title: Validity testing of the Long-Term Medication Behavior Self-Efficacy Scale.
abstract: Self-efficacy is an important determinant of health behavior that can be targeted for intervention. Little effort has been given to the development of valid measures for self-efficacy with medication taking for adherence research. The purpose of this study was to determine the criterion validity of the Long-Term Medication Behavior Self-Efficacy Scale (LTMBSES). Individual patient data from 6 existing adherence studies in transplant, hyperlipidemia, and AIDS/HIV patients (n = 1021) were pooled. Validity was determined by assessing the relation between the LTMBSES score and medication adherence--both self-reported and electronically monitored. A weak relationship was found between the LTMBSES score and adherence, which can possibly be attributed to a ceiling effect, caused by a too homogeneous population and/or a failure of the scale to challenge patients. Generalized Estimating Equations revealed that the total average self-efficacy score predicted reported medication adherence (p < .0001). The Receiver Operating Characteristic curve revealed the area under the curve was 0.67, indicating a significant (p < .0001), but poor predictive capability. Evidence for criterion validity of the Long-Term Medication Behavior Self-Efficacy Scale is not yet convincing. Future research should focus on: (1) validation in a population with a more heterogenous level of adherence, and (2) making the scale more challenging by referring to "always taking the medication without exception."
authors.affiliation: University of Basel, Basel, Switzerland.
authors.forename: Kris
authors.initials: K
authors.lastname: Denhaerynck
authors.forename: Ivo
authors.initials: I
authors.lastname: Abraham
authors.forename: Greta
authors.initials: G
authors.lastname: Gourley
authors.forename: Gerda
authors.initials: G
authors.lastname: Drent
authors.forename: Peter
authors.initials: P
authors.lastname: De Vleeschouwer
authors.forename: Doreen
authors.initials: D
authors.lastname: Papajcik
authors.forename: Elaine
authors.initials: E
authors.lastname: Lince
authors.forename: Sabina
authors.initials: S
authors.lastname: De Geest
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001530:Belgium; D002908:Chronic Disease / Q000188:drug therapy*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010349:Patient Compliance; D011581:Psychological Tests; D015203:Reproducibility of Results; D020377:Self Efficacy; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D014481:United States