In the article on aldehyde dehydrogenase 2 and head and neck cancer in the January 2009 issue (1), two errors should be noted.

In Table 1, page 250: the Confidence Interval (CI) of the study of Hiraki at al. (0.39– 1.03) is incorrect. Even though the point estimate is correct (0.76), the right CI is the one reported in Figure 1, page 251, namely (0.43–1.34).

In the Results section, page 251, left column, ninth line from the bottom: the OR among never-drinkers is incorrect (OR=1.03; 0.69–1.55). The correct OR is that of Figure 2 (OR=0.97; 95%CI: 0.65–1.46).

Boccia S, Hashibe M, Galli P, et al. Aldehyde dehydrogenase 2 and head and neck cancer: A meta-analysis implementing a Mendelian randomization approach.
Cancer Epidemiol Biomarkers Prev