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Background: Childhood obesity is a serious public health issue among minority youth in the United States. Technology-enhanced approaches can be effective for promoting healthy behavior change.

Objective: The purpose of this study was to test the usability of prototypes of a Web-based interactive tool promoting healthy dietary behaviors to reduce childhood obesity risk in urban minority youth. The Web-based tool comprised a manga-style comic with interactive features (eg, sound effects, clickable pop-ups), tailored messaging, and goal setting, and was optimized for use on tablet devices.

Methods: Latino and black/African American children ages 9 to 13 years were recruited to participate in two rounds of usability testing. A modified think-aloud method was utilized. Self-reported surveys and field notes were collected. Audio recordings and field notes from usability testing sessions were systematically reviewed by extracting and coding user feedback as either positive comments or usability or negative issues. The quantitative data from self-reported questionnaires were analyzed using descriptive statistics.

Results: Twelve children (four female; eight black/African American) with a mean age of 10.92 (SD 1.16) years participated. Testing highlighted overall positive experiences with the Web-based interactive tool, especially related to storyline, sound effects, and color schemes. Specific usability issues were classified into six themes: appearance, content, special effects, storyline, terminology, and navigation. Changes to the Web-based tool after round 1 included adding a navigation guide, making clickable icons more visible, improving graphic designs, and fixing programming errors. In round 2 of testing (after modifications to the Web-based tool were incorporated), many of the usability issues that were identified in round 1 did not emerge.

Conclusions: Results of testing will inform further development and finalization of the tool, which will be tested using a two-group pilot randomized study, with the goal of reducing childhood obesity risk in minority, low-income youth.


This article was originally published in JMIR Formative Research, available at DOI:10.2196/formative.9747.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (



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