Abstract:

Objective To develop a self-rating scale for drug literacy of patients after percutaneous coronary intervention，and to provide an evaluation tool for evaluating the level of drug literacy of patients after percutaneous coronary intervention. Methods From May to October 2023，the scale items were preliminarily constructed through literature analysis and qualitative interviews based on the conceptual model of drug literacy. The first draft of the scale was formed by two rounds of consultation with 25 experts through the Delphi method. After that，the expression of scale items was improved with the pre-survey of 50 patients after PCI，and 568 patients after PCI in investigation. Then，the scale items were screened and their reliability and validity were tested to form the final version. Results The positive coefficients of the two rounds of expert consultation were 93%（25/27） and 100%（25/25），the expert authority coefficients were 0.906 and 0.944，and the Kendall harmony coefficients were 0.35 and 0.39，respectively. A total of five common factors were extracted by exploratory factor analysis，and the cumulative variance contribution rate reached 77.730%. Confirmatory factor analysis showed a well fit model with χ²/df=2.848，RMSEA=0.076，CFI=0.927，IFI=0.927，and TLI=0.916. The final drug literacy scale for patients after percutaneous coronary intervention included 25 items in five dimensions，including drug belief，functional drug literacy，interactive drug literacy，evaluative drug literacy，and behavioral drug literacy. The content validity index at the item level was 0.880-1.000，and the content validity index at the scale level was 0.917. The Cronbach’s α coefficient，half-fold reliability and test-retest reliability of the total scale were 0.951，0.865 and 0.933，respectively. Conclusion The drug literacy assessment scale of patients after percutaneous coronary intervention holds good reliability and validity，and can be used in the evaluation of drug literacy level of patients after percutaneous coronary intervention.

Key words: Percutaneous coronary intervention, Drug literacy, Reliability, Validity