What's in a Scale - Multidimensionality or Wording Artifact? A Comprehensive Psychometric Analysis of the Rasch-Type...

Area of Science:

• Psychometrics
• Psychological Measurement
• Social Psychology

Background:

• The Rasch-Type Loneliness Scale (RTLS-6) is widely used to assess emotional and social loneliness.
• Concerns exist regarding the negatively worded items for social loneliness potentially creating artifactual factors.

Purpose of the Study:

• To examine the psychometric properties of the RTLS-6, including its dimensionality and Rasch model conformity.
• To evaluate the impact of response format modifications on scale properties.

Main Methods:

• Three studies (N=4,812 total) analyzed the original and modified RTLS-6 versions using Rasch analyses.
• Dimensionality, Rasch-conformity, and differential item functioning were assessed.

Main Results:

• A robust two-factor structure for emotional and social loneliness was supported, independent of item wording effects.
• Multidimensional, polytomous Rasch analyses indicated a four-point intensity response format is optimal.
• The original RTLS-6 demonstrated good model fit and absence of differential item functioning across subgroups.

Conclusions:

• The RTLS-6 is psychometrically sound as a two-dimensional scale for measuring emotional and social loneliness.
• The scale aligns well with polytomous Rasch model assumptions, supporting its validity and reliability.