Читать книгу The Pocket Guide to Critical Appraisal - Iain K. Crombie - Страница 29

A special type of cohort treatment study is the quasi‐randomised study. In this design patients are assigned by the researchers to treatment groups using a non‐random method such as date of clinic appointment (assignment by alternate days) or date of birth (assignment by odd or even dates). Because the assignment process is predictable, it could be tampered with, creating a risk of bias. This design is best viewed as similar to an RCT, but one at high risk of bias due to poor concealment of treatment allocation.