Survey of patient and physician influences and decision-making regarding CT utilization for minor head injury.

Objective: Assess factors that influence both the patient and the physician in the setting of minor head injury in adults and the decision-making process around CT utilization.

Methods: This is a convenience sample survey study of adult minor head injury patients (GCS 15) and their physicians regarding factors influencing the decision to use CT to evaluate for intra-cranial haemorrhage. Once a head CT was ordered and before the results were known, both the patient and physician were given a one-page survey asking questions about their concern for injury and rationale for CT use. CT results and surveys were then recorded in a centralized database and analyzed.

Results: 584 subjects were enrolled over the 27-month study period. The rate of any intra-cranial haemorrhage was 3.3%. Both the physicians (6% pre-test estimate) and the patients (22% pre-test estimate) over-estimated risk for haemorrhage. Clinical decision rules were not met in 46% of cases where CT was used. Physicians listed an average of 5 factors from a list of 9 that influenced their decision to order CT. Patients listed an average of 1.7 factors influencing their decision to present to the Emergency Department for evaluation. Many patients felt cost (45%) and low risk stratification (34%) should weigh heavily in the decision to use CT. If asked to limit CT utilization, physicians were able to identify a group with less than 2% risk of injury.

Conclusions: Patients with low risk of intra-cranial injury continue to be evaluated by CT. Physician decision-making around the use of CT to evaluate minor head injury is multi-factorial. Shared decision-making between the patient and the physician in a low risk minor head injury encounter shows promise as a method to reduce CT utilization in this low risk cohort.