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S Brorson

Publications and source records attributed to S Brorson.

5 recordsLinked to original sources
PubMed2002

Low agreement among 24 doctors using the Neer-classification; only moderate agreement on displacement, even between specialists.

Twenty-four orthopaedic surgeons classified 42 pairs of radiographs according to the Neer system for proximal humeral fractures. Mean kappa value for inter-observer agreement was 0.27 (95% CI 0.26-0.28) with no clinically significant difference between orthopaedic residents ( n=9), fellows ( n=6) and specialists ( n=9). Mean kappa for agreement of displacement versus non-displacement was 0.41 (95% CI 0.39-0.43) overall, and 0.50 (95% CI 0.45-0.56) within the specialist group. The agreement found in our study is unsatisfactory from a clinical perspective.

Confidence Intervals↗
PubMed2002

Improved interobserver variation after training of doctors in the Neer system. A randomised trial.

We investigated whether training doctors to classify proximal fractures of the humerus according to the Neer system could improve interobserver agreement. Fourteen doctors were randomised to two training sessions, or to no training, and asked to categorise 42 unselected pairs of plain radiographs of fractures of the proximal humerus according to the Neer system. The mean kappa difference between the training and control groups was 0.30 (95% CI 0.10 to 0.50, p = 0.006). In the training group the mean kappa value for interobserver variation improved from 0.27 (95% CI 0.24 to 0.31) to 0.62 (95% CI 0.57 to 0.67). The improvement was particularly notable for specialists in whom kappa increased from 0.30 (95% CI 0.23 to 0.37) to 0.79 (95% CI 0.70 to 0.88). These results suggest that formal training in the Neer system is a prerequisite for its use in clinical practice and research.

Clinical Competence↗
PubMed2000

Ludwik Fleck on proto-ideas in medicine.

'Proto-idea' was a central concept in the thinking of the Polish microbiologist and philosopher of science Ludwik Fleck (1896-1961). Based on studies of the origin of the modern concept of syphilis, Fleck claimed that many established scientific facts are best understood as interpretations of prescientific, somewhat hazy 'proto-ideas' in the framework of a certain 'thought-style'. As an example, Fleck saw the modern knowledge of infection as an interpretation of the ancient proto-idea of diseases as caused by minute 'animalcules'. However, the epistemological aspects of the concept of proto-ideas have only been sparsely developed and discussed by Fleck and his critics. This paper attempts to bridge the gap. Firstly, I reconstruct the concept of proto-ideas in the context of Fleck's constructivist theory of knowledge. Secondly, I illustrate the relation between Fleck's concept of proto-ideas and his nominalist view on medical taxonomy. Finally, I discuss four philosophical problems implied by Fleck's concept of proto-ideas: (a) the problem of combining two conflicting perspectives on the history of science (b) the problem of accounting for the notion of 'continuity' within a nonrealist theory of knowledge (c) the problem of ascribing no truth-content to proto-ideas, and (d) the problem concerning the non-neutrality of the analyst's viewpoint.

Classification↗
PubMed1991

Comparative studies of femtosecond to microsecond laser pulses on selective pigmented cell injury in skin.

Threshold radiant exposures for grossly apparent immediate whitening and ultrastructural alterations of melanosomes in black guinea pig skin were determined for a series of red visible laser pulses ranging from 4 x 10(-4) to 6.5 x 10(-14) s. Threshold exposures for melanosomal injury were found to be independent of pulsewidth when the pulsewidths were below the estimated thermal relaxation time of melanosomes. Threshold radiant exposures for melanosomal injury were found to increase when the pulsewidths were approximately equal to or above the thermal relaxation time of melanosomes. At longer pulse durations, fracturing of melanosomes was not observed despite the longer exposures necessary for injury. Instead, perimelanosomal vacuoles were noted. These findings are consistent with the theory of selective photothermolysis and provide evidence for the thermal initiation of melanosomal disruption.

Animals↗