Overt and Hidden Bias in Large Observational Studies
نویسندگان
چکیده
منابع مشابه
Avoiding Bias in Observational Studies
T he randomized clinical trial is a well established and frequently used study design and is generally accepted as the gold standard (1). Nevertheless, many questions can only be answered with epidemiological observational studies, such as the influence of cigarette consumption on the development of lung cancer (2), the effects of sport, nutrition and overweight on cardiovascular diseases (3), ...
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In observational studies subjects are not randomly assigned to treatment and control groups. Therefore, both groups can be significantly different from each other and their differences after applying a treatment cannot be attributed to the treatment effect. Propensity scores methods offer a way to balance groups by matching treatment and control units based on a set of covariates. This paper ex...
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Commentary I nstrumental variable analysis is an increasingly popular statistical method in epidemio-logic research. 1 epidemiologists' enthusiasm for this approach may be because it can potentially estimate causal effects in observational data in the presence of unmeasured confounding. 2 This overcomes a significant limitation of conventional epidemiologic methods, such as multivariable regres...
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ژورنال
عنوان ژورنال: American Journal of Psychiatry
سال: 2016
ISSN: 0002-953X,1535-7228
DOI: 10.1176/appi.ajp.2016.16050579