Migraine screen questionnaire: further psychometric evidence from categorical data methods

Table 2 Univariate descriptive statistics, closeness to dimensionality measures, communality and factor loadings of the Migraine Screen-Questionnaire (MS-Q) scores in Ethiopian university students

Items of the MS-Q	Skewness	kurtosis	Item-total Correlations^a	I-ECV	IREAL	Communality (h²)^b	Factor loading^b
Do you have frequent or intense headaches?	0.259	−1.930	.75^*	0.913	0.247	0.707	0.798
Do your headaches usually last more than 4 h?	1.158	−0.660	.68^*	0.885	0.303	0.797	0.835
Do you usually suffer from nausea when you have a headache?	1.289	−0.340	.65^*	0.999	0.030	0.688	0.802
Does light or noise bother you when you have a headache?	0.454	−1.791	.76^*	0.816	0.428	0.914	0.848
Does headache limit any of your physical or intellectual activities?	−0.012	−1.997	.76^*	0.977	0.118	0.662	0.781

^*p < 0.01
^a Spearman’s correlation coefficient
^b Diagonally weighted least squares for unrotated solution
I-UniCo Item Unidimensional Congruence, I-ECV Item Explained Common Variance
I-REAL Item Residual Absolute Loadings

ISSN: 1477-7525