Journal of School of Public Health and

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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.

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Background and Aim: We studied 1800 pregnant women receiving routine prenatal care in the urban and rural health centers of Shahr-e-Rey in south of Tehran, for a comparative assessment of 5-minute neonatal Apgar Scores in wanted versus unwanted pregnancies.

Material and Methods: The subjects were studied in 2 groups, each comprising 900 pregnant women. Group A consisted of mothers with wanted pregnancy and group B of mothers with unwanted pregnancy. Inclusion criteria were gestational age less than 28 weeks at the time of entering the study. The two groups were followed through their prenatal care to the time of delivery. For each neonate, we extracted the 5-minute Apgar score from the birth certificate.

For a more precise assessment, the impact of conditions affecting the Apgar score of newborns (such as normal vaginal delivery vs. caesarean section, premature birth, low birth weight, congenital anomalies, and birth place (hospital and health center, or house) was assessed by logistic regression.

Results: We found 15 cases (0.4%) of low 5-minute Apgar score (under 8) among newborns of wanted pregnancies and 4 such cases (1.1%) among those of unwanted pregnancies. The difference between the 2 groups was significant (P= 0.011). After applying the logistic regression model to adjust for other factors, unwanted pregnancies still had a significant association with low Apgar scores (increasing the risk 3-fold).The attributable risk for low 5-minute Apgar score in unwanted pregnancies was 0.54 (CI_.95 = 0.132 to 0.813).

Conclusion: The estimated attributable risk means that with 95% confidence, between 13.2% and 81.3% of the low Apgar scores could have been prevented by eliminating unwanted pregnancy. As there have been no similar studies in Iran, more research with larger samples must be performed to assess these results more precisely.

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Background and Aim: Presently not sufficient attention is paid to adolescent health promotion in many countries, because of the widespread belief that adolescents are generally healthy. The purpose of this study was to evaluate predictors of adolescent girls' quality of life using path analysis based on Pender's health promotion model.

Materials and Methods: The Pender's health promotion model served as the framework of this cross-sectional study, which included a total of 500 adolescent girls (grades 9-11) selected by stratified random sampling from 20 high schools for girls in 4 districts of Kashan province, Iran. Inclusion criteria were being in grades 9-11 and a written informed consent (from teachers, parents and the girls themselves). Data were collected through interviewing the girls, the interviewers being trained persons, using several standard questionnaires (for perceived self-efficacy, perceived affect, perceived barriers, perceived social support health promoting lifestyle, and health-related quality of life). Data analysis was done using SPSS18 and LISREL 8.8, the statistical test being path analysis.

Results: All constructs of the health promotion model and health promoting lifestyle were significantly related to adolescent girls' quality of life. Perceived self-efficacy (β=0.70, p<0/01) and perceived affect (β=0.21, p<0/01) had the highest correlation with the quality of life. The model and the health-promoting lifestyle as a mediator accounted for 73% and 39% of variance in adolescent girls' quality of life, respectively.

Conclusion: The findings of this study indicate that the health promotion model can be used to explain and predict the quality of life of adolescent girls. Thus, the Pender's health promotion model is recommended to health planners for promoting the quality of life in this population.

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  Background and Aim: High fruit and vegetable intake has been introduced as one of the key factors of healthy diet to prevent chronic disease. This study attempts to explore the fruit and vegetable intake in Arak city and its relationship with demography and socio-economic factors.

  Materials and Methods : In this cross sectional study, 660 people in 18 -70 age range were selected with a two-stage cluster sampling and were interviewed for demography and socio – economic questionnaires and a 56- items semi-quantitative food frequency questionnaire to assess fruit and vegetable intake. After univariate analysis, the association of the significant variables with fruit and vegetable intake was also evaluated with multiple linear regression.

  Results: In this study, over 60 percent of subjects consumed less than the minimum recommended amount of fruit and vegetable (5 servings or 400 gr a day).The total consumption of fruit and vegetable indicated an inverse significant relationship with age (p =0.04 and β = - 0.02), and a direct significant relationship with economic status (p <0.001and β =0.10). The father's educational level (p =0.005 and β =0.38 for diploma level and p =0.03 and β =0.36 for academic education) and physical activity level (p =0.001 and β =0.03 per hour) were factors associated with fruit consumption. The gender was only associated with vegetable consumption so that women had higher consumption in this study (p =0.03 and β=0.23).

