Transitioning from Fixed-Length Questionnaires to Computer-Adaptive Versions

Abstract

To investigate how an existing questionnaire can be transformed into a computer-adaptive version, we developed an adaptive version of the Interpersonal Competence Questionnaire (ICQ). This adaptive version was based on a representative sample (N = 1934) of respondents who answered 30 items from a German translation of the ICQ. A random half of the sample was used to evaluate test dimensionality, calibrate the items, and model the relation between person parameters and raw total scores. The other random half of the sample was employed to assess the comparability of person parameters and raw scores. After these tests and item calibration, 28 items remained in the item pool. A high correlation was found between raw scores and estimated scores using all items. Raw scores could be predicted accurately from estimated person parameters. These results indicate that our approach is an effective technique for transforming an existing questionnaire into a computer-adaptive version.