Incidence of Beijing and Non-Beijing strains of M. tuberculosis in Alberta, 1991–2007.

Abbreviations: PYRs, person-years of observation; RR, incidence rate ratio; CI, confidence interval; CB, Canadian-born; FB, foreign-born; WP, Western Pacific.*Estimates of the foreign-born and Canadian-born populations were derived from customized Statistics Canada census reports. Estimates for Canadian-born ‘other’ were those derived from the censuses minus the annual population of Canadian-born Aboriginal peoples as obtained directly from Indian and Northern Affairs Canada.†Crude incidence rate per 100,000 person-years.