Clinical Research Methodology 2: Observational Clinical Research

  title={Clinical Research Methodology 2: Observational Clinical Research},
  author={Daniel I. Sessler and Peter B. Imrey},
  journal={Anesthesia \& Analgesia},
Case-control and cohort studies are invaluable research tools and provide the strongest feasible research designs for addressing some questions. Case-control studies usually involve retrospective data collection. Cohort studies can involve retrospective, ambidirectional, or prospective data collection. Observational studies are subject to errors attributable to selection bias, confounding, measurement bias, and reverse causation—in addition to errors of chance. Confounding can be statistically… 

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  • G. Guyatt, D. Sackett, J. Keller
  • Medicine
    CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne
  • 1988
The practical approach presented in this paper allows clinicians to conduct their own N of 1 RCTs and suggests formal statistical analysis may be helpful for interpreting the results.