Verification Bias Correction in Endometrial Abnormalities in Infertile Women Referred to Royan Institute Using Statistical Methods.

Background: Verification bias is a common bias in the diagnostic accuracy of diagnostic tests and occurs when a number of individuals do not perform the gold standard test. In this study, we review the correcting methods of verification bias. Methods: In a cross-sectional study in 2020, 567 infertile women who were referred to Royan Research Institute were evaluated. The ultrasound is the performed test and the gold standard are hysteroscopy for some, and pathology for other abnormalities. For correcting verification bias conventional, Begg and Greens, Zhou, and logistic regression methods were used. Results: In the gold standard hysteroscopy test, the sensitivity (SEN) and specificity (SPEC) obtained in conventional, Begg and Greens, Zhou, and logistics Regression methods were (50%, 90.3%), (48%, 96%), (22%, 77%), (50%, 90%), and (72.8, 77) respectively. Furthermore, the area under the curve (AUC) index and kappa statistics were calculated as 70.2%, and 43.6% respectively. In the pathology gold standard test, the SEN and SPEC for the conventional methods, Begg and Greens, Zhou and logistics regression were (67.7%, 86.7%), (66%, 88%), (29%, 70%), (66.9%, 87.6%), and (73%, 83.9%) respectively. Also, the AUC index and kappa statistics were 77%, and 55% respectively. Conclusion: In the study on endometrial abnormalities in infertile women, assuming that the missing data mechanism is random, the amount of bias in calculating SEN and SPEC is very low in the diagnostic tests calculated before and after correction, using Begg and Greens and logistic regression method. But Zhou's method gives rather large biased estimates.

Prediction of Intraperitoneal Adhesions in Repeated Cesarean Section Using Sliding Sign, Striae Gravidarum, and Cesarean Scar.

Background: Intraabdominal adhesions are associated with an increase in complications during cesarean section because of recurrent cesarean sections. This is why the possibility of predicting adhesions is important. In this study, the diagnostic value of depressed scar, severe striae gravidarum, and negative sliding sign, and their combinations were evaluated for predicting intraabdominal adhesions of cesarean candidates. Methods: This prospective descriptive study was performed during 2019-2020 on 123 pregnant women referred to Ayatollah Taleghani university hospital with a gestational age of ≥36 weeks 0 days who were candidates for cesarean section because of a previous cesarean section. In each patient, the presence of a depressed scar, a severe striae gravidarum, the absence of a sliding sign, and the presence and severity of adhesions during the operation were examined. Sensitivity and specificity, and positive and negative predictive values of each of the 3 indicators and their combinations were calculated. Results: The frequency distribution of severe adhesion in these individuals was 16.27%. The highest sensitivity was related to depressed scar and negative sliding sign (65%). The highest specificity was related to the negative sliding sign and its combinations (97%-99%). The highest positive predictive value was related to negative sign sliding and its combinations (81%-92%). The negative predictive values of depressed scar, negative sliding sign, and severe striae gravidarum, and even their combinations were almost the same and approximately between 89% and 93%. Conclusion: To predict the presence of adhesions in a cesarean candidate because of a previous cesarean section, you should first examine the striae gravidarum and scar. In the absence of a depressed scar and severe striae gravidarum, there is a 90% chance of no adhesions. According to this study, if both signs are present, it is recommended to check the sliding sign to obtain a more accurate estimate.

Comparison of the effects of Lactobacillus plantarum versus imipenem on infected burn wound healing.

