Think-Aloud Testing of a Companion App for Colonoscopy Examinations: Usability Study

Colonoscopies are vital for initial screening, follow-ups, surveillance of neoplasia, and assessing symptoms such as rectal bleeding. Successful colonoscopies require thorough colon preparation, but up to 25% fail due to poor preparation. This can lead to longer procedures, repeat colonoscopies, inconvenience, poorer health outcomes, and higher costs. eHealth tools can enhance bowel preparation and potentially reduce the need for repeat procedures.

This usability study aimed to identify strengths and weaknesses in a prototype companion app for colonoscopy examinations. The objective was to obtain in-depth insights into the app's usability, ease of use, and content comprehension, with the aim of refining the tool to effectively fulfill its intended purpose, guided by feedback from potential users.

From February to August 2024, we conducted a qualitative study using the think-aloud procedure. Each session involved 6 tasks and a semistructured interview to delve deeper into participants' task experiences. All think-aloud sessions and interviews were recorded. Quantitative usability questions were analyzed using Microsoft Excel, while qualitative data underwent coding and analysis based on thematic analysis principles.

In total, 17 individuals, all smartphone users, participated in this study. Participants were recruited from 1 hospital, 1 private clinic, and 1 patient organization in Switzerland. The study found that participants rated the app's usability metrics positively, with an overall mean rating of ease of use at 4.29 (SD 0.59), usefulness at 4.53 (SD 0.72), and comprehensibility at 4.29 (SD 0.92). For the individual features, the mean ratings for ease of use were between 4 and 4.65, usefulness ranged from 4.35 to 4.82, and comprehensibility received ratings between 4.29 and 4.53, all measured on a 5-point scale, where 1 represented low agreement and 5 indicated high agreement. Additionally, 100% of participants indicated they will or may use the app if they require a colonoscopy examination. Participants highlighted the need for reminders and alerts in the week leading up to the colonoscopy, along with tailored content, simplified language, and visual aids.

The app prototype demonstrated favorable results with the majority of participants, and the testing process enabled the prompt identification and resolution of usability issues. The next phase will prioritize and assess potential improvements based on urgency and feasibility to guide a focused development plan. Usability testing highlighted features such as push notifications and personalized content as top priorities for participants, making them key areas for immediate attention. Moving forward, the app has the potential to function effectively as a companion app for colonoscopy examinations. To achieve this, further studies with a larger sample in real-world settings will be crucial.