Table 1.

Categories of genetic test applications and some characteristics of how clinical validity and utility are assessed

Application of test	Clinical validity	Clinical utility
Diagnosis (symptomatic patient)	Association of marker with disorder	Improved clinical outcomesa—health outcomes based on diagnosis and subsequent intervention or treatment
		Availability of information useful for personal or clinical decision-making
		End of diagnostic odyssey
Disease screening (asymptomatic patient)	Association of marker with disorder	Improved health outcome based on early intervention for screen positive individuals to identify a disorder for which there is intervention or treatment, or provision of information useful for personal or clinical decision making
Risk assessment/susceptibility	Association of marker with future disorder (consider possible effect of penetrance)	Improved health outcomes based on prevention or early detection strategies
Prognosis of diagnosed disease	Association of marker with natural history benchmarks of the disorder	Improved health outcomes, or outcomes of value to patients, based on changes in patient management
Predicting treatment response or adverse events (pharmacogenomics)	Association of marker with a phenotype/metabolic state that relates to drug efficacy or adverse drug reactions	Improved health outcomes or adherence based on drug selection or dosage

^aClinical outcomes are the net health benefit (benefits and harms) for the patients and/or population in which the test is used.