OBJECTIVES: Kidney transplantation is the best renal replacement therapy for patients with end-stage renal disease. Several studies have attempted to identify predisposing factors of graft rejection; however, the results have been inconsistent. We aimed to identify prognostic factors associated with kidney transplant rejection using the artificial neural network (ANN) approach and to compare the results with those obtained by logistic regression (LR). METHODS: The study used information regarding 378 patients who had undergone kidney transplantation from a retrospective study conducted in Hamadan, Western Iran, from 1994 to 2011. ANN was used to identify potential important risk factors for chronic nonreversible graft rejection. RESULTS: Recipients' age, creatinine level, cold ischemic time, and hemoglobin level at discharge were identified as the most important prognostic factors by ANN. The ANN model showed higher total accuracy (0.75 vs. 0.55 for LR), and the area under the ROC curve (0.88 vs. 0.75 for LR) was better than that obtained with LR. CONCLUSIONS: The results of this study indicate that the ANN model outperformed LR in the prediction of kidney transplantation failure. Therefore, this approach is a promising classifier for predicting graft failure to improve patients' survival and quality of life, and it should be further investigated for the prediction of other clinical outcomes.
Causality ; Cold Ischemia ; Creatinine ; Data Mining ; Graft Rejection* ; Humans ; Iran ; Kidney Failure, Chronic ; Kidney Transplantation ; Kidney* ; Logistic Models ; Quality of Life ; Renal Replacement Therapy ; Retrospective Studies ; Risk Factors ; ROC Curve ; Transplants*

STUDY DESIGN: A cross-sectional, descriptive study. PURPOSE: This study aimed to investigate the relationship between kyphosis and lordosis measured by using a flexible ruler and musculoskeletal pain in students of Hamadan University of Medical Sciences. OVERVIEW OF LITERATURE: The spine supports the body during different activities by maintaining appropriate body alignment and posture. Normal alignment of the spine depends on its structural, muscular, bony, and articular performance. METHODS: Two hundred forty-one students participated in this study. A single examiner evaluated the angles of lumbar lordosis and thoracic kyphosis by using a flexible ruler. To determine the severity and frequency of pain in low-back and inter-scapular regions, a tailor-made questionnaire with visual analog scale was used. Finally, using the Kendall correlation coefficient, the data were statistically analyzed. RESULTS: The mean value of lumbar lordosis was 34.46degrees+/-12.61degrees in female students and 22.46degrees+/-9.9degrees in male students. The mean value of lumbar lordosis significantly differed between female and male students (p<0.001). However, there was no difference in the level of the thoracic curve (p=0.288). Relationship between kyphosis measured by using a flexible ruler and inter-scapular pain in male and female students was not significant (p=0.946). However, the relationship between lumbar lordosis and low back pain was statistically significant (p=0.006). Also, no significant relationship was observed between abnormal kyphosis and frequency of inter-scapular pain, and between lumbar lordosis and low back pain. CONCLUSIONS: Lumbar lordosis contributes to low back pain. The causes of musculoskeletal pain could be muscle imbalance and muscle and ligament strain.
Animals ; Female ; Humans ; Kyphosis* ; Ligaments ; Lordosis* ; Low Back Pain ; Male ; Musculoskeletal Pain ; Posture ; Spine ; Visual Analog Scale ; Surveys and Questionnaires

OBJECTIVES: Preterm birth (PTB) is a leading cause of neonatal death and the second biggest cause of death in children under five years of age. The objective of this study was to determine the prevalence of PTB and its associated factors using logistic regression and decision tree classification methods. METHODS: This cross-sectional study was conducted on 4,415 pregnant women in Tehran, Iran, from July 6–21, 2015. Data were collected by a researcher-developed questionnaire through interviews with mothers and review of their medical records. To evaluate the accuracy of the logistic regression and decision tree methods, several indices such as sensitivity, specificity, and the area under the curve were used. RESULTS: The PTB rate was 5.5% in this study. The logistic regression outperformed the decision tree for the classification of PTB based on risk factors. Logistic regression showed that multiple pregnancies, mothers with preeclampsia, and those who conceived with assisted reproductive technology had an increased risk for PTB (p < 0.05). CONCLUSION: Identifying and training mothers at risk as well as improving prenatal care may reduce the PTB rate. We also recommend that statisticians utilize the logistic regression model for the classification of risk groups for PTB.
Cause of Death ; Child ; Classification ; Cross-Sectional Studies ; Decision Trees* ; Female ; Humans ; Infant ; Iran* ; Logistic Models* ; Medical Records ; Methods* ; Mothers ; Perinatal Death ; Pre-Eclampsia ; Pregnancy ; Pregnancy, Multiple ; Pregnant Women ; Premature Birth* ; Prenatal Care ; Prevalence* ; Reproductive Techniques, Assisted ; Risk Factors ; Sensitivity and Specificity