Background: Infection of burn wounds is one of the most important problems in the world. Lactobacillus plantarum is known for burn wound healing because of the immunomodulatory and anti-microbial roles. This study was performed to compare the effects of L. plantarum and imipenem - alone and in combination - on infected burn wound healing. Methods: Burn wounds were experimentally induced on 50 rats in three test groups (germ and supernatant of L. plantarum ) and two control groups (n=10 each) and were inoculated with Pseudomonas aeruginosa. During a 14-day period, wounds in all groups were daily treated topically. The data were analyzed using one-way analysis of variance followed by Tukey-Kramer and LSD. A p-value of < 0.05 was considered as statistically significant. Results: The mean size of the wound on day 14 after the treatment in the probiotic group was significantly lower than the control and the supernatant treated groups (p<0.05). The percentage of wound healing was significantly higher in the probiotic pellet treated group compared to the imipenem and the supernatant groups (by Anova test: 69.58%, p=0.022). The mean leukocyte count in the probiotic pellet group (12110) and supernatant group (13650) was significantly higher than the imipenem group (7670) (p=0.002 and 0.001, respectively). Wound cultures revealed that the percentage of cases where the pathogens had no growth was significantly different among the comparison groups. In all three test groups, P. aeruginosa was completely eliminated in comparison to the positive control group (p<0.05). Conclusion: The results of our study showed that L. plantarum and its by-products promote wound healing and can be used as an alternative to antibiotics to treat ulcer infections caused by resistant bacteria.

Factors affecting emergency medical dispatchers' decision-making: a qualitative study.

INTRODUCTION: Prehospital emergency medical service dispatchers should make prompt and appropriate decisions to save the life of victims. The complexity of timely and reasonable decision-making in life-threatening conditions has driven researchers to investigate varying aspects of the emergency medical dispatch (EMD) process. The purpose of this study was to explore the contributors to appropriate and prompt decision-making among dispatchers. METHODS: A qualitative study through thematic analysis was designed. Data were collected using observation and semistructured interviews with 16 authorities and dispatchers in seven EMDs across Iran. RESULTS: The study found "responsiveness" as the main category contributing to improved decision-making in EMD. The components introduced in this study for dispatchers' responsiveness consisted of two categories. The first was "personal values" including faith and belief, eagerness to help, service excellence, altruism, respect, and impartiality in clinical judgment. The second was "professional attitudes" resulting from education and experience, including the recognition of emergency as a threat to health, sensitivity in triage, response to all requests for help, care for early warnings, commitment to organizational goals and standards, attention to the emergency medical service social support responsibility, and professional temperance. CONCLUSION: In this study, responsiveness was identified as a main category in improving the decision-making process among dispatchers. To attain responsiveness, institutionalization of its values and establishment of EMD-specific professional attitudes in dispatchers should be taken into consideration.

How Do Voice Perceptual Changes Predict Acoustic Parameters in Persian Voice Patients?

INTRODUCTION: Perceptual and acoustic analyses are essential tools that help voice therapists comprehensively assess voice quality. While perceptual evaluations are subjective and are influenced by external and culturally driven factors, acoustic analysis is an objective and reliable means of evaluating voice. The goals of this study were (1) to determine which acoustic parameters were predicted by perceptual voice quality and (2) to assess the effect of a short period of training on the reliability of perceptual voice analyses for Persian speakers. METHOD: This was a cross-sectional study. Subjects were 20 patients with various voice disorders. Voice samples were obtained during text reading and /a/ prolongation. Fifteen expert voice clinicians completed perceptual evaluations on voice samples using the Grade, Roughness, Breathiness, Asthenia, and Strain scale. We repeated this process after a short period of perceptual voice evaluation training. Acoustic analysis was completed using the Praat program. We used the intraclass correlation coefficient (ICC) for reliability measurement of the perceptual evaluation results and ordinal regression procedures to analyze all data. Significance level was set at P < 0.05. RESULTS: Both intrarater and interrater reliability increased after training, for all five parameters. The ICC for grade increased to 0.95 after training. Grade and roughness significantly predicted fundamental frequency (F0) (P = 0.021 and P = 0.030, respectively) and harmonic-to-noise ratio (HNR) (P = 0.019 and P = 0.016, respectively). Breathiness significantly predicted shimmer (P = 0.013). CONCLUSION: Training had a positive effect and increased the reliability of perceptual voice evaluation. For Persian listeners, changes in F0, increases in HNR, and shimmer were perceptually associated with poor voice quality.

Factors affecting smartphone adoption for accessing information in medical settings.

