Men's interpretations of graphical information in a videotape decision aid

To examine men's interpretations of graphical information types viewed in a high-quality, previously tested videotape decision aid (DA). SETTING, PARTICIPANTS, DESIGN: A community-dwelling sample of men >50 years of age (N = 188) balanced by education (college/non-college) and race (Black/White) were interviewed just following their viewing of a videotape DA. A descriptive study design was used to examine men's interpretations of a representative sample of the types of graphs that were shown in the benign prostatic hyperplasia videotape DA.

Men provided their interpretation of graphs information presented in three formats that varied in complexity: pictograph, line and horizontal bar graph. Audiotape transcripts of men's responses were coded for meaning and content-related interpretation statements.

Men provided both meaning and content-focused interpretations of the graphs. Accuracy of interpretation was lower than hypothesized on the basis of literature review (85.4% for pictograph, 65.7% for line graph, 47.8% for horizontal bar graph). Accuracy for pictograph and line graphs was associated with education level, chi2(1) = 3.94, P = 0.047, and chi2(1) = 7.55, P = 0.006, respectively. Accuracy was uncorrelated with men's reported liking of the graphs, chi2(1) = 2.00, P = 0.441.

While men generally liked the DA, accuracy of graphs interpretation was associated with format complexity and education level. Graphs are often recommended to improve comprehension of information in DAs. However, additional evaluation is needed in experimental and naturalistic observational settings to develop best practice standards for data representation.