriately and 
incorporates them in both the impact analysis and when testing for age and sex differences in 
behavioral biases and intrinsic motivation. Such analyses will be especially useful in designing a 
large-scale intervention that can assist all treatment initiators with establishing and maintaining 
long-term ART adherence.  
 
Limitations 
The study is not without limitations.  First, the study will sample from one clinic in Uganda, 
limiting the generalizability of our results. Second, the small sample size limits the team’s ability 
to detect clinically meaningful effect sizes. While this is not the intended aim of this feasibility 
and acceptability study, the small sample size is still a limitation to the statistical analyses. Third, 
ART adherence will only be measured over nine months, so future research will be needed to 
assess ART adherence over longer durations. Fourth, ART adherence will be measured using 
MEMS caps, which is currently one of the most accurate ways to measure medication 
adherence, but conscious manipulation of the pill bottle openings by the participants is still a 
possibility that may lead to an overestimation of the study’s adherence outcomes for participants 
in the Incentives group who may use deception to increase their chances of a prize drawing.  
 
Dissemination and Future Directions 
The team will use peer-reviewed publications and conference presentations as the primary 
means of results dissemination. The findings will be relevant to those interested in the 
behavioral mechanisms that underly successful long-term ART adherence, and more broadly, 
the mechanisms underlying long-term behavior change. Additionally, the findings will be utilized 
in the design of a larger-scale randomized controlled trial that we will use to rigorously assess 
the effectiveness of the INMIND intervention for establishing long-term ART adherence habits. 
In addition to future randomized controlled trials, we plan to use the detailed MEMS data on the 

21 
 
timing of daily pill-taking to inform statistical models of the habit formation process, which will 
guide new intervention designs for promoting ART adherence habits.  
 
 

22 
 
Data Availability 
De-identified research data will be made available, along with the survey instruments, to 
interested external researchers through collaborative agreements with the PI and co-
investigators, as required by the National Institutes of Health’s data sharing policies. 
Trial status  
The trial was retrospectively registered on Clinicaltrials.gov (registration number: 
NCT05131165) on 12 November 2021. The study start date was 25 October 2021, and the 
protocol was last updated on 22 September 2022. The primary completion date was 23 August 
2023, and the study completion date is expected to be in August 2025. 
List of abbreviations 
AIDS: acquired immunodeficiency syndrome 
ART: antiretroviral therapy 
HIV: human immunodeficiency virus MEMS: medication event monitoring system 
SPIRIT: standard protocol items: recommendations for interventional trials 
 
 
 
 

23 
 
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