All that glitters isn't gold: a survey on acknowledgment of limitations in biomedical studies.

BACKGROUND: Acknowledgment of all serious limitations to research evidence is important for patient care and scientific progress. Formal research on how biomedical authors acknowledge limitations is scarce. OBJECTIVES: To assess the extent to which limitations are acknowledged in biomedical publications explicitly, and implicitly by investigating the use of phrases that express uncertainty, so-called hedges; to assess the association between industry support and the extent of hedging. DESIGN: We analyzed reporting of limitations and use of hedges in 300 biomedical publications published in 30 high and medium -ranked journals in 2007. Hedges were assessed using linguistic software that assigned weights between 1 and 5 to each expression of uncertainty. RESULTS: Twenty-seven percent of publications (81/300) did not mention any limitations, while 73% acknowledged a median of 3 (range 1-8) limitations. Five percent mentioned a limitation in the abstract. After controlling for confounders, publications on industry-supported studies used significantly fewer hedges than publications not so supported (p = 0.028). LIMITATIONS: Detection and classification of limitations was--to some extent--subjective. The weighting scheme used by the hedging detection software has subjective elements. CONCLUSIONS: Reporting of limitations in biomedical publications is probably very incomplete. Transparent reporting of limitations may protect clinicians and guideline committees against overly confident beliefs and decisions and support scientific progress through better design, conduct or analysis of new studies.

The continuity of scientific discovery and its communication: the example of Michael Faraday.

This paper documents the cognitive strategies that led to Faraday's first significant scientific discovery. For Faraday, discovery is essentially a matter seeing as, of substituting for the eye all possess the eye of analysis all scientists must develop. In the process of making his first significant discovery, Faraday learns to dismiss the magnetic attractions and repulsions he and others had observed; by means of systematic variations in his experimental set-up, he learns to see these motions as circular: it is the first indication that an electro-magnetic field exists. In communicating his discoveries, Faraday, of course, takes into consideration his various audiences' varying needs and their differences in scientific competence; but whatever his audience, Faraday learns to convey what it feels like to do science, to shift from seeing to seeing as, from sight to insight.

The brains in Brain: the coevolution of localization and its images.

Images of brain localization from Brain's inception to the present are analyzed. Textual representations and their accompanying images are shown to coevolve; that is, the technological and conceptual development of the research program of localization is shown to evolve simultaneously with the exploitation of visual resources that support these developments. The semiotics of Peirce, the social semiotics of Kress and van Leeuwen, and the insights of Gestalt psychology provide a critical vocabulary with which to describe and to analyze these visual resources. I conclude that brain images evolve in a manner that reflects the uniformity in measuring instruments and the increase in their precision in the localization of brain functions; at the same time, they draw attention away from a persistent constraint: the brain functions so precisely localized are just those that are not constitutive of our humanity.