Abstract: Database of patient specific electronic health records indexed by ICD or CPT medical coding protocols or similar. The indexing allows organization of the patient's records within the database by health diagnoses, treatments or tests. This method facilitates rapid searching and retrieval of past diagnoses, etc. for utilization in diagnosis, treatment or testing of the patient in subsequent medical events. The method allows a clinician or health care provider to rapidly learn whether a patient has a history of prior treatment for the symptoms now experienced. The software and method can be utilized to search billing records wherein the ICD or similar codes have been recorded and then match the coded events to events contained in the patient's EHR database. This allows searching of the EHR database utilizing diagnosis, treatment and test codes in situations where old patient records stored in the database have not adopted the code indexing.