  Conclusion: The findings of this study indicate low fruit and vegetable consumption in the population under study. In this study, age, physical activity, and socioeconomic status and fathers’ education were the factors that were significantly associated with fruit and vegetable consumption.

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  Background and Aim: In many diagnostic studies, including surveying the survival of patients with gastric cancer where each individual after surgery can experience more than one type of event, and the occurrence of one type of event hinders the occurrence of other types of events, the question of competing risk is raised. For checking the effect of each covariate on the occurrence of any event and estimating the hazard function, Cox and Fine and Gray models are used. In the event that the assumptions of two models do not hold, using them will be an incorrect course of action. One way to overcome this problem is to use models that have higher flexibility.

  Materials and Methods: In this study, the demographic, clinical and therapeutic characteristics of 330 patients with gastric cancer who referred from January 1996 to April 2000 to the Cancer Institute of Iran Imam Khomeini Hospital and underwent surgery, including their type, and the time of occurrence of the first event (locoreginal replace/death) for each patient from medical records were collected and evaluated. Using this information, the cumulative hazard function of relapse of disease was plotted by means of three models Cox, Fine and Gray and the flexible one, and was checked against the observed cumulative incidence function of recurrence of disease and, finally, their performance was evaluated.

  Results: Nearly, for each event, the proportionality assumption holds for all the variables . According to the graph of cumulative incidence function for the event of interest (recurrence), it can be seen that the Cox model, has overestimated the cumulative incidence function and the curves of two other models are very similar and also similar to the observed curve. However, the cumulative incidence function of the flexible model is smoother than the others.

  Conclusion: In the competing risk framework, Cox model is not very useful in practice while it seems that the flexible model is not only a good alternative to the Fine and Gray model but will also be superior to it when the assumption of proportionality does not hold.

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  Background and Aim: Work ability reflects the interactions among personal characteristics, working conditions, employees' functional capabilities, and also employees' health status. Hence, the aim of the present study was to provide the Farsi version of Work Ability Index and to validate it among Iranian workers.

  Materials and Methods: In the first stage, Backward Translation method was used for linguistic validation of the questionnaire. Cross sectional survey of a sample of 645 workers from some Iranian companies were conducted. The study estimated the reliability of the questionnaire by means of test-retest, as well as the construct validity using factor analysis. In order to determine discriminant capacity, the mean scores of different dimensions of work ability index were compared between workers with and without sick leave.

  Results: Accordingly, the questionnaire showed a good internal consistency. ICC coefficients for the questionnaire were acceptable. Moreover, factor analyses related to the questionnaire items indicated that only one question is sufficient for each item of "work ability in relation to the demands of the job" and "mental resources". Also, questions related to the item of "number of current diseases diagnosed by physician" can be integrated in six questions. A good level of discriminant validity was observed for all dimensions except for the item of "work ability regarding work demands".

  Conclusion: According to the acceptable validity and reliability of Work Ability Index, obtained in the present study, using this questionnaire for evaluating workers' work ability in all Iranian work environments, especially in industrial settings, is recommended.

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  Background and Aim: The aim of this study was to assess exposure of workers in a metal industry to nickel and lead.

  Materials and Methods: Extraction was done using the solid-phase extraction on Chromosorb-102 resin to prepare, concentrate and purify biological samples of urine, hair and nails of workers working in metal industries. The variables influencing response (pH, loading flow rate, elution solvent, and amount of resins, elution volume, and sample volume) were examined and the procedure was optimized. The optimized procedure was, then, validated based on the “within-day” and “day-to-day” reproducibility experiments, using low, medium and high concentrations, leading to a satisfactory accuracy and precision. Finally, lead and nickel samples were taken from the workers and their concentrations determined voltammetrically.

