Journal of School of Public Health and

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Approximately 21% of children and adolescents experience signs and symptoms of aDSM-1V disorder during the course of a school year, yet fewer than 20% of those needingmental health services actually receive any. Research suggests that schools and teacherscan help promote mental health, delect children at risk, and refer them for psychiatricassistance. This study aims to determine the effects of an educational intervention onteachers' knowledge, attitude, self-reliance and practice.This study was carried out in 24 State-run elementary schools in the city of Khorramabadin Lorestan province. Iran, during the academic years 2001 - 3.Of the 64 teachers initially selected, 57 agreed to participate in the study 27 of these wereplaced in the intervention group and the remaining 30 in the control group.The intervention group attended a 3-day workshop. Self- administered questionnaireswere filled before and after the workshop, and at the end of the project data were collectedfrom teachers and students. Statistical analysis was done by the SPSS package, usingmainly nonparametric tests.49% of the participants were men, 42% had a high school diploma and others haduniversity degrees. Findings showed significant improvements in teachers' knowledge.attitude, and practice in the intervention group. Nosuchimprovement was observed incontrols. Teachers in the intervention group were able to identify and refer 106 suspectedcases, of whom 79 had a mental disorder confirmed by a psychiatrist. Within the sameperiod, only 2 cases had been referred by the control group. Students' knowledge, themain criteria of teachers' practice in mental health education, had significantly improvedin the intervention but not in the control group. Results suggest that female teachers hadhigher KAP levels than their male colleagues.The study confirms that trained teachers have the capabilities required for participating inSchool - Based Mental Health Services. It also appears that schools are indeed a crucialplace for helping children in need of mental health services.

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Toxoplasmosis is a common disease caused by the protozoal parasite Toxoplasma gondii. Most human cases occur by 1) eating raw or undercooked meat containing T. gondii tissue cysts. 2) ingestion of oocysts from soil and 3) vertical transmission through the placenta. Immunocompetent adults are usually asymptomatic or present with self-limited fever and lymphadenopathy. Infection acquired during pregnancy can be transmitted to the fetus and may cause mental retardation, blindness, epilepsy, and abortion. In this cross-sectional study we determined the prevalence of toxoplasma infection in residents of Meshkin-Shahr in 2001-2002. We applied a cluster sampling method to family health files in local health centers to recruit a total of 909 individuals for this study. All family members were requested to complete the study&aposs questionnaire. For each individual, two separate blood samples were collected and placed in microhematocrite tubes. Titers of anti-toxoplasma antibodies were measured by IFA with levels in excess of 1/20 taken as positive. Questionnaire information and examination results were analyzed by the SPSS software package using chi-square tests. Results of this survey show the overall prevalence of toxoplasma infection to be around 18.3%. Figures for men and women were 19.7% and 17.2%, respectively but the difference was not statistically significant. Prevalence rates show a significant association with age (greater prevalence in higher age groups) and the type of meat consumed (P<0.05). But there were no significant associations with education level, occupation-keeping cats in the house, ingestion of meat and history of previous abortions. The most frequently occurring antibody titer was 1/20 (6.9%). and frequency decreased with higher antibody titers.
This study shows that toxoplasma infection is not as common in Meshkin-Shahr as in some parts of the country, with more than 80% of individuals being seronegative. Because of the low immunity level and the risk of vertical transmission, educating the public in prevention methods could be very important.

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Misclassification of disease status and risk factors is one of the main sources of error in studies. Wrong assignment of individuals into exposed and non-exposed groups may seriously distort the results in case-control studies. This study investigates the effect of misclassification error on odds ratio estimates and attempts to introduce a correction method. Data on 3332 men aged 30-69 years from Tehran Lipid and Glucose Study (TLGS) were considered for investigating the relationship between angina pectoris and smoking. The “Rose” questionnaire was used to evaluate angina status. Two different definitions of smoking were included: I) active smokers versus non-smokers, II) active and ex-smokers versus never smoked. The relation between variables was assessed both with and without considering misclassification in smoking. Definition I (commonly used in many epidemiologic studies), resulted in a non-significant OR=1.09 (95% CI: 0.84, 1.41). Using the correction method based on the principle of non-differential misclassification, the OR increased to 1.13 (95% CI: 0.89, 1.43), which was still non-significant. However, a correction procedure that included the probability of differential misclassification produced a significant OR=1.46 (95% CI: 1.15, 1.85), p<0.05. It is evident that misclassification in risk factors can lead to inaccurate results. This study showed that the relation between variables may have not been discovered if the probability of misclassification was ignored. Moreover, in case of probable differential misclassification, applying correction methods for non-differential misclassification would be inefficient.

