Creating injury episodes using medical claims data

Background: Health care episodes are traditionally created for a specific condition using defined relevant diagnosis and procedure codes and a start and end period. Our goal is to use 1987 to 1989 medical claims data to create distinct episodes of care as a result of injury. Methods: Claims for 102,000 people younger than 65 years were obtained from Medstat Systems, Inc. Injury claims were identified by International Classification of Diseases, 9th Revision, Clinical Modification diagnosis codes and separated into 10 body regions. Using linked inpatient and outpatient claims data, we established clear zones-a maximum period for a return visit for medical treatment-for each of 10 body regions injured by hospitalization status. These clear zones were used to create episodes of injury. Results: A total of 295,165 injury claims created 79,564 episodes of injury. Limb and trunk injuries typically have the most follow-ups in terms of number of claims and spacing between claims. Brain injuries, even far admitted patients, result in an average of fewer than two follow-up claims. On average, hospitalized patients require only one more follow-up than nonadmitted patients. Conclusions: This paper presents a method for identifying injury episodes using a medical claims database. The analysis suggests that follow-up to check for minor long-term sequelae of brain injury is rare.