Showing 25 results for Control
P Yavari, Ma Mosavizadeh, I B Sadrolhefaz, R Khodabakhshi, H Madani, Y Mehrabi,
Volume 1, Issue 3 (2-2006)
Abstract
Background & Objectives: Breast cancer is a common malignancy in women in many parts of the world. The incidence of breast cancer in Iranian women is growing. Iranian patients are relatively younger than their western counterparts. We conducted a case-control study to determine roles of reproductive factors for breast cancer among women in Iran.
Methods: A hospital based case-control study was conducted in 2004 at a teaching hospital in Tehran, Iran. A total of 303 cases of breast cancer and 303 healthy controls were interviewed. Cases were identified through the oncology department of a university hospital and controls were recruited from other wards or out-patients clinics at the same hospital. Controls were matched to cases on age. Demographic and reproductive data were ascertained by personal interview using a structured questionnaire. Informed consent was obtained from cases and controls. Odds ratios and 95% confidence intervals for breast cancer were derived using logistic regression analysis.
Results: Mean ±SD age of cases and controls was 48.8 ±9.8 and 50.2 ± 11.1 years, respectively (range 24-84). The final model constructed after multivariate analysis indicated that factors such as never being married, menopause, older age at first live birth, parity, use of oral contraceptives, and history of chest X-ray between adolescence and the age of 30 yrs were significantly associated with breast cancer. Variables such as higher education, early age at menarche, abortion, breast feeding and its duration did not constitute significant risk factors.
Conclusions: Marital status, history of chest X-ray between adolescence and the age of 30, number of live births, and age at first live birth, menopause, and oral contraceptive use seem to increase the risk of developing breast cancer among women in Iran.
R Chaman, A Shamshiri, K Kamali, Ghr Khalili, K Holakouie Naieni,
Volume 2, Issue 1 (3-2006)
Abstract
Background & Objectives: This investigation was prompted by the growing importance of nested case-control studies and the increasing frequency with which they are done in epidemiologic research. After a brief explanation of nested case-control studies, we evaluate the trends in research methodology over the last decade, especially with regard to cohort, case-control, and nested case-control designs.
Methods: Data for this study were extracted from the PubMed database, using these keywords: Nested Case-Control, Risk-Set Sampling and Density Sampling. The search was confined to the 10-year period from 1996 to the end of 2005. As for other methodologies, we used keywords Cohort and Case-Control for a search over the same time period. The search itself was performed on April 25, 2006.
Results: We found 2011 articles reporting nested case-control studies. There were 95 such articles in 1996 the number had increased to 289 in 2005. Case-control and cohort designs accounted for 68456 and 60479 articles, respectively.
The number of case-control articles rose from 4378 in 1996 to 10270 in 2005, while that of cohort articles increased from 2981 to 9771 over the same period.
Conclusions: The number of cohort and nested case-control articles followed similar upward trends over the last decade and their rate of increase was greater than that of simple case-control articles.
K Khalaji, R Majdzadeh, Mr Eshraghian, A Motevalian, K Holakouie Naieni,
Volume 2, Issue 1 (3-2006)
Abstract
Background & Objectives: Considering the lack of adequate basic information on risk factors for road traffic injuries in Iran, a study was conducted to determine the association between potential risk factors and the incidence of injuries in motor vehicle drivers.
Methods: We performed a population-based case-control study on Qazvin-Loshan road. Risk factors related to injury incidence were compared between 175 cases and 175 controls. Cases were drivers recently injured in road accidents. Controls did not have any injury and were selected systematically while the study was being conducted. Injury was defined as trauma needing medical or surgical treatment. Information was obtained through police reports and interviews with cases and controls.
Data were analyzed by two methods bivariate analysis (crude) and by a multivariate unconditional logistic regression model.
Results: In bivariate analysis, risk factors for road traffic injuries risk were failure to wear seat belts or protective helmets, ejection from vehicle, severity of collision, number of crashes, motorcycle vs. other motor vehicle accidents, fire, rain and fog, and collision with fixed objects. In the logistic model, factors such as seat belt or helmet use with OR= 0.619 (0.376-1.018), ejection from the vehicle with OR= 2.952 (1.235-7.056), severe collision with OR= 5.413 (2.865-10.224), motorcycle vs. other motor vehicle accident with OR= 3.164 (1.05-9.537) and raining and fog vs. good weather with OR= 4.562 (1.663-12.514) were found to influence injury incidence. There was an interaction between severity of collision and weather status.
