A Mokken scale to assess secondary pupils’ experience of violence in terms of severity

Abstract

Violence assessment can potentially be improved by Item Response Theory, i.e. ordinal Mokken Scale Analysis. The research question is: Does Mokken Scale Analysis of secondary pupils’ experience of violence result in a homogeneous, reliable, and valid unidimensional scale that fits all the requirements of Mokken scaling? The method used is secondary analysis of Dutch national data collected from secondary school pupils in 2008 by means of a digital school safety survey. The first random sample (n1=14,388) was used to develop the scale; the second sample (n2=14,350) is meant to cross-validate the first results. Pupils’ experience of violence is assessed by 29 items reflecting six types of antisocial or aggressive behaviour. A Mokken scale of 25 items meets the requirements of monotone homogeneity and double monotonicity. Ordering is invariant between: Boys and girls; being born in the Netherlands or not; and feeling at home in the Netherlands or not. These results are cross-validated in sample 2. The latent construct concerns pupils’ experience of violence in terms of severity, varying from verbal and mild physical violence (relatively most frequent), to combinations of social, material and severe physical violence, to very severe and serious sexual violence (relatively least frequent). Some limitations and further developments are discussed.