In one medical research paper, Proitsi et al. (2009) write: > "The WLSMV is a robust estimator which does not assume normally > distributed variables and provides the best option for modelling > categorical or ordered data (Brown, 2006)". For your convenience, I'm including the cited reference in the reference list below (I use APA format): Brown, T. (2006). _Confirmatory factor analysis for applied research._ New York: Guildford. Proitsi, P., Hamilton, G., Tsolaki, M., Lupton, M., Daniilidou, M., Hollingworth, P., ..., Powell, J. F. (2009, in press). A multiple indicators multiple causes (MIMIC) model of behavioural and psychological symptoms in dementia (BPSD). _Neurobiology Aging_. doi:10.1016/j.neurobiolaging.2009.03.005 I hope this is helpful and answers your question.