Clinical Prediction Rules (CPRs) are developed to quantify the contribution of a patient's history, physical examination or laboratory results and assist physicians to decide a diagnosis, prognosis or treatment strategy. CPRs are disseminated through published scientific articles. An electronic register of CPRs (eCPR) relevant to primary care has been designed and developed to support the wider adoption of CPRs amongst physicians and to provide researchers with ready access to CPRs. The design and development process of eCPR 1.0 followed a problem-centred Design Science Research Process (DSRP) approach. This iterative process involved a number of meetings with stakeholders, demonstration sessions and evaluation pilots. The eCPR was evaluated for its usefulness using the 30-item Usefulness, Satisfaction, and Ease of use (USE) questionnaire conducted during individual pilots with nine general practitioners as potential users. While the functionality of the eCPR 1.0 met the requirements, users' feedback revealed that its interface and user interaction had room for improvements. This led to the development of eCPR 2.0 following the simple interaction design lifecycle model. This study concludes that while the functionality of a health IT solution is pivotal to its success, its user interaction and user experience play a critical role in its adoption by users.