OBJECTIVE: This study examined the psychometric properties of the ASK-20 questionnaire, which was developed to assess barriers to medication adherence. RESEARCH DESIGN AND METHODS: Patients with asthma, diabetes, and congestive heart failure were recruited from a university medical center. Participants in this convenience sample completed the ASK-20 questionnaire and other questionnaires. Approximately one-third of participants were randomized to a 2-week retest administration. Analyses examined the reliability and validity of the ASK-20. RESULTS: A total of 112 patients participated (75.9% female; mean age = 46.7 years). The ASK-20 had good internal consistency reliability (Cronbach's alpha = 0.76) and test-retest reliability (0.80). Concurrent validity was demonstrated through significant correlations with the Morisky Medication Adherence Scale (r = -0.61, p < 0.001), condition-specific measures, and the SF-12 Mental Component Summary score (r = -0.40, p < 0.001). The correlation of the ASK-20 with proportion of days covered by filled medication prescriptions in the past 6 months (based on pharmacy claims) was relatively weak (r = -0.13), but in the expected direction. The ASK-20 total score significantly discriminated among groups of patients who differed in self-reported indicators including the Morisky score; missing a medication dose in the past week; number of days medication was not taken as directed; and treatment satisfaction. CONCLUSION: The ASK-20 demonstrated adequate reliability and validity, and it may be a useful measure of barriers to treatment adherence across a spectrum of chronic diseases. Limitations related to scale construction, lack of longitudinal data, and item characteristics are discussed.
RCT Entities:
OBJECTIVE: This study examined the psychometric properties of the ASK-20 questionnaire, which was developed to assess barriers to medication adherence. RESEARCH DESIGN AND METHODS: Patients with asthma, diabetes, and congestive heart failure were recruited from a university medical center. Participants in this convenience sample completed the ASK-20 questionnaire and other questionnaires. Approximately one-third of participants were randomized to a 2-week retest administration. Analyses examined the reliability and validity of the ASK-20. RESULTS: A total of 112 patients participated (75.9% female; mean age = 46.7 years). The ASK-20 had good internal consistency reliability (Cronbach's alpha = 0.76) and test-retest reliability (0.80). Concurrent validity was demonstrated through significant correlations with the Morisky Medication Adherence Scale (r = -0.61, p < 0.001), condition-specific measures, and the SF-12 Mental Component Summary score (r = -0.40, p < 0.001). The correlation of the ASK-20 with proportion of days covered by filled medication prescriptions in the past 6 months (based on pharmacy claims) was relatively weak (r = -0.13), but in the expected direction. The ASK-20 total score significantly discriminated among groups of patients who differed in self-reported indicators including the Morisky score; missing a medication dose in the past week; number of days medication was not taken as directed; and treatment satisfaction. CONCLUSION: The ASK-20 demonstrated adequate reliability and validity, and it may be a useful measure of barriers to treatment adherence across a spectrum of chronic diseases. Limitations related to scale construction, lack of longitudinal data, and item characteristics are discussed.
Authors: Martha Sajatovic; Dawn I Velligan; Peter J Weiden; Marcia A Valenstein; Gbenga Ogedegbe Journal: J Psychosom Res Date: 2009-07-25 Impact factor: 3.006
Authors: Lisa M Hooper; Lauren E Huffman; John C Higginbotham; George C T Mugoya; Annie K Smith; Tia N Dumas Journal: Community Ment Health J Date: 2017-04-05
Authors: Ricardo N Angeles; Dale Guenter; Lisa McCarthy; Martha Bauer; Miriam Wolfson; Maria Chacon; Lana Bullock Journal: Pain Res Manag Date: 2013-07-19 Impact factor: 3.037