Peer Support Intervention Effect on Medication Adherence, Self-care and Knowledge Among Patients With Diabetes: A Randomized Control Trial
Phase: NA
Conditions: Peer Influence, Medication Adherence, Self Care
Sponsor: Addis Ababa University

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Study Protocol and SAP 
 
 
 
 
 
 
Official Title: Effect of Peer Support Intervention on Medication Adherence, Self-care 
and Knowledge Among Patients with Diabetes     
 
  
 
 
ClinicalTrials.gov ID (NCT number): NCT07145983 
 
 
 
Protocol Date: January 1/ 2025 
 
 
 
 

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Scientific Background 
Diabetes mellitus is a chronic condition that requires consistent adherence to treatment, regular 
self-care, and adequate knowledge of the disease to prevent complications and improve quality of 
life. However, many patients struggle to maintain optimal adherence and integrate self-care into 
their daily routines. Now a days, many diabetes self-management modalities have emerged as a 
promising approach to address these gaps. This randomized controlled study evaluated the effect 
of a structured peer support program on medication adherence, self-care practices, and diabetes-
related knowledge among patients with diabetes who attended follow-up at a tertiary hospital. 
 
Study Objectives 
➢ To assess the effect of a peer support group intervention on Medication adherence 
among patients with diabetes on follow up at ACSH 
➢ To assess the effect of peer support group intervention on self-care practice among 
patients with diabetes on follow up at ACSH  
➢ To explore the effect of peer support group interventions on patients' knowledge among 
patients with diabetes on follow up at ACSH 
Study Design & Methods 
Study Setting 
The study was conducted at Ayder Comprehensive Specialized Hospital (ACSH), the largest 
referral hospital in the Tigray region, situated in Mekelle city, about 780 kilometers north of Addis 
Ababa, Ethiopia's capital. ACSH serves an estimated 10 million people from Tigray and 
neighboring regions, including Amhara and Afar. With a capacity of 500 beds, the hospital 
manages approximately 10,000 inpatient admissions and 100,000 outpatient visits annually. 
The diabetic clinic at ACSH is a major center for diabetes management, providing follow-up care 
for around 5,000 patients. Outpatient services are delivered two days a week, serving more than 
100 patients per visit. The clinic is operated by two senior physicians, residents and five nurses 
who provide a range of essential services, such as diabetes education, individualized counseling 
on diet, emergency care, medication adherence and insulin administration. Antidiabetic treatments 
are adjusted based on fasting blood glucose and HbA1C results. Newly diagnosed patients receive 
intensive follow-up during the first six months to help maintain optimal blood glucose levels. 

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Study Design and Period 
A randomized controlled trial (RCT) design was employed from January to September 2025 to 
evaluate the effect of a peer support intervention among patients with diabetes attending ACSH. 
This trial has been registered and can be accessed at: https://clinicaltrials.gov/study/NCT07145983 
which initially released on August 21, 2025. 
Sample Size Determination   
The sample size for this study was determined separately for the peer support group and the two 
comparison groups. Five participants were purposively selected for the peer support group based 
on predefined eligibility criteria. Selection was done in collaboration with clinical service 
providers at the diabetic center to ensure the inclusion of experienced individuals, following 
guidance from validated studies on peer support interventions for diabetic patients(28). For the 
intervention and control groups, the sample size was calculated using the statistical superiority 
design formula for continuous variables: n = [(Z₁ + Z₂)² × (2S²)] / d². In this formula, Z₁ represents 
the z-score for a 95% confidence level (1.96), Z₂ corresponds to a power of 80% (0.84) (29). The 
standard deviation (S = 4) was estimated based on the range of scores from the Morisky Medication 
Adherence Scale with eight items (MMAS-8), which ranges from 0 (indicating poor adherence) to 
8 (indicating high adherence). A minimum clinically meaningful difference of 2 points (d = 2) in 
adherence scores between the groups was considered for sample size calculation. This calculation 
provided the required sample size for the intervention and control groups to detect a meaningful 
difference in adherence outcomes (30).  A total of 100 eligible patients with diabetes were recruited 
using a simple random sampling method with 50 participants assigned to the intervention group 
and 50 to the control group.  
Standard Care 
Scheduled consultations with a physician, laboratory investigations and medication refill were the 
standard care services delivered for patients with diabetes during the clinic’s service days at the 
diabetic center of the hospital. Follow-up appointments are typically scheduled every two to three 
months. Newly diagnosed patients receive individualized counseling from the nurse on duty, 
addressing diabetes-related and patient-specific concerns. Additionally, patients collect their 
prescribed medications from the hospital pharmacy up on visiting the hospital for follow up in 

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which standard pharmacy care was also served. Thus, in this trial both groups received this 
standard health care service equally.  
Peer Support Intervention and Procedures  
The study was conducted in two phases. Phase I involved the recruitment and preparation of the 
peer support group (n = 5). These individuals were selected in advance and remained consistent 
throughout the intervention period. One registered nurse was recruited to serve as a facilitator for 
the peer support sessions. The recruited peer educator attended an initial 2-days training program 
on how to facilitate and structure the consecutive sessions which included role-playing exercises 
to prepare them for effective communication and engagement with intervention group members. 
They were primarily trained in their local language (Tigrigna) to educate and share their experience 
to peers on scheduled sessions focused on treatment adherence, self-care behaviors, and diabetes-
related knowledges which was adopted from the Internation Diabetes Federation peer leader 
manual. 
On Phase II, enrollment of the intervention and control group was continued during their regular 
appointments at the diabetic clinic. Both groups were matched in terms of sociodemographic 
characteristics and disease-related factors. While the control group received baseline assessments 
only and continued with standard care, members of the intervention group attended a one-hour 
orientation session to explain the study's objectives, potential risks of withdrawal, and the 
importance of sustained participation. Following this, each peer supporter was assigned to a group 
of 10 intervention participants and formed five peer-led support groups. 
The peer support intervention was delivered through scheduled, one-hour group session during 
regular clinic appointments. These interventions were conducted in the 2nd, 4th and 6th months, i.e., 
for three rounds over the study period for each group. Each group member was expected to 
participate in all the three sessions, which were structured around three core components: (a) 
sharing personal experiences and knowledge about diabetes and its complications, blood glucose 
triggering factors and providing psychosocial support focused on the self-management (disease-
related component); (b) offering education and encouragement for medication adherence 
(medication adherence component); and (c) supporting the integration of dietary and physical 
activity recommendations into daily routines (behavioral component). The principal investigator 
conducted close follow-up of the intervention sessions to document the topics covered during each 
session and address any challenges encountered during the implementation. Monthly debriefing 

