At MCHP, the effective use of administrative databases is centered around a population-based research registry. This registry contains longitudinal demographic histories for every individual who has registered for the Manitoba Health Services Insurance Plan (MHSIP) since 1970. Each registrant is assigned an encrypted number associated with the following information: demographic characteristics (e.g. age and gender), place of residence (by postal code), and family composition. This number allows researchers to track changes in these characteristics over time.

Substantive files, including vital statistics, information on hospital stays, physician visits and nursing home stays use the same encrypted number to track utilization of services.

Documentation and software are increasingly important as files become more numerous and research possibilities multiply. The outer ring of studies in this figure represent special files - both clinical and survey data - that have been linked to registry files for various projects (e.g. Bernstein et al. 2001¹; Robinson et al. 1997²; Murray et al. 2002³; Mustard et al. 1999⁴).