Iranian Journal of Epidemiology
Year:2011 | Volume:6 | Issue:4|Papers Count:9

Background and objective: Participation of community-based services in the National Tuberculosis Control Programme is (NTCP) necessary to identify and treat all patients with tuberculosis (TB). We developed a novel model to encourage family members and relative to participate in the RNTCP in Darahshar city.Methods: This community-based intervention was included of two groups of community (relatives of patients and schools). They were trained to identify and refer of patients to allocated health centers. Case finding indices were compared initially and one year intervention. The exponential distribution and logarithmic of incidence were used to compare the incidence of tuberculosis after the intervention with other cities of the province.Results: The incidence of smear positive cases increased from 5.1/100,000 to 35.2/100,000 (p<001). There was a statistically significant difference between incidence of smear positive cases in Darehshar city and other cities in Ilam province (p<001). During the intervention, 408 suspected patients was identified, it showed about 297 percent increase in case finding (cases in the previous year of the intervention were 137 cases) (p<001).Conclusion: It seems that community-based intervention could be an effective method to enhance of identify and control of patients with tuberculosis.

Background & Objective: the number of people with HIV/AIDS in Iran is increasing. Populations' knowledge and awareness are crucial steps to prevent HIV/AIDS epidemic. This systematic review aimed to assess the level of knowledge and attitude toward HIV/AIDS in Iranian population.Methods: Reviewing related titles in national and international databanks resulted in 62 eligible studies published between 1998 and 2008. To explore the source (s) of heterogeneity, meta-regression model was used.Results: Due to the methodological diversity of included studies (e.g. their sampling or data collection methods) pooled estimation of the results were hard to be applied. The mean for knowledge score among 24 eligible studies (including 24,011 individuals) varied between 14.7 and 84.0 out of 100. Among those 16 eligible studies (including 11,104 individuals), the reported mean for attitude varied between 32.6 and 78.4 out of 100.Conclusion: In overall, it seems that the knowledge and attitude in Iranian population still need to be improved; however, the results from our systematic review showed a considerable heterogeneity among the results that can be originated from the diversity of target populations and/or their methodology of included studies. Planning for further targeted programs and modifying public education for more effective schemes are necessary to be emphasized, as there was not a significant change in the level of knowledge or attitude based on the included studies.

Background & Objectives: Proceed model is widely used in health promoting program. The aim of this study was to investigate the effect of PRECEDE Model– based educational program on nutritional behaviors in a rural society.Methods: This study was a quasi-experimental (before– after) study and conducted on one hundred eighteen women in eight rural areas in Fridan. Based on precede model, CHD mortality rate, incorrect nutritional habits and nutritional behaviors were identified as the most important indicators. During educational intervention, predisposing factors, enabling factors and reinforcement factors were noticed. The training content was designed based on precede model contains 3 educational sessions weekly for 2 months.Results: Following the educational intervention, the mean score of knowledge, attitude was significantly increased and predisposing, Enabling and Reinforcing factors as well as behavior were improved. Approximately nine percent of participants perceived they are at risk of heart diseases and 12.96% believed that their regimes are not healthy (bad). Near 48% indicated that heart diseases are preventable diseases.Conclusion: The finding of current study confirmed the practicability and effectiveness of the PRECEDE Model –based educational program on Behavioral.

Background & Objective: Mixed outcomes arise when, in a multivariate model, response variables measured on different scales such as binary and continuous. Artificial neural networks (ANN) can be used for modeling in situations where classic models have restricted application when some of their assumptions are not met. In this paper, we propose a method based on ANNs for modeling mixed binary and continuous outcomes.Methods: Univariate and bivariate models were evaluated based on two different sets of simulated data. The scaled conjugate gradient (SCG) algorithm was used for optimization. To end the algorithm and finding optimum number of iteration and learning coefficient, mean squared error (MSE) was computed. Predictive accuracy rate criterion was employed for selection of appropriate model. We also used our model in medical data for joint prediction of metabolic syndrome (binary) and HOMA-IR (continues) in Tehran Lipid and Glucose Study (TLGS). The codes were written in R 2.9.0 and MATLAB 7.6.Results: The predictive accuracy for univariate and bivariate models based on simulated dataset Ι, where two outcomes associated with a common covariate, were shown to be approximately similar. However, in simulated dataset ΙΙ in which two outcomes associated with different covariates, predictive accuracy in bivariate models were seen to be larger than that of univariate models.Conclusions: It is indicated that the predictive accuracy gain is higher in bivariate model, when the outcomes share a different set of covariates with higher level of correlation between the outcomes.

