Iranian Journal of

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Epidemiological studies of cancer is the corner stone of cancer control plans and necessary for setting goals, monitoring the progress, and evaluating the results of control efforts. Cancer is a generic name for a number of diseases that have different etiology, natural history, and outcome. Thus, control activities for each cancer is different and requires varied approaches. Primary prevention, i.e., controlling the initiation of cancers is now possible for a number of cancers including lung, stomach, liver, and cervix by controlling the use of tobacco, and infections with Helicobacter pylori, Hepatitis C, and Human papilloma viruses. Secondary prevention, i.e., early detection is mostly effective for the cancers of the breast (mammography), cervix (Pap test), prostate (digital rectal exam and PSA testing), colon and rectum (Colon- and Sigmoidscopy), and melanoma of the skin (clinical examination of the skin). Effective treatment is now possible for a large number of cancers with arrays of new medications such as Tamoxifen and Herceptin for breast cancer, Avastin for Colorectal and other cancers, and so on. Tertiary prevention, i.e., rehabilitation and hospice care is a necessary part of cancer control that is generally neglected. Cancer is a familial disease and when it struck, it affects the whole family. Health education and social support for the patients and their families is an integral part of cancer control activities and must be present in any effective cancer control program. Tertiary prevention not only includes proper palliative care, but also education and support for proper nutrition and improvement of the quality of life for the patient and the family.

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Background and Objectives: Logistic regression is one of the most widely used generalized linear models for analysis of the relationships between one or more explanatory variables and a categorical response. Strong correlations among explanatory variables (multicollinearity) reduce the efficiency of model to a considerable degree. In this study we used latent variables to reduce the effects of multicollinearity in the analysis of a case-control study.
Methods: Our data came from a case-control study in which 300 women with breast cancer were compared to 300 controls. Five highly correlated quantitative variables were selected to assess the effect of multicollinearity. First, an ordinary logistic regression model was fitted to the data. Then, to remove the effect of multicollinearity, two latent variables were generated using factor analysis and principal components analysis methods. Parameters of logistic regression were estimated using these latent as explanatory variables. We used the estimated standard errors of the parameters to compare the efficiency of models.
Results: The logistic regression based on five primary variables produced unusual odds ratio estimates for age at first pregnancy (OR=67960, 95%CI: 10184-453503) and for total length of breast feeding (OR=0). On the other hand, the parameters estimated for logistic regression on latent variables generated by both factor analysis and principal components analysis were statistically significant (P<0.003). The standard errors were smaller than with ordinary logistic regression on original variables. The factors and components generated by the two methods explained at least 85% of the total variance.
Conclusions: This research showed that the standard errors of the estimated parameters in logistic regression based on latent variables were considerably smaller than that of model for original variables. Therefore models including latent variables could be more efficient when there is multicollinearity among the risk factors for breast cancer.

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Background and objectives: There is growing interest in assessing gene-environment interaction in the course of case-control studies. Difficulties related to the sampling of controls have led to the development of a range of non-traditional methods that do not require controls for estimating gene-environment interaction. One of these new modalities is the case-only approach, in which the assessment of gene-environment interaction is based on information from the cases only. The present article describes the application of this approach to data from breast cancer patients and compares its efficacy with that of a traditional case-control analysis.
Methods: We used age at first pregnancy, number of live birth, menopause and the total number of post-menopausal years as the "environment" factors and family history of breast cancer as the "gene" factor. We computed standard errors, 95% confidence intervals and (-2 log likelihood) to compare efficiency between case-control and case-only analyses.
Results: We observed significant interaction between menopause and family history of breast cancer by both methods (OR=4.32 CI: 1.10-16.90 for case-control analysis & OR=3.40 CI: 1.17-9.87 for case-only analysis). There was also a significant interaction effect between total years after menopause and family history of breast cancer (OR=1.07 CI: 0.98-1.16 in case-control analysis & OR=1.07 CI: 1.01-1.12 in case-only analysis). The case-only approach yielded narrower confidence intervals for the odds ratio, and the (-2 log likelihood) values computed by this method were correspondingly smaller.
Conclusions: Comparison of confidence intervals and (-2 log likelihood) values shows that the estimation of gene-environment interaction in breast cancer would be more efficient with the case-only approach than with the traditional case-control analysis.

