Till sidans topp

Sidansvarig: Webbredaktion
Sidan uppdaterades: 2012-09-11 15:12

Tipsa en vän
Utskriftsversion

A method to analyse obser… - Göteborgs universitet Till startsida
Webbkarta
Till innehåll Läs mer om hur kakor används på gu.se

A method to analyse observer disagreement in visual grading studies: example of assessed image quality in paediatric cerebral multidetector CT images.

Artikel i vetenskaplig tidskrift
Författare Kerstin Ledenius
E Svensson
F Stålhammar
Lars-Martin Wiklund
Anne Thilander-Klang
Publicerad i The British journal of radiology
Volym 83
Nummer/häfte 991
Sidor 604-11
ISSN 1748-880X
Publiceringsår 2010
Publicerad vid Institutionen för kliniska vetenskaper, Avdelningen för radiofysik
Institutionen för kliniska vetenskaper, Avdelningen för pediatrik
Sidor 604-11
Språk en
Länkar dx.doi.org/10.1259/bjr/26723788
Ämnesord Adolescent, Brain, radiography, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Neurology, Observer Variation, Pediatrics, Reproducibility of Results, Retrospective Studies, Statistics, Nonparametric, Tomography, X-Ray Computed, methods, statistics & numerical data
Ämneskategorier Diagnostisk radiologi, Radiofysik

Sammanfattning

The purpose was to demonstrate a non-parametric statistical method that can identify and explain the components of observer disagreement in terms of systematic disagreement as well as additional individual variability, in visual grading studies. As an example, the method was applied to a study where the effect of reduced tube current on diagnostic image quality in paediatric cerebral multidetector CT (MDCT) images was investigated. Quantum noise, representing dose reductions equivalent to steps of 20 mA, was artificially added to the raw data of 25 retrospectively selected paediatric cerebral MDCT examinations. Three radiologists, blindly and randomly, assessed the resulting images from two different levels of the brain with regard to the reproduction of high- and low-contrast structures and overall image quality. Images from three patients were assessed twice for the analysis of intra-observer disagreement. The intra-observer disagreement in test-retest assessments could mainly be explained by a systematic change towards lower image quality the second time the image was reviewed. The inter-observer comparisons showed that the paediatric radiologist was more critical of the overall image quality, while the neuroradiologists were more critical of the reproduction of the basal ganglia. Differences between the radiologists regarding the extent to which they used the whole classification scale were also found. The statistical method used was able to identify and separately measure a presence of bias apart from additional individual variability within and between the radiologists which is, at the time of writing, not attainable by any other statistical approach suitable for paired, ordinal data.

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11
Dela:

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?