Patients' expectancy scale of acupuncture: Development and clinical performance test.

PURPOSE: This study aims to develop and validate a concise tool for evaluating acupuncture expectancy that is easy to understand and conforms to acupuncture characteristics. MATERIALS AND METHODS: A draft was created using the Delphi consensus method. Reliability, validity, discrimination, and feasibility tests were conducted at the item and scale levels. RESULTS: The scale themes were defined as disease-related, treatment-related, process-related, and outcome-related. After two rounds of Delphi surveys with good experts' reliability (authority coefficients of experts were 0.86 and 0.87 in the two rounds) and agreement (Kendall's concordance coefficient of the participants were 0.33 and 0.15 in the two rounds, P < 0.05), 11 items (the mean score for item importance, full mark ratios, and coefficient of variation of items were ≥3.5, ≥25%, and ≤0.30, respectively) were included in the draft. A total of 145 individuals were recruited to test the draft. Reliability was assessed by Cronbach's α coefficient (0.90), split-half reliability coefficient (0.89), and test-retest reliability (Pearson's coefficient = 0.74, P < 0.05). Content validity was assessed by the content validity index (Item-CVI ≥ 0.78 and Scale-CVI/Ave = 0.92), and a confirmatory factor analysis was performed to assess the construct validity. The discrimination of scale items was evaluated by the critical ratio (CR > 3.00) and the homogeneity test (item-total correlations >0.40). Feasibility was assessed through the acceptance rate (recovery rate = 98.60%, response rate = 100%), completion rate (100%), and completion time (4.99 ± 6.80 min). CONCLUSION: The patients' expectancy scale of acupuncture (PESA) consists of 11 items with four themes, disease-related, treatment-related, process-related, and outcome-related. It has great reliability, validity, discrimination, and feasibility and has the potential to evaluate acupuncture expectancy in clinical trials.