Inter-observer reliability of radiological signs of necrotising enterocolitis in a population of high-risk newborns

Summary Radiological examination of the abdomen is critical to the diagnosis of necrotising enterocolitis (NEC). Previous studies on the reproducibility of radiological findings have been limited in size and based only on infants with the disease. We conducted a study among a sample of high-risk infants with and without the diagnosis of NEC: (1) to measure the degree of inter-observer agreement of NEC radiological diagnosis and signs and (2) identify a profile of radiological signs which led the observers to make a diagnosis of NEC. We collected 297 X-rays from a sample of 57 newborns admitted in 1999 to neonatal intensive care and neonatal surgery units in Rome, Italy. Three specialists in paediatric radiology examined the films independently and without any clinical information about patients. The analyses were conducted on a total of 891 forms filled in by the observers. Kappa values were calculated to measure the inter-observer reliability. To identify the profiles of radiological signs, a multidimensional analysis, binary segmentation, was carried out. The reproducibility of radiographic signs was 0.55 (P