Factor analysis and validity of the Transplant Evaluation Rating Scale in a large bone marrow transplant sample

Clinical and methodological challenges are involved in screening bone marrow transplant (BMT) recipients for pretransplant psychosocial adjustment in an attempt to anticipate and prevent behavioral difficulties. Validity of the Transplant Evaluation Rating Scale (TERS), which quantifies the disparate salient elements in a structured clinical assessment, has not been adequately established. This study comprehensively investigated three questions about convergent, internal-structural, and predictive validity of the TERS: how indicative the TERS is of psychosocial difficulties; whether the TERS is uni- or multidimensional; to what degree the TERS predicts long-range adjustment during recovery posttransplant.

Pre-BMT, 345 consecutive patients were prospectively assessed and completed the MMPI. TERS ratings were assigned retrospectively by two raters (interrater reliability r=.89).

The TERS showed good convergent validity relative to MMPI subscales, and a clear, simple, two-factor structure accounting for 47% of the variance. On a subset of our sample (n=29), the factor subscales, "Defiance" and "Emotional Sensitivity," exhibited differential predictive validity to functional status at 1 year posttransplant.

This study, the first large-scale statistical investigation of TERS validity, provided evidence for the validity of the TERS on all three questions. The TERS is indeed indicative of psychosocial risk indexed by MMPI behavioral pathology. It has an understandable, clinically useful factor structure. Its subordinate constructs, Defiance and Emotional Sensitivity, can and should be distinguished conceptually and measured separately. The TERS has clinical utility for specifying behavioral concerns before and guiding proactive intervention after BMT.