Table 2.

Model fit statistics for unitary (unidimensional), pentagonal (multidimensional), and bifactor models of psychosis based on PANSS, YMRS and MADRS symptom ratings

	LL	FP	AIC	BIC	SABIC
Unidimensional (unitary) model (Model A)	–35660.2	153	71626.4	72354.2	71868.3
Multidimensional (pentagonal) model with five correlated specific factors (Model B)	–33615.3	163	67556.5	68331.9	67814.3
Bifactor model with one general factor and five specific symptom factors (Model C)	–33253.0	204	66914.1	67884.5	67236.6
Bifactor model with one general factor, two factors for non‐affective and affective psychosis, and five specific symptom factors (Model D)	–32739.2	255	65988.4	67201.4	66391.6
Bifactor model with two factors for non‐affective and affective psychosis and five specific symptom factors (model E)	–33372.9	204	67153.7	68124.2	67476.3

PANSS – Positive and Negative Syndrome Scale, YMRS – Young Mania Rating Scale, MADRS – Montgomery‐Åsberg Depression Rating Scale, LL – log‐likelihood, AIC – Akaike information criterion, BIC – Bayesian information criterion, SABIC – sample size‐adjusted Bayesian information criterion. All response vectors with at least one response were analyzed (N=860). Model D provides the best model fit, as indicated by lower BIC, AIC and SABIC compared to other models.