OBJECTIVES: This study aimed to acquire knowledge about the factors affecting smartphone adoption for accessing information in medical settings in Iranian Hospitals. METHODS: A qualitative and quantitative approach was used to conduct this study. Semi-structured interviews were conducted with 21 medical residents and interns in 2013 to identify determinant factors for smartphone adoption. Afterwards, nine relationships were hypothesised. We developed a questionnaire to test these hypotheses and to evaluate the importance of each factor. Structural equation modelling was used to analyse the causal relations between model parameters and to accurately identify determinant factors. RESULTS: Eight factors were identified in the qualitative phase of the study, including perceived usefulness, perceived ease of use, training, internal environment, personal experience, social impacts, observability and job related characteristics. Among the studied factors, perceived usefulness, personal experience and job related characteristics were significantly associated with attitude to use a smartphone which accounted for 64% of the variance in attitude. Perceived usefulness had the strongest impact on attitude to use a smartphone. CONCLUSION: The factors that emerged from interviews were consistent with the Technology Acceptance Model (TAM) and some previous studies. TAM is a reliable model for understanding the factors of smartphone acceptance in medical settings.

Artificial neural networks versus bivariate logistic regression in prediction diagnosis of patients with hypertension and diabetes.

BACKGROUND: Diabetes and hypertension are important non-communicable diseases and their prevalence is important for health authorities. The aim of this study was to determine the predictive precision of the bivariate Logistic Regression (LR) and Artificial Neutral Network (ANN) in concurrent diagnosis of diabetes and hypertension. METHODS: This cross-sectional study was performed with 12000 Iranian people in 2013 using stratified- cluster sampling. The research questionnaire included information on hypertension and diabetes and their risk factors. A perceptron ANN with two hidden layers was applied to data. To build a joint LR model and ANN, SAS 9.2 and Matlab software were used. The AUC was used to find the higher accurate model for predicting diabetes and hypertension. RESULTS: The variables of gender, type of cooking oil, physical activity, family history, age, passive smokers and obesity entered to the LR model and ANN. The odds ratios of affliction to both diabetes and hypertension is high in females, users of solid oil, with no physical activity, with positive family history, age of equal or higher than 55, passive smokers and those with obesity. The AUC for LR model and ANN were 0.78 (p=0.039) and 0.86 (p=0.046), respectively. CONCLUSION: The best model for concurrent affliction to hypertension and diabetes is ANN which has higher accuracy than the bivariate LR model.

Ranking Iranian biomedical research centers according to H-variants (G, M, A, R) in Scopus and Web of Science.

BACKGROUND: We conducted a comprehensive bibliometrics analysis to calculate the H, G, M, A and R indicators for all Iranian biomedical research centers (IBRCs) from the output of ISI Web of Science (WoS) and Scopus between 1991 and 2010. We compared the research performance of the research centers according to these indicators. METHODS: This was a cross-sectional and descriptive-analytical study, conducted on 104 Iranian biomedical research centers between August and September 2011. We collected our data through Scopus and WoS. Pearson correlation coefficient between the scientometrics indicators was calculated using SPSS, version 16. RESULTS: The mean values of all indicators were higher in Scopus than in WoS. Drug Applied Research Center of Tabriz University of Medical Sciences had the highest number of publications in both WoS and Scopus databases. This research center along with Royan Institute received the highest number of citations in both Scopus and WoS, respectively. The highest correlation was seen between G and R (.998) in WoS and between G and R (.990) in Scopus. Furthermore, the highest overlap of the 10 top IBRCs was between G and H in WoS (100%) and between G-R (90%) and H-R (90%) in Scopus. CONCLUSION: Research centers affiliated to the top ranked Iranian medical universities obtained a better position with respect to the studied scientometrics indicators. All aforementioned indicators are important for ranking bibliometrics studies as they refer to different attributes of scientific output and citation aspects.

Health Information Economy: Literature Review.

INTRODUCTION: Health Information Economy (HIE) is one of the broader, more complex, and challenging and yet important topics in the field of health science that requires the identification of its dimensions for planning and policy making. The aim of this study was to determine HIE concept dimensions. METHODS: This paper presents a systematic methodology for analyzing the trends of HIE. For this purpose, the main keywords of this area were identified and searched in the databases and from among 4775 retrieved sources, 12 sources were studied in the field of HIE. RESULTS: Information Economy (IE) in the world has passed behind four paradigms that involve the information evaluation perspective, the information technology perspective, the asymmetric information perspective and information value perspective. In this research, the fourth perspective in the HIE was analyzed. The main findings of this research were categorized in three major groups, including the flow of information process in the field of health (production. collection, processing and dissemination), and information applications in the same field (education, research, health industry, policy, legislation, and decision-making) and the underlying fields. CONCLUSION: According to the findings, HIE has already developed a theoretical and conceptual gap that due to its importance in the next decade would be one of the research approaches to health science.

