title: Evaluation of a system for grading the complexity of root canal treatment.
abstract: OBJECTIVE
  To evaluate the reproducibility of the Restorative Index of Treatment Need (RIOTN) system for grading the complexity of root canal treatment.
  
  
  METHODS
  The RIOTN system of grading the complexity of root canal treatment was applied to all endodontic referrals to a department of restorative dentistry in a district general hospital within a period of one year. Grading was repeated in 60 randomly selected teeth and weighted kappa analysis was used to test for intra-observer as well as inter-observer agreement with a consultant in restorative dentistry and a vocational trainee (VT).
  
  
  RESULTS
  In all, 152 patients were referred for root canal treatment of 186 teeth within the period of study. Weighted kappa for intra-observer agreement when categorising complexity was 0.636. Weighted kappa for inter-observer agreement with the consultant was 0.570 and that for agreement with the VT was 0.223.
  
  
  CONCLUSIONS
  The RIOTN system of grading the complexity of root canal treatment was incomplete; with moderate to poor reproducibility.
authors.affiliation: Morriston Hospital, Swansea, UK. akhila.muthukrishnan@swansea-tr.nhs.wales.uk
authors.forename: A
authors.initials: A
authors.lastname: Muthukrishnan
authors.forename: J
authors.initials: J
authors.lastname: Owens
authors.forename: S
authors.initials: S
authors.lastname: Bryant
authors.forename: P M H
authors.initials: PM
authors.lastname: Dummer
mesh_terms: D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D003788:Dental Pulp Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D003796:Dental Service, Hospital; D006301:Health Services Needs and Demand; D006801:Humans; D015588:Observer Variation; D011446:Prospective Studies; D011859:Radiography; D015203:Reproducibility of Results; D018570:Risk Assessment; D012390:Root Canal Therapy / Q000145:classification*; D012720:Severity of Illness Index; D014852:Wales