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Background & Objectives: To determine the prevalence of HBV infection in the Golestan Province (southeastern part of the Caspian littoral, Iran).
Methods: A single cluster study was conducted in 2005, based on a sample of households, representative of the population aged 25-65 years in Golestan. All participants were invited for face-to-face interviews to gather demographic data. Blood samples were drawn and analyzed for serum markers of HBV infection such as HBsAg and HBcAb by the ELISA method. Factors associated with hepatitis B seroprevalence were analyzed using SPSS13 and STATA /8.
Results: A total of 1850 subjects were screened. The age- & sex-standardized prevalence for HBsAg positivity was 9.7% (95%CI=0.07-0.11). Rates were higher in males than in females (10.8% vs. 8.6%) (OR=1.28 95% CI=0.9-1.7). HBV seroprevalence in unmarried individuals was significantly higher than in those who were married (OR=2.13 95%CI=1.29-3.5). HBsAg(+) status was more frequent in urban areas (OR=1.46 95% CI=0.9-2.3). Thirty-six percent of population was HBcAb positive. HBcAb(+) prevalence was significantly higher in females (OR=1.46 95% CI=1.19-1.8) and married people (OR=1.58 95%CI=1.02-2.45), and also in urban areas (OR=1.34 95% CI=1.09-1.6).
Conclusions: This study shows that the prevalence of HBsAg(+) status in the Iranian province of Golestan is at a level regarded as "high" by the World Health Organization. It is higher than reported by pervious studies in Iran so it is important- especially for health providers and policy makers- to recognize risk factors and design appropriate prevention programs.

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Background and Objectives: There are conflicting data on the effects of different types of fat on aortic atherosclerosis. This study used Wister rats to compare the atherogenic effects of a standard diet with a diet containing fish oil and another diet containing mixed oils (typical of the current consumption pattern in Iran).
Methods: Thirty female Wistar rats were randomly assigned to three diet groups: a standard diet (containing soy bean-oil as the only dietary fat), a diet containing fish oil and another diet which contained mixed oils and was designed on the basis of the current fat consumption pattern in Iran (butter, hydrogenated vegetable oil and sunflower oil). Mothers in each group were fed the same diet during pregnancy and lactation the litters were also weaned onto the same diet. Aortic samples were taken from the offspring at the time of weaning and puberty. Data were analyzed using SPSS software Kruskal-Wallis test was applied for comparison among groups.
Results: Rats that were fed soy bean oil showed less extensive fatty streaks and intimal thickening of aorta on weaning and at puberty. Rats fed fish oil and mixed oils showed more atherosclerosis lesions compared to those receiving soy bean oil.
Conclusions: It seems that diets with an omega-3 to omega-6 ratio of 0.6 can enhance aortic atherosclerosis. Diets with an Iranian fat consumption pattern also increase aortic atherosclerotic lesions because they contain substantial amounts of saturated fat.

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Background & Objectives: The aim of present study is to compare Afghan refugees and Iranian residents in terms of their knowledge, attitude and practice concerning malaria transmission and protection in an endemic area in Southeast Iran.
Methods: This cross sectional study was conducted over a period of 10 months (2004-2005) and involved a total of 775 people, including Iranian and Afghan subjects. The age range of participants was 15 to 55 years. Data collection was done through a structured questionnaire consisting of open and close questions and comprising several, namely personal characteristics details, history of malaria infection and treatments, type of residence, mobility, self protection, facilities, and access to health services.
Results: Both Iranians and Afghans were familiar with the three typical symptoms of the disease (fever, chills and muscle aches): 67.1% of Iranians and 78% of Afghans were able to name least one of the three typical symptoms. In both groups the majority of subjects were aware that malaria transmission occurs through mosquito bite but there was a significant difference regarding knowledge of malaria transmission (χ2 =142.2, P<0.001). Chi-square test for goodness of fit showed that the distribution of symptom indicators is significantly different between the two groups. For Iranians, the most important source of information about malaria was the health facilities (44.5% of the total) while most Afghans (65.3%) had obtained the information through friends and relatives. In both groups, the mass media had acted as the source of information in only 3.4%. Altogether, 24% of the participants reported the use of mosquito bed nets almost 90% of Afghans and 62% of Iranians said that they did not used bed nets at all. However, the number of Iranians who used bed nets was four times greater than the Afghans who did so.
Conclusions: Although the majority of subjects were familiar with malaria transmission and protection methods, they largely neglected safety precautions. Moreover, it seems that the high prevalence of malaria among Afghans is due to their life style rather than cross-border travel. The study also revealed that Afghan people have poor communication with the local health facilities, a point that must receive special attention in future malaria control programs.

