|Geographical unita||Number of unitsb||Description and sources of geographical data|
|Municipalities||1,063||Municipalities (as determined by provincial legislation) or an area that is deemed to be equivalent to a municipality for statistical reporting purposes (e.g. cities, cantons). Source: Statistics Canada, 2006.|
|Census consolidated subdivisions||903||Grouping of adjacent census subdivisions. Generally the smaller, more urban census subdivisions (towns, villages, etc.) are combined with the surrounding, larger, more rural census subdivision in order to create a geographic level between the census subdivision and the census division. Source: Statistics Canada, 2006.|
|Census divisions||97||Groups of neighboring municipalities joined together for the purposes of regional planning and managing common services (such as police or ambulance services). Source: Statistics Canada, 2006.|
|CLSC||155||Local community service center (CLSC) districts, which are the smallest health-related geographical division in Quebec. CLSC has the mission to provide local front-line health and social services to their population. Source: Quebec’s ministry of health and social services, 2004.|
|Watershed||71||Drainage area boundaries at the sub-sub-basin level based on classic drainage basins having certain minimum volume of mean annual discharge. Source: Government of Canada, Natural Resources Canada, Canada Centre for Remote Sensing, The Atlas of Canada, 2007. Boundaries of watersheds were adjusted to fit the boundaries of the municipalities to avoid misalignment between population and covariate data (see  for more details).|
|Smallest||1,119||Units equivalent to municipality or CLSC depending on which is the smaller.|
|Agriculture||319||Aggregated adjacent units from the smallest framework based on similar covariate patterns for presence of poultry production, presence of ruminant agricultural production and use of pasture (see  for more details).|
Geographical units for the study of campylobacteriosis spatial distribution in Quebec, Canada.
a Geographical units were hierarchical within the same framework (i.e. administrative, health services and custom), but not between frameworks.
b Number of units are for the studied area.
Arsenault et al.
Arsenault et al. BMC Infectious Diseases 2012 12:318 doi:10.1186/1471-2334-12-318