Characteristics of the studies related to the effects of GSTs genetic polymorphisms and lung cancer risk.

<p>Pathologic diagnosis^¶: ALL means that all lung cancer cases were confirmed by pathologic diagnosis; PARTIAL means that partial cases were confirmed by pathologic diagnosis; NA means that relative data were not available in original studies.</p><p>SC: Squamous Carcinoma; AC: Adenocarcinoma; SCLC: Small Cell Lung Carcinoma; NSCLC: Non-small-cell Lung Carcinoma. *: Articles published in English.</p><p>: These data were omitted because of a larger sample from the same studied population by the same research group.</p><p>a/b: A study with two distinct controls encompassed population-based and hospital-based could been analyzed, respectively.