The forgotten component of the quality triad: can we still learn something from "structure"?

Quality assessment was founded on structural measures, such as accreditation status of facilities, credentialing of providers, and type of provider. Recent efforts in measures development have focused on processes and outcomes because research has suggested that structural measures are not strong markers of the quality of care at the health plan or provider levels. Nevertheless, the literature on the quality of health care contains a number of examples illustrating the potential application of structural measures to the assessment of quality. The continued development of measures of structure-which would at least measure aspects of the physical environment, working conditions, organizational culture, and provider satisfaction--may be helpful because generalizing from studies of process and outcome requires specification of the conditions under which these linkages are found.

The Leapfrog Group of large purchasers has promoted the application of three patient safety "leaps" that are, in essence, structural measures: the use of computerized physician order entry, the selective referral of patients to high-volume providers for certain procedures, and the availability of board-certified critical care specialists in intensive care units. Structural measures, like process and outcomes measures, face the same challenges of standardization, reliability, validity, and portability. Field testing of potential measures will be required to examine the feasibility and added value of these measures in real-world settings.

Research to date suggests that a new cadre of structural measures of health care quality, which have largely been overlooked in the recent measures development boom, have the potential to fill in important gaps in our ability to assess quality.