Jämför metoder

	Kortformsanalys av differentiell itemfunktion (Kortforms-DIF)	Testning av mätinvarians
Ämnesområde	Psykometri	Psykometri
Familj	Latent structure	Latent structure
Ursprungsår	1970s–1990s (DIF); short-form context developed in parallel with scale abbreviation literature	2000
Upphovsperson	Angoff, W. H. and subsequent DIF methodologists	Vandenberg & Lance
Typ	Item bias / measurement fairness analysis	Multi-group confirmatory factor analysis procedure
Ursprungskälla	Millsap, R. E. (2012). Statistical Approaches to Measurement Invariance. Routledge. ISBN: 978-0-8058-4507-0	Vandenberg, R. J., & Lance, C. E. (2000). A review and synthesis of the measurement invariance literature. Organizational Research Methods, 3(1), 4–70.
Alias	Short-form DIF, abbreviated scale DIF, DIF in short forms, short-scale DIF detection	Factorial Invariance, Measurement Equivalence, Configural-Metric-Scalar Testing, Ölçüm Değişmezliği
Närliggande	6	3
Sammanfattning	Short-form differential item functioning (DIF) analysis examines whether individual items in an abbreviated scale function equivalently across demographic or subgroup comparisons. When a scale is shortened, retained items must still behave fairly for all relevant groups — DIF analysis verifies this, ensuring that score differences reflect true ability or trait differences rather than item bias.	Measurement invariance testing is a sequence of nested confirmatory factor analysis (CFA) models that examines whether a psychological scale measures the same latent construct in the same way across distinct groups or time points. Systematized and popularized by Vandenberg and Lance (2000), the procedure tests a hierarchy of constraints — from identical factor patterns to identical item intercepts — so that researchers can justify meaningful group comparisons on latent means.