Today, our CHIP Prediction Rule was published in Annals of Internal Medicine (Ann Intern Med 2007;146:397-405).
We developed the CHIP Prediction Rule in a large cohort of minor head injury patients from our multicentre “CT in Head Injury Patients” (CHIP) study. The rule may be used as a decision-making aid for the selective use of CT in these patients. We estimate that implementation of the rule in clinical practice may reduce the number of CT scans performed for minor head injury by up to 30%, while still identifying most patients with intracranial traumatic findings on CT and nearly all patients requiring neurosurgical intervention.
The CHIP prediction rule is also applicable to minor head injury patients without a history of loss of consciousness, as opposed to the previously published New Orleans Criteria (N Engl J Med 2000;343:100-105) and the Canadian CT Head Rule (Lancet 2001;357:1391-1396).
A note of caution: we have only validated the prediction rule internally, using bootstrapping methods; external validation, however, is still required.
Our online calculator provides the prediction rule score and the predicted probability of an intracranial traumatic finding on CT in a specific minor head injury patient.