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In large–scale sampling opeartions (e.g. nation-wide health surveys) we always face the problem of non-response item(s) and/or non-response unit(s). In fitting a model to the data we have two groups of variables, namely dependent and independent variables. Non-response may occur for any of these groups of variables. In this paper we assume Y as a categorical dependent variable with three levels, Z and X as independent variables from any kind: scale, categorical, ordinal, etc. We have complete data on the first two variables and we assume that the missing items follow a random pattern (MAR). Then a model is devised based on the likelihood function for the whole data set (including missing values) and estimates of parameters are compared with those obtained by statistical programs such as SPSS, which are only based on completely observed data and ignore units with missing data. Our results show that the likelihood-based model is superior to the standard approach utilized by the software packages. The comparison is made using data on thyriod disease (goiter) obtained by a health survey in Gazvin province.

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There are about 200,000 injecting drug users (IDUs) in Iran. HIV/AIDS is closely associated with IDU in Iran. The objective of this study was to explore unhealthy sex behavior and the interventions for its control in IDUs.
A qualitative method was employed. Six districts in Tehran with a population of 400,000 were selected. These districts differed in socioeconomic characteristics, urban structure, IDU prevalence and crime rates. A total of 81 key informants from different sectors and 154 IDUs were selected by purposeful, opportunistic and snowball sampling, and interviewed individually or in groups. Ethnographic observations were done to study life situation in the subjects.
In one district no cases of IDU were found. In others, sexual promiscuity in IDUs was reported to be common. IDUs report sexual relationship to be more common with sex wrkers. In most of these areas, access to commercial sex is believed to be easy. Sex workers, themselves are commonly drug users, half of them are actually IDUs. Safe sex (e.g., use of condoms) is not a common habit. Homosexual relationship seems to be uncommon in IDUs and there were no reports of condom use in this type of contact. According to IDUs, dealing with this problem would require financial support and drug distribution for preventing sex work, and settlement and organization of sex workers as a prelude to effective sex education and promotion of condoms.
Expansion of injecting drug use and its relationship with blood-borne infections in recent years necessitates rapid interventions for controlling injection drug use and the associated risks. As unhealthy sex behavior seems to be common in IDUs, sex education, free condom distribution in drug abuse treatment centers and other health facilities (with the use of outreach methods) is highly recommended.

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This study is a retrospective review of the epidemiology of kala-azar, using cases reported to health facilities in Ardebil province over a period of 5 years: from the beginning of 1997 until the end of 2001.
The total number of cases was 602, but as the assessment was only possible in hospitalized patients, the questionnaires were completed for 293 cases with detailed records in 5 hospitals (3 in Ardebil and two in Meshkin-shahr and Germi). Another 76 cases were also excluded (due to incomplete records) and in the end 217 questionnaires were analyzed by the Epi-info 2002 package.
Compared to the total number of cases (1051) reported in a similar study over the years 1985-90, the reduction in total number of cases (602) may be due to reduced incidence rate in Meshkin-Shahr and/or underreporting. Although the total number is down, the number of new cases in Germi and Bilehsavar districts has increased. In our study the overall male to female ratio was 1.4 to 1 this ratio was 1.5 to 1 in hospitalized patients. 74% (160) of cases were under 2 years of age and 93% (201) under 5. Only 1.8% (4) of patients were over the age of 10 years. Though the majority of the patients were seen in Ardabil city, most had been referred from Germi district. 87.5% were village dwellers, mostly referred on cold months of the year the number of referrals was lowest during summer. The most frequently used diagnostic test (especially in recent years) was DAT, positive in 77% of tested cases (titers/1600). We also performed BMA on 30 patients, of which 87% (26) were positive. 58%) of the subjects had been diagnosed in about a month after the disease onset and 93% within 4 months. The most common clinical features were anemia, fever, anorexia, splenomegaly (all present in >90% of cases) other manifestations were malnutrition, cough, hepatomegaly, diarrhea, vomiting, Iymphadenopathy, hemorrhage, jaundice, edema and ascitis. In 6 cases (3%) the chief complaint was febrile convulsion. The most common laboratory findings were anemia (mean Hb - 8.96 mg/dl), elevated ESR (highest level being 140mm/l hour), thrombocytopenia and neutropenia. Liver enzymes were elevated in one third of the patients. 96% of the cases treated with Glucantime the remaining 4% were relapse cases or treatment failures and had been given Amphotricin-B. 95.8% (211 cases) had been discharged in good general condition 3% (6) had died. The exact causes of death were not mentioned in hospital records.
According to these findings, Kala-azar is a major health problem in Ardebil province, especially within the rural population and specifically in Germi and Bilehsavar districts. It requires more intense control and more medical facilities alongside education programs for health workers and general population.

