Regression Analysis of CT Head Examinations Without Contrast.

Computed tomography (CT) examination of the head without contrast can be used to help assess head injuries, severe headaches, dizziness, and other symptoms of aneurysm, bleeding, stroke, and brain tumors. It also helps doctors evaluate a patient’s face, sinuses, and skull, and might be used to plan radiation therapy for brain cancer. In emergency cases, it can reveal internal injuries and bleeding quickly enough to help save lives. This study assessed trends in pathological findings for patients who underwent CT head examinations without contrast to determine whether the findings were related to sex, indication for head CT, and hospital campus. To evaluate the relationship, linear regressions were analyzed for linearity, sample variation in the explanatory variable, and zero mean of the error term conditional on the independent variable.