SigmaAnalytics & Tech
F1SPSSAdvancedAbout 30 min to complete

Reliability Analysis

Internal consistency and what Cronbach's alpha actually measures.

Slides · Dataset

About 30 minutes to complete

Enrol to open the slides and download the data.

What this module covers

internal consistency and what Cronbach's alpha actually measures; alpha thresholds and why 0.95 is a warning rather than a triumph; reverse scoring before you run it, not after; the menu path; reading the output - item-total correlations and alpha-if-item-deleted - and the discipline of not deleting items just to raise alpha; McDonald's omega and when to prefer it; split-half; intraclass correlation for inter-rater reliability, including choosing the right ICC model; test-retest; how to report reliability.

By the end of it

  • Internal consistency and what Cronbach's alpha actually measures
  • Alpha thresholds and why 0.95 is a warning rather than a triumph
  • Reverse scoring before you run it, not after
  • Reading the output - item-total correlations and alpha-if-item-deleted - and the discipline of not deleting items just to raise alpha
  • McDonald's omega and when to prefer it
  • Intraclass correlation for inter-rater reliability, including choosing the right ICC model
  • How to report reliability

The dataset

Maternal health knowledge, attitude and practice scale — Sigma teaching dataset

A teaching dataset of 240 cases, generated from a fixed seed so every figure in the module reproduces exactly.

  • CodebookIncluded
  • Dataset (CSV)Included
  • SPSS syntaxIncluded
  • CodebookIncluded
  • Dataset (CSV)Included
  • SPSS syntaxIncluded