Cross-cultural adaptation and validation of the Recognizing And Addressing Limited Pharmaceutical Literacy (RALPH) interview guide in community pharmacies.

Background: The RALPH (Recognizing and Addressing Limited PHarmaceutical Literacy) interview guide makes it possible to identify patients with limited pharmaceutical knowledge and to assess their skills in the functional, communicative, and critical health literacy domains.

Objective: (s): To perform a cross-cultural validation of the RALPH interview guide in Spanish population; to conduct a descriptive analysis based on patients' responses.

Methods: A cross-sectional study of patients' pharmaceutical literacy skills was conducted in three stages: systematic translation, administration of the interview and analysis of psychometric properties. The target population included adult patients (≥18 years) who attend one of the participating community pharmacies in Barcelona (Spain). Content validity was evaluated by an expert committee. Viability was assessed in the pilot test, and reliability was assessed using internal consistency and intertemporal stability. Construct validity was assessed by factor analysis.

Results: A total of 103 patients were interviewed at 20 pharmacies. Cronbach's alpha values based on standardized items ranged between 0.720 and 0.764. For the longitudinal component, the ICC test-retest reliability was 0.924. The factor analysis was verified by KMO (0.619) and Bartlett's test of sphericity (P-value <0.05). The definitive RALPH guide translated into Spanish maintains the same structure as the original. Some expressions were simplified, and the questions on the comprehension of warnings or specific instructions for use, contradictory information and shared decision-making were reformulated. Pharmaceutical literacy skills were seen to be most limited with regard to the critical domain. The responses of the Spanish patients were in agreement with the original results of the RALPH interview guide.

Conclusions: The RALPH interview guide in Spanish complies with the requirements viability, validity, and reliability. This tool may be able to identify the low pharmaceutical literacy skills of patients coming to community pharmacies in Spain, and its use may also be extended to other Spanish-speaking countries.