Fig. 2From: Latent variable mixture models to test for differential item functioning: a population-based analysisWithin-class item response percentages for the SF-36 mental health (MH) sub-scale items. Legend: The selected best-fit latent variable mixture model had two classes. Response categories of “all of the time”, “most of the time” and “good bit of the time” were combined due to low frequencies. MH3 and MH5 were reverse coded in the analysisBack to article page