Background: Longitudinal studies of the clinical high risk (CHR) syndrome for psychosis have emphasized the conversion vs non-conversion distinction and thus far have not focused intensively on classification among non-converters. The present study proposes a system for classifying CHR outcomes over time when using the Structured Interview for Psychosis-risk Syndromes and evaluates its validity.
Method: The system for classifying CHR outcomes is referred to as "current status specifiers," with "current" meaning over the month prior to the present evaluation and "specifiers" indicating a set of labels and descriptions of the statuses. Specifiers for four current statuses are described: progression, persistence, partial remission, and full remission. Data from the North American Prodromal Longitudinal Study were employed to test convergent, discriminant, and predictive validity of the current status distinctions.
Results: Validity analyses partly supported current status distinctions. Social and role functioning were more impaired in progressive and persistent than in remitted patients, suggesting a degree of convergent validity. Agreement between CHR current statuses and current statuses for a different diagnostic construct (DSM-IV Major Depression) was poor, suggesting discriminant validity. The proportion converting to psychosis within a year was significantly higher in cases meeting progression criteria than in those meeting persistence criteria and tended to be higher than in those meeting full remission criteria, consistent with a degree of predictive validity.
Discussion: CHR syndrome current status specifiers could offer a potentially valid and useful description of current clinical status among non-converters. Study in additional samples is needed.
Keywords: Clinical high risk; Course of illness; Current status; Psychosis; Risk syndrome.
Copyright © 2014. Published by Elsevier B.V.