Study design
This was a randomized, controlled clinical trial (IRCT2015111712211N2) with two parallel arms designed to demonstrate the effect of BPMAP (Supplementary file1) on self-management of hypertensive patients in adherence to the treatment and control of hypertension risk factors (12). Writing this article is guided by the CONSORT 2010 checklist (See additional file 1).
Study setting
Tehran Heart Center is a third-level cardiovascular subspecialty medical center affiliated to Tehran University of Medical Sciences. The center admits about 113,000 outpatients, 24,000 hospitalized patients, and performs 4,000 open heart surgeries each year (13).
Participants
The participants included patients with primary hypertension diagnosed and confirmed by their physician. Inclusion criteria were the 30-60-year age range, literacy, treatment of hypertension during the past year, possession of and ability to use a smartphone, willingness to participate in the study, and residence in the study region throughout the study. Exclusion criteria were hypertension complications such as myocardial infarction, stroke, other cardiovascular diseases, diabetes, and physical disability.
Interventions
Participants in the intervention group received a mobile application-based educational-supportive intervention, along with the routine treatment. The content and features of the application were prepared based on the educational needs of hypertensive patients (14). The application had the following features; a) recording blood pressure and receiving feedback of the recorded blood pressure, b) saving the recorded blood pressure levels and plotting them as a chart, c) reminding the time of drug consumption, visit date, and blood pressure measurement, d) healthy diet(DASH and low-salt diet) and weight loss plans, e) knowledge-based information on the nature, control, and treatment of the disease, f) motivational and supportive programs for smoking cessation g) sending notifications or informing one of the patient’s family members of critical blood pressure levels, h) sending general motivational messages and reminders about adherence to treatment to all patients and specific individual messages based on patient characteristics, and i) saving the recorded information by users on the portal for physicians and researchers.
Participants in the comparison arm received the usual treatment including clinical examinations, such as measurement of blood pressure and weight, patient history, laboratory tests and paraclinical services tailored to individuals’ conditions, drug treatment according to the JNC8, recommendations and answers to patient questions.
Outcomes (Primary and secondary)
Adherence to antihypertensive medication was considered as the primary outcome, assessed with the 14-item Hill-Bone Scale (15). The secondary outcomes included clinical and behavioral outcomes, such as adherence to DASH diet, reduced sodium and fat intake, regular blood pressure monitoring, physical activity, predisposing, enabling, and reinforcing factors in adherence to treatment.
Adherence to DASH diet and sodium reduction: The intake of salt, fat, low-fat dairy products, fruits, and vegetables over the past week was evaluated.
Regular blood pressure monitoring: The frequency of blood pressure in the application was recorded in the study period.
Physical Activity: The degree of change in the frequency and time allocated to physical activity was evaluated in two categories of moderate and severe physical activity.
Predisposing, enabling, and reinforcing factors in adherence to treatment: The effect of these factors was evaluated based on the questionnaire items.
Sample size
Group sample size of 60 and 60 (120 people in both group) achieve 80 power to detect at least 5 score (SD= 10) difference on the Hill-Bone Compliance to high blood pressure (15) using two sided T test at the significance level of 5%.
Randomization
Patients were referred to the physician to assess the inclusion and exclusion criteria after obtaining informed consent. The baseline survey was then completed, and the participants were randomly divided into two groups. Randomization was performed using a randomized website with block sizes of four. The allocation ratio was 1:1for each arm. Patients from each group were visited at two different schedules.
Implementation
Individuals were given one week to review and consult with the family to read and sign the informed consent form. After approval by the assessor physician, the initial assessment questionnaire was completed by a trained interviewer (Fig. 1). The application was installed on the mobile phones of the intervention group and described to individual patients. Patients’ sphygmomanometers were calibrated at the application installation time to ensure correct measurement of blood pressure at home.
Follow-up assessments
Participants in both groups had an initial visit and six follow-up visits. The first 5 visits were performed with a two-week interval and the last one 24weeks after the first visit (Table 1). In both groups, clinical evaluation and the questionnaire completion were done at baseline, eight weeks after receiving the application, and at the 24thweek.
Data collection methods
The primary outcome was measured by the Hill-Bone Scale and secondary outcomes by a mercury sphygmomanometer and the researcher-made questionnaire.
The questionnaire contained patients’ demographic information, treatment status, some health-related behaviours as the initial assessment. A number of the PRECEDE model constructs (predisposing, enabling, and reinforcing factors), the World Health Organization STEPS questionnaire for monitoring chronic risk factors, (16), the Hill-Bone Compliance Scale, and the Global Physical Activity Questionnaire (GPAQ) guide were used in its design (17). The questionnaire validity and reliability were evaluated and confirmed.
Data management
Patients’ information was obtained from the self-report questionnaire and the application. When connected to the Internet, all user clicks in the application were stored on the portal (Supplementary file 2, table 1). The final databank was prepared in SPSS. A double entry was made to ensure that the data was entered correctly. In the event of any discrepancy, the information entered was verified with the initial data.
Statistical methods
Quantitative variables were reported as mean (standard deviation) and qualitative variables as frequency (frequency percentage). To evaluate the effectiveness and observe the changes over the predicted time, the produced content was used in the form of a piece of software including adherence of hypertensive patients to the pharmacological therapy, adherence to the DASH diet, adherence to regular blood pressure monitoring, knowledge enhancement, attitude improvement, and self-efficacy of the Repeated Measurement ANOVA (GLM) test. Changes in the baseline data were entered as the covariate, and the second and third measurements as the repeated variable. The intervention group was selected as the comparison variable.