The study is a cross-sectional reliability study at the department of Radiology, Sultan Qaboos University Hospital, Oman. The study included 15 patients who presented to the emergency department with acute lower quadrant pain and underwent CT scan of the abdomen to rule appendicitis. The CT abdomen was done with intravenous and oral contrast. The procedure notes and histopathology reports were traced to confirm the status of the appendix.

Six radiologist with different level of experience have participated as reviewers in the study. Three reviewers were junior radiologist (less than one year of experience) and the other three radiologists with more than 6 years of experience.    The investigator used iPhone 6 model smartphone with 8-megapixel camera, 1080p video at 60 frames per second with 1080 x 1920 pixels viewing screen.

    The radiology images were captured as a video. The smartphone was positioned 40 cm away from the center of the monitor and was held still. The lights in the reporting room were dimmed off. No magnification or filter application was applied and the flash light was off. The radiology images at the workstation were played as cine at 15 frames per second while capturing it by smartphone camera. The study was captured fully including the reformatted series available in the study and all patient’s demographic data were removed.    The captured images then were sent to the participating radiologists using WhatsApp.

The reviewers had to comment on images quality, main findings and diagnosis. The appendix was rated either as normal, borderline, inflamed, inflamed with complications or not seen.  Also they were asked to rate their confidence in giving the diagnosis in a percentage scale. The quality of video captured images was graded using absolute visual grading analysis described by Ludewig et el , which is composed of  5 categories¹⁰ (Category one with excellent image quality and no limitation for clinical use whereas category five with poor image quality, not usable with loss of information).

The radiologists re-reviewed the cases 4 weeks later using the radiology reporting workstation ( Philips, Intellispace, version 4.4.516.21, USA  ). The radiologists filled the same form that was used for smartphone method with similar parameters.