A computer hardware-implemented method, system, and/or computer program product matches a current patient to a specific patient readmission cohort. The specific patient readmission cohort, made up of patients having a shared attribute, has a historical likelihood of hospital readmission within a predefined post-discharge length of time for members of the specific patient readmission cohort. A database describing a current patient is selected, based on the cost and speed of accessing that database, as well as the probability that the database describes a similar attribute for the current patient as the shared attribute in the specific patient readmission cohort. If the current patient meets the requisite criteria for entry into the specific patient readmission cohort, then a recommendation designed to reduce a likelihood of hospital readmission of the current patient is generated.