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Agala, C. Bernard; Fried, Bruce J.; Thomas, James C.; Reynolds, Heidi W.; Hassmiller Lich, Kristen; Whetten, Kathryn D.; Zimmer, Catherine R.; & Morrissey, Joseph P. (2020). Reliability, Validity and MeasurementĀ Invariance of the Simplified Medication Adherence Questionnaire (SMAQ) among HIV-Positive Women in Ethiopia: A Quasi-Experimental Study. BMC Public Health, 20, 567. PMCID: PMC7189687


BACKGROUND: Adherence to antiretroviral therapy is critical to the achievement of the third target of the UNAIDS Fast-Track Initiative goals of 2020-2030. Reliable, valid and accurate measurement of adherence are important for correct assessment of adherence and in predicting the efficacy of ART. The Simplified Medication Adherence Questionnaire is a six-item scale which assesses the perception of persons living with HIV about their adherence to ART. Despite recent widespread use, its measurement properties have yet to be carefully documented beyond the original study in Spain. The objective of this paper was to conduct internal consistency reliability, concurrent validity and measurement invariance tests for the SMAQ.
METHODS: HIV-positive women who were receiving ART services from 51 service providers in two sub-cities of Addis Ababa, Ethiopia completed the SMAQ in a HIV treatment referral network study between 2011 and 2012. Two cross-sections of 402 and 524 female patients of reproductive age, respectively, from the two sub-cities were randomly selected and interviewed at baseline and follow-up. We used Cronbach's coefficient alpha (


Reference Type

Journal Article

Year Published


Journal Title

BMC Public Health


Agala, C. Bernard
Fried, Bruce J.
Thomas, James C.
Reynolds, Heidi W.
Hassmiller Lich, Kristen
Whetten, Kathryn D.
Zimmer, Catherine R.
Morrissey, Joseph P.

Article Type









Thomas, JC - 0000-0002-2225-2052
Hassmiller Lich - 0000-0002-3311-4202