Code

Code for: A common measurement scale for self-report instruments in mental health care: T scores with a normal distribution

Author(s) / Creator(s)

de Beurs, Edwin

Abstract / Description

Code to calculate IRT based T scores and normalised T scores
The diversity of measures in clinical psychology hampers a straightforward interpretation of test results, complicates communication with the patient, and constitutes a challenge to the implementation of measurement-based care. In educational research and assessment, it is common practice to convert test scores to a common metric, such as T scores. We recommend applying this also in clinical psychology and propose and test a procedure to arrive at T scores approximating a normal distribution that can be applied to individual test scores. We established formulas to estimate normalized T scores from raw scale scores by regressing IRT-based θ scores on raw scores. With data from a large population and clinical samples, we established crosswalk formulas. Their validity was investigated by comparing calculated T scores with IRT-based T scores. IRT and formulas yielded very similar T scores, supporting the validity of the latter approach. Theoretical and practical advantages and disadvantages of both approaches to convert scores to common metrics and alternative approaches are discussed. Provided that scale characteristics allow for their computation, T scores will help to better understand measurement results, which makes it easier for patients and practitioners to use test results in joint decision-making about the course of treatment.
Code for: de Beurs, E., Oudejans, S., & Terluin, B. (2022). A common measurement scale for self-report instruments in mental health care: T scores with a normal distribution. European Journal of Psychological Assessment. Advance online publication. https://doi.org/10.1027/1015-5759/a000740

Keyword(s)

IRT T scores percentile ranks common metric clinical norms

Persistent Identifier

Date of first publication

2022-03-16

Publisher

PsychArchives

Is referenced by

Citation

  • Author(s) / Creator(s)
    de Beurs, Edwin
  • PsychArchives acquisition timestamp
    2022-03-30T08:37:47Z
  • Made available on
    2022-03-30T08:37:47Z
  • Date of first publication
    2022-03-16
  • Abstract / Description
    Code to calculate IRT based T scores and normalised T scores
    en
  • Abstract / Description
    The diversity of measures in clinical psychology hampers a straightforward interpretation of test results, complicates communication with the patient, and constitutes a challenge to the implementation of measurement-based care. In educational research and assessment, it is common practice to convert test scores to a common metric, such as T scores. We recommend applying this also in clinical psychology and propose and test a procedure to arrive at T scores approximating a normal distribution that can be applied to individual test scores. We established formulas to estimate normalized T scores from raw scale scores by regressing IRT-based θ scores on raw scores. With data from a large population and clinical samples, we established crosswalk formulas. Their validity was investigated by comparing calculated T scores with IRT-based T scores. IRT and formulas yielded very similar T scores, supporting the validity of the latter approach. Theoretical and practical advantages and disadvantages of both approaches to convert scores to common metrics and alternative approaches are discussed. Provided that scale characteristics allow for their computation, T scores will help to better understand measurement results, which makes it easier for patients and practitioners to use test results in joint decision-making about the course of treatment.
    en
  • Abstract / Description
    Code for: de Beurs, E., Oudejans, S., & Terluin, B. (2022). A common measurement scale for self-report instruments in mental health care: T scores with a normal distribution. European Journal of Psychological Assessment. Advance online publication. https://doi.org/10.1027/1015-5759/a000740
    en
  • Publication status
    unknown
  • Review status
    unknown
  • Persistent Identifier
    https://hdl.handle.net/20.500.12034/5061
  • Persistent Identifier
    https://doi.org/10.23668/psycharchives.5663
  • Language of content
    eng
  • Publisher
    PsychArchives
  • Is referenced by
    https://doi.org/10.1027/1015-5759/a000740
  • Is related to
    https://www.psycharchives.org/handle/20.500.12034/5060
  • Is related to
    https://www.psycharchives.org/handle/20.500.12034/5062
  • Is related to
    https://www.psycharchives.org/handle/20.500.12034/5063
  • Is related to
    https://doi.org/10.1027/1015-5759/a000740
  • Keyword(s)
    IRT
    en
  • Keyword(s)
    T scores
    en
  • Keyword(s)
    percentile ranks
    en
  • Keyword(s)
    common metric
    en
  • Keyword(s)
    clinical norms
    en
  • Dewey Decimal Classification number(s)
    150
  • Title
    Code for: A common measurement scale for self-report instruments in mental health care: T scores with a normal distribution
    en
  • DRO type
    code