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Part 1

A study was conducted by Ferguson and Simes using all Indian infants born in the Qu'Appelle Indian Health Unit in southern Saskatchewan during the period October 1933 to December 1945. Families of comparable social and economic status were paired and randomly allocated to one of two groups labelled A and B. All children born into families in group A were vaccinated with BCG vaccine in a given year and those born into families B were used as controls. In the following year the situation was reversed and this scheme was followed throughout the years of the study. Over a period of years there were 306 children in the vaccinated group and 303 in the unvaccinated group.

The data from their original study (Tubercle 30: 5-11, 1949) has been re-fashioned in the Table below:

Tuberculosis cases Vaccinated Not Vaccinated
YES 6 29
NO 297 274

The data includes information gathered up to August 1947

Thus the relative risk of non-vaccinated infants getting TB was 4.88.

Part 2

Half-a century later, Maureen Lux (CBMH Vol. 15, 1998, p. 277-295) looked at the Qu’Appelle BCG Vaccine trial from the perspective of the subjects themselves. She asked "How did an isolated, poverty-stricken agency in an equally isolated province come to be the site for a major medical experiment? Who were the subjects and how did they benefit?"

The last sentence read "The BCG trial was a success, but unfortunately the patients died."


Historical cases provide an opportunity for students to reflect on changes in knowledge and attitudes. Using this problem, the students explored the biological aspects of tuberculosis, the routes of infection and pathological changes. They also delved into the social and economic context of the Qu’appelle trial and also considered the design of clinical trials in general.

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