Dear Editor: I read with interest your paper entitled “Pre and post-test probabilities and Fagan’s NOMOGRAM”. I would like to add a note concerning an update on Fagan’s NOMOGRAM. Generally, the basic idea of most NOMOGRAMs is having the scales of 3 variables in a manner that if you draw a straight line between 2 values, the 3rd value is found where the line intersects the 3rd scale. They were initially developed in the 1980s by Maurice D’Ocange.

Introduction and aim: Hypertesion is one of the major disorders in medicine. In several investigations in Iran the NOMOGRAMs of children blood pressure were different with American standard NOMOGRAMs. The aim of this study was to prepare the NOMOGRAMs of children blood pressure in Birjand primary schools students.Methods: 1928 students were selected by a systemic and cluster sampling. Standard blood pressure measurements were done for each student.Results: In all groups' except 7 years student there was a positive correlation between age and the level of systolic and diastolic blood pressure. The mean of diastolic blood pressure in both sexes and all ages were meaningfully more than the standard and the mean of systolic blood pressure was higher than the standard only in 7 years. The prevalence of hypertention was 8.7% and 7.1% in girls and boys respectively (P<0.05).Conclusion: According to the existing difference between the normal blood pressure in the Birjand and the standard NOMOGRAM, Iranian NOMOGRAM shoul be developed for evaluation of blood pressure.

Background: Hyperbilirubinemia is one of the most common causes of neonatal re-hospitalization; using transcutaneous bilirubin (TCB) measurement NOMOGRAM, the aim of this study was to determine the risk of severe hyperbilirobinemia in term and near-term Iranian neonates at discharge time.Methods: 450 healthy newborn infants, with the gestational age of ≥35 weeks, weight of ≥2 kg, and the age of 12 to 140 hours were enrolled in this randomized-descriptive practical study. Before being discharged, the infant’s bilirubin was measured using Bilichek that was placed on their chest and between two nipples. After being discharged, the newborn infants were followed up. According to the discharge time transcutaneous bilirubin level, the infant's age (in terms of hour), and based on bilirubin NOMOGRAM, the newborns were divided into four groups of low-risk, low-medium-risk, high-medium-risk, and high-risk. In following up the infants, if they were suffering hyperbilirobinemia, the bilirubin was measured again.Findings: According to discharge time transcutaneous bilirubin level and the infant's based-on-hour age, 20% of the subjects were included in the low-risk group, 33.1% in low-medium-risk group, 32.2% in high-medium-risk group, and 14.7% in high-risk group. The risk of severe hyperbilirobinemia in followed-up newborns was 1.4%, 6.9%, 13.6%, and 32.8%, in groups 1 to 4, respectively. During this time, 11.9% of the newborns were found to have sever hyperbilirubinemia (more than 95th percentile.Conclusion: By providing bilirubin NOMOGRAM, based on transcutaneous bilirubin level and the infant's age (in terms of hour), the severity of future hyperbilirobinemia can be estimated in Iranian healthy newborns. The transcutaneous bilirubin method with bilichek, that is a non-invasive method, can be recommended for all newborns at discharge time.

Background: Comparing and determining the accuracy of -urolo gists and STONE NOMOGRAM prediction about the Percutaneous Nephrolithotomy (PCNL) outcomes in urolithiasis patients.Methods: This retrospective cohort study was performed on 70 patients who underwent PCNL in Firoozgar Hospital (Tehran, Iran) from March 2019 to April 2020. Two expert urologists, who were not informed about the actual result of the procedure and did not have access to the post-operative data, were asked to predict the success rate of PCNL based on pre-operative imaging. The remaining stone size of less than 4 mm was considered as stone-free in PCNL. On the other hand, the STONE NOMOGRAM calculated the stone-free rate, and if the predicted success rate was over 60%, PCNL was considered successful based on the STONE NOMOGRAM. Results: The accuracy of the urologist’s prediction was 76.42%. The STONE NOMOGRAM correctly predicted the PCNL result in 59 cases (84.28%). There was a significant correlation between the actual success rate of the PCNL and the NOMOGRAM’s prediction (p-value= 1.013×10-5). There was no significant difference between the surgeons and the NOMOGRAM’s prediction (p-value=0.336). The number of stones did not significantly affect the correct prediction of surgical results (p-value<0.05). Upper calyx stones caused a significant difference between correct prediction of surgical results by surgeons and NOMOGRAMs (p-value<0.05).Conclusion: No significant difference was found between surgeons’ prediction and STONE NOMOGRAM, but only in patients with kidney stones in the upper calyx; the NOMOGRAM’s prediction accuracy was higher.