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Background & Objectives: Arsenicosis is a serious environmental disease caused by chronic exposure to arsenic- usually from drinking water. Signs and symptoms of chronic arsenic poisoning include hyperkeratosis, hyper- or hypopigmentation, and ulcers. Also, the incidence of cancer is increased in the exposed population. There is some evidence of high arsenic levels in drinking water in the village of Ghopuz, located in Hashtrud District, East Azerbaijan province. We evaluated the genetic and health effects of chronic arsenic exposure in the residents of Ghopuz.
Methods: In this cross-sectional study we determined the prevalence of hyperkeratosis, hyperpigmentation and hypertension in Ghopuz village. The study involved 101 individuals in Ghopuz and 107 in the adjacent village of Mayan, who were all visited by a trained physician. A total of 46 blood samples were collected for kariotyping. The level of heavy metals in water was determined by the Inductively Coupled Plasma (ICP) method.
Results: We detected high arsenic levels in the drinking water at Ghopuz (mean concentration in water = 1.03 mg/L). There were chromosomal defects in the exposed group. Mean systolic blood pressure at Ghopuz (137mmHg, 95% CI: 132-142) was significantly higher than in Mayan (107, 95% CI: 99.9-114). Also, mean diastolic blood pressure at Ghopuz (82, 95% CI: 79-85) was significantly higher than in Mayan (71, 95% CI: 66-75). Hyperkeratosis was 34 times more frequent in the exposed population (OR = 34, P< 0.001). Also, hyperpigmentation was significantly more frequent in the exposed population (OR = 2.4, P < 0.007).
Conclusions: Water arsenic and nitrate levels at Ghopuz were higher than the maximum permissible levels. The prevalence of skin lesions and hypertension is increased at Ghopuz village due to arsenic exposure. There is also some evidence of chromosomal defects in the exposed group. Affected people need appropriate medical care, and safe drinking water should be provided to reduce arsenic exposure.

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Background & Objectives: Malocclusion is not a disease but rather a set of dental deviations, which in some cases can influence quality of life. The aim of this study was to assess the frequency of various dento–facial anomalies.
Methods: In this cross-sectional study in 2006 we assessed a sample of 600 randomly selected schoolchildren, with a mean age of 11.97 years, who were attending secondary school in various districts of Karaj. We used questionnaires to obtain information on extracted teeth, crowding, spacing, diastem, the severest disorders in anteriors (maxilla and mandible), overjet, negative overjet, open space between two jaws and antero-posterior molar relationship.
Results: Ninety-nine percent of children had no extracted teeth in maxillary anteriors, while 98.3% had no extracted teeth in mandibular anteriors. In 41.2% of the subjects there was no crowding, and 57.7% of the sample had no spacing. The mean diastem was 0.36 mm and the mean of the most severe disorders in anteriors was 1.08 mm in the maxilla and 0.78 mm in the mandible. Mean overjet was 1.98 mm, mean negative overjet 0.03 mm, and mean open space between two jaws was 0.28 mm. In 58.5% of the subjects the antero–posterior molar relationship was normal. The DIA ranged form 13 to 63, with a mean of 24.12.
Conclusions: This study indicates that over than one-third of the population needs different degrees of orthodontic treatment.

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Background & Objective: Disability-Adjusted Life Years (DALY) summarizes the fatal and nonfatal outcomes of diseases and injuries in one number and gives a quantitative assessment of the health of a population. Estimating the burden of diseases and injuries in Iran in terms of DALY both nationwide and in 6 provinces.
Methods: We used slightly modified versions of the methods developed by the World Health Organization for estimating the burden of premature mortality, disability, and the DALY.
Results: The DALY rate per 100,000 was 21572 and 62% of this was life lost due to premature mortality the remaining 38% was due to disability from diseases and injuries. Fifty-eight percent of the total DALYs had been lost due to non-communicable diseases, 28% due to external causes (injuries), and 14% due to communicable, maternal/ perinatal and nutritional illnesses. The group of diseases and injuries with the highest burden in males waz intentional and unintentional injuries (2.789 million DALYs), while in the female population this position was held by mental disorders with 1.191 million DALYs. The single most important cause of burden was traffic accidents in males and ischemic heart disease in females. Disease burden showed considerable variability between different provinces.
Conclusion: The profile of health and disease in Iran has generally shifted from the predominance of communicable, maternal/perinatal, and nutritional illnesses towards predominance of non-communicable diseases and injuries at the national level. These figures on disease burden at population level are the most objective evidence that can be used in policy making and management of health programs, health research, and resource development within the health sector.

