MedicineInsight is a novel program from NPS MedicineWise. It is seeking to establish a real-world longitudinal Electronic Health Record (EHR) database. It seamlessly collects practice data to link patient conditions with treatments and their impacts in order to support quality improvement in participating practices. Quality health records can inform better decision making, both for individual patients as well as the capacity for whole-of-practice reflection leading to development of systems for care refinement. They also facilitate safe and reliable sharing of health information to achieve effective patient care. However a health record can only be as good as the information recorded or the coding system allows. Now with experiences in collecting data from more than 250 practices (>1500 GPs), MedicineInsight has gained many insights into the management of general practice patients and the complexity of their care. An example of the power of MedicineInsight data is the simple yet fundamental process of identifying patients with chronic disease and recording of recommended tests. In traditional records, patients with type 2 diabetes (T2DM) are collected through the register function within the EHR. However, given that we know coding of diagnosis and recording rates within discrete fields for relevant biomedical and pathology tests is variable, do we know how many patients with T2DM slip through the cracks?