Browsing by Author "Rynhoud, Leigh"

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    Predictors of medication adherence in people hospitalised with tuberculosis: utility of the Health Belief Model
    (2021-12) Rynhoud, Leigh; Kagee, Ashraf; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Psychology.
    ENGLISH ABSTRACT: The purpose of this study was to explore the utility of the Health Belief Model (HBM) to predict adherence to treatment for tuberculosis. The first aim was to develop an appropriate, and freely available instrument to measure tuberculosis medication-taking behaviour. The final scale consisted of four self-reported questions, and one question based on information obtained from reports made by health care-providers. I named this scale the Tuberculosis Adherence Scale (TB-AS). The Cronbach’s alpha calculated for TB-AS was 0.69. The second aim of this study was to construct a questionnaire based on the HBM specific to adherence to tuberculosis medication. I administered the HBM measure to 205 participants. Following an item analysis and exploratory factor analysis, 41 items were retained, and five subscales were extracted. I named the subscales Perceived Threat, Perceived Benefits, Perceived Barriers, Self-Efficacy and Cues to Action. I named the questionnaire the Tuberculosis Health Belief Scale (TB-HBS). The TB-HBS demonstrated excellent internal consistency and produced a Cronbach’s alpha of 0.87. The Cronbach’s alpha for each subscale ranged from 0.72 to 0.81. The final aim of the study was to explore the utility of the HBM and additional variables to predict adherence to tuberculosis treatment. I used a cross sectional design and 175 participants who were hospitalised at two specialised tuberculosis hospitals in the Western Cape, South Africa were recruited. Adherence was measured using the TB-AS, health beliefs using the TB-HBS and beliefs about medicine evaluated by the Beliefs about Medicine Questionnaire, Alcohol use, drug use and depression were assessed using the Alcohol Use Disorders Identification Test, Drug Use Disorder Identification Test and Beck Depression Inventory respectively. The results obtained from the TB-AS indicated that 33.1% of participants had low adherence, 34.3% had medium adherence and 32.5% of participants had high adherence. The HBM factors did not significantly predict adherence and explained an additional 2% of variance when included in the regression analysis. Older age [  = 0.24, t (158) = 3.37, p < 0.01], full time occupation [ = 0.18, t (158) = 2.47, p = 0.01], high belief in the general harm of medication [  = 0.20, t (158) = 2.07, p = 0.04], fewer specific concerns about tuberculosis treatment [  = -0.04, t (158) = -2.11, p = 0.04], lower alcohol use [  = -0.20, t (158) = -2.76, p = 0.01], fewer symptoms of depression [ = -0.16, t (158) = -2.09, p = 0.04] significantly predicted improved adherence to treatment for tuberculosis. The results of the regression analysis indicated that the model explained 21% of the variance in adherence (adj R2 =0.21, F (3, 158) = 5.12, p< 0.01) yielding a moderate effect size (ƒ2 = 0.27). The TB-HBS and the TB-AS showed promise as reliable tools to measure health beliefs and adherence to treatment, respectively. The findings suggest that the HBM may not be an appropriate theoretical model to predict adherence to treatment in this context. Further research is recommended to explore the complex and interacting dimensions that affect adherence to tuberculosis treatment.