Abstract
OBJECTIVE: Limited health literacy negatively impacts understanding of medication-related information. We describe an innovative methodology designed to optimize user understanding of patient medication labeling through the systematic application of evidence-based health literacy principles, using the Patient Package Insert (PPI) for bezlotoxumab (ZINPLAVA™, Merck & Co., Inc., Kenilworth, NJ, USA) as an example. METHODS: We used a mixed-model, iterative approach consisting of three phases: (1) content development; (2) focus group testing; and (3) comprehension testing. Content development was based on evidence-based health literacy principles and conducted through a collaborative partnership between industry and academia professionals. The PPI was then tested in four focus groups, two in Atlanta and two in Chicago, with an emphasis on collecting feedback from respondents with limited health literacy, evaluated using the Newest Vital Sign (NVS) health literacy assessment tool. Subsequent comprehension testing included patients with C. diff, caregivers, and general population members, with a pre-defined target sample of 25% with limited health literacy identified through two health literacy assessment tools: the Single Item Literacy Screener and the NVS. RESULTS: Content development of the bezlotoxumab PPI occurred in May 2015. In June 2015, focus group respondents (n = 34) provided generally favorable feedback, with insights revolving around organization and usability; language and comprehension; and volume of information. Comprehension testing of the revised PPI resulted in average comprehension scores of 96% for the overall population (n = 59), 90% for individuals presenting with limited health literacy (n = 14), and 97% for those with adequate health literacy (n = 45). This PPI development approach was similarly effective for subsequent products across diverse therapeutic areas, with comprehension scores ≥ 86% for all participants (n = 1197). CONCLUSION: This methodology represents a significant advancement for the development of understandable patient medication labeling, especially for people with limited health literacy.