Background: Low health literacy (HL) is associated with poor healthcare outcomes; mechanisms for these associations remain unclear.
Objective: To elucidate how HL influences patients' interest in participating in healthcare, medical visit communication, and patient reported visit outcomes.
Design, setting, and patients: Cross-sectional study of enrollment data from a randomized controlled trial of interventions to improve patient adherence to hypertension treatments. Participants were 41 primary care physicians and 275 of their patients. Prior to the enrollment visit, physicians received a minimal intervention or communication skills training and patients received a minimal intervention or a pre-visit coaching session. This resulted in four intervention groups (minimal patient/minimal physician; minimal patient/intensive physician; intensive patient/minimal physician; and intensive patient/intensive physician).
Measurements: Rapid Estimate of Adult Literacy in Medicine; patients' desire for involvement in decision making; communication behaviors; patient ratings of participatory decision making (PDM), trust, and satisfaction.
Results: A lower percentage of patients with low versus adequate literacy had controlled blood pressure. Both groups were similarly interested in participating in medical decision making. Communication behaviors did not differ based on HL except for medical question asking by patients, which was lower among low literacy patients. This was particularly true in the intensive patient /intensive physician group (3.85 vs. 6.42 questions; p = 0.002). Overall, ratings of care didn't differ based on HL; however, in analyses stratified by intervention assignment, patients with low literacy in minimal physician intervention groups reported significantly lower PDM scores than adequate literacy patients.
Conclusions: Patients with low and adequate literacy were similarly interested in participating in medical decision making. However, low literacy patients were less likely to experience PDM in their visits. Low literacy patients in the intensive physician intervention groups asked fewer medical questions. Patients with low literacy may be less able to respond to physicians' use of patient-centered communication approaches than adequate literacy patients.