Value of Performing a Rasch Analysis on a Reliable and Valid Instrument-Case Study of the SA-SH

J Nurs Meas. 2020 Aug 1;28(2):322-342. doi: 10.1891/JNM-D-18-00106. Epub 2020 May 23.

Abstract

Background and purpose: The aim of this study was to explore the potential added value of performing a Rasch analysis on a reliable and valid instrument employed in nursing research and educational interventions, using the Students' Attitudes toward Sexual Health (SA-SH) as an example.

Methods: This study was performed with a polytomous Rasch model.

Results: The Rasch analysis confirmed the reliability and validity of the SA-SH. Rasch analysis presented information about the item's individual response options and gave the opportunity to judge how well different answers alternated in an item. The Rasch analysis also provided information about the proportion of extremes and the possibility of excluding these.

Conclusions: The Rasch analysis provides added value regarding information that needs to be considered regarding choices of questionnaire literacy compared to item fit. The SA-SH is also valid and reliable when tested with Rasch analysis.

Keywords: Rasch analysis; nursing; psychometrics; sexual health; validity.

MeSH terms

  • Adult
  • Data Interpretation, Statistical
  • Female
  • Health Surveys / standards*
  • Humans
  • Male
  • Nursing Research / standards*
  • Nursing Research / statistics & numerical data*
  • Psychometrics / standards*
  • Reproducibility of Results
  • Research Design
  • Sexual Health / statistics & numerical data*
  • Students, Nursing / psychology*
  • Surveys and Questionnaires / standards*
  • Young Adult