"My patients are better than yours": optimistic bias about patients' medication adherence by European health care professionals

Objectives: The objectives of this study were to determine the perceptions of European physicians, nurses, and pharmacists about the extent of nonadherence by patients in their country relative to their perception of nonadherence by their own patients, and to investigate the occurrence of optimistic bias about medication adherence. The study explored a key cognitive bias for prevalence and likelihood estimates in the context of health care professionals' beliefs about patients' use of medicines. Methods: A cross-sectional online survey of 3,196 physicians (855), nurses (1,294), and pharmacists (1,047) in ten European countries (Austria, Belgium, England, France, Germany, Hungary, the Netherlands, Poland, Portugal, and Switzerland) was used. Results: Participants differed in their perceptions of the prevalence of medication adherence initiation, implementation, and persistence present in their own patients with a chronic illness in comparison to patients with a chronic illness in general. Health care professionals demonstrated optimistic bias for initiation and persistence with medicine taking, perceiving their own patients to be more likely to initiate and persist with treatment than other patients, but reported significantly lower prevalence of medication adherence levels for their own patients than for patients in general. This finding is discussed in terms of motivational and cognitive factors that may foster optimistic bias by health care professionals about their patients, including heightened knowledge of, and positive beliefs about, their own professional competence and service delivery relative to care and treatment provided elsewhere. Conclusion: Health care professionals in Europe demonstrated significant differences in their perceptions of medication adherence prevalence by their own patients in comparison to patients in general. Some evidence of optimistic bias by health care professionals about their patients' behavior is observed. Further social cognitive theory-based research of health care professional beliefs about medication adherence is warranted to enable theory-based practitioner-focused interventions to be tested and implemented.