Individual Case Listings are our most popular products. Clients are able to customize the variables used to build the data query to identify the cases of interest. Specific variables may be selected based on a number of specific data parameters related but not limited to: age, weight, gender, medical outcome, or variables providing information about the substance involved. A comprehensive list of variables and definitions can be found in the NPDS Elements table below. Individual Case Listings may be delivered for retrospective or prospective data on a one-time, quarterly, monthly, or other pre-determined interval.