Linear models for the analysis of variability in factorial designs: an application to anthropometric indicators

This paper has two aims. One is to evaluate, in a set of 9740 'reference' neonates born in five Italian centres (Trieste, Milan, Parma, Rome, Bari) during 1973-1976 the effects of gestational age and birthplace on the variability of crown-heel length and head circumference at birth; this is a preliminary step in the construction of 'Italian' intrauterine growth standards for such anthropometric measures. The other aim is to put the various techniques for the analysis of variability into a common framework of Linear Models, either Generalized or Classical, to compare their main features and provide some indications about their application.