Conclusions: Better speed control, use of seat belts or helmets, not using motorcycles for road travel and equipping vehicles with fire extinguishing capsules are recommended to reduce road accident injuries.
P Yavari, Ma Pourhosseingholi,
Volume 2, Issue 1 (3-2006)
Abstract
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.
M Khabazkhoob, A Fotouhi, Mr Majdi, A Moradi, Z Haeri Kermani, M Seyed Nozadi,
Volume 3, Issue 1 (9-2007)
Abstract
Background & Objectives: To determine the risk factors for acute diarrhea disease in children.
Methods: This study involved 220 cases and 220 controls in Dr. Sheykh Hospital, a specialzed pediatric hospital in Mashhad. Cases were children seen in the emergency department with loose watery feces, diagnosed as acute diarrhea by the physician. The controls were selected from the same setting as the cases and included children with traumas, burns, acute respiratory complaints and other diseases.
Results: In univariate logistic regression, variables having a significant relationship with acute diarrhea disease included formula feeding in the first 6 months of life, antibiotic therapy over the preceding 15 days, mother's employment, mother's acquaintance with oral rehydration solutions, place of residence, and disruption in the water supply in the week before illness. We performed multiple logistic regression to examine the role of these variables as independent risk factors for acute diarrhea. Use of formulas before 6 months of age (OR=3.21, 95%CI: 1.77-5.79), and type of residence (OR=1.83, 95%CI: 1.24-2.71), and mother's employment (OR=2.48, 95%CI: 1.2-5.06) were the factors that remained in the multiple logistic model and had a significant relationship with the disease.
Conclusions: This study identified some environmental risk factors for acute diarrhea disease. High-risk groups and mothers of children under 5 years of age should be aware of these risk factors in order to prevent disease in their children. Prevention of acute diarrhea in children can significantly reduce the current burden on the health system.
R Chaman , M Yunesian , B Golestan , K Holakouie Naieni ,
Volume 3, Issue 3 (2-2008)
Abstract
Background and Objectives: A pregnancy can be considered high-risk if there are conditions that put the mother or the baby at higher-than-average risk of morbidity or mortality. Neonatal mortality rate is one of the most important indices of children's health status. The present study was conducted to evaluate the effects of high-risk states on neonatal mortality.
Methods: We performed a nested case-control study in the rural areas of Kohgiluyeh and Boyerahmad province. Within the study cohort, 97 cases and 97 controls were selected by a risk-set sampling method. Data were analyzed with univariate and multivariate conditional logistic regression models.
Results: Neonatal mortality was shown to increase significantly in high-risk pregnancies. There were no substantial differences between crude odds ratios and those adjusted for the presence of other risk factors (crude odds ratio decreased from 5.5 to an adjusted figure of 3.25 for pregnancies with one risk factor and from 5.21 to adjusted level of 4.80 for pregnancies with more than one risk factor).
Conclusions: High-risk pregnancies need great attention in family health and prenatal care programs, especially in remote rural areas. Within our rural health network there are potential cohorts for use in nested case-control studies, especially in the evaluation of neonatal mortality risk factors.
M Qorbani, M Yunesian,
Volume 4, Issue 1 (4-2008)
Abstract
The case-crossover design was developed in the early 1990s to study the effects of transient, short-term exposures on the risk of acute events such as myocardial infarction. To estimate relative risk, the exposure frequency during a period just before outcome onset (hazard period) is compared with exposure frequency during control time(s) in that person rather than in a control. One or more "control times" are supplied by each of the cases themselves to control for confounding by constant characteristics and self-confounding between the trigger's acute and chronic effects.
In the analysis of case-crossover studies, exposure frequency in the hazard period is compared with the control period or the individual's usual frequency of exposure. The design has been used frequently for heart diseases, injuries and air pollution epidemiology. This review article looks at published case-crossover studies and is intended to help the reader gain a better understanding of the strengths and limitations of the case-crossover design in studying the epidemiology of injuries and air pollution.
F Rakhshani, Mt Heidari, S Barati,
Volume 4, Issue 3 (3-2009)
Abstract
Background and Objectives: Injury by sharp instruments and needles are major occupational health hazard for healthcare workers. This study was conducted to determine the prevalence rate and causes of injuries due to needle stick in healthcare workers in Zahedan University of Medical Sciences.
