Laboratory formularies.

Clinical laboratories face increasing costs along with increased expectation to ensure appropriate use of diagnostic tests by physicians. One administrative mechanism that has been used successfully for this purpose is the laboratory formulary. Modeled after drug formularies, this is simply a list of diagnostic tests approved for use in a particular setting, possibly including additional restrictions regarding who may order a particular test and under what circumstances. This brief review summarizes the principles underlying laboratory formularies and suggests strategies for using them effectively.