Considerations of Unobserved Heterogeneity in Internet-Based Survey Data

Sampling of study participants via the Internet assumes that individuals recruited through the same source websites constitute a homogeneous study population.  The data, however, can reflect multiple distributions of risk behavior and exposure data that are combined to reflect a single distribution given the absence of directly-observed grouping variables.  Contemporary analytic techniques, such as latent class analysis (LCA), provide an opportunity to model participant heterogeneity which can improve analytic precision and validity.