Background & objectives: Competing risk data is one of the multivarite survival data. Competing risk data can be modelled using copula function. In this study we propose a bayesian modelling approach of competing risk data using the copula function.Methods: We used the data from colorectal cancer registyrarty in Tehran. After constructing likelihood function using Clayton copula by choosing appropriate prior distribution for parameters, we obtained the posterior distribution of parameters using the Metropolis-Hastings algorithms and Slice sampling.Results: The results of univariate analysis showed that sex, histology of tumor, extent of wall penetration, lymph node metastasis, distant metastasis and pathological stage of tumor were significantly associated with colon cancer and sex, histology of tumor, lymph node metastasis, distant metastasis and pathological stage of tumor were significantly related to rectal cancer. In the multivariate analysis, age at diagnosis, tumor grade and distant metastasis were significant prognostic factors for colon cancer and tumor grade and size of the tumor were significant prognostic factors of rectal cancer.Conclusions: As we showed some variables may have different impacts on colon and rectum cancers, consequently, further studies are needed to be conducted considering risk factors of these cancers separately.

Background & Objectives: To determine the prevalence rates of refractive errors in Mashhad, Iran.Methods: In this population-based study, random cluster sampling was performed on the urban population of Mashhad and of 4453 selected individuals, 70.4% participated in the study. Refractive errors were assessed using cycloplegic refraction in participants who were £15 years of age and non-cycloplegic refraction in those who were >15 years of age.Results: The prevalence of myopia and hyperopia in individuals £15 years old was 3.64% (95% CI: 5.09 to 2.19) and 27.4% (95% CI: 31.09 to 23.72), respectively. The same measurements for individuals >15 years of age was 22.36% (95% CI: 24.66 to 20.06) and 34.21% (95 CI: 36.85 to 31.57), respectively. The prevalence of astigmatism and anisometropia were 25.64% and 5.84, respectively. Astigmatism and anisometropia were significantly more (p=0.005) and less (p=0.048) prevalent in females, respectively. Anisometropia, astigmatism and hyperopia were found to be increased with age.Conclusions: This study highlighted the valuable information on refractive errors in Mashhad. Hyperopia was the most common refractive error. In addition to subjects who were between 5 to 15 years of age, refractive errors were also prevalent among older people; therefore, more attention should be paid to the correction of refractive errors in these groups.

Background & objectives: Head injuries are the most sever kind of injuries in accidents. It is an important factor of disability in society. Having information about present situation and its determinant factors is the first step of programming for head injury reduction. This survey aimed to have an epidemiological aspect of head injury in Arak.Methods: Relevant information about severity of the impact, causes, demographic information and treatment results were extracted from medical files between 2005-2006 years.Results: Of total 1105 patients with head injury 25.8% were in their first decade of life and 11.8% were reported as severe head injury. The most common injuries (18.4%) caused by downfall from low height. Men had more headed injured 64.7% compared with women. In the period of hospitalization 12.8% of moderate head injuries and 43.1 of severe head injury caused to death.Conclusions: It is concluded that applying and administration of the safety rules in the society as a compulsory rules and educating by mass media, are necessary. It should also be taken into account more effective hospital care for severe head injuries to reach better outcomes.

Background & objectives: Content validity is the first type of validity that has to be ensured during the design of a tool. Its prerequisite for other validities and its close relationship with the tool reliability place it in a vital position in the questionnaire design. However, since it has not been paid enough attention in national publications therefore in this paper we will explain the different steps in preparing an appropriate content for questionnaires and also their assessment.Methods: The steps of the content validation process for designing valid and reliable questionnaires have been explained in this paper: development (domain identification, items generation and instrument construction), Judgment – quantification (determining the inter rater agreement among experts, determining the clarity and relevancy of each of the questions along with the clarity, relevancy and comprehensiveness of the tool as a whole) have been explained.Conclusions: The benefits of performing the content validation in questionnaire development are not increasing the possibility of accessing desirable content validity indexes (relevancy, clarity, and comprehensiveness) only, but also improving the Reliability indexes of tool and decreasing need for resources (financial and temporal) are the other benefits of this approach. Although subjective nature of experts’ responses is the problematic issue in this process but the more quantitative steps of the content validation has reduced considerable part of previous worries about this process. These issues explain why content validation has become a suitable process for questionnaire.