Objectives: Tuberculosis (TB) is a major public health concern worldwide. Social contact patterns can affect the epidemiology and risk of airborne diseases such as TB. This study was designed to investigate the social contact patterns associated with TB. Methods: In this case-control study, groups of participants with and without TB were matched by age and sex. Participants reported the nature, location, frequency, and average duration of social contacts over 1 month. The duration and number of social and spatial contacts were compared between groups using the chi-square test and the t-test. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to quantify the relationship between social contact time and TB status. Data were analyzed using Stata version 11 statistical software. A p-value of <0.05 was considered to indicate statistical significance. Results: In this study, 80 patients with TB and 172 control participants were included, and a total of 3545 social contacts were registered. Social contact with family members (OR, 1.72; 95% CI, 1.10 to 2.40), contact with a person with TB (OR, 1.53; 95% CI, 1.16 to 2.01), and contact at the participant’s home (OR, 1.42; 95% CI, 1.19 to 1.82) were significantly associated with TB status. Conclusions The duration of long-term social contact, rather than the number of contacts, may be the main contact-related factor associated with TB transmission in this population. The focus of contact-tracing efforts should be on finding and treating both family members and long-term contacts in non-household settings.

OBJECTIVES: Over the past few decades, the prevalence of cesarean sections (CS) have risen dramatically worldwide, particularly in Iran. The aim of this study was to determine the prevalence of CS in Tehran, and to examine the associated risk factors. METHODS: A cross-sectional study of 4,308 pregnant women with singleton live-births in Tehran, Iran, between July 6–21, 2015 was performed. Multilevel logistic regression analysis was performed using demographic and obstetrical variables at the first level, and hospitals as a variable at the second level. RESULTS: The incidence of CS was 72.0%. Multivariate analysis showed a significant relationship between CS and the mother's age, socioeconomic status, body mass index, parity, type of pregnancy, preeclampsia, infant height, and baby's head circumference. The intra-class correlation using the second level variable, the hospital was 0.292, indicating approximately 29.2% of the total variation in the response variable accounted for by the hospital. CONCLUSION: The incidence of CS was substantially higher than other countries. Therefore, educational and psychological interventions are necessary to reduce CS rates amongst pregnant Iranian women.
Body Mass Index ; Cesarean Section* ; Cross-Sectional Studies ; Female ; Head ; Humans ; Incidence ; Infant ; Iran* ; Logistic Models* ; Multivariate Analysis ; Parity ; Pre-Eclampsia ; Pregnancy ; Pregnant Women ; Prevalence ; Risk Factors ; Social Class

Introduction: Breast cancer is the most common cancer and it is the second leading cause of cancer mortality for women after lung cancer in Iran. Given the high prevalence of breast cancer, it is of crucial importance to determine reproductive risk factors of breast cancer. Methods: A total of 139 female patients suffering from breast cancer (the case group) and 279 healthy females (the control group) who were age-matched participated in the study over the period from March 2018 to March 2019. Demographic and reproductive variables, including the number of pregnancies, breastfeeding, history of oral contraceptive use, abortion history, age at first menstruation and age at first childbirth, were all recorded via survey. Conditional Logistic regression was employed to calculate OR (CI: 95%). Results: The mean age of breast cancer patients was 50.8 ± 8.31. First degree family history of breast cancer, History of oral contraceptive use and delaying first pregnancy drastically increased the chance of breast cancer whereas breastfeeding and menstruation after the age of 14 reduced the chance of breast cancer. Conclusion: The findings of this study reveal that the age at first birth, use of oral contraceptives, first degree family history of breast cancer and lack of breastfeeding have a significant relationship with breast cancer. Thus, women who have experienced such factors are susceptible to breast cancer and need to be prioritized for preventive treatments and screening.