Objective This research investigated whether safety labeling design guidelines, such as the American National Standards Institute (ANSI) Z535 series, contribute to better warnings. Background Studies investigating the impact of safety label formatting on warning effectiveness have produced mixed findings. Additionally, research has failed to find a consistent relationship between measures of predicted and actual compliance. One commonality is that all of these studies have investigated the ANSI Z535 guidelines as a binary variable rather than as an integrative system of separable features. Method We measured predicted compliance using both a within-subjects and a between-subjects design, but actual compliance using only a between-subjects design. Data were analyzed using both analysis of variance and linear/probit regressions to test the relationships between warning features recommended in the ANSI Z535 guidelines and measures of behavioral compliance. Results Predicted compliance assessed via a within-subjects design differed greatly from predicted compliance assessed via a between-subjects design. Levels of predicted and actual compliance were most similar when both measures were assessed using a between-subjects design. Consistent with previous research, location had a strong relationship with actual compliance, but surprisingly, presence of an ANSI-style orange warning header had a negative relationship with compliance. Conclusion The choice of experimental design and analytical methods can dramatically influence a study’s results and conclusions drawn. This research identified several aspects of experimental design that should be considered in future research on warning effectiveness. Application Testing features recommended in the ANSI Z535 guidelines under varying conditions can contribute to the development of more effective warnings.

Debate continues regarding the relative effectiveness of the ANSI Z535 guidelines for the design and placement of warnings. Research shows consistent positive effects of these guidelines on precursors to warning compliance (e.g., noticing, reading, intended compliance), but less consistency on compliance behavior. Challenges in interpreting these findings stem from factors such as small sample sizes, varying research designs and experimental conditions, and treating the ANSI Z535 guidelines as a singular entity rather than as an integrative system of separable features. Here, we address these issues by testing perceptions of warning label effectiveness using a large sample ( n=533) and systematically manipulating variables cited in the Z535 guidelines. Collectively, we tested eight label designs for a (2-drawer and 4-drawer) file cabinet and found statistically significant relationships between design recommendations from the ANSI Z535 guidelines and perceptions of effectiveness. The presence of a warning header and pictogram exerted the largest effects. Bulleted text and (larger) font size were also related to increased perceptions of effectiveness.