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Background & Objectives: The objective of this study was to determine self efficacy, perceived benefit/ barriers to exercise of students in Hormozagan University of Medical sciences (HUMS).
Methods: This was a cross-sectional study. Using stratified sampling, 350 current students of HUMS were studied from November to December 2007 in Bandar Abbass, Iran. Data regarding self efficacy, perceived benefits/barriers to exercise among participants were assessed through Exercise self efficacy scale and Exercise Benefits/Barriers Scale. Data were analyzed by SPPS version 13.
Results: In all, the data of 249 participants with mean age of 21.7 ± 2.7 were analyzed. Among them 65 participants (26.5%) including 36 girls and 30 boys were doing physical activity. Mean scores of self efficacy, perceived benefits, perceived barriers were 23 ± 7.1, 96 ± 12.5 and 31.9 ± 6.1, respectively. There were statistically significant relationship between self efficacy and perceived barriers with physical activity (P<0.05).
Conclusions: This study revealed perceived barriers such as insufficient time, money and also tiredness due of exercise could decrease physical activity. However perceived self-efficacy and encouraging by friends and family members have a key role of doing regular physical activities.

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Background & Objectives: The main purpose of this study was to assess the pulmonary reactions associated with occupational inhalation exposure to raw materials used in ceramic production (RMCP).
Methods: Thirty three male workers with current exposure to RMCP and 20 healthy male unexposed employees, ,with almost identical demographic and socioeconomic status were interviewed and respiratory symptom questionnaires were administered to them. Furthermore, they underwent chest X-ray and lung function tests. Additionally, personal dust monitoring was carried out at dusty work sites. To determine the chemical composition, possible silica phases and SiO2 contents of dust samples, they were analyzed by X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques.
Results: Atmospheric concentrations of dust, that contained 69% SiO2­, exceeded current permissible levels. Additionally, exposed workers had higher prevalence rates of regular cough, wheezing, phlegm and shortness of breath. Likewise, their chest radiographs showed some degrees of abnormalities. Furthermore, significant reductions in some parameters of pulmonary functions of exposed workers were noted.
Conclusions: The findings of this study indicate that a strong association exists between exposure to RMCP, prevalence of respiratory symptoms, abnormal changes in chest radiographs and functional impairments of the lungs.

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Background & Objectives: Recognition of epidemiology of acute myocardial infraction (AMI) in every region could be a need for design the programs for prevention of AMI. In this study we assessed the epidemiology of changes in AMI from 2002-2006 in Birjand(east of Iran).
Methods: All of the patients which hospitalized by AMI diagnosis from 2002-2006 years, included in this study. We compared mean of age, gender, location of living, medications used, condition at discharge and cardiac risk factors in this period.
Results: From 1233 patients, 880 were male (71.4%). Overall, mean age of patients was 62/2±12/8 years and in five years was increased (from 61.7±13/2 in 2002 to 63.5±12/4 in 2006 & p=0.37). The most risk factors in patients were: Hypertension (HTN) (34/8%) ,cigarette smoking (32/1%) & dyslipidemia (24%). These risk factors did not show any significantly changes during 5 years. But the the prevalence of HTN (30/9% in 2002 to 38% in 2006, p=0/62) and DM (15/5% in 2002 to 21% in 2006, p=0/23) raised. Cardiac drugs use tended to increase during 5 years, however only this increase about STK & Statin was statistically significant. The hospital mortality rate was decreased in 5 years (11.3%) but it was not statistically significant (p= 0.48).
Conclusions: Regarding the accelerating the rate of AMI, designing an appropriate prograrme for prevention and modifying cardiac risk factors is recommended.

