|Although tobacco smoking has been shown to be significantly associated with many CRDs, evidence linking secondhand tobacco smoke exposure to different CRDs is inconsistent, especially with low levels of SHS exposure. Research on the health effects of SHS exposure pose a particular challenge due to the tools used to measure SHS exposure. For example, it has been shown that self-report of SHS exposure can be inaccurate, frequently underestimating SHS exposure. One type of measurement tool designed to increase the accuracy of a subjectÃ¢â¬â¢s SHS exposure, particularly at low levels of SHS exposure, are biomarkers of tobacco smoke exposure. Thus, robust studies investigating associations between SHS exposure and CRDs frequently include both self-report as well as objective biomarker measurements to verify or quantify such exposures. The two most recent incarnations of the NHANES series, the NHANES III and the continuous NHANES, include serum biomarker data of tobacco smoke exposure which create both significant advantages as well as complications for research using data from this study. We review both NHANES studies regarding survey design and data available. John D. Clark III, Utilization of the National Health and Nutrition Examination (NHANES) Survey for Symptoms, Tests, and Diagnosis of Chronic Respiratory Diseases and Assessment of Second hand Smoke Exposure.
High-impact journals are those considered to be highly influential in their respective fields. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.