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Related Experiment Video

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Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity

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Intraclass correlations: uses in assessing rater reliability.

P E Shrout¹, J L Fleiss

¹Division of Biostatistics Columbia University, School of Public Health, New York, USA.

Psychological Bulletin

|March 1, 1979

Summary

This study provides guidelines for selecting the appropriate intraclass correlation coefficient for reliability studies involving multiple judges. It helps researchers choose the best measure based on statistical models and intended applications.

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Area of Science:

Psychometrics
Statistical Modeling
Research Methodology

Background:

Reliability coefficients are crucial for assessing measurement consistency.
Intraclass correlation coefficients (ICCs) are commonly used for this purpose.
Selecting the correct ICC form is essential for accurate reliability assessment.

Purpose of the Study:

To offer guidance on choosing among six forms of the intraclass correlation coefficient.
To assist researchers in reliability studies involving multiple judges and targets.
To clarify the influence of statistical models and application contexts on ICC selection.

Main Methods:

Review of six different forms of the intraclass correlation coefficient.
Analysis of statistical models relevant to reliability studies.
Examination of application-specific considerations for reliability results.

Main Results:

Guidelines are provided for selecting the most appropriate ICC form.
The choice of ICC is influenced by the underlying statistical model.
The intended application of reliability results is a key factor in selection.

Conclusions:

Proper selection of the intraclass correlation coefficient enhances the validity of reliability studies.
Understanding the nuances of different ICC forms is critical for researchers.
Confidence intervals for each ICC form are discussed to aid interpretation.