Table 4.

Principal Components Analysis and confirmatory factor analysis (CFA) for PHQ-4. (Factorial Validity)

Four-items of anxiety and depression scale	Component loadings		Goodness-of-fit statistics
	aComponent1	bComponent2	Confirmatory factor analysis
1. Feeling nervous, anxious or on edge	0.834	0.230	CFI = 0.995
2. Not being able to stop or control worrying	0.799	0.272	SRMR = 0.013
3. Little interest or pleasure in doing things	0.333	0.716	RMSEA = 0.054
4. Feeling down, depressed or hopeless	0.186	0.865	90%CI for RMSEA (0.031,0.079)

Note: Extraction method: principal components analysis. Rotation method: varimax;^a Items on anxiety (GAD-2);

^bItems on depression (PHQ-2); Components accounted for 82% of the variance