Methods: In a cross-sectional study, 231 healthcare workers of university hospitals of Zahedan University of Medical Sciences were selected at random in 2007. Data were collected through questionnaire and were analyzed by SPSS 13.
Results: From all cases 77.1% were female 56.4% of them were expert, and 50.7% were nurses. Their mean age were 34±8.1 years. Needle stick prevalence was 64.9% during the whole history of career, and 57.2% of them had experiences of needle stick more than twice. Most cases of injuries were related to using needle 55.4%, and they were mostly prone to injury during injection and phlebotomy, 55.6%. The multivariate regression analysis showed that injury due to sharp instruments in university graduates was 60% less compared to those with high school or less, and the injury risk increases 5% in each year of increase in working experience.
Conclusions: The findings of this study highlight the importance of training and preventive measures in healthcare centers particularly among high risk group.
N Esmailnasab, A Afkhamzadeh, A Ebrahimi ,
Volume 6, Issue 1 (6-2010)
Abstract
Background & Objectives: According on surveys in Iran more than two million persons have non insulin diabetes mellitus. There are evidences that good glycemic control reduces the risk of diabetic complications. This study was designed to evaluat the glycemic control by using fasting blood sugar and hemoglobin A1C estimation and their relation with some variables.
Methods: This cross sectional study carried out on 411 people with type 2 diabetes who referred to Tawhid diabetes center in Sanandaj. Demographic and other variables were gathered by a deigned questionnaire. Univariate analysis and multivariate analysis (logistic regression) were used.
Results: In Univariate analysis FBS showed a significant relationship with education, job and referral style and HgA1c was statistically significant with sex, age, education, and job. But logistic regression showed other
Results: in final model FBS and HgA1c were associated with body mass index and referral style and HgA1c had association with only body mass index and referral style. Correlation confidence between FBS and glycated hemoglobin was (r = 0.54).
Conclusions: It is concluded that BMI and referral style have association with diabetes control.
K Holakouie Naieni, A Ostovar, A Danesh, S Sadjedinejad, L Ghalichee, Gh Moradi, Ma Mansournia, Ss Hashemi Nazari,
Volume 6, Issue 2 (9-2010)
Abstract
Background and objective: The nested case-control study has become popular as an efficient alternative to the full-cohort design. This study compares the results of a nested case-control analysis approach with the full cohort analysis.
Methods: A cohort of 276 subjects (new cases from a TB registry) was used for this study. Cox Regression model was used for the full cohort analysis. In order to do the nested case-control analysis, for each death, three random controls were selected from those who did not suffer from the outcome at the time of the outcome took place. Case control data was analyzed by the conditional logistic regression model.
Results: Results from both cohort and nested case-control analyses show that treatment group is the only variable that affects on the outcome. Gender, place of residence, and age has no effect on the outcome. For binary exposure variables with trivial effects (e.g. Gender and place of residence), the relative efficiency of nested case-control study design is approximately 75%.
Conclusion: Results of this study show that nested case-control study is not only an easy and cost-effective method for data analysis but also is as robust as cohort analysis in rate ratio and its variance estimation.
R Rafat, Ar Dorosty, Mr Eshragian, A Rezazadeh,
Volume 7, Issue 3 (12-2011)
Abstract
Background & Objectives: Increasing in prevalence of juvenile myopia in recent decades in eastern and western countries, especially in urban elementary school children, suggests that changing in early life style may play an important role in development of myopia. Our aim was to determine the relationships between myopia and overweight in elementary school children of Eslamshahr a city near Tehran, Iran
Methods: In a case control study, 240 new myopic primary school children (grade 2-4) identified as cases and 240 children without myopia in the same schools enrolled as control group.
Anthropometric information was completed from schools’. Other information about pre-entrancing to school was collected by interviewing their parents. Children having a Body mass index BMI>=85th CDC2000 percentile were identified as overweight. Adjusted odds ratio for overweight was estimated after adjusting other potential risk factors.
Results:
Of total 53.3% were girls. 23.8% of children in case group and 10.1% of them in control group were categorized in overweight group. After adjusting for other potential risk factors (family history, breast milk intake, near works, mother`s job and financial position) being overweight was independently associated to myopia
(OR: 3.10, 95% CI: 1.9-5.03).
