Patients With Limited Health Literacy Have Similar Preferences but Different Perceptions in Surgical Decision-making for Carpal Tunnel Release.

BACKGROUND: Health literacy is the ability to obtain, process, and understand health information needed to make appropriate health decisions. The proper comprehension by patients regarding a given disease, its treatment, and the physician's instructions plays an important role in shared decision-making. Studies have disagreed over the degree to which differences in health literacy affect patients' preferences for shared decision-making; we therefore sought to evaluate this in the context of shared decision-making about carpal tunnel release. QUESTIONS/PURPOSES: (1) Do patients with limited health literacy have different preferences of shared decision-making for carpal tunnel release than those with greater levels of health literacy? (2) How do patients with limited health literacy retrospectively perceive their role in shared decision-making after carpal tunnel release?
METHODS: Over a 32-month period, one surgeon surgically treated 149 patients for carpal tunnel syndrome. Patients were eligible if they had cognitive and language function to provide informed consent and complete a self-reported questionnaire and were not eligible if they had nerve entrapment other than carpal tunnel release or had workers compensation issues; based on those, 140 (94%) were approached for study. Of those, seven (5%) were lost to followup before 6 months, leaving 133 for analysis here. Their mean age was 55 years (range, 31-76 years), and 83% (111 of 133) were women. Thirty-three percent (44 of 133) of patients had less than a high school education. Health literacy was measured according to the Newest Vital Sign during the initial visit, and a score of ≤ 3 was considered limited health literacy. Forty-four percent of patients had limited health literacy. The Control Preferences Scale was used for patients to indicate their preferred role in surgical decision-making preoperatively and to assess their perceived level of involvement postoperatively. Bivariate and multivariable analyses were performed to determine whether patients' clinical, demographic, and health literacy factors accounted for the preoperative preferences and postoperative assessments of their role in shared decision-making. A total of 133 patients would provide 94% power for a medium effect size for linear regression with five main predictors.
RESULTS: We found no differences between patients with lower levels of health literacy and those with greater health literacy in terms of preferences of shared decision-making for carpal tunnel release (3.0 ± 1.6 versus 2.7 ± 1.4; mean difference, 0.3; 95% confidence interval, -0.2 to 0.8; p = 0.25). A history of surgical procedures (coefficient = -0.32, p < 0.01) and a lower Disabilities of the Arm, Shoulder and Hand score (coefficient = 0.17, p = 0.02) were independently associated with a preference for an active role in shared decision-making. However, patients with limited health literacy (coefficient = -0.31, p = 0.01) and an absence of a caregiver (coefficient = -0.28, p = 0.03) perceived a more passive role in actual decision-making.
CONCLUSIONS: Physicians should be aware of the discrepancy between preferences and perceptions of shared decision-making among patients with limited health literacy, and physicians should consider providing a decision aid tailored to basic levels of health literacy to help patients achieve their preferred role in decision-making. LEVEL OF EVIDENCE: Level II, prognostic study.