IMPACT (Information Medically Pertinent in Acute Computed Tomography) requests: Delphi study to develop criteria standards for adequate clinical information in computed tomography requests in the Australian emergency department.

Introduction: Inadequate clinical information in medical imaging requests negatively affects the clinical relevance of imaging performed and the quality of resultant radiology reports. Currently, there are no published Australian guidelines on what constitutes adequate clinical information in computed tomography (CT) requests. This study aimed to determine specific items of clinical information radiologists require in CT requests for acute chest, abdomen and blunt trauma examinations, to support optimal reporting.

Methods: A panel of 24 CT-reporting consultant radiologists participated in this e-Delphi consensus study. Panellists undertook multiple online survey rounds of open-ended, dichotomous and Likert scale questions, receiving feedback following each. Round 1 responses formulated lists for each CT examination. Round 2 set a threshold of 80% agreement after dichotomous scoring. Round 3 accepted items which averaged 4 or more on a 5-point Likert scale. Round 4 required panellists to rank items within the aggregated, accepted lists, based on panellists' perceived level of usefulness.

Results: The large numbers of round 1 items (chest: 101, abdomen: 76, blunt trauma: 80) were rationalised and grouped into categories to facilitate efficiency during subsequent rounds. Twenty-three chest, 24 abdomen and 17 blunt trauma items met the 80% agreement threshold in round 2. Items below threshold were included in round 3; numbering 44, 19 and 23 for chest, abdomen and blunt trauma, respectively. Through the e-Delphi process, we formulated clinical information criteria standards for three CT types.

Conclusions: The developed standards will guide Australian referrers in providing adequate clinical information in CT requests, to support optimal reporting, diagnosis and treatment.