Conclusion: It is concluded that overweight in children in preschool age, is independently associated with increased risk of myopia in primary school children. Therefore health promotion programs in order to change of the life style in this group of children should be considered.
M Mohammady, N Toghian Chaharsougi , S Abdoli,
Volume 9, Issue 3 (2-2014)
Abstract
Background & Objectives: Randomized controlled trials are the most reliable type of study to be able to compare different interventions in scientific research. The introduction of bias into the design and conduct of randomized controlled trials can seriously affect the accuracy of the results and led to the results be invalid. The aim of this study was to assess the bias in randomized controlled trials published in Iranian nursing and midwifery journals.
Methods: We searched all published articles in eight professional nursing and midwifery Iranian journals in 2010. Risk of bias in RCTs was assessed using of Cochrane group risk of bias standard tool by two reviewers independently.
Results: After reviewing the eight journals, 68 randomized controlled trials were retrieved. The majority of studies had unclear or high risk of bias. Random sequence generation in 22%, concealment allocation in 4.5%, blinding in 22%, incomplete outcome data in the 35.3%, selective outcome reporting in 51.5%, and other bias in 36.7% of the studies were in low risk of bias.
Conclusion: A large proportion of the studies had high or unclear risk of bias. It was considerable that none reporting bias led to uncertainty reader from study quality. Bias might significantly affect the internal validity of the studies results therefore in interpretation of the findings of these studies caution should be taken.
H Akbarein, Ar Bahonar, S Bokaie, N Mosavar, A Rahimi- Foroushani , H Sharifi, As Makenali, Nd Rokni, B Marhamati- Khameneh , S Broumanfar,
Volume 10, Issue 3 (12-2014)
Abstract
Background & Objectives: Bovine Tuberculosis (BTB) is one of the most important zoonoses. Mycobacterium bovis is the responsible agent of BTB in the cattle. The current study was conducted to investigate the determination factors of BTB in dairy farms covered by the tuberculin screening test.
Methods: A herd level case- control study was carried out in 124 (62 cases & 62 controls) dairy farms in the provinces of Tehran, Alborz, Hamedan, Isfahan, Qazvin, Qom, Mazandaran and Semnan. The control farms were individually matched with case farms by farm capacity and distance. Statistical analyses were done by Stata 11.2 using conditional logistic regression.
Results: Proper management of manure (OR=0.12 95% CI: 0.03-0.49), regular flaming of stalls (OR= 0.21 95% CI: 0.04-0.92) and complete fencing around the farm (OR= 0.17 95% CI: 0.03-0.81) decreased while the presence of rodents (rat) (OR= 4.90 95% CI: 1.04-23.01) increased the risk of infection. The interaction among these variables was not statistically significant
Conclusion: According to the results, there is an essential need to pay more attention to rodent control in farms.
F Moghaddas, F Yousefi , F Bagheri, M Mohammadi , F Mahdian Arefi , A Beikmohammadi, Mh Emamian,
Volume 11, Issue 2 (9-2015)
Abstract
Background & Objectives: Urinary calculi are a common problem worldwide. The pattern of fluid consumption in healthy people and patients with renal calculi is not totally clear. The aim of this study was to determine the association between the amount of fluids intake and urinary calculi.
Methods: In this case-control study, cases were the patients with urinary calculi admitted to Emam-Hossein Hospital, Shahroud, Iran. The controls were selected among the patients admitted to other wards of the hospital except for dialysis and ICU wards. The association between independent variables and urinary calculi was investigated using logistic regression analysis.
Results: A total of 127 people (60 cases and 67 controls) participated in this study. The mean age of the participants was 44.6 years (SD = 1.7). The mean intake of tea, natural juice, alcohol free beer, and total fluid intake were higher in cases compare to controls. In participants with a negative history of urinary calculi, the total intake of fluid (P=0.021) and natural juice (P=0.006) was higher in cases. The male gender (OR=3.2), higher BMI (OR=1.2), and a positive family history of urinary calculi (OR=3.5) were associated with renal calculi in a multivariate logistic regression model, while the milk intake (OR=0.995) was a protective factor in this model.
Conclusion: Milk intake is a protective factor and the male gender, higher BMI and a positive family history are the risk factors for urinary calculi.
