1. A computer implemented process comprises: producing by one or more computers plural sets of training data that comprise words associated with multiple groups of individuals, with the multiple groups being of individuals having different classifications of mental states that define a like number of multiple cohorts; executing by one or more computers a classification model using the training data to classify a first group of individuals in relation to a second, different group of individuals, with the first and second groups of individuals being of the multiple groups of individuals, and different ones of the multiple cohorts; determining by one or more computers points of intersection of words between the first group and the second group of individuals; determining by one or more computers words in the training data that are unique to the first group of individuals to provide isolated statistically predictive terms for the first group to identify predictive features for a first cohort; and determining by one or more computers words in the training data that are unique to the second group of individuals to provide isolated statistically predictive terms for the second group to identify predictive features for a second one of the cohorts.