I am using logit models to predict whether or not children are unhealthy (binary indictor).  Many of my models have statistically significant relationships between predictors of interest (ie, if the child’s household has improved water/sanitation) and the outcome.   However, none of my models outperform a model which just uses demographic information (age, region, urban/rural, sex).  Furthermore, the models are pretty terrible at predicting unhealthy children (only about ~15% true positives correctly predicted, which are about 23% of the data).  Do these two facts render the statistically significant relationships between the predictors and outcome of interest meaningless?  How do I explain this to my (hopefully future) readers?  Thanks,