Fig. (2) Dependency tree analysis of the relationships between gender, dry eyes, dry mouth, chronic rhinosinusitis (CRS), nasal polyps and asthma. Age (in years, centered around 50) was included as a covariate in the model. Odds Ratios (95% CI) are depicted along the edges connecting variables, and all were significant at a p-value < 0.0001. The fitted model was highly significant (likelihood ratio = 799.7, DF = 6, p < 0.0001), and there was no evidence of lack of fit (likelihood ratio = 10.7, DF = 177, p = 1) indicating that further, or higher order, interactions between variables were not substantial. The displayed model can be decomposed into 5 components: (Dry Eyes:Dry Mouth), (CRS:Asthma), (CRS:Nasal Polyps), (CRS:Dry Eyes) and (Gender:Dry Eyes/Age:Dry Eyes/Age).