Prediction of breast cancer survival through knowledge discovery in databases.

The collection of large volumes of medical data has offered an opportunity to develop prediction models for survival by the medical research community. Medical researchers who seek to discover and extract hidden patterns and relationships among large number of variables use knowledge discovery in databases (KDD) to predict the outcome of a disease. The study was conducted to develop predictive models and discover relationships between certain predictor variables and survival in the context of breast cancer. This study is Cross sectional. After data preparation, data of 22,763 female patients, mean age 59.4 years, stored in the Surveillance Epidemiology and End Results (SEER) breast cancer dataset were analyzed anonymously. IBM SPSS Statistics 16, Access 2003 and Excel 2003 were used in the data preparation and IBM SPSS Modeler 14.2 was used in the model design. Support Vector Machine (SVM) model outperformed other models in the prediction of breast cancer survival. Analysis showed SVM model detected ten important predictor variables contributing mostly to prediction of breast cancer survival. Among important variables, behavior of tumor as the most important variable and stage of malignancy as the least important variable were identified. In current study, applying of the knowledge discovery method in the breast cancer dataset predicted the survival condition of breast cancer patients with high confidence and identified the most important variables participating in breast cancer survival.

Managing the security of nursing data in the electronic health record.

BACKGROUND: The Electronic Health Record (EHR) is a patient care information resource for clinicians and nursing documentation is an essential part of comprehensive patient care. Ensuring privacy and the security of health information is a key component to building the trust required to realize the potential benefits of electronic health information exchange. This study was aimed to manage nursing data security in the EHR and also discover the viewpoints of hospital information system vendors (computer companies) and hospital information technology specialists about nursing data security. METHODS: This research is a cross sectional analytic-descriptive study. The study populations were IT experts at the academic hospitals and computer companies of Tehran city in Iran. Data was collected by a self-developed questionnaire whose validity and reliability were confirmed using the experts' opinions and Cronbach's alpha coefficient respectively. Data was analyzed through Spss Version 18 and by descriptive and analytic statistics. RESULTS: The findings of the study revealed that user name and password were the most important methods to authenticate the nurses, with mean percent of 95% and 80%, respectively, and also the most significant level of information security protection were assigned to administrative and logical controls. There was no significant difference between opinions of both groups studied about the levels of information security protection and security requirements (p>0.05). Moreover the access to servers by authorized people, periodic security update, and the application of authentication and authorization were defined as the most basic security requirements from the viewpoint of more than 88 percent of recently-mentioned participants. CONCLUSIONS: Computer companies as system designers and hospitals information technology specialists as systems users and stakeholders present many important views about security requirements for EHR systems and nursing electronic documentation systems. Prioritizing of these requirements helps policy makers to decide what to do when planning for EHR implementation. Therefore, to make appropriate security decisions and to achieve the expected level of protection of the electronic nursing information, it is suggested to consider the priorities of both groups of experts about security principles and also discuss the issues seem to be different between two groups of participants in the research.

The clinical results of benign bone tumor treatment with allograft or autograft.

BACKGROUNDS: Curettage and bone grafting is a method which can eliminate benign bone tumors while restoring structural integrity, reducing the risk of pathological fractures. The aim of this research is to study the clinical outcomes of using allografts and autografts, in treating benign bone neoplasms. METHODS: A Historical Cohort was conducted on 119 patients with benign bone tumors treated with curettage and grafting from 2005 to 2011 in Shafa Yahyaiyan Hospital. The variables were age, gender, tumor type and location, staging, graft type, bone incorporation and recurrence. Data was analyzed with SPSS software, using descriptive statistics, tables, Fisher exact and LogRank tests. The significance level was chosen to be less than 0.05. The study was approved in Iran University of Medical Sciences. RESULTS: One hundred and nineteen patients, consisting of 63 treated with an allograft and 56 treated with an autograft were studied with a mean follow up of 37.5 months. 96.6% of the patients had complete incorporation of the graft into host bone after 6 months of surgery. There was no significant relationship between graft type and bone incorporation (P = 0.121). The estimated median time of recurrence was 20 months (SE= 6.55) in the allograft group and 9 months (SE= 0.77) in the autograft group using survival analysis. Using LogRank test, there was no significant difference between the median in the two methods (P = 0.288). CONCLUSION: Autografts and allografts seem to yield similar success rates in the treatment of benign bone tumors. Although more detailed researches with higher sample sizes are recommended for future studies.

