NDSS - NDSS Description - The Model

The Model

The NDSS is a cost effective approach of utilizing existing provincial and territorial administrative data sources. The clinical path of diabetes detection and treatment makes it particularly amenable for tracking through interactions with the provincial and territorial health care systems.

The NDSS involves linking these existing to develop longitudinal clinical histories of individual cases. Data provided to Health Canada by the provinces and territories are in an aggregate form.

Attributes of the NDSS system

• Distinct roles and responsibilities for provinces and territories, the federal government, Aboriginal groups, and other parties
• A shared data dictionary for coordinating and comparing the administrative databases across provinces and territories
• Three domains of measurement: descriptive epidemiology, complications and co-morbidities, and health services utilization
• A discrete set of outcomes related to health services and health status that can generally be implemented across most provinces and territories
• Ability to produce annual person-specific summarizations of health services and health status information for surveillance purposes
• The option of using various case definitions
• A series of aggregate datasets that reflect the major domains of measurement and measured outcomes, and a strategy for sharing data with parties outside the provinces or territories where the person-specific data are held
• Software to run the system
• The ability to conduct longitudinal analyses

Validating the Model

The applicability of the NDSS's model was tested in a demonstration project undertaken in Manitoba, Saskatchewan and Alberta. The project was undertaken in partnership with the University of Alberta. Matching funds for the project were awarded through Health Canada's Health Infostructure Support Program with significant in-kind work from Manitoba and Saskatchewan.

The project tested the core operations of the NDSS's national model, and fielded inter-government agreements for surveillance activities using provincial health-administration data. This demonstration project successfully generated diabetes surveillance information about:

• incidence;
• prevalence;
• incidence of the complications of diabetes;
• health services used by people with diabetes.

The Data System

Physician claims, administrative hospital records and insurance coverage files are the sources of data.

Person-level data will remain with each Province and Territory, and data on population groups (i.e., aggregated data) will be sent to Health Canada for analysis and national comparison.

Standardized methods will be used to determine diabetes prevalence, incidence and mortality across Provinces and Territories.

The system is designed to estimate diabetes complications (e.g., amputations), and diabetes-associated mortality including rate-ratios for populations with and without diabetes. Epidemiologic and statistical models will be used to compare use of health services between those that have and have not been diagnosed with diabetes.