Σύγκριση μεθόδων

	Short-Form IRT	Διαφορική Λειτουργία Αντικειμένου (DIF)
Πεδίο	Ψυχομετρία	Ψυχομετρία
Οικογένεια	Latent structure	Latent structure
Έτος προέλευσης	1980s–2000s	1970s–1993
Δημιουργός	Multiple contributors; IRT adapted to short-form contexts from Lord & Novick (1968) and subsequent applied psychometricians	William H. Angoff and colleagues (ETS); systematized by Holland & Wainer
Τύπος	Latent trait / item calibration model	Item-level bias detection
Θεμελιώδης πηγή	Embretson, S. E. & Reise, S. P. (2000). Item Response Theory for Psychologists. Lawrence Erlbaum Associates. ISBN: 978-0805828191	Holland, P. W. & Wainer, H. (Eds.) (1993). Differential Item Functioning. Lawrence Erlbaum Associates. ISBN: 978-0805809589
Εναλλακτικές ονομασίες	SF-IRT, abbreviated scale IRT, short-form calibration, shortened instrument IRT	DIF, item bias analysis, measurement non-equivalence, item-level measurement bias
Συναφείς	6	5
Σύνοψη	Short-form item response theory applies IRT calibration and scoring to abbreviated or shortened psychological scales. It uses item information functions to guide which items to retain from a full-length instrument, then estimates latent trait scores from the reduced item set while preserving psychometric rigor and linkage to the full-scale metric.	Differential item functioning identifies test or survey items that behave differently for examinees from different groups — such as gender, ethnicity, or language background — after controlling for the underlying ability or trait being measured. DIF analysis is essential for fairness evaluation in educational testing and psychological scale development.