Zero inflated Poisson and negative binomial regression models: application in education.

BACKGROUND: The number of failed courses and semesters in students are indicators of their performance. These amounts have zero inflated (ZI) distributions. Using ZI Poisson and negative binomial distributions we can model these count data to find the associated factors and estimate the parameters. This study aims at to investigate the important factors related to the educational performance of students. METHODS: This cross-sectional study performed in 2008-2009 at Iran University of Medical Sciences (IUMS) with a population of almost 6000 students, 670 students selected using stratified random sampling. The educational and demographical data were collected using the University records. The study design was approved at IUMS and the students' data kept confidential. The descriptive statistics and ZI Poisson and negative binomial regressions were used to analyze the data. The data were analyzed using STATA. RESULTS: In the number of failed semesters, Poisson and negative binomial distributions with ZI, students' total average and quota system had the most roles. For the number of failed courses, total average, and being in undergraduate or master levels had the most effect in both models. CONCLUSION: In all models the total average have the most effect on the number of failed courses or semesters. The next important factor is quota system in failed semester and undergraduate and master levels in failed courses. Therefore, average has an important inverse effect on the numbers of failed courses and semester.

The effective factors on the academic progress of the students of Tehran University of Medical Science.

OBJECTIVE: To examine factors influencing the academic performance of students at Tehran University of Medical Sciences. METHODS: The retrospective cross-sectional study was conducted between 2008 and 2009 at the Tehran University of Medical Sciences, Iran. Data was obtained from the education office of the university and SPSS version 15 was used for data analysis. RESULTS: Of the 670 students in the study, 230 (34.3%) were boys and 440 (65.6%) were girls.The highest mean score of courses belonged to the Psychiatry Institute (18.68) and the lowest was in the School of Medicine (15.20). Twenty nine per cent of students had failed course and 8.4% had failed semester. CONCLUSION: The variables gender, level of education, and school are the most important factors affecting the educational progress of students. Overall, students' failure ratios varied significantly between schools and educational levels.

Evaluation of the Effect of NT-3 and Biodegradable Poly-L-lactic Acid Nanofiber Scaffolds on Differentiation of Rat Hair Follicle Stem Cells into Neural Cells In Vitro.

Recent improvement in neuroscience has led to new strategies in neural repair. Hair follicle stem cells are high promising source of accessible, active, and pluripotent adult stem cells. They have high affinity to differentiate to neurons. Aside from using cell-scaffold combinations for implantation, scaffolds can provide a suitable microenvironment for cell proliferation, migration, and differentiation. NT-3 is the most interesting neurotrophic factors being an important regulator of neural survival and differentiation. Since treatment duration in neural repair is very important, this study aims to evaluate the effect of NT-3 and poly-L-lactic acid (PLLA) on differentiation time of bulge stem cells of rat hair follicle to neural-like cells. HFSCs of rat whisker was isolated and cultured on PLLA and differentiated with 10 ng/mL NT-3. Biological features of cultured cells were evaluated with immunocytochemistry and flowcytometry methods by using CD34, nestin, and ßІІІ-tubulin markers. For cell viability and morphological assessment, MTT assay and SEM were performed. Our results showed that bulge stem cells of hair follicle can express CD34 and Nestin before differentiation. By using NT-3 during differentiation process, the cells showed positive reaction to ßІІІ-tubulin antibody. MTT results demonstrated that PLLA significantly increased cell viability. Finally, HFSCs adhesion was confirmed by SEM results. The results indicate that 10 ng/mL NT-3 and PLLA have significant effect on differentiation time of rat HFSCs to neural cells even in 10 days.

