Human Performance Evaluation of Graphic and Textual CRT Displays of Diagnostic Data

A study was conducted to determine the effectiveness of four alternative CRT display formats for diagnostic data. The formats were narrative text, structured text, black and white graphics, and color graphics. The evaluation measured subjects' speed and accuracy of response to a question requiring interpretation of a display. The results indicated that accuracy of response did not vary with format. Speed of response, however, did vary with format. Responses to both graphic formats were consistently faster than to the narrative text format. With additional practice, responses to the structured text format were just as fast as to the graphic formats.