Disclosed is a computerized decision support system and method for a) tracking participation within programs, b) capturing participant's participation activity and assessment information in a format that can be easily analyzed and c) distilling the participation and assessment data into useful management and evaluation information. The repository of longitudinal data can be analyzed and reported for case-management and program-evaluation purposes. An assessment module enables analyzable assessment instruments to be custom-defined by the system user, e.g. a program manager. The customized assessment instrument is used to provide answer-restricted questions during an assessment interview, enabling virtually any data item to be tracked historically. The system captures date/time-stamped participation information at various levels of detail and stores this information in a way that can be easily retrieved and analyzed for program and participant-focused analysis. A set of industry-standard participation events can be tracked, with supporting detail, as well as less-data-intensive ad hoc user-defined activities. The data model underlying the system, and the implementation of this model within a relational database system, provides a great degree of flexibility, adaptability and efficient navigation through the database for analysis and reporting. Though numerous program-evaluation reports are provided, a set of intermediary aggregations of data is also available for efficient evaluation of additional program outcome measures.