Permuted block design
An approach to generating an allocation sequence in which the number of assignments to intervention groups satisfies a specified allocation ratio (such as 1:1 or 2:1) after every "block" of specified size.
For example, a block of size 12 would contain 6 A and 6 B with a ratio of 1:1 or 8 A and 4 B with a ratio of 2:1. Generating the allocation sequence involves randomly selecting from all the permutations of assignments that meet the specified ratio.
Page last edited: 01 March 2007
