Appropriateness of imaging modality choice by doctors at the Kenyatta National Hospital's Accident and Emergency Department.

Background: Clinical imaging guidelines assist doctors in selecting the most appropriate radiological investigation(s) according to the patient's clinical presentation and also help to avoid unnecessary radiation exposure.

Objectives: This study aimed to determine the appropriateness of choice of imaging procedures requested by the doctors in the Accident and Emergency Department (A&E) of Kenyatta National Hospital (KNH).

Method: Request forms sent to the KNH Radiology Department from the A&E Department from 01 July 2019 to 31 October 2019 were captured digitally. The request forms were de-identified to ensure confidentiality of patients and requesting doctors. Only the demographic data, clinical summary and radiological examination requested were extracted.

Results: A total of 1053 imaging request forms were captured and analysed using the American College of Radiology (ACR) appropriateness criteria. Adequate clinical summary was provided in 81.3% of the request forms. Appropriate imaging requests were 51.9% whilst inappropriate imaging requests were 34.6%. The clinical scenarios of 13.6% of the imaging requests were not found in the ACR database. Imaging modalities using ionising radiation formed the bulk of the inappropriate investigations at 72.8%. Of these, CT scan had the highest individual inappropriate requests of 49.3%. Only 18.4% of female patients in the reproductive age group had a documented last menstrual period.

Conclusion: Imaging modalities using ionising radiation had the highest percentage of inappropriate radiological requests, especially CT scans requested in the trauma setting. In addition, some clinical scenarios were not captured in the ACR appropriateness criteria, hence the need for local imaging guidelines.