Evaluation and redesign of longitudinal Patient-Reported Outcome score visualizations for improved trend interpretability: a randomized experimental study

Objectives:Design and test an alternative visualization of Patient-Reported Outcomes Measurement Information System (PROMIS) scores to improve visualization efficacy by addressing common confusion surrounding the direction of improvement when reading line charts of PROMIS symptom scores over time. Materials and Methods:We designed a "smiley"-timeline visualization that encodes scores via color and pictographs instead of y-axis direction.We compared trend interpretation when using smiley-timelines vs. line charts via a preregistered, online, randomized, between-subjects experiment with pair-wise comparisons of charts.Participants were recruited via Prolific.com,fluent in English, over age 45, and able to interpret stimuli correctly without initial instruction, allowing for analysis of differences in response times without explicit instruction or learning time confounding results.