Plain radiographic evaluation of the nasopharynx: Do raters agree?

Abstract

Background Subjective plain radiographic evaluation of the nasopharynx has been a widely adopted technique. Although it has its own limitations, its ease of interpretation and simplicity are some of its advantages. Aim To investigate the reliability, using kappa, in subjectively reporting plain nasopharyngeal radiographs in children with symptoms suggestive of enlarged adenoids. Methods This was a retrospective study of the clinical records, and plain X-rays of the nasopharynx of paediatric patients with clinical features of adenoid hypertrophy in a Nigerian Tertiary Health Institution from January 2008 to December 2008. Results Fifty-one children with a mean age of 3.4 years; standard deviation of 2.772 was studied. They had an age range of 2 months to 12 years. Most (66.6%) of the children studied were in the age bracket 0–4 years. The inter-rater reliability between the two Otolaryngologists, and that between an Otolaryngologist and a Radiologist using kappa statistics were 0.6696, 95% CI (0.5035–0.8357; p < 0.05) and 0.8182, 95% CI (0.7073–0.9291; p < 0.05) respectively. While the kappa intra-rater reliabilities for the two Otolaryngologists were 0.6931, 95% CI (0.5473–0.8389) and 0.9591, 95% CI (0.9033–1.000). Conclusion There was a high level of agreement among trained raters, in subjectively interpreting plain nasopharyngeal radiographs in children with suspected adenoidal obstruction.