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Measuring of service quality is the basic prerequisite for improving quality. Patients&apos expectations and perceptions of service quality play an important role in the choice of hospital, loyalty to organization and behavioral intention. A first step towards improvement would be to determine areas of quality that are most defective. Studies show that consumers are in close contact with service providers, and they are involved in the service process. Therefore, this group can measure services quality better than any other group. This study was conducted to measure service quality based on patients&apos expectations and perceptions in Zanjan hospitals.
The cross-sectional design was used in this research. For data collection, SERVQUAL questionnaire was employed. To ensure the reliability of the questionnaire, the internal consistency reliability test (Cronbach alpha) was performed.
Findings: Cronbach alpha for service quality was .94. Results show that the assurance (knowledge, experience and ability to maintain patients&apos confidence and trust) was rated as the most important dimension. (SQ mean = -1.3). There were differences between patients&apos expectations and perceptions in all the dimensions.
the assurance dimension constitutes the most serious problem facing hospitals. It is recommended that physicians thoroughly explain the disease condition to patients, and that patients should be treated with dignity and respect.

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This cross- sectional study was done to assess the prevalence of chronic cough by age and date of birth (age-period-cohort analysis). Using data from two National Health Surveys in 1991 and 1999 (involving cross-sectional general population samples), we studied all cases of chronic cough recorded during the period of 1991 to 1999 in people aged 2 to 70 years. A birth cohort analysis was performed on the data. Comparison with earlier surveys showed that the prevalence of chronic cough had fallen from 4.5% to 1.8%. Age-period-cohort analyses of the age effect revealed that prevalence rate of chronic cough increased with age but in every age group it actually decreased after the 8-year period. The fact that different trends are observed in cross-sectional and cohort data points to a strong cohort effect. the prevalence of chronic cough is strongly determined by a person’s year of birth. Also for any given age group, prevalence rates were lower in younger compared to older cohorts.

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Awareness regarding incidence pattern of disease is an important issue for researchers. To explore seasonal pattern of TB in Iran we decided to do this study. This study have been done as an ecologic study .all notified TB cases during 1997 to 2001 have been included in this study .all data have been processed and analyzed by the Cosinor analysis method. We found 59756 registered TB cases during above mentioned years. TB in this 5 year period has seasonal pattern (amplitude=11.73% ,acrophase=13 June(85.23) , p<0.000) . Frequency of TB cases evaluated by sex in this model and found that there is seasonality by sex too (p<0.000) , but different amplitudes found for female and male(13.35%, 10.5%) and point estimate of acrophase for them were consequently 18 June and 8 June . When we evaluate this pattern among smear positive and smear negative cases found that smear positives have seasonal pattern (p<0.000) . Association of TB frequencies in quarters and mean temperature of each quarter have been evaluated by ANOVA in different 4 temperature groups(p< 0.020) ,and a significant difference have been found between 10-20 and 20-30 temperature groups(p<0.051) . According to this study there is a seasonal pattern in TB notification (incidence) in Iran which should be notified in population based studies and surveys in this regards. Comments: We recommend performing more studies on patterns of pulmonary disease, other relevant factors on TB involvement and also laboratory circulation to clarifying cause of existing seasonality