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sessions were conducted to discuss their experiences and challenges. Feedback on their 
performance was provided based on each group sessions. 
Data collection Instruments and Measurements  
Data were collected using participant interviews, review of medical records as well as adapted 
diabetes questionnaires for each outcome variable in the intervention and control groups. Four 
clinical pharmacists who were blinded as to the group assignments were recruited to collect the 
consecutive data. Medication adherence of each group was assessed through a mixed method using 
the Morisky Medication Adherence Scale (MMAS-8) and self-reported pill count. The MMAS-8 
consisted of seven dichotomous items and one item rated on a five-point Likert scale. To minimize 
acquiescence bias (‘yes-saying’), each ‘no’ response was assigned one point, except for item 5, 
which was reverse-coded. The eighth item provided five response options, scored from 0 to 1 in 
0.25-point increments. Based on the total score, patients were classified as low adherers (score 
<6), medium adherers (score 6 to <8), or high adherers (score = 8).  
Self-care practices were measured using the Summary of Diabetes Self-Care Activities (SDSCA) 
scale, which captures five key domains of diabetes management. General diet was measured as the 
mean of two items, while specific diet included two items, one of which was reverse-coded, 
Exercise, blood-glucose testing, and foot-care were each evaluated by averaging two respective 
items. 
Diabetes-related knowledge was assessed using a structured questionnaire adapted from the 
Diabetes Knowledge Test (DKT) (34). The instrument included 14 core items administered to all 
participants, with an additional 9 items for insulin users, The DKT presents six dimensions, 
including: (i) food, with four items about the composition of food, its safety and which types of 
food should be avoid; (ii) ways to assess diabetes, with two items regarding methods to assess this 
disease; (iii) effect of external variables on diabetes control, with six items such as physical 
exercise or infection, on diabetes control; (35) signs and symptoms, containing three items 
concerning the symptoms associated with natural evolution of diabetes and failures on its 
monitoring; (v) control over medication and its effects, with six items measuring individual’s 
response to adversities or forgetting to take insulin; and (vi) causes of glycemic deregulation, with 
two items aimed at understanding the individual’s perception of possible causes that may change 

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blood glucose levels. Each correct response was scored as 1, and incorrect or “don’t know” 
responses were scored as 0. Non-insulin users were scored out of 14 points, while insulin users 
were scored out of 23 points. Participants were classified as having good knowledge if their score 
exceeded the mean, and poor knowledge if their score was at or below the mean. All baseline pre-
intervention data including surveys and clinical outcomes were collected in the first week, and 
follow-up data was collected in the 1st month of post-intervention. 
Eligibility Criteria  
 
Study Population and Eligibilities  
The study involved diabetic patients aged 18 to 65 years who were receiving follow-up care at 
ACSH. Participants were divided into three groups whose were categorized as the peer support 
group, the intervention group and the control group.  Eligible participants of the peer support group 
had a minimum of 10th grade educational background with more than three years of disease 
duration, stable glycemic control with HbA1C <7.5%), a documented history of regular follow-up 
at ACSH. Besides, the intervention group were those who received the peer-led educational 
sessions, which aimed to improve adherence to diabetes treatment, enhance self-care behaviors, 
and increase diabetes-related knowledge. Eligible participants of this group were those who had 
on at least one diabetes medication, most recent HbA1C value of ≥7.5% based on information 
collected by the research team at point of care HbA1C testing and those had regular follow-up 
visits at ACSH. The control group comprised patients with diabetes meeting similar eligibility 
criteria as the intervention group but received standard diabetes care during routine clinic visits 
without additional peer support.  
Patients with diabetes who declined to participate in any of the groups, those diagnosed with other 
concurrent endocrine disorders (such as thyroid disease, obesity, or gestational diabetes) and 
chronic diseases like cardiac heart failure, hepatitis and cancer were excluded. Additionally, those 
enrolled in other educational programs during the study period and health professionals were 
excluded from this study. 
 
Statistical Considerations 
Data were entered into Epi-Data version 4.6 and exported to SPSS version 25 for analysis. 
Descriptive statistics such as frequencies, percentages, means, and standard deviations were used 

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to summarize sociodemographic, clinical, and behavioral characteristics of participants. 
Medication adherence, diabetes knowledge, and self-care practice scores were calculated 
according to their respective validated scales. The effect of the peer support group intervention 
within-group and between-group was assessed and comparisons were performed. Paired t-tests 
were used to determine changes in the outcome variables within each group (intervention and 
control) before and after the intervention. Independent sample t-tests were applied to compare 
mean differences between groups. Furthermore, a Difference-in-Differences (DiD) approach was 
employed to evaluate the net effect of the intervention by comparing the changes in outcomes from 
baseline to follow-up between the intervention and control groups.