  Results: The optimum values for the examined parameters were as follows: pH = 9, ligand concentration = 0.05%, loading flow rate = 5 ml/min, elution solvent = 2M HNO₃, amount of resins = 500 mg, elution volume = 15 ml, and sample volume up to 500 ml. A good reproducibility and repeatability was obtained for the optimized method under the existing conditions. Lead and nickel could be extracted with recoveries in the range of 94-100%. On the whole, the concentrations of nickel and lead in the workers’ biological samples were above the respective maximum permitted levels.

  Conclusion: Solid-phase extraction procedure is a fast and simple method for preconcentrating and isolating analytes from biological samples. Considering the low concentrations of the analytes and presence of confounding factors in such samples, the procedure can be very effective for their preparation. The application of the developed method indicates that trace metal ions can be effectively purified and preconcentrated from different matrices like urine, hair and nail samples to assess occupational exposures.

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Background and Aim: A New Health Reform Plan consisting of seven programs was initiated in Iran in mid-May 2015 aiming to reduce the out-of-pocket payments, improve the public’s health, and promote the public health indicators. This study was conducted to determine the effect of the Plan on the performance indicators of Hamedan university hospitals.

Materials and Methods: In this longitudinal descriptive-analytical study, based on the interrupted time series design, data related to hospital performance indicators were collected from all (15) Hamedan University hospitals for a period of 15 months (7 months before, and 7 months after, the implementation of the Plan, with a one-month interval in between). The SPSS software was used for data analysis.

Results: The data indicated changes in all the performance indicators after the implementation of the Plan. The largest changes were in the number of emergency and selective surgeries and the smallest in the ratio of active to total beds. Further analysis of the data showed that, as compared to the same months in the previous year, only a small number of these changes (number of emergency surgical operations and the ratio of active to total beds) were statistically significant.

Conclusion: Based on the findings it can be concluded that changes have occurred in all the selected indicators as a result of implementation of the New Reform Plan, indicating that the Plan has affected favorably performance of the hospitals. However, the effects observed should be judged cautiously, considering the possible negative consequences such as induced demand and hospital workload increase in the long run.

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Background and Aim: Human resources in any organization are its main capital. They are the only unique asset that are not liable to depreciation over time, but they even create more added value. The Social Security Organization (SCO) as a social insurer organization needs urgent assessment of its human resource management. In this regard, it appears that such an essential assessment can be done using the European Foundation for Quality Management (EFQM) model.

Materials and Methods: This project was an applied descriptive study conducted at the Social Security General Department in Tehran, Iran. The data collection tool was a standard questionnaire for performance assessment based on the EFQM model, the reliability of which (0.989) was determined by using the Cronbach's alpha coefficient. A total of 388 questionnaires were distributed, of which 311 were completed and returned to the researcher; the response rate was 81%. Analysis of the data was done using the SPSS-16 software.

Results: The human resource managers in the SCO achieved a score of 495.72. The empowerment and results dimensions rated 261.34 and 198.38, respectively. In the empowerment dimension, policy and strategy criteria had the highest score (56.12) and process the lowest (51.28), while in the results dimension, community criteria had the highest (50.27) and the customers criteria the lowest (51.18) score.

Conclusion: Based on the findings it can be concluded that the European Foundation for Quality Management (EFQM) model is suitable for assessing both the performance, strengths and weaknesses of the Tehran Security General Department human resources and improving its performance. Certainly better implementation of programs and achieving excellence will be possible through sustainable collaboration.

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Safe food and proper nutrition play a vital role in the health of populations. Food-borne diseases are a serious public health problem. Food handlers working in the kitchen play an important role in the transmission of foodborne diseases. Food-borne diseases, especially those caused by bacteria, viruses, parasites and fungi, are preventable. Proper manpower training is a key factor in provision of safe food and prevention of malnutrition.
Materials and Methods: A descriptive, cross-sectional and applied study was conducted in 10 hospitals affiliated with Tehran University of Medical Sciences in 2017. The knowledge, attitude and practice of 136 food handlers working in the kitchens of the hospitals was assessed using questionnaires.
Results: Analysis of the data showed that 8.08% of the participants had a good knowledge about food hygiene and safety (a score above 75%), while 16.7% of them achieved the full score as regards attitude. The hospitals’ performance was at a desirable level. The level of food hygiene and safety knowledge of the food handlers was significantly associated with their refresher trainings (p <0.05).
Conclusion: It can be concluded that the awareness of food handlers in most of the hospitals about food hygiene and safety is not sufficiently high. It is suggested to design and implement proper refresher training crash courses, as well as sensitize the personnel.

