Responsiveness of the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test in measuring functional outcomes for inpatient pediatric rehabilitation

Responsiveness is quickly becoming a critical criterion for the selection of outcomes measures in studies of treatment effectiveness, economic appraisals, and other program evaluations. Statistical characteristics, specifically "large effect sizes," are often felt to indicate the relative worth of one instrument over another. However, debates about their meaning led the present authors to propose a taxonomy for responsiveness based on the context of the study concerned. The three axes underlying the classification system relate to: who is this being analyzed for (individuals or groups); which scores are being contrasted (over time/at one point in time); and the type of change being quantified (for example, observed change or important change). It is concluded that responsiveness should be considered a highly contextualized attribute of an instrument, rather than a static property and should be described only in that way. A questionnaire could thus be described as being "responsive to" a given category in the new taxonomy.

Over the last 15 years, numerous self-report health status measures have appeared in the literature. An important parallel development has been the development of numerous strategies for assessing change in health status over time. The purpose of this article is to summarize and critique the more common design and analytic strategies for assessing the meaningfulness of change over time. Five commonly reported designs are presented, critiqued, and depicted using examples from the literature. Methods for analyzing results are reviewed and illustrated using two data sets. Insights into comparing competing health status measures are provided. In summary, the article suggests that some designs and analytic strategies are more adept than others at assessing change and that these methods should be considered when planning sensitivity-to-change studies.

The aims of the study were to: (1) build new item banks for a revised version of the Pediatric Evaluation of Disability Inventory (PEDI) with four content domains: daily activities, mobility, social/cognitive, and responsibility; and (2) use post-hoc simulations based on the combined normative and disability calibration samples to assess the accuracy and precision of the PEDI computer-adaptive tests (PEDI-CAT) compared with the administration of all items.