Publication

Measuring individual significant change on the Beck Depression Inventory-II through IRT-based statistics

Brouwer, D., Meijer, R. & Zevalkink, J., 1-Sep-2013, In : Psychotherapy research. 23, 5, p. 489-501 13 p.

Research output: Contribution to journalArticleAcademicpeer-review

Several researchers have emphasized that item response theory (IRT)-based methods should be preferred over classical approaches in measuring change for individual patients. In the present study we discuss and evaluate the use of IRT-based statistics to measure statistical significant individual change on the Beck Depression Inventory-II (BDI-II, Beck, Steer, & Brown, 1996). We compare results obtained with a simple IRT-based statistical test (Z-test) to those obtained with the Reliable Change Index (RCI) in a sample of clinical outpatients. Mean group differences between the Z-test and the RCI were similar, but for some individuals change classifications differed. Differences were most evident for change scores within the lower range of depression scores. We show that this may have consequences for the measurement of individual change in psychotherapy outcome research and clinical practice.

Original languageEnglish
Pages (from-to)489-501
Number of pages13
JournalPsychotherapy research
Volume23
Issue number5
Publication statusPublished - 1-Sep-2013

    Keywords

  • item response theory, BDI-II, Z-test, individual change, depression, statistical methodology, test development, ITEM RESPONSE THEORY, PSYCHOTHERAPY OUTCOME RESEARCH, CLINICAL-SIGNIFICANCE METHODS, GAIN SCORES OBSOLETE, PSYCHOMETRIC EVALUATION, RELIABLE CHANGE, PSYCHOPATHOLOGY, PERSONALITY, OUTPATIENTS, PRECISION

ID: 5936789