V Montazeri, F Jafarpour Sadegh , S Hosseinpour, Hr Mirzaei, E Akbari, M Ehsani, S Akbari, N Asadi, M Mahmoudinezhad, E Mirtaheri, Z Sanaat, S Pirouzpanah,
Volume 12, Issue 1 (6-2016)
Abstract
Background and Objectives: Reproductive factors are in close relationship with breast carcinogenesis. This matched case-control study was conducted to study the association of reproductive risk factors with the risk of breast cancer (BC) among women in Tehran and northwest of Iran.
Methods: This hospital-based case-control study was performed on a total of 432 patients diagnosed with BC with confirmed histopathology who were recruited from hospitals affiliated with Shahid Beheshti and Tabriz University of Medical Sciences between 2007 and 2012, and 543 regionally matched controls without a prior history of BC.
Results: The average number of pregnancy and breast-fed children were significantly higher in cases than controls (P<0.01). The duration of breast-feeding was longer in patients (18.0±8.4 months) than controls (16.0±9.1; P<0.001). Most of the patients were diagnosed with BC above the age of 48 years old which was higher than the mean age of the recruited matched controls. Older age was associated with a 3.87 higher risks of BC development (95% CI: 2.94-5.10). The higher frequency of lactation in patients was significantly associated with the elevated risk (OR=2.22, 95% CI 1.62-3.04). The duration of breast-feeding within14-24 months was correlated with OR=0.52 to protect BC development during the reproductive age
(<48 years) (95% CI: 0.32-0.86).
Conclusion: High frequency of pregnancy, lactation, and older ages at first pregnancy are associated with the risk of BC, while older age at puberty, menopause, and longer duration of breast-feeding (age above 48 years) have inverse associations with the risk of BC.
F Bagheri Amiri , Ar Bahonar, E Mostafavi, Ma Mansournia, N Rasouli , Mh Fallah Mehrabadi, D Abdollahi, Sholepash,
Volume 12, Issue 1 (6-2016)
Abstract
Background and Objectives: Foot-and-mouth disease (FMD) is one of major contagious animal. The purpose of this study was to evaluate the determinants associated with FMD occurrence in farms.
Methods: A case- control study was carried out in cattle farms. The cases were farms with new reports of FMD and controls were units without any report of FMD in last 6 month. For assessing the risk factors, a researcher- made questionnaire was used. Statistical analyses were done with SPSS version 16 using the logistic regression test.
Results: Purchase of new livestock [OR: 14.69 (CI95%: 4.29, 50.36)] and passing migratory livestock [OR: 13.32 (CI 95%: 1.74, 101.87) were identified as the risk factors of the disease. Visiting the farm by the vaccinator in last 2 weeks [OR: 0.17 (CI 95%: 0.05, 0.63)] and buying new livestock from the same village/ city where the farm is located [OR: 0.16 (CI 95%: 0.04, 0.58)] were considered as protective factors.
Conclusion: Considering the role of infected livestock in the country, the most important steps for effective preventation are: areadherence to biosecurity as well as quarantining new purchased animals, and informing and training farmers to not purchase new animals from farms that are located in the infected areas and around the times of outbreak.
K Holakouie Naieni , Ma Mansournia, Mh Panahi, A Elduma, Sh Nematollahi ,
Volume 12, Issue 3 (10-2016)
Abstract
Case-Cohort and nested case-control designs are the most well-known and cost-effective derivatives of prospective studies. Due to the popularity of these designs in recent years, the aim of this study is to provide a comprehensive and up-to-date description of them with respect to methodological issues such as sampling scheme, effect measure estimation, and analysis strategies. Overall, random sampling of controls in case-cohort and matching for time in nested design are considered their hallmarks. Eventually, decision on a better design depends on study objectives, sub-cohort selection, case and control determination, and method of data collection. It should be kept in mind that any particular study requires unique elaboration and delicate examination to choose from the designs.
Z Torabi, Sh Nematollahi, E Ahmadnezhad, K Holakoie Naieni ,
Volume 14, Issue 2 (9-2018)
Abstract
Background and Objectives: Epidemics of diarrhea caused by contaminated food and water occur frequently worldwide, especially in developing countries. The aim of this study was to identify the factors contributing to the development and spread of diarrhea epidemics caused by Shigella flexneri in Isfahan in the spring of 2015.
Methods: Following the first reports and activation of the surveillance system, a matched case-control study was conducted in 360 cases with diarrhea and 360 controls. Data were gathered using a questionnaire, and conditional logistic regression was used to provide adjusted odds ratios and 95% confidence intervals.
