BACKGROUND: As an observational science, epidemiology is regarded by
some researchers as inherently flawed and open to false results. In a
recent paper, Boffetta et al. [Boffetta P, McLaughlin JK, LaVecchia C,
Tarone RE, Lipworth L, Blot WJ. False-positive results in cancer
epidemiology: a plea for epistemological modesty. J Natl Cancer Inst
100:988-995 (2008)] argued that “epidemiology is particularly prone to
the generation of false-positive results.” They also said “the
tendency to emphasize and over-interpret what appear to be new findings
is commonplace, perhaps in part because of a belief that the findings
provide information that may ultimately improve public health” and
that “this tendency to hype new findings increases the likelihood of
downplaying inconsistencies within the data or any lack of concordance
with other sources of evidence.” The authors supported these serious
charges against epidemiology and epidemiologists with few examples.
Although we acknowledge that false positives do occur, we view the
position of Boffetta and colleagues on false positives as unbalanced and
potentially harmful to public health.
OBJECTIVE: We aim to provide a more balanced evaluation of epidemiology
and its contribution to public health discourse.
DISCUSSION: Boffetta and colleagues ignore the fact that false negatives
may arise from the very processes that they tout as generating
false-positive results. We further disagree with their proposition that
false-positive results from a single study will lead to faulty decision
making in matters of public health importance. In practice, such public
health evaluations are based on all the data available from all relevant
disciplines and never to our knowledge on a single study.
CONCLUSIONS: The lack of balance by Boffetta and colleagues in their
evaluation of die impact of false-positive findings on epidemiology, the
charge that “methodological vigilance is often absent” in
epidemiologists’ interpretation of their own results, and the false
characterization of how epidemiologic findings are used in societal
decision making all undermine a major source of information regarding
disease risks. We reaffirm the importance of epidemiologic evidence as a
critical component of the foundation of public health protection