Like all epidemiologic studies, the Danish study is not perfect, but its strengths should also be acknowledged.

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Appliance usage may be a main effect variable in epidemiologic studies of health impacts of electromagnetic fields.

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Yet epidemiologic studies tell us that one in four persons will suffer from mental illness in their lifetime.

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In three epidemiologic studies on workers exposed to 1, 4-dioxane, the observed number of cancer cases did not differ from the expected cancer deaths.

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Certain epidemiologic studies (mainly from a single group in Sweden) indicate an elevated risk of glioma (the most malignant type of brain cancer) in long-term users of cell phones.

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Furberg has co-authored epidemiologic studies that showed problems for Bextra, and he was the harshest Pfizer critic on the panel--at one point saying inconsistencies in the company's data submissions smacked of dishonesty.

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Many of these reports are based on the results of epidemiologic studies, which examine associations between a wide range of behaviors and exposures, on the one hand, and the development of diseases, on the other.

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Epidemiologic studies over the past 40 years have identified numerous risk factors for breast cancer, including: older age, an early age at menarche, a late age at first full-term birth, not having children, a family history of breast cancer in a first-degree relative, greater height, higher circulating estrogen levels, postmenopausal hormone use, breast density, history of breast biopsies, obesity (for postmenopausal breast cancer), and exposure to ionizing radiation.

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