Results: Consumption of contaminated fresh vegetable (OR=4.50, 95% CI=2.88-7.01) was the source of the epidemic. Contact with similar patients (OR=7.19, 95% CI=4.26-12.12), presence of similar patients in the family (OR=33.2, 95% CI=13.64-80.82), food consumption on special events (party, wedding ceremony, funeral, etc.) (OR=1.67, 95% CI=1.06-2.62), being a government employee (OR=3.08, 95% CI=1.64-5.78) and being illiterate (OR=2.91, 95% CI=1.10-7.67) were the risk factors of the spread of the epidemic.
Conclusion: In this study, consumption of fresh vegetable contaminated with Shigella flexneri was the source of the infection. According to the Epidemic Management Team, contamination occurred due to non-standard wastewater irrigation of agricultural lands. Therefore, it is important to consider the standards of agricultural production and compilation of a comprehensive program to improve the status of the wastewater purification system in the environmental sciences by the relevant organizations to prevent diarrhea epidemics.
B Moatamedizadeh, H Ansari, A Payandeh, Sm Tabatabae, A Ramazanpouramirdehi,
Volume 16, Issue 1 (6-2020)
Abstract
Background and Objectives: In addition to effective treatment, tuberculosis recurrence is a very important challenge regarding the treatment of this infection. This study was conducted to evaluate the risk factors associated with tuberculosis recurrence.
Methods: In this nested case-control study, 202 tuberculosis patients with recurrence and 202 matched controls in terms of age, sex and place of residence were studied. The cases and controls were selected from a cohort of tuberculosis patients in Sistan and Baluchestan province between 2011 and 2018. The data were collected using interviews and patients’ records. The independent t-test, chi-square and multiple conditional logistic regression were used to analyze the data.
Results: The drug abuse history (OR=6.1), 3+ smear positive (OR=3.03), chest X-ray suggestive of tuberculosis (OR=4.9), drug resistance (OR=7.3), low socioeconomic status (OR=3.9), weight loss (OR=3.1), chest pain (OR=3.2), history of digestive disease (OR=22.1), smoking (OR=6.1), and imprisonment (OR=3.7) significantly increased the chance of recurrence among tuberculosis patients (p<0.05). On the other hand, the chance of recurrence was significantly lower in patients with coughs (OR=0.29) and a small family size (OR=0.28).
Conclusion: According to the results, tobacco use, drug use, low socio-economic status, life conditions, and disease conditions are the most important determinants of tuberculosis recurrence. In general, epidemiologic factors related to tuberculosis recurrence are not similar in different regions; therefore, educational programs for patients and their families and prevention methods should be considered based on related factors in different regions.
M Karami, A Doosty Irani, Sj Battaei, L Rafati, M Javaheri, M Kheir Andish , M Farhadi, M Hashemi, K Mozafari, A Akhlagh, M Shojaeian, Ar Maleki, R Rostam Abadi , Sh Torkshavand, M Khodabakhshi,
Volume 16, Issue 3 (11-2020)
Abstract
Background and Objectives: Water and foodborne diseases are major causes of mortality worldwide. The aim of this study was to investigate the factors affecting an gastroenteritis outbreak in Hamadan county in summer of 2019.
Methods: This study was performed based on the outbreak investigation process. After producing hypotheses based on preliminary field studies, a case-control study was conducted on 45 cases and 45 controls to investigate the factors associated with the outbreak. New cases of the disease were included according to the case definition. A logistic regression model was used to investigate potential risk factors.
Results: A total of 171 people were affected in this outbreak from 25 June 2019 to 01 July 2019. The at-risk population in this outbreak was 3410 individuals. The attack rate was 5.1%. Abdominal pain, vomiting, and nausea were the most common symptoms with a prevalence of 77.8%, 73.3% and 68.9%, respectively. The results of the case-control study showed that the consumption of tap and spring/well water increased the odds of disease by 4.63 and 4.13 times compared to boiled water, although these relationships were not statistically significant. The odds of diseases were significantly lower in people aged 30-45 years and 46-85 years compared people aged 15 years old and younger.
Conclusion: Based on the results of this study, the outbreak was related to contaminated water consumption. Therefore, regular monitoring of drinking water status is very important for the local health system.
