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Precision and Sample Size Requirements for Regression-Based Norming Methods for Change Scores.

ABSTRACT: To interpret a person's change score, one typically transforms the change score into, for example, a percentile, so that one knows a person's location in a distribution of change scores. Transformed scores are referred to as norms and the construction of norms is referred to as norming. Two often-used norming methods for change scores are the regression-based change approach and the T Scores for Change method. In this article, we discuss the similarities and differences between these norming methods, and use a simulation study to systematically examine the precision of the two methods and to establish the minimum sample size requirements for satisfactory precision.

SUBMITTER: Gu Z

PROVIDER: S-EPMC7885019 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Precision and Sample Size Requirements for Regression-Based Norming Methods for Change Scores.

Gu Zhengguo Z Emons Wilco H M WHM Sijtsma Klaas K

Assessment 20200426 2

To interpret a person's change score, one typically transforms the change score into, for example, a percentile, so that one knows a person's location in a distribution of change scores. Transformed scores are referred to as norms and the construction of norms is referred to as norming. Two often-used norming methods for change scores are the regression-based change approach and the <i>T</i> Scores for Change method. In this article, we discuss the similarities and differences between these norm ...[more]

PMID: 32336114

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