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Background & Objectives: This study aimed to determine of the seroprevalence of visceral leishmaniasis to design a prevention and control program in Bojnoord district.
Methods: This was a descriptive and cross sectional study with multistage random sampling method. The study was carried out on children up to 12 years old and 10% of adult’s population in 8 rural areas of Bojnoord district in 2007. In total, 1608 blood samples were collected to detect anti-Leishmania antibodies. All the samples were tested by direct agglutination test (DAT). In order to determine Leishmania species, necropsy was performed on four suspected dogs in the studied areas. The species of Leishmania was determined by RAPD-PCR and PCR-RFLP methods using to amplify the ribosomal internal transcribed spacer 1 (ITS1).
Results: Thirty and eight (2.36%) out of 1608 collected blood samples had anti-Leishmania antibodies at titer 1:800 and nine (0.56%) were just positive at 1:3200 by DAT. There was no statistically significant difference between female and male seroprevalence (p<0/05). The seoprevalence in children <=12 years old compared to individuals greater than 12 years old did not show any statistically significant (p<0/05). Amastigotes were observed in all 4 necropsied dogs. The species of Leishmania isolated from 2 dogs, was determined as L.Infantum. Their ITS1 sequences were registered with Accession numbers EU810776 and EU810777 in NCBI.
Conclusions: These findings showed that visceral leishmaniasis has been circulated with low endemicity in Bojnoord district. Therefore an appropriate monitoring system is needed for health services in this area.

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Background & Objectives: Burden of disease studies have been implemented in many countries using the disability adjusted life year (DALY) to assess major health problems. This study was designed to assess the burden of transport accident in South Khorasan (SK) province of Iran for 2005.
Methods: Years of life lost (YLLs), Years lived with Disability (YLDs) and DALYs were calculated by using methodology developed for the global burden of disease study (GBD) in 2003. The total population of SK was included in this study.
Results: In the 2005 year, the DALYs from transport accident in the south Khorasan province were 7456. DALYs for males and females were 5775(77%), 1691(23%) years respectively. The total rate of DALYs was 13.28 (per 1000) and with higher rates in age groups 30-44 years (20/86 per 1000), 15-29 years (16/96 per 1000) and 45-59 years (13/28 per 1000).
Conclusions: The age group 15– 44 years was more at risk of transport accidents and injuries than others. The findings suggest that adequate interventional programs for transport accidents prevention and control should be taken to minimize at different levels.

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Background and objectives: Although in many developed and developing countries, self care is the most important part of primary care, in Iran it has not been supported as well as its values. The aim of this study was to assess the views of general people living in south of Tehran about self care.
Methods: This was a population based study in which 1200 individuals aged 15 years and over were interviewed using cluster sampling. A structured interview questionnaire which including 5 sections on regarding demographic characteristics, views on general health, views on self care knowledge, interest and practice, views on barrier and enabler factors for self care, and views on sources of information was used. Content validity and cronbach’s alpha coefficient was used for its validity and reliability. Data were analyzed through spss version 11.
Results: The mean age of participants was 27.9 ± 5.2 years. Six hundred and fifty eight respondents (55%) stated they were not knowledgeable on self care, 986 (82%) and 1035 (86%), were interested and self rated themselves active regarding healthy life style, respectively. In practice, only fifty three participants (4%) were actually active in eating ≥7 glasses of water daily, 31 (3%) stated they ate more than five portions of fruits daily and 51(4%) did physical activity more than 3 hours weekly.
Conclusions: The findings of this study have highlighted the significant role of information in doing self care activities.

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Background and objectives: People with thalessemia and chronic renal failure on maintenance hemodialysis are prone to blood-born infections, especially hepatitis C due to the long-term transfusion. Recently, hepatitis C has been one of the main health concerns in these patients. The aim of this study was to determine the prevalence of hepatitis C and its risk factors in these groups of patients in Kerman province of Iran.
Methods: HCV RNA in blood sample of 384 patients (203 hemodialysis cases and 181 thalassemia cases) was evaluated.
Results: One hundred thirty (130) out of 384 were infected by HCV. Infected male was predominant (83%).
Conclusions: It seems that the frequency of hepatitis C infection in Kerman is higher than the other provinces of Iran. Therefore more attention should be paid to screen of blood before transfusing for these group of patients.

