title: Making the grade? Modification of dental radiograph quality ratings.
abstract: OBJECTIVE
  To compare the intra- and inter-assessor agreement and operator preference of a modified (four-grade) quality rating system for dental radiographs with the current National Radiological Protection Board (NRPB) (three-grade) quality rating system.
  
  
  METHODS
  Sixty radiographic images of varying quality were selected by retrospective review of dental records from a general dental practice. The images were sorted into groups to represent examples of radiographic quality (1=excellent, 2=diagnostically acceptable, 3=diagnostically compromised, 4=unacceptable). A 'gold standard' for radiological quality assessment was provided by a consultant in dental and maxillofacial radiology. A compact disc (CD) of the 60 images was produced and posted to a panel of 14 general dental practitioners (GDPs) who were asked to grade the quality of the images using two different systems on two occasions separated by a washout period of two days. The practitioners graded the radiographs using the currently accepted method for assessing radiographic quality (the three-grade NRPB system) and the alternative four-grade system. The quality of the images on the CD was deemed appropriate by the consultant.
  
  
  RESULTS
  The strength of inter-assessor agreement was weaker when using a four-grade system in comparison to a three-grade system, reducing to a mean of k=0.51 from a mean of k=0.61 when using the original grading system. Mean agreement did not fall below 'moderate agreement' (k=0.41-0.60). Eleven of the 14 GDPs preferred the four-grade system.
  
  
  CONCLUSIONS
  The GDPs who participated in this study preferred the four-grade system to the three-grade system when comparing the quality of dental radiographs. However, the strength of agreement was weaker when using the four-grade system in comparison to the three-grade system. Overall, the results are equivocal. However, they should help to inform specialist dental radiology panels, should revision of quality grading be undertaken in the future.
authors: National Institute for Health Research Academic Clinical Fellowship (Orthodontics), Oral Health Unit, School of Dentistry, University of Manchester, UK.
authors: George D
authors: GD
authors: Rodgers
authors: Mohammad O
authors: MO
authors: Sharif
authors: Adam B
authors: AB
authors: Smith
authors: Margaret
authors: M
authors: Kellett
authors: Paul A
authors: PA
authors: Brunton
mesh_terms: D004739:England; D005792:General Practice, Dental; D006801:Humans; D015588:Observer Variation; D019984:Quality Indicators, Health Care; D011861:Radiography, Dental / Q000592:standards*; D011795:Surveys and Questionnaires