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Background and Aim: Cardiovascular diseases (CVD) are the leading cause of death globally, causing annually 17.3 million deaths, more than 75% of these deaths occurring in the low- and middle-income countries. Although extensive studies have been conducted to determine the risk factors for these diseases, limited studies have been performed to investigate these factors using a multilevel analysis method. The aim of this study was to determine the CVD risk factors in the staff of Mashhad University of Medical Sciences using a multilevel analysis approach, as well as compare the application of the conventional and multilevel logistic regressions in doing this according to the hierarchical structure of the data.
Materials and Methods: This was a case-control study including a total of 1091 randomly selected individuals from among the people in a prospective cohort study, namely, the “PERSIAN Cohort Study in Mashhad University of Medical Sciences” in 2018.  The case group included 152 patients with a definite diagnosis of CVD and the control group 939 staff members not suffering at the time from CVD. Data analysis was done using the STATA software. Data analysis (based on frequencies and percentages) was done using one-way and two-level logistic regression analysis at α = 0.05.
Results: Multivariate analysis showed that hypertension, smoking, fasting blood sugar and cholesterol were among the cardiovascular risk factors with a significant relationship with the disease. Based on the two-tier logistic regression model, the odds ratio for CVD in the hypertensive patients was 3.93 times that in individuals with a normal blood pressure with a confidence interval of 2.64-6.28. The risk in smokers was 1.85 (1.11-3.09) times that in nonsmokers. The CVD odds ratio in individuals with a high fasting blood glucose level (undiagnosed/uncontrolled diabetes) was 2.7 (1.18-6.18) times that in those with a normal blood pressure. There were no statistically differences between the case and control groups as regards the other variables ─ body mass index, diabetes (controlled or uncontrolled), or blood triglyceride level.
Conclusion: The findings show that statistical model selection can influence the results of data analysis in a dataset. It should be noted that the results of this study indicate a high prevalence of some cardiovascular risk factors among the staff. Another crucial point in this study is that the level of physical activity of the staff was found to be low, which would result in increased risk of overweight and obesity.
 

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Background and Aim: Food preferences and health literacy ─ key determinants of food choices in childhood and adolescence ─ are determinants of chronic diseases in adulthood. This study aimed to determine associations between food preferences, health literacy and body mass index (BMI) among elementary school students in Malekan city, east Azarbayejan Province, Iran in 2021-2022.
Materials and Methods: This cross-sectional descriptive-analytical study included 582 male and female primary-schoolers in the fourth, fifth and sixth grades in both the public and private  schools in Malekan County (Malekan, Lilan, and Mubarakshahr) selected by the two-stage randomized cluster method. A questionnaire including background questions and questions about health literacy and a researcher-made checklist of food preferences was used to collect data online using the Pros-Online Platform. The content validity ratio and index were used to determine validity and Cronbach's alpha index to check for the reliability of the questionnaire (CVI=0.98, CVR=0.91, Cronbach's alpha > 0.7). Data were analyzed using Mann-Whitney, t-test, one-way analysis of variance, Kruskal-Wallis and Chi-square tests at a significance level of 0.05 using SPSS 26.
Results: The average health literacy score of all the students was rather low (52.9±00.33), that of the female students (55.7±36.49) being slightly higher than that of the boys (49. 9±29.79). Further analysis of the data showed that there was a statistically significant relationship between the students' food preferences and health literacy variables (p<0.001). Furthermore, statistically significant relationships were observed between the students' BMI and their food preferences (p˂0.001) and health literacy (p˂0.001).
Conclusion: Considering the low level of health literacy of the adolescents and a positive relationship between health literacy, food preferences and BMI in adolescents, it can be concluded that increasing their health literacy will improve their healthy food choices. Therefore, it seems that interventions based on a theoretical framework aiming at increasing the students’ health literacy and improving their food preferences can be beneficial to them as a potential strategy for improving their healthy eating patterns resulting in preventing overweight and obesity.                
 

