Testicular volume in a cohort of prepubertal Indian children Rohith Srinivas, Reju Joseph Thomas, Tunny Sebastian, Jujju Jacob Kurian Journal of Indian Association of Pediatric Surgeons 2019 24(3):192-196 Context: There are orchidometer-based testicular volume nomograms for Indian children; however, accurate and reliable values measured by ultrasound are lacking. Aims: The aim of this study was to (1) measure the testicular volumes of boys from birth to 8 years and generate reference values and (2) to identify factors if any that may influence variation in testicular volumes. Settings and Design: This was a prospective observational study conducted on 320 children in the Department of Pediatric Surgery, Christian Medical College, Vellore, India. Subjects and Methods: A total of 320 boys without any genital abnormalities were studied. The testes were scanned using a linear transducer, and the length, width, and depth of each testis were recorded. Testicular volume was calculated using Lambert's equation – length × width × depth × 0.71. Statistical Analysis Used: Mean testicular volumes and standard deviation for every year of age were calculated. The centile values for testicular volume were computed using R software. Results: Age-specific nomogram of each testis was created separately. Interobserver variability of the measurement was shown to be up to 0.3 ml. No difference was demonstrated in the testicular volumes between the right and left testis. No correlation was found between body weight and body mass index with testicular volume. From the data on differences in size between the two sides, a volume differential index of 27% corresponds to the 95th centile. Conclusions: Reference values have been created for testicular volumes in prepubertal Indian children that could be used to assess the effects of disease and surgical interventions in this age group.