A CAT (Critically Appraised Topic) is a short summary of the best available evidence on a focused question. It is a shorter, less rigorous type of systematic review, providing an assessment of what is known about an intervention or issue by searching and appraising relevant studies.
Because it is faster than a full SR, a CAT does have limitations in terms of comprehensiveness and so is much more prone to selection bias than a systematic review or a rapid review. But they have an important role to play in supporting evidence based practice – identifying gaps in the knowledge, quickly scoping the literature and informing policy.
CATs have been used since the 1990s, mainly in the fields of veterinary science, physiotherapy, occupational therapy, dermatology, urology, radiology, nursing, business management and education.
Like any type of systematic review, a certain methodology should be followed. Even though CATs are quick, compared to other reviews, they should still follow these steps:
Brennan, M. L., Arlt, S. P., Belshaw, Z., Buckley, L., Corah, L., Doit, H., Fajt, V. R., Grindlay, D., Moberly, H. K., Morrow, L. D., Stavisky, J., & White, C. (2020). Critically Appraised Topics (CATs) in Veterinary Medicine: Applying Evidence in Clinical Practice. Frontiers in veterinary science, 7, 314. https://doi.org/10.3389/fvets.2020.00314