Formulation and validation of meatal stenosis grading system

Abstract

Meatal stenosis (MS) is a common finding in circumcised children. Indication for surgical correction is based on urinary symptoms such as strength and direction of urine stream as well as physical examination, including direction and caliber of the urinary stream. There is no objective grading of MS severity, and therefore indications for surgery and management protocols are vague. We aimed to formulate a standardized, validated, and reliable grading system for MS severity based on the physical examination finding. Photographs of the urethral meatus were taken in patients scheduled for meatotomy due to MS, whereas patients without this condition served as control. The photographs were rated by three experienced fellowship trained pediatric urologists. The study was conducted in two phases: 1) development of a grading system by the expert panel and 2) testing of the proposed grading system for inter- and intra-rater reliability. To estimate the correlation between different rates, the intra-class correlation coefficient (ICC) was calculated. Three grades were generated: Grade 0 (wide open meatus, visible mucosa), Grade 1 (minimal mucosa/fibrotic tissue visible), and Grade 2 (pinpoint meatus/no mucosa visible/large fibrotic layer). A panel of 51 raters (pediatric urologist, community urologist, pediatricians) participated in the survey evaluating the representative photos from 86 patients. Inter-rater reliability was high ICC=0.99 (95% confidence interval [CI] of 0.983-0.996, P<0.0001) Cronbach's alpha=0.992. In total, 18 raters participated in the same survey two weeks later for intra-rater reliability. An identical grading was obtained in 83.3% of photographs (kappa=0.455 [P<0.05]). We propose a grading system that is a valid, reliable, and reproducible method to classify the severity of MS on physical exam. This grading system could improve the healthcare provider's and parent's communication and can be a building block for further research in this field. A further research should assess the correlation with clinical signs and symptoms.