Σύγκριση μεθόδων

	Ανθεκτική Αξιοπιστία Επανελέγχου (Test-Retest)	Συντελεστής Άλφα του Cronbach (Ανάλυση Αξιοπιστίας)	Διεκτιμητική Αξιοπιστία (κ του Cohen και ICC)
Πεδίο	Ψυχομετρία	Στατιστική	Ψυχομετρία
Οικογένεια	Latent structure	Latent structure	Latent structure
Έτος προέλευσης	1990s–2000s	1951	1960 (kappa); 1979 (ICC)
Δημιουργός	Built on classical test-retest reliability (Pearson, early 1900s); robust extensions formalized by Wilcox and colleagues from the 1990s onward	Lee J. Cronbach	Cohen (kappa, 1960); Shrout & Fleiss (ICC, 1979)
Τύπος	Reliability / measurement stability	Reliability / internal consistency coefficient	Reliability / agreement analysis
Θεμελιώδης πηγή	Wilcox, R. R. (2012). Introduction to Robust Estimation and Hypothesis Testing (3rd ed.). Academic Press. ISBN: 978-0123869838	Cronbach, L. J. (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16(3), 297–334.	Cohen, J. (1960). A Coefficient of Agreement for Nominal Scales. Educational and Psychological Measurement, 20(1), 37–46.
Εναλλακτικές ονομασίες	robust temporal stability, outlier-resistant retest reliability, robust repeatability coefficient, robust intraclass correlation	coefficient alpha, alpha reliability, internal consistency reliability, Güvenilirlik Analizi (Cronbach Alpha)	inter-rater reliability, interrater agreement, rater agreement, Değerlendiriciler Arası Güvenilirlik (Cohen's κ, ICC)
Συναφείς	3	4	6
Σύνοψη	Robust test-retest reliability quantifies how consistently a measure ranks or scores the same individuals across two occasions while protecting the estimate from distortion by outliers and non-normal score distributions. It replaces or supplements classical Pearson-based correlation and standard ICC formulas with robust estimators of location, scale, and association.	Cronbach's alpha is a coefficient of internal consistency that quantifies the degree to which a set of items on a scale measures the same underlying construct. Introduced by Lee J. Cronbach in 1951, it remains the most widely reported reliability index in social-science, health, and educational research.	Interrater reliability quantifies the degree to which two or more independent raters produce consistent scores when evaluating the same individuals or products. The family encompasses Cohen's kappa, introduced in 1960 for categorical judgments, and the Intraclass Correlation Coefficient (ICC) for continuous ratings, together spanning most measurement scenarios encountered in behavioral, health, and educational research.