Children’s Hospital of Philadelphia score to predict Type 1 retinopathy of prematurity in a resource-limited country

Background: Retinopathy of prematurity (ROP) leads to permanent vision loss unless treated timely. National screening guidelines for ROP are sensitive but lack specificity. The Children’s Hospital of Philadelphia ROP (CHOP ROP) model is highly specific for detecting severe ROP. Aim: The aim of the study was to evaluate the diagnostic performance of the CHOP ROP model in an Indian setting. Setting: In this prospective observational study, preterm neonates admitted to the neonatal intensive care unit were included. Materials and Methods: The screening was done as per the conventional screening guidelines. The CHOP ROP algorithm was applied to all neonates undergoing ROP screening, and the risk score was calculated from 2 nd week onward. Statistics: The sensitivity, specificity, and Pearson coefficient of the CHOP algorithm in detecting Type 1 ROP were calculated. Results: Keeping the alarm level at 0.014, 143 (87.2%) babies fall into the low-risk group and 21 (12.8%) in the high-risk group. The sensitivity and specificity of the CHOP algorithm in detecting Type 1 ROP were 33% and 88%, respectively. Keeping the alarm level at 0.001, 118 (72%) babies were categorized as high risk, including 8 Type 1 ROP. Conclusion: The CHOP ROP model is unsuitable as an adjunct to the conventional screening guidelines to reduce the screening burden. This may be because the original nomogram was developed based on the screening criteria of Western countries. In India, where larger and older preterm babies tend to develop ROP, the nomogram may need to be updated.