Estimation of hazard function and its associated factors in gastric cancer patients using wavelet and kernel smoothing methods.

BACKGROUND AND OBJECTIVES: Increase of mortality rates of gastric cancer in Iran and the world in recent years reveal necessity of studies on this disease. Here, hazard function for gastric cancer patients was estimated using Wavelet and Kernel methods and some related factors were assessed. MATERIALS AND METHODS: Ninety- five gastric cancer patients in Fayazbakhsh Hospital between 1996 and 2003 were studied. The effects of age of patients, gender, stage of disease and treatment method on patient's lifetime were assessed. For data analyses, survival analyses using Wavelet method and Log-rank test in R software were used. RESULTS: Nearly 25.3% of patients were female. Fourteen percent had surgery treatment and the rest had treatment without surgery. Three fourths died and the rest were censored. Almost 9.5% of patients were in early stages of the disease, 53.7% in locally advance stage and 36.8% in metastatic stage. Hazard function estimation with the wavelet method showed significant difference for stages of disease (P<0.001) and did not reveal any significant difference for age, gender and treatment method. CONCLUSION: Only stage of disease had effects on hazard and most patients were diagnosed in late stages of disease, which is possibly one of the most reasons for high hazard rate and low survival. Therefore, it seems to be necessary a public education about symptoms of disease by media and regular tests and screening for early diagnosis.

The survival analysis of beta thalassemia major patients in South East of Iran.

OBJECTIVE: To determine the survival of beta-thalassemia major patients with transfusion, and its related factors in Southeast of Iran. METHODS: This cross-sectional study was performed in Zahedan, Iran, in 2007. The sample included patients who were referred from all over the Zahedan Thalassemia Center from 1998 to 2006. The data were collected using the patients' records, which were recorded by the staff during transfusion. The data included demographic and medical information blood group, blood RH, the kind of transfused blood [KTB], annual number of transfusions [ANOT], accompanied diseases [AD], Hemoglobin [Hb] and ferritin level. For data analysis, the Kaplan-Meyer method, and Log Rank test together with Cox Regression were used. RESULTS: Forty-six of 578 patients died and 99% had survived for the first year. The ages survival proportions were 5 (97.9%), 10 97%, 15 (92.1%), and 20 (81.2%) years. The survival time showed significant relationships with the ANOT p=0.0053, KTB p=0.003, Hb p=0.002 and ferritin level p=0.0087, and AD p=0.000. CONCLUSION: Using regular transfusion, paying attention to screening of transfused blood, increasing the families' knowledge on the disease to prevent the bearing of thalassemia fetus, are recommended; finally, the detection and treating of the AD, are of great importance to extend the lifetime of the patients.

Determination of the leading central obesity index among cardiovascular risk factors in Iranian women.

BACKGROUND: It is unknown whether the waist circumference (WC) or the waist-to-hip ratio (WHR) is a better predictor of cardiovascular risk factors at different ages. OBJECTIVE: To compare WC and WHR as predictors of cardiovascular risk factors and to determine the prevalence of some cardiovascular risk factors in overweight and obese adult women at different ages. METHODS: In this clinical cross-sectional study, 714 overweight and obese women aged 20 to 70 years who were referred to two nutrition clinics in Sistan and Baluchestan province, Islamic Republic of Iran, were studied. The subjects were classified into three groups, 20 to < 35, 35 to < 50, and > or = 50 years of age. Anthropometric indices were measured according to the standard protocol. Total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and TC/HDL-C ratios were enzymatically determined. RESULTS: Older subjects (> or = 50 years old) had significantly higher values of body mass index (BMI), WC, TC, TG, and LDL-C than those in the two younger age classes. The prevalence rates of obesity, high WC, high WHR, high TC, high TG, high LDL-C, and high TC/ HDL-C ratios were higher in the older subjects. After adjustment for age and BMI, multiple linear regression showed that WC was significantly related to TC and TG in the 20- to < 35-year-old group and to TG in the 35- to < 50-year-old group. In the older participants, WHR was significantly related to TG. CONCLUSIONS: The prevalence of cardiovascular risk factors increases with age. In clinical practice, WC is a better index for predicting some cardiovascular risk factors in younger and middle-aged women; however, for older women, WHR is better.