手法を比較

	項目応答理論 (IRT)	確認的因子分析（CFA）
分野	心理測定学	心理測定学
系統	Latent structure	Latent structure
提唱年	1952–1968	1969
提唱者	Frederic M. Lord (and Allan Birnbaum for the 2PL/3PL models)	Karl Gustav Jöreskog
種類	Probabilistic measurement model	Hypothesis-testing latent variable model
原典	Lord, F. M. & Novick, M. R. (1968). Statistical Theories of Mental Test Scores. Addison-Wesley.	Jöreskog, K. G. (1969). A general approach to confirmatory maximum likelihood factor analysis. Psychometrika, 34(2), 183–202.
別名	IRT, latent trait theory, item characteristic curve theory, modern test theory	CFA, confirmatory FA, measurement model, restricted factor analysis
関連	5	4
概要	Item response theory models the probability that a respondent answers an item correctly (or endorses it) as a function of the respondent's latent trait level and the item's own statistical properties — difficulty, discrimination, and guessing. Unlike classical test theory, IRT places persons and items on the same scale, yielding measurement that is sample-independent for items and test-independent for persons.	Confirmatory factor analysis tests a researcher-specified factor structure against observed data. Unlike exploratory approaches, the researcher decides in advance which indicators load on which latent factor, and the model is evaluated by how closely the implied covariance matrix reproduces the sample covariance matrix. CFA is central to scale validation, construct validity assessment, and measurement invariance testing.