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Background and Aim: Considering the quality of prenatal care services, indentification of the avoidable and inevitable maternal factors and proper promotion of the knowledge and skills of health care service providers is vital for providing suitable preventive and interventional services with the aim of ensuring a successful pregnancy and proper management in the health care system.  This study was conducted to compare the adverse pregnancy outcomes among women with or without a history of Covid-19 in the pregnancy and postpartum stages covered by the Babol University of Medical Sciences, Babol, Iran.
Materials and Methods: This was a descriptive-analytical cross-sectional study including 4124 women, either pregnant or after a recent childbirth (with or without Covid-19) between 20.2.2020  and  29.3.2022, registered in the Sib electronic system (hereinafter Sib) of Babol University of Medical Sciences, Babol, Iran. Using a checklist developed and validated by an expert panel data were collected on the prevalence of maternal and neonatal outcomes in mothers with or without a history of Covid-19 and compared. The data collected were analyzed with SPSS 24 using descriptive tests such as chi-square and Fisher's exact test and STATA version 22, and the adverse outcomes with high frequencies following Covid-19 were determined.
Results: Analysis of the data showed the following to be the most common outcomes among mothers with a history of Covid-19: 1. obstetric complications and maternal disorders/diseases (hypertension, type-2 diabetes mellitus, at least one case of bleeding during pregnancy, premature/delayed birth and premature rupture of the amniotic sac, n= 457, 27.8%); 2. medical and surgical problems (unhealthy pregnancy weight gain and thromboembolic events, n=206, 12.5%). In addition, there was a statistically significant difference between the two groups of pregnant mothers with and without a Covid-19 infection as regards medical and surgical problems (P=0.001) and obstetric complications and maternal diseases (p=0.002). As regards the adverse neonatal outcomes in pregnant mothers with and without a history of Covid-19, there was a statistically significant difference between the two groups in terms of Apgar score at minutes 1 and 5 (p≥0.001) and exclusive breastfeeding (P=0.001) and the presence of Covid-19 symptoms in the baby (p<0.001).
Conclusion: Based on the findings of this study it seems that Covid-19 infection during pregnancy is associated with a higher risk of some of the undesirable maternal and neonatal outcomes.  Therefore, it is essential to plan and implement programs for health education, creation of a sound attitude towards better management, enhancement of the skills and capabilities of the health-care providers and, finally, promotion of the knowledge of service recipients. 
 

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Background and Aim: Despite all the current diabetes prevention programs, only a limited number of patients are identified and receive care.
Materials and Methods: This was a cross-sectional descriptive-analytical study including individuals over 30 years old in Buin Zahra city, Iran selected using the multi-stage sampling method (sample size = 1154). Data were collected using a questionnaire for the general public and the health team, the validity and reliability of which had been determined based on the CVR and CVI indexes and the correlation coefficient, respectively.
Results: The average age of the sample and the prevalence of diabetes were 48.42 ± 14.45 years and 9.9%, respectively. Further analysis of the data showed the following:
1. the prevalence of diabetes in at-risk people: women with a history of abortion and large children, 12.8% and 31.7%, respectively; gestational diabetes 36.5%;
2. obesity during pregnancy: 19.7%; a family history of diabetes: 22.4%;
3. waist circumference>90 cm: 14.08%, BMI>25: 13.95%; and
4. triglyceride<200: 22%, hypertension: 32.97%.
Further analysis of the data showed statistically significant associations between diabetes and blood sugar level above 100 mg/dl (OR = 2.73), waist circumference >90 cm (OR = 3.02) and gestational diabetes (OR =12.22); no other significant associations were found.
Only 55% of the health team personnel had received diabetes prevention training.
Conclusion: It can be concluded that patient care and education are not of a proper quality. The considerable prevalence of diabetes among people at risk shows that more follow-up and care are needed for them. The training of health team personnel should be very efficient and the number of trainings related to the diabetes program should increase.