ets exposure, lung cancer - Legacy Tobacco Documents Library

• Despite the study's use of cotinine to assess current tobacco
use, the authors acknowledge that misclassification of ever
smokers as lifetime never smokers is "problematic" because
there is "no biomarker of lifetime tobacco use ." Moreover,
only slightly more than half (54%) of cases had cotinine
determinations . Thus, not even recent active smoking was
excluded for nearly half of the cases .
• While the authors stress that their study is a multicenter
case-control study, if the characteristics of the study
population are examined, it is seen that the vast majority of
cases and controls come from two areas in California (Los
Angeles and the San Francisco Bay area) . Yet, the authors do
not indicate that air pollution, which has been suggested to
be a lung cancer risk factor, was "adjusted" for in their
analyses . In fact, the authors provide no breakdown of the
data by study center, and it is not possible to ascertain
whether the reported risks were consistent across the centers .
Heterogeneity in the data among study sites would argue
against combining the data as was done in this paper .
• Among other potential confounders that were not considered in N
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the analyses is dietary saturated fat intake, recently N
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reported by Alavanja, et al ., to be associated with relative ~
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risks as high as 6 .0 to 11 .0 . The risk was highest in ¢,
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nonsmoking women with adenocarcinoma ; over 75% of the cases in n
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http://legacy.library.ucsf.edu/tid/wyk81f00/pdf