BIAS & CONFOUNDING M . Tevfik DORAK
نویسنده
چکیده
Introduction In epidemiologic research, it is essential to avoid bias, to control confounding and to undertake accurate replication. Bias, confounding and random variation/chance are the non-causal reasons for an association between an exposure and outcome. These major threats to internal validity of a study should always be considered as alternative explanations in the interpretation. Bias is a mistake of the researcher; confounding is not a mistake and when obvious, it can be controlled; replication is up to the researcher.
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