Table 1.

User interface design dimensions from International Organization for Standardization (ISO) standard 9241-12 and corresponding WoundCheck design features.

Information display dimension	Definition	Method employed	Sample app design features
Clarity	Content conveyed quickly and accurately	Physician review; focus group	All app language validated by physician review panel (for clinical usefulness) and lay focus group (for interpretation)
Discriminability	Information is readily distinguished	Iterative redesign	Tap-only response options (no text entry or scrolls) Consistent 3D button placement below text Redesign of image capture screen to prevent errors and reduce wrong-button taps   Color-coded buttons
Conciseness	No extraneous content	Focus group review of content	Yes or no questions for symptoms Draft language reviewed by focus group to reduce word count while retaining interpretation
Consistency	Information is presented in the same way consistent with expectations	Focus group review of layout; Iterative redesign	All response screens are identical Each module contains review screen prior to submission
Detectability	Attention is directed to salient information	Multidisciplinary design team; physician review	Image review screens to ensure quality image Feedback screens to track and confirm submission Buttons are 100x100 pixels (0.33 in) or larger Font fills the frame
Legibility	Easy to read content	Focus group test; iterative redesign	Readable Helvetica Neue bold font choice, size 26 or larger with high contrast display (black type on white background) Button shadowing
Comprehensibility	Meaning is unambiguous and clear	Focus group review of content; physician review	6th grade reading level Focus group read-back of app questions “in your own words” to ensure faithful interpretation Focus group feedback for image capture training