Challenges and benefits of assessment, diagnosis, and taxonomy for clinical practice and research

Objective: To outline nosological (top-down) and empirically based (bottom- up) approaches to assessment and taxonomy of psychopathology. Method: The two approaches were compared and contrasted to highlight simila rities and differences between them. Results and Conclusions: To advance services and research, we need to make optimal use of assessment data (i) to identify the distinguishing features of each case, and (ii) to link individual patterns of functioning with taxo nomic constructs that can help us apply previously accumulated knowledge to new cases. The time may be ripe for integrating nosological and empiricall y based approaches. One way to integrate these approaches is to construct e mpirically based and DSM-oriented scales from the same item pools and to ge nerate age- and gender-specific standard scores and cut-off points from the same normative samples. Integration of the approaches was illustrated with profiles of empirically based and DSM-oriented scales scored from the same item pools and quantified in relation to the same normative samples. To fa cilitate use by clinicians and researchers under diverse conditions, data a re readily obtained on forms completed independently by parents, teachers a nd others. The data can be quickly scored by hand or computer. To take acco unt of situational and informant variations, the computer software systemat ically compares data from multiple informants on empirically based and DSM- oriented scales.