Adherence to standards for judging the content validity of health measures and for labeling them is needed for the field of health assessment to proceed in an orderly fashion. This paper discusses the dimensionality of health and the range of health states that can be measured within each dimension. These two attributes of published definitions of health are used to derive minimum standards for judging the validity of health measures in terms of their content. Five generic health concepts are defined: physical health, mental health, social functioning, role functioning, and general health perceptions. Items from widely used health measures are presented to clarify distinctions among these concepts and the different health states they encompass. It is recommended that labels be assigned to health measures in a manner consistent with their content and other evidence of validity.