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Background and Objectives: Anaphylactic reaction is one of the most important transfusion anaphylactic reactions in medicine. During transfusion if Individuals with IgA deficiency take blood which containing IgA, they would suffer from severe allergic reaction. Since there is a little known about this in different ethnic groups in Iran we have decided to evaluate this issue in Sistan & Baluchestan province in Iran. Methods: During one year, blood samples were collected from 3837 volunteer blood donors. Then the serum samples were tested for IgA titer by nephlometry and SRID techniques.
Results: According to our results only, one donor (0.026%) was found to have IgA less than 5mg/dl and 34(0.9%) cases had IgA: 5-30 mg/dl while 3798(99%) had IgA more than 30mg/dl.
Conclusions: With regards to very low prevalence of IgA deficiency in blood donors in Southeast part of Iran, it seems that anaphylactic reactions most likely be due to other factors in the individuals that receive blood products.

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Background & Objective: High prevalence of malnutrition and its relation with mental and physical health of children is one of the important health problems in developing countries. The aim of this survey was to assess the nutritional status and related factors in 0-24 month-old children in South Khorasan province in Iran 2006.
Methods: Seven hundred children of 0-24 month-old in South Khorasan province were included in this survey. A designed questionnaires and face-to-face interview with the mothers were used in order to obtain the required information . In addition, weight (Wt) and height (Ht) of the children were measured and compared with standard charts issued by the American National Center for Health Statistics (NCHS). The nutritional status was determined based on weight for age (Wt/A), height for age (Ht/A), and weight for height (Wt/Ht) indices.
Results: Mean of children's age was 11.1 ± 7.8 month. Based on the Z-score, cut-off point under -2SD from median of the reference population (NCHS), 10.6% of the children were underweight (Wt/A), 5.3% stunted (Ht/A) and 11.6% wasted (Wt/Ht). A statistically significant relationship was found between indices of malnutrition and age and breastfeeding status of children. There was no association between gender and residence of children with their nutritional status.
Conclusion: With regard to prevalence of malnutrition in children, breastfeeding is highly recommended.

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Background & objectives: In the management of crush syndrome, the way of treating compartment syndrome is controversial. The aim of this study was to evaluate the outcomes of compartment syndrome treatment after Bam earthquake.
Methods: Clinical and laboratory findings of all fasciotomized patients in Bam earthquake were analyzed. Then nonfasciotomized patients with same characteristics were selected and the outcomes of two groups were compared.
Results: Fasciotomy for 107 injured out of 2962 hospitalized patients, was performed (46% female). Mean age of fasciotomized patients was 27.4±9.7 years (min=10, max=65 year). There were not significant differences in the final outcome of two groups with the same clinical, biochemical and demographic characteristics.
Conclusions: Fasciotomy for 107 injured out of 2962 hospitalized patients, was performed (46% female). Mean age of fasciotomized patients was 27.4±9.7 years (min=10, max=65 year). There were not significant differences in the final outcome of two groups with the same clinical, biochemical and demographic characteristics.

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Background & Objective: Because of uncertainty in interpretation of some tests for diagnosing TB, decision making for the tuberculosis treatment is based on multiple diagnostic tests. This study was conducted to assess the accuracy of Quanti FERON-TB Gold test in tuberculosis diagnosis.
Methods: The study was carried out on 30 cases and 46 controls. Statistical indices of sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratios, odds ratio and Receiver Operating Characteristics (ROC) curve were estimated.
Results: Sensitivity of QFT-G was 90.0% (95% CI=73.0-97.6), specificity 95.7% (95% CI=83.8-99.3), positive predictive value 93.1% (95% CI=76.3-98.9), negative predictive value 93.6% (95% CI=81.3-98.4). The area under ROC curve was 0.942 (95% CI=0.88-1.00), that significantly differed from chance diagonal area (P<0.0001). The optimum cut point for the Quanti FERON-TB Gold test was 0.35 IU/ml, with sensitivity of 0.90 and specificity of 0.957.
Conclusions: The Quanti FERON-TB Gold test displayed good validity indices in this study. Since the utility of this test has a high cost therefore this test would not be offered for routine tuberculosis detection. It suggested that this test are applicable for smear and culture negative tuberculosis, child tuberculosis, and assessment of TB contact tracing.