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The aims of the present study were to assess preparedness and function of health system in the management of withdrawal symptoms in opioid dependents after Bam earthquake, the methods that medical staff used for identification of dependents, the viewpoints of the medical staff as well as opioid dependents about the roles of health system, and the appropriate methods for managing opioid dependence after disaster. This qualitative study was carried out in the city of Bam, one of its nearby villages and eight hospitals in Tehran and Kerman, admitting earthquake victims. Our analysis was based on 163 semi-structured interviews, with drug abusers, their family members, people living in Bam, service providers, and the authorities. No specific training for drug abuse was reported by medical staff. No guideline or program was available for prevention and management of drug dependence in disasters. Most of the medical staff had negative attitudes toward involvement in treatment of opioid dependence. During the first two weeks after the earthquake, medical management of the withdrawal symptoms was inadequate. Most of the interviewees suggested managing the withdrawal symptoms with prescribing opioid agonists and then treating the opioid dependence following improvement of physical injuries and stability of social situation. In disaster situations, the consequences of inadequate management of opioid dependence can be ominous. Such consequences consist of a change in incidence of substance use, intensity of use and dependence, type of substance and route of use to more dangerous ways. Therefore, a practical protocol (disaster planning) is needed for prevention and management of substance dependence in the times of crises.

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Diabetes is a chronic disease of lifelong duration, and its management requires a fundamental change in the patient’s lifestyle. The aim of this study was to evaluate the efficacy of a health education program on the knowledge, behavior, HBA1c and health related quality of life of diabetic patients after following the patients’ participation in the program. The study population consisted of type 2 diabetic patients attending at Bandar Abbas diabetic clinic. Eighty patients were randomly selected and they were randomly assigned to two groups, 40 to the intervention and 40 to the control group. At the initial visit and 4 months after education, knowledge and behavior were assessed by questionnaire HBA1c measured by colorimetric method and health-related quality of life assessed by means of WHOQOL-BREF questionnaire. The education sessions for intervention group were held at diabetic clinic. The 40 patients that assigned to the control group gave the appropriate consent and completed questionnaires at baseline and after 4 months. The intervention group had statistically significant increase in the mean of knowledge score from 6.7 to 15.8(p=0.000), physical health from 64.7 to 77.2 (p=0.000) and psychological health from 56 to 71.4(p=0.000) and had statistically significant reduction in the mean of HBA1c from 9.4 to 8.2 (p= 0.000).Also the intervention group had statistically significant increase in self-monitoring blood glucose, weight monitoring, exercise and diet. Patients in control group showed no significant changes in the outcomes measured except for knowledge.

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In recent years the patterns of mortality have changed in Iran, and cancers are playing a greater role in this regard in this country. Various reports indicate that gastric cancer is highly prevalent it is the second most common cancer in men, and fourth in the general population. The purpose of this study was to determine the five-year survival rate of gastric cancer patients who had undergone surgical treatment at one of the most important cancer treatment centers, the Iran Cancer Institute, and to assess its associated factors. Three hundred and 30 patients with gastric cancer who had been admitted to and operated on at the Iran Cancer Institute between January 1996 and April 2000 were enrolled in this study. The patients’ life expectancy after surgery was determined, and its relationship with variables of age at the time of surgery, gender, and factors related to the disease such as the cancer site, pathologic type, stage, presence of metastasis, and sites of metastases were assessed. The five-year survival rate and the median life expectancy in the studied patients were 23.6% and 19.90 months, respectively. Univariate analysis showed that gender, cancer site, and pathologic type did not affect life expectancy significantly. But the five-year survival rate significantly decreases with age. As expected, those involved with metastasis had a significantly lower five-year survival rate, and the disease stage significantly affected the patients’ life expectancy (P<0.001). The Cox proportional hazards model was used to assess the effect of different variables simultaneously, and it showed that age, distance metastasis, and disease stage influenced the rate of survival. Gastric cancer patients in Iran have a low five-year survival rate. One of the most important reasons seems to be delayed consultation and diagnosis. Most patients are seen first with the disease in the late stages. At this point, most have lymph node and liver metastasis which makes treatment even more complex. Thus, it is necessary to employ mass media for extensive public education about the early warning signs of the disease and performing periodic examinations.

