Importance of the physical exam: double-blind randomized controlled trial of radiologic interpretation of ventral hernias after selective clinical information

Purpose: Increasingly, radiologic imaging is obtained as part of the pathway in diagnosing ventral hernias. Often, radiologists receive incomplete or incorrect clinical information from clinicians. Objective: The aim of the study is to determine if clinical exam findings alter radiological interpretation of ventral hernias on CT. Methods: This is a single-institution double-blind, randomized trial. All patients with a recent abdominal/pelvic CT scan seen in various surgical clinics were enrolled. A surgeon blinded to the CT scan findings performed a standardized physical examination and assessed for the presence of a ventral hernia. Seven independent radiologists blinded to the study design reviewed the scans. Each radiologist received one of three types of clinical exam data per CT: accurate (correct), inaccurate (purposely incorrect), or none. Allocation was random and stratified by the presence of clinical hernia. The primary outcome was the proportion of radiologic hernias detected, analyzed by chi square. Results: 115 patients were enrolled for a total of 805 CT scan reads. The proportion of hernias detected differed by up to 25% depending on if accurate, no, or inaccurate clinical information was provided. Inaccurate clinical data in patients with no hernia on physical exam led to a significant difference in the radiologic hernia detection rate (54.3% versus 35.7%, p = 0.007). No clinical data in patients with a hernia on physical exam led to a lower radiologic hernia detection rate (75.0% versus 93.8%, p = 0.001). Conclusions: The presence and accuracy of clinical information provided to radiologists impacts the diagnosis of abdominal wall hernias in up to 25% of cases. Standardization of both clinical and radiologic examinations for hernias and their reporting are needed. Trial registration: Clinicaltrials.gov, Number NCT03121131, https://clinicaltrials.gov/ct2/show/NCT03121131.