Σύγκριση μεθόδων

	Αξιοπιστία Επανάληψης-Ελέγχου (Test-Retest) Πολυεπίπεδων Δεδομένων	Θεωρία Γενικευσιμότητας (G-Theory)
Πεδίο	Ψυχομετρία	Ψυχομετρία
Οικογένεια	Latent structure	Latent structure
Έτος προέλευσης	1979 (ICC foundation); multilevel extension: 1990s–2000s	1963–1972
Δημιουργός	Shrout & Fleiss (ICC foundation); multilevel extension by Goldstein, Snijders, and others	Lee J. Cronbach, Goldine Gleser, Harinder Nanda, Nageswari Rajaratnam
Τύπος	Reliability estimation under hierarchical data	Variance-components reliability model
Θεμελιώδης πηγή	Shrout, P. E. & Fleiss, J. L. (1979). Intraclass correlations: Uses in assessing rater reliability. Psychological Bulletin, 86(2), 420–428.	Cronbach, L. J., Gleser, G. C., Nanda, H. & Rajaratnam, N. (1972). The Dependability of Behavioral Measurements: Theory of Generalizability for Scores and Profiles. Wiley.
Εναλλακτικές ονομασίες	hierarchical test-retest reliability, multilevel ICC reliability, nested test-retest reliability, ML-TRT reliability	G-theory, G-study / D-study framework, variance components reliability
Συναφείς	5	4
Σύνοψη	Multilevel test-retest reliability estimates how consistently a measurement instrument produces the same scores across repeated administrations when observations are nested within higher-level units — such as patients within clinics or students within classrooms. It partitions total score variance across levels using intraclass correlation coefficients derived from multilevel models.	Generalizability Theory is a psychometric framework that decomposes observed score variance into multiple sources — persons, items, raters, occasions, and their interactions — using analysis of variance. It replaces the single reliability coefficient of classical test theory with a family of coefficients that tell researchers how well scores generalize across different measurement conditions.