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Background and Aim: In order to elucidate the role of vitamin D in the genesis of lung tumors, we used an experimental model of lung lesions in mice induced by the administration of urethane.
Materials and Methods: A total of inbred balb/c mice (male and female) 9-11 weeks old, were studied. They were divided into 3 groups. The first and second groups (U and U+D) were injected with urethane i.p, 600 mg/kg/day with 48 hours intervals for three times. The second group was given 3.5 mg/kg (6.3 mg/1000 ml) vitamin D with drinking water for 4 weeks after starting the injection by urethane.
Results: The third group served as control. Total remaining mice were killed after 20 weeks. Lung lesions were histopathologically characterized by hyperplasia, adenoma and adenocarcinoma in different groups. Tumor formation significantly increased in the urethane group as compared with control group (p<0.05) but there was not any difference between those receiving the (U+D) treatment group and the controls.
Conclusion: It seems vitamin D inhibites genesis of lung tamors induced by the administration of urethane.

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Background and Aim: Looking at population pyramid from the 1996 census and its estimates for the years 2003 and 2004, it is clear that the size of the elderly population will be greater in men than in women. According to Iran’s Ministry of Health, the life expectancy for women is greater than that for men. This article is devoted to the discussion and analysis of this paradox.
Materials and Methods: Analysis of the population sex ratio.
Results: Its trend- based on data generated by censuses from 1956 to 1996- indicate that a large proportion of women did not live beyond the age of 35 women were most likely to die in years 35-45 of their life. It is possible that this age group, which included many women who were still of reproductive age, suffered the effects of war and socioeconomic crises of the 1940's. The trend had improved by the time of the 1376 census and there is no singe of an increase in the sex ratio thereafter. This change is probably due to the improvement in socioeconomic status and the development of an effective health care system.
Conclusion: Since the life expectancy estimates are based on the probability of death and are thus affected by socioeconomic conditions, the apparent incompatibility between the population age pyramid and life expectancy among elderly women and men is due to higher mortality among women of reproductive age before the 1970’s.

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Background and Aim: Logistic regression is an analytic tool widely used in medical and epidemiologic research. In many studies, we face data sets in which some of the data are not recorded. A simple way to deal with such "missing data" is to simply ignore the subjects with missing observations, and perform the analysis on cases for which complete data are available.
Materials and Methods: We consider methods for analyzing logistic regression models with complete data recorded for some covariates (Z) but missing data for other covariates (X). When data on X are Missing At Random (MAR), we present a likelihood approach for the observed data that allows the analysis as if the data were complete.
Results: By this approach, estimation of parameters is done using both Maximum Likelihood and Bayesian methods through the Markov Chain Monte Carlo numerical computation scheme and the results are compared. The illustrative example considered in this article involves data from lung auscultations as part of a Health Survey in Tehran.
Conclusion: In comparing different methods, Bayesian estimates using the model described in this study are much closer to those generated by analysis of the full data by the standard model.

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Background and Aim: To describe the trends in research articles in the field of mental health.
Materials and Methods: The articles that we reviewed belonged to the fields of psychiatry, psychology, and neuroscience. We limited the search to the literature published over the 30-year period from 1973 to 2002. The following types of data were extracted: areas of research, specific topics, study design, location for data collection, funding sources, and the different types of working relationship among the authors.
Results: Analysis of publication trends in 3031 articles showed a marked increase in the total number of publications with time, especially over the last 5 years. As for different research areas, we detected a growing proportion of articles in the field of neuroscience and a decline in articles dealing with mental health. The volume of research in the fields of psychology, epidemiology and clinical sciences remained relatively constant. There was a rise in the proportion of cross-sectional studies and clinical trials in the second half of the 30-year period.
Conclusion: It is important to find the reasons and implications for the waning interest in mental health. Our results could provide an empirical basis in policy making and strategic planning for research in this area

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Background and Aim: In 1991, the world health organization initiated a project to simultaneously develop an instrument for measuring quality of life in 15 countries. The study yielded two questionnaires, namely WHOQOL-100 and WHOQOL-BREF. These were intended as generic QOL measurement tools to be used in a broad range of diseases, for different degrees of disease severity, and in various cultural subgroups. The objective of the current study was to evaluate the Iranian version of the WHOQOL-BREF. This 26-item instrument comprises four domains: Physical Health, Psychological, Social Relationship, Environment and the overall QOL/health.
Material and Methods: We administered the questionnaire to 1167 adults in Tehran. The stratified sample consisted of 476 diseased subjects and 700 healthy ones. We tested the instrument's reliability (internal consistency, test-retest), discriminant validity and factorial structure.
Results: The participants had an age mean of 36.3 years (SD = 13.2) and had an average 11.5 years of education. Using Cronbach's α and intraclass correlation, all domains met the minimum reliability standards, with the exception of social relationship domain (α = 0.55). The latter could be attributed the small number of questions in this domain and the sensitive nature of the questions themselves. Since 83% of the questions show maximum correlation with their original domain, the factorial structure of the questionnaire was regarded as acceptable. The questionnaire has the ability to discriminate different groups after adjustment for confounding factors in regression analysis.
Conclusion: This study demonstrated good to excellent reliability and acceptable validity in various groups of subjects in Iran. The instrument may be used in future studies, albeit with minor modifications in the domain of social relations, as determined by expert opinion.

