Random assignment of treatments in a 96-well (8 X 12) microtiter plate. A practical method

A computer program, written in BASIC, has been developed to assign treatments strictly at random to the wells of a microtiter plate. A hard copy is printed of the treatment numbers with their assigned wells, followed by an 8 X 12 matrix of the treatment numbers. When a microtiter plate is placed over the matrix these numbers may be viewed directly through the wells. A program listing is reproduced. The effects of randomization on within-plate variation have been investigated and compared with two systematic methods of assignment.