Side Effect Perceptions and Their Impact on Treatment Decisions in Women

Background. Side effects prompt some patients to forego otherwise-beneficial therapies. This study explored which characteristics make side effects particularly aversive. Methods. We used a psychometric approach, originating from research on risk perception, to identify the factors (or components) underlying side effect perceptions. Women (N = 149) aged 40 to 74 years were recruited from a patient registry to complete an online experiment. Participants were presented with hypothetical scenarios in which an effective and necessary medication conferred a small risk of a single side effect (e.g., nausea, dizziness). They rated a broad range of side effects on several characteristics (e.g., embarrassing, treatable). In addition, we collected 4 measures of aversiveness for each side effect: choosing to take the medication, willingness to pay to avoid the side effect (WTP), negative affective attitude associated with the side effect, and how each side effect ranks among others in terms of undesirability. A principal components analysis (PCA) was used to identify the components underlying side effect perceptions. Then, for each aversiveness measure separately, regression analyses were used to determine which components predicted differences in aversiveness among the side effects. Results. The PCA revealed 4 components underlying side effect perceptions: affective challenge (e.g., frightening), social challenge (e.g., disfiguring), physical challenge (e.g., painful), and familiarity (e.g., common). Side effects perceived as affectively and physically challenging elicited the highest levels of aversiveness across all 4 measures. Conclusions. Understanding what side effect characteristics are most aversive may inform interventions to improve medical decisions and facilitate the translation of novel biomedical therapies into clinical practice.