obervational studies

prospective studies

retrospective studies

case control studies - retrospective observational study comparing people with a disease/outcome (cases) to similar people without it (controls) to identify past exposures that might explain the condition

cohort study principles

odds ratio

cross-sectional studies

longitudinal studies

randomised controlled trials

Ethics

research that use human smapls must have ethical approval before reserach can begin. wrhical approval must be obtained from the univeristy ethical board or NHS ethical comittee

relevent materials - any tissue or sampels that consists of or contains human cells except embroynic

bodily materials - any tissue or sampels that consists of or contains human cells from the living or decesed for DNA analysis