EHR-based phenotype development and validation are extremely time-consuming and have considerable monetary cost. The creation of a phenotype currently requires clinical experts and experts in the data to be queried. The new approach presented here demonstrates a computational alternative to the classification of patient cohorts based on automatic weighting of ICD codes. This approach was applied to data from six different clinics within the University of Arkansas for Medical Science (UAMS) health system. The results were compared with phenotype algorithms designed by clinicians and informaticians for asthma and melanoma. Relative to traditional phenotype development, this method shows potential to considerably reduce time requirements and monetary costs with comparable results.