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Background and Aim: Health surveillance systems are now paying more attention to infectious diseases, largely because of emerging and re-emerging infections. The main objective of this research is presenting a statistical method for modeling infectious disease incidence based on the Bayesian approach.

Material and Methods: Since infectious diseases have two phases, namely epidemic and non-epidemic, joint distributions seem preferable for modeling disease incidence. We used a hidden Markov model - suitable for joint distributions- to arrive at a statistical model applicable to infectious diseases. Parameter estimation was done using a Bayesian method. The resulting model was then applied to monthly incidence rates for malaria to test the model's applicability to real data.

Results: The error sum of squares of the model fitted to monthly incidence rates for malaria was 190.59 and the coefficient of determination between observed and fitted values was 0.84. It appears that the hidden Markov model with a cyclic regression equation has a proper goodness of fit when applied to malaria incidence rates.

Conclusion: The hidden Markov model is an efficient statistical tool for modeling infectious disease incidence rates.

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Background and Aim: The present article attempts to define the current trend for age at first marriage, based on the nationwide Health Survey of 1999 and using the Brass model.

Material and Methods: The national Health survey was conducted in 1999 and involved 1/1000 of the total population, selected via cluster sampling (clusters of 8 households each).

The sample used for the present study consisted of 16000 women aged 15-49, including 3026 women in Tehran province. Variables used for analysis were current age, marital status, age at first marriage and residential area (urban/rural). The mean age at first marriage for married women was 17.8 years (sd=3.7) for the whole country, and 18.2 years (sd=3.7) for Tehran province.

Results: The Brass model fitted to the data revealed a significant decreasing trend for the proportion of married women in all age groups, especially in the 15-19 year-old category.

Conclusion: This obviously indicates an upward trend for age at first marriage.

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Background and Aim: Breastfeeding is one of the most important health determinants in infancy and childhood: physical growth and mother-child bonding in this period are two factors that program cognitive ability in later life. The main aim of this study was to examine the long-term effects of breastfeeding on subsequent cognitive performance. 

Material and Methods: A cohort of 5362 births registered over a period of one week in March, 1946 was selected by stratified sampling, based on the subjects' social class. We collected data for ages 2, 8, 11, 15, 26, and 46 years, and these data were analyzed in 2004-2005 at the school of public health, Tehran. Linear structural equation models were fitted to the data by LISREL 8.12 software in order to find path models.

Results: Descriptive findings showed that children weighing ≥3500 grams at birth acquired the ability to walk, talk, stand, and sit earlier than others. Also, subgroups within the cohort showed different patterns of change in their cognitive scores. Analysis of variance revealed that after adjustment for sex, social class, age of talking, and age of walking breastfed children still had higher means of verbal and nonverbal scores at ages 8 and 15 compared to never-breastfed children. Path analysis indicated that breastfeeding and birth weight could program later-life cognitive performance directly or indirectly through the ages of 2, 8, 11, 15, 26, and 43 years. For instance, path coefficients from breastfeeding to ages of talking and walking, to 8-15 verbal scores, to 26-year cognitive scores, and then to memory and visual scores at age 43 were estimated -for females and males, respectively- and form left o the right as follows: -0.12 (se=0.02), -0.05 (se=0.02), 0.71 (se=.05), 0.10 (se=0.04) for women    -0.01 (se=0.02), -0.07 (se=0.01), 0.75 (se=0.06), 0.13 (se=0.06) for men.

Conclusion: There are significant relationships between some early life determinants and later cognitive performance we conclude that in longitudinal studies of later life abilities, early-life nutrition and birth weight should be incorporated in the path analysis of aging.