The last 100 consecutive and anonymized MRI investigations for primary perianal fistula reported according to standard practice by dedicated radiologists (the last 10 reports from each of 10 international centers) are reviewed blindly and independently by two experienced radiologists (based on case load, years of experience and publications on anal fistula) using a novel template incorporating 8 key descriptors.

A third independent experienced radiologist will resolve any disagreement and assess the presence of descriptors in the original report compared to the novel template.

Magnetic resonance imaging

The 100 MRI investigations (100 original reports and 100 using the novel template) are sent to 20 experienced surgeons (10 randomly selected reports per surgeon, of which 5 reported conventionally and 5 using the novel template), who will complete a semistructured e-mail interview to collect in-depth information about any barriers and facilitators to implementation of the novel template, and ultimately explore surgical decision making.