Methods: Tuberculosis in Canada 2012

Methods

Overview of the Canadian Tuberculosis Reporting System

In Canada, active TB disease is monitored at the national level through the Canadian Tuberculosis Reporting System (CTBRS). The CTBRS is a case-based surveillance system that maintains selected non-nominal data on people diagnosed with active TB disease including, but not limited to:

• demographics (e.g. age, sex, immigration status)
• clinical and treatment information
• diagnostic information
• risk-factor information (e.g. HIV status)
• treatment outcome details

Provincial and territorial public health authorities voluntarily submit data on all new and re-treatment cases of active TB disease that meet the Canadian case definition (Appendix 2). Treatment outcome data for new active and re-treatment cases are submitted between 12 and 18 months following the submission of the initial case report. If treatment is ongoing at the time of data submission to the Agency, the reporting jurisdiction submits an interim report followed by subsequent annual updates until the case file is closed.

Five of the 13 jurisdictions (Alberta, Manitoba, Ontario, Quebec, and Saskatchewan) submit case data electronically. The remaining provinces and territories submit case data using the national TB paper reporting forms (Appendix 7). Alberta, Manitoba, Ontario, and Saskatchewan submit outcome data electronically. The remaining jurisdictions submit outcome data using paper reporting forms (Appendix 7). Standardized data recoding procedures were applied to all data to create a national data set for analysis. Pre-coded standard response categories were selected for all variables, where feasible.

Tabulation and Presentation of TB Data

This report presents descriptive results from the CTBRS, primarily for the years 2010, 2011, and 2012. Specifically, this report describes the overall number of reported active TB cases and corresponding incidence rates in Canada, by select demographic and clinical characteristics for the years 2010, 2011, and 2012 through a series of data tables (Appendix 1) and figures.^{Footnote ii},^{Footnote iii}  These characteristics include:

• reporting province/territory
• sex
• age at the time of reporting
• origin status (defined as Canadian-born Aboriginal, Canadian-born non-Aboriginal, and foreign-born)
• immigration status
• new or re-treatment case
• diagnostic classification
• bacillary status
• case detection method
• HIV status
• initial and acquired TB drug resistance
• drug regimens
• treatment outcomes

Data for active TB cases (new and re-treatment) from 2010 to 2012 were reported to the Agency between January 1, 2010 and December 31, 2013 and data for this report were extracted from the CTBRS on December 31, 2013. TB cases are counted by the date that the reporting jurisdiction confirmed the individual had TB.

Treatment outcome data are presented for the years 2009, 2010 and 2011. Outcome data received up to July 1, 2014 are included in this report.

The majority of this report focuses on cases identified in 2012, which is the most recent reporting year for which data are available. However, select data from 2010 and 2011 are also highlighted, as are important trends over time.

In this report, the term “incidence rate” refers to individuals newly diagnosed with active TB disease (new and re-treatment) in each reporting year per 100,000 population. Details on the denominators used to calculate incidence rates for Canada and various sub-populations are described in Appendix 3.

No statistical procedures were used for comparative analyses in this report, nor were any statistical techniques applied to account for missing data. Data in tables with small cell sizes (n≤5) were not suppressed, since disclosure is not deemed to pose any risk of identifying individual cases. These procedures are in line with the Agency’s directive for the collection, use, and dissemination of information relating to public health.^{Footnote 3}