Compara mètodes

	Omega de McDonald adaptat per a proves adaptatives computeritzades	Alpha de Cronbach per a proves adaptatives computaritzades
Camp	Psicometria	Psicometria
Família	Latent structure	Latent structure
Any d'origen	1999 (omega); CAT application 2000s–2010s	1984
Autor original	Roderick P. McDonald (omega); CAT-omega application extended by IRT and psychometric reliability researchers	Adapted from Cronbach (1951); CAT reliability framing developed by Green, Bock, Humphreys, Linn & Reckase (1984)
Tipus	Reliability coefficient for adaptive tests	Reliability / internal consistency estimation
Font seminal	McDonald, R. P. (1999). Test Theory: A Unified Treatment. Lawrence Erlbaum Associates. ISBN: 978-0805830408	Green, B. F., Bock, R. D., Humphreys, L. G., Linn, R. L., & Reckase, M. D. (1984). Technical guidelines for assessing computerized adaptive tests. Journal of Educational Measurement, 21(4), 347–360.
Àlies	CAT omega reliability, omega in adaptive testing, hierarchical omega for CAT, CAT composite reliability	CAT reliability estimation, adaptive test internal consistency, CAT coefficient alpha, reliability in CAT
Relacionats	5	3
Resum	McDonald's omega adapted for computerized adaptive testing (CAT) quantifies the reliability of ability or trait estimates when different examinees answer different subsets of items. Unlike Cronbach's alpha, omega is grounded in a factor model, making it suitable for the heterogeneous item pools and variable test lengths that characterize adaptive administrations.	Cronbach's alpha applied to computerized adaptive test (CAT) data estimates internal consistency reliability under the special condition that different examinees receive different subsets of items. Because the classic formula assumes every respondent answers the same items, its direct application to CAT data violates core assumptions and typically underestimates or misrepresents true reliability, requiring careful adaptation or replacement with IRT-based reliability indices.