The analytic methods currently being used for the study of the genetics of asthma have primarily focused on the evaluation of linkage by non-parametric methods as applied to genome screen data in affected sibling pairs. Complexity in the analysis of asthma genetics has been shown to occur at several levels, including phenotypic definition (wide vs narrow criteria for asthma, including restriction based upon multiple phenotypes) and joint analysis of asthma with associated phenotypes. Alternative approaches that purport to treat asthma as a quantitative trait (a ‘score’ or ‘index’) rather than as a qualitative (asthma, yes or no) trait were presented, including the development of a ‘Framingham Risk Score’ for asthma, a selection index, or a propensity score. While each of these alternatives have interesting features, issues relating to estimation and incorporation in a family structure have yet to be resolved. Nonetheless, collection of a standard set of clinical data from multiple studies could be used in a score to increase the power of genetic mapping studies for asthma.