Validation of Recorded Diagnosis in Patients Registered in the Iranian Registry of Crohn’s and Colitis

Abstract

Background:

The Iranian Registry of Crohn's and Colitis (IRCC) operates in collaboration with physicians from across Iran. To ensure the usability of this database for future studies, it is necessary to validate the diagnoses recorded in this registry.

Materials and Methods:

 From the list of IRCC patients, a total of 100 patients from 10 physicians were randomly selected. The contact information of these patients was sent to their respective physicians, and they were requested to send the clinical and laboratory documents of their 10 selected patients. These documents were then reviewed by two other gastroenterologists. The recorded diagnoses were compared with the adjudicated diagnoses using the kappa method. Additionally, the accuracy of the recorded diagnosis was assessed by calculating the positive predictive value (PPV) with a 95% confidence interval (CI) and plotting the ROC curve. A P value < 0.05 was considered statistically significant.

Results:

Information for 96 patients was available. Data for 27 patients were incomplete and thus excluded from the study. Of the remaining 69 patients, 51 (73.9%) had ulcerative colitis, 28 (40.6%) were female, and the mean age was 43.9 with a standard deviation of 14. After reviewing the patients’ documents, the two physicians' diagnoses were compared, and a final diagnosis was recorded. The adjudicated diagnoses were compared with the initial patient diagnosis, yielding a kappa of 0.81 and 92% agreement. The PPV of the diagnosis recorded in IRCC was calculated as 97.9% (95% CI = 94.4-104.4%). Furthermore, the ROC curve had an area under the curve (AUC) of 0.94.

Conclusion:

The diagnosis recorded in the Iranian Registry of Crohn's and Colitis (IRCC) is highly accurate and reliable for use in future studies.