study validity

Alternate spelling: stratified randomisation. A method for ensuring that an equal number of participants with a characteristic that may influence the prognosis or the response to the intervention will be allocated to each of the compared groups, to reduce the potential for confusion bias. Note: For example, in a breast cancer study, it may be important to have the same proportion for pre-menopausal and post-menopausal women in each group. To that end, the randomisation is done separately for each menopausal status stratum (often using random permuted blocks) or by means of minimization.

scoping review rapid review