1. A method for predicting the weight loss outcome of the application of therapy to a patient for treating an eating, gastrointestinal, or gastroesophageal disorder, comprising: a) obtaining items of information from a patient at risk of one of an eating, gastro-intestinal, and gastroesophageal disorder, each item of information relating to a preselected patient variable; b) predicting a weight loss outcome for the patient from the obtained information for the patient using an aggregated weight loss predictor developed from i) observed similar types of information and corresponding weight loss information obtained from an actual population of patients who previously received a similar therapy to that proposed for the patient, or ii) information generated from a simulated population of patients by resampling the observed actual population information to produce pseudo-replicates.