Development of a Novel Validated Tool for Predicting Patient Adherence to Prescribed Medication

Patient nonadherence to medication harms patient outcomes and raises costs via wasted and unnecessary treatment (Osterberg and Blaschke, 2005). However, current adherence measures are far from optimal (Vitolins et al., 2000), and adherence enhancing interventions rarely successful (Haynes et al., 2008). This may be a reflection of inadequate patient targeting and adherence measurement. This thesis describes the development of questionnaires intended to be clinically useful by predicting patient risk of nonadherence. A scoping review with meta-analysis was undertaken to identify predictors objectively shown to be associated with nonadherence. Any pre-existing questionnaires to measure the selected predictors were identified via literature review. Pre-existing questionnaires incorporated were the Beliefs about Medicines Questionnaire (Horne et al., 1999), Perceived Stress Scale (Cohen et al., 1983), Patient Health Questionnaire (Kunik et al., 2007), and the Patient-Doctor Relationship Questionnaire (Van der Feltz-Cornelis et al., 2004). Novel items were developed to measure patient demographics, health literacy, mental health, risky health behaviours, beliefs about medicines, self-efficacy , social support, and access to medicines. These scales were incorporated into two novel questionnaires. The Patient and Lifestyle Scale (PALS), and the Wellbeing and Medications Scale (WAMS). A feasibility study was conducted with 16 patients at a GP surgery to identify limitations in research design and perform preliminary psychometric assessment. Issues with participant identification were highlighted, however, indications were that PALS and WAMS could be used to predict self-reported and prospective refill adherence. A practitioner focus group appraised the clinical utility of the questionnaires whilst acceptability and validity were assessed via six participant interviews. The PALS and WAMS were perceived to be potentially clinically useful and most items were considered acceptable. Findings also indicated that mental distress is associated with nonadherence and that long term adherence may depend more upon integrating medicines into every day habits than rational cost-benefits appraisals.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of East Anglia

Year dc:date.issued

2013

Author dc:creator

• Watson, Steven

Language dc:language

en