Consumers' self-reported adherence to directions for non-prescription medicines and the role of risk perception

Background: Non-prescription medicines (NPMs), while relatively safe, are responsible for a small but significant proportion of medication misadventure and inappropriate use may lead to avoidable healthcare cost. Some consumers vary their use of NPMs from the directions provided on packaging or advice from healthcare professionals. Consumers may use NPMs at lower doses or less frequently than directed because of the risk of side effects. Purpose: This study aimed to develop and validate a self-report measure for the extent to which consumers' follow directions (FDs) for NPMs. Secondly, it aimed to explore the relationship between risk perception towards NPMs and following directions. Methods: A cross-sectional study was administered online to participants who belong to an Australian agency which conducts consumer research. Participants were Australian adults who had used NPMs within the last month. Items for the FD-NPM scale were developed and validated. Exploratory factor analysis and confirmatory factor analysis were used to validate the FD-NPM scale. Structural equation modelling (SEM) was employed to explore the relationships between risk perception, covariates, and FDs. Results: There were 403 participants recruited. Less than 20% always or often self-reported following directions for dose, frequency, or duration of use. Factor analyses confirmed that there are two moderately positively correlated dimensions of FD-NPM (r = 0.46), which were named underuse and overuse. That is, consumers who self-reported underuse of non-prescription medicines were also more likely to self-report overuse. Consumers with high-risk perception towards NPMs, those who were younger and those who were more educated had a greater tendency to not follow directions. Conclusion: A new self-report measure, the FD-NPM scale was developed and validated. That people who perceives NPMs to be harmful, tend to underuse and more concerningly, overuse them, is of great interest to clinicians and policymakers who are required to manage risk communications.

Automated summary

This study developed and validated a self-report measure, the FD-NPM scale, to evaluate the extent to which consumers follow directions when using non-prescription medicines (NPMs). The findings showed that less than 20% of participants always or often followed the dosage, frequency, and duration instructions. Consumers with high-risk perception towards NPMs, younger individuals, and those with higher education were more likely to not follow the directions.