Epidemiologic characteristics of orthopedic surgical site infections and under-reporting estimation of registries using capture-recapture analysis

Background: Surgical Site Infections (SSIs) are among the leading causes of the postoperative complications. This study aimed at investigating the epidemiologic characteristics of orthopedic SSIs and estimating the under-reporting of registries using the capture-recapture method. Methods: This study, which was a registry-based, cross-sectional one, was conducted in six educational hospitals in Tehran during a one-year period, from March, 2017 to March, 2018. The data were collected from two hospital registries (National Nosocomial Infection Surveillance System (NNIS) and Health Information Management database (HIM)). First, all orthopedic SSIs registered in these sources were used to perform capture-recapture (N = 503). Second, 202 samples were randomly selected to assess patients` characteristics. Results: Totally, 76.24 of SSIs were detected post-discharge. Staphylococcus aureus (11.38) was the most frequently detected bacterium in orthopedic SSIs. The median time between the detection of a SSI and the discharge was 17 days. The results of a study done on 503 SSIs showed that the coverage of NNIS and HIM was 59.95 and 65.17, respectively. After capture-recapture estimation, it was found that about 221 of orthopedic SSIs were not detected by two sources among six hospitals and the real number of SSIs were estimated to be 623 ± 36.58 (95 CI, 552�695) and under-reporting percentage was 63.32. Conclusion: To recognize the trends of SSIs mortality and morbidity in national level, it is significant to have access to a registry with minimum underestimated data. Therefore, according to the weak coverage of NNIS and HIM among Iranian hospitals, a plan for promoting the national Infection Prevention and Control (IPC) programs and providing updated protocols is recommended. © 2021, The Author(s)

Evaluation of physiology knowledge loss in medical students of Ahvaz Jundishapur University of Medical Sciences

Narjes Zaeemzadeh,1 Sanaz Taherpour,2 Noor Behzadian,2 Seyyed Ali Mard2 1Deparment of Phamacology, The School of Pharmacy, Medical Educational and Development Center (EDC), Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 2Physiology Research Center (PRC), Department of Physiology, School of Medicine, Medical Educational and Development Center (EDC), Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Purpose: The knowledge loss or longevity of taught lessons is a major concern in medical students and all medical practitioners. This study evaluated the physiology knowledge loss in medical students in Ahvaz Jundishapur University of Medical Sciences in Iran. Methods: A total of 265 volunteers from medical students who had previously passed the “general exam of medical basic sciences” at the end of fifth semester took a retention test (RT) to evaluate their knowledge loss of physiology. The candidates were divided into ten groups depending on the semester (S) they were passing at the time of study: 41 students in preclinical levels (S6 and S7), 123 students in externship levels (S8, S9, S10, S11 and S12), and 101 students in internship levels (S13, S14 and S15). The RT consisted of 20 multiple choice questions from all topics of medical physiology, including central nervous system, endocrine, gastrointestinal, cardiovascular, respiratory, renal, blood, and cellular. Results: Findings showed that there was a decreasing trend of knowledge loss from S6 to S15. The lowest level of knowledge loss was observed in S15 students. These results also demonstrated that knowledge loss in male medical students was more than that in female students. Conclusion: These findings indicated that the physiology knowledge loss trend is inversely correlated with the time passing. We conclude that the reason is that physiology is a basic science which is most applicable during medical students’ clinical years. Keywords: Ahvaz, Iran, medical students, physiology, knowledge loss, retention test, female studen

Estimation of the basic reproduction number (R0) of the COVID-19 epidemic in Iran

Background: Estimation of the basic reproduction number of an infectious disease is an important issue for controlling the infection. Here, we aimed to estimate the basic reproduction number (R0) of COVID-19 in Iran. Methods: To estimate R0 in Iran and Tehran, the capital, we used 3 different methods: exponential growth rate, maximum likelihood, and Bayesian time-dependent. Daily number of confirmed cases and serial intervals with a mean of 4.27 days and a standard deviation of 3.44 days with gamma distribution were used. Sensitivity analysis was performed to show the importance of generation time in estimating R0. Results: The epidemic was in its exponential growth 11 days after the beginning of the epidemic (Feb 19, 2020) with doubling time of 1.74 (CI: 1.58-1.93) days in Iran and 1.83 (CI: 1.39-2.71) in Tehran. Nationwide, the value of R0 from February 19 to 29 using exponential growth method, maximum likelihood, and Bayesian time-dependent methods was 4.70 (95 CI: 4.23�5.23), 3.90 (95 CI: 3.47�4.36), and 3.23 (95 CI: 2.94�3.51), respectively. In addition, in Tehran, R0 was 5.14 (95 CI: 4.15�6.37), 4.20 (95 CI: 3.38�5.14), and 3.94 (95 CI: 3.45�4.40) for exponential growth, maximum likelihood, and Bayesian time-dependent methods, respectively. Bayesian time dependent methods usually provide less biased estimates. The results of sensitivity analyses demonstrated that changes in the mean generation time affect estimates of R0. Conclusion: The estimate of R0 for the COVID-19 ranged from 3.94 to 5.14 in Tehran and from 3.23 to 4.70 in nationwide using different methods, which were significantly larger than 1, indicating the potential of COVID-19 to cause an outbreak. This work has been published under CC BY-NC-SA 1.0 license. Copyright © 2020. Iran University of Medical Sciences