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Science as experiment; science as observation

Nature Clinical Practice Rheumatology volume 2, pages 286–287 (2006)Cite this article

Randomized, blinded, controlled experiments are often considered the highest level of evidence in the methodologic hierarchy. Advocates of observational studies claim that rigorously performed nonrandomized studies can contribute to the understanding of disease and its management equally as well as randomized, controlled trials (RCTs) can, but many advocates of CLINICAL TRIALS (as well as of the tenets of EVIDENCE-BASED MEDICINE) disagree. Understanding the strengths and limitations inherent to each study design will enable consumers of medical literature to best utilize the data presented.

RCTs address critically important biases of nonrandom assignment and unblinded observation with excellent internal validity, but they are limited by short periods of observation, relatively small sample sizes, the narrow generalizability of results, an inability to address many important patient-oriented questions, and a lack of desirable comparator groups. Just as RCTs have contributed essential information about biological activity and short-term therapeutic efficacy and toxicity, well-performed, protocol-driven observational studies have led to a greater understanding of the natural history and impact of therapy on the rheumatic diseases, particularly in rheumatoid arthritis (RA).

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Authors and Affiliations

  1. Professor of Medicine,

    Eliza F Chakravarty & James F Fries

  2. Assistant Professor of Medicine in the Division of Immunology and Rheumatology at Stanford University, CA, USA

    Eliza F Chakravarty & James F Fries

Authors
  1. Eliza F Chakravarty
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  2. James F Fries
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Correspondence to James F Fries.

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The authors declare no competing financial interests.

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Chakravarty, E., Fries, J. Science as experiment; science as observation. Nat Rev Rheumatol 2, 286–287 (2006). https://doi.org/10.1038/ncprheum0192

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