Salmon C, et al. - In this population-based birth cohort study involving 400,611 people born in Québec, Canada, between 1970 and 1974, researchers analyzed the potential correlation of Bacillus Calmette-Guérin (BCG) vaccination and lymphoma—overall and separately for Hodgkin's (HL) and non-Hodgkin's lymphoma (NHL). In total, 178,335 individuals were BCG-vaccinated, and 1,478 cases of lymphomas were identified. Of these, 922 and 42 were determined to be NHL and HL, respectively. No connection was found among BCG vaccination and either lymphoma (any type) or NHL, following adjustment. The risk of HL was elevated amongst vaccinated people before the age of 18; however, no connection was discovered after 18 years of age. Nonproportional hazards were noted for HL. Findings suggested that BCG vaccination may increase the risk of HL before the age of 18, but residual confounding cannot be excluded in its entirety. These outcomes must, therefore, be reproduced in other populations before strong conclusions can be drawn, given the advantages of BCG vaccination, noted the authors.