Formative Evaluation of a Smartphone App for Monitoring Daily Meal Distribution and Food Selection in Adolescents: Acceptability and Usability Study (Preprint)

Billy Langlet, Christos Maramis, Christos Diou, Nikolaos Maglaveras, Petter Fagerberg, Rachel Heimeier, Irini Lekka, Anastasios Delopoulos, Ioannis Ioakimidis

Abstract: Background: Obesity interventions face the problem of weight regain after treatment, as a result of low compliance. Mobile health (mHealth) technology could potentially increase compliance and aid both healthcare providers and patients. Objective: To evaluate a mHealth system used to monitor dietary habits of adolescents in real-life, as a first step in the development of a self-monitoring and lifestyle management system against adolescent obesity. Methods: Twenty-six high-school students were recruited from a school in Stockholm, Sweden. For two to three weeks, participants used a custom Smartphone application, integrating measurements from two external sensors for objective collection of dietary habits. The application and sensors were used by the participants, without supervision, to record as many main meals and snacks as possible in real-life. Feasibility was assessed following the ‘mHealth evidence reporting and assessment checklist’ and usability was assessed by questionnaires. Compliance was estimated based on system use, where an individual registration frequency of three main meals (breakfast, lunch and dinner), per day, for the period of the experiment constituted 100% compliance. Results: Participants included in the analysis had a mean (±SD) age of 16.8yr (±0.7) and a BMI of 21.9kg/m2 (±4.1). Six participants required additional information on system use. No adjustments were made to the study protocol during the study. The system received a ‘Good’ grade (77.1 out of 100) on the System Usability Scale, with most participants reporting that they were comfortable using the Smartphone application. Participants were most willing to use the application at home, but also at school. Most student suggestions for improvements concerned design choices for the application. Of all main meals, the registration frequency increased from 70% the first week, to 76% the second week. Participants reported that 40% of the registered meals were home-prepared, while 34% of the reported drinks contained sugar. On average, breakfasts took place at 08:30 (from 05:00 to 14:00), lunches took place 12:15 (from 10:15 to 18:15) and dinners took place 19:30 (from 15:00 to 23:45). When comparing meal occurrence during weekdays vs weekends, breakfasts and lunches were eaten three hours later during weekends, while dinner timing was unaffected. Conclusions: From an infrastructural and functional perspective system use was feasible in the current context. Acceptability and usability of the Smartphone application was high in the intended end-user group. The system appears promising as a low-effort method to provide a high number of dietary habit measurements.

External IDs:doi:10.2196/preprints.14778