The purpose of this mixed methods study is to determine how best electronic personal health records (PHRs) should be designed and used to help patients get the full benefit of their prescribed medication. A convergent parallel mixed methods design will be used, and it is a type of design in which qualitative and quantitative data are collected in parallel, analysed separately and then merged. In this study he qualitative data, such as interview data, will be the dominant and will be used to explore the context-mechanism-outcome relation of patient and disease related barriers of medication adherence and to determine which the most important design features of a PHR are, to improve medication adherence. The quantitative data will be used to enhance the meaning of the qualitative and to assist with the exploration of the phenomenon. The reason for collecting both quantitative and qualitative data is to corroborate results, the two forms of data to bring greater insight into the problem than would be obtained by either type of data separately.