• Journal of Environmental Health Sciences
• /
• v.38 no.4
• /
• pp.277-290
• /
• 2012

Objectives: Diesel engine exhaust (DE) accounts for a significant percentage of air pollutants that are associated with various health outcomes including mortality, asthma, chronic bronchitis, respiratory tract infection, etc. In June, 2012, the International Agency for Research on Cancer (IARC) released the assessment results that classified DE as "carcinogenic to humans" (Group 1). This review is therefore focused on the lung cancer risks of DE. Methods: Literatures were searched using PubMed with key words of "diesel exhaust", "lung cancer", and other related terms for the period between 1990 and 2012. A total of 295 articles were searched and sixteen epidemiologic studies were identified as potentially relevant. Results: Sixteen epidemiologic studies about the lung cancer risks of workers exposed to DE in various occupations were summarized in two tables, 1) retrospective cohort studies and 2) case-control studies. Increased lung cancer risk, although not always smoking adjusted, was observed in 6 out of 8 retrospective cohort studies and 4 of 8 case-control studies. Conclusions: Diesel fuel is widely used in Korea. Exposure to DE is confirmed to be a human carcinogen by IARC. Noncancer health risks of DE also need careful attention as DE is a major source of fine-particle pollution. Along with the efforts for reducing the DE emission through improvements of diesel engines and fuel, and the use of alternative fuels, comprehensive health risk assessment of DE should be conducted to minimize the adverse health effects.

• Journal of Community Nutrition
• /
• v.1 no.1
• /
• pp.39-43
• /
• 1999

Anthropometric measurements, particularly weight and height, are the most commonly employed measures of nutritional status in epidemiologic studies because of their simplicity and ease of collection. However, the usefulness of the anthropometric indicator is controversial. The aim of this study was to evaluate the usefulness of the anthropometric indicator to represent the nutritional status of individual adult in epidemiologic studies. In order to evaluate the usefulness of the anthropometric indicator to represent the nutritional status of individual, the validity in terms of sensitivity and specificity of anthropometric indicators was estimated by comparing the biochemical indicators to the reference indicators. The relative validity of dietary intake indicators was also measured for comparison between the three indicators of biochemistry, anthropometry and dietary assessment. The results showed that sensitivity of weight and height and dietary indicators were 16.7 an 50.5, respectively comparing the reference value of 100 as biochemical indicator in identifying anemic adults. Whereas the sensitivity of weight and height and dietary indicators were 63.6 and 36.4, respectively comparing reference value of 100 in identifying hyperlipidemic individuals(obesity). In conclusion, the validity of weight and height is much lower than that of biochemical indicator, burt weight and height still has some usefulness in identifying anemic individuals. Especially, it is more useful in identifying hyperlipidemic individual adults thant in identifying anemic individuals.

• Journal of Environmental Health Sciences
• /
• v.38 no.3
• /
• pp.175-183
• /
• 2012

Objectives: Controversy regarding the relationship between exposure to Agent Orange and disease has progressed for more than four decades, both at home and abroad. Recently, the allegation by US veteran Steve House of the burial of Agent Orange at the US Army base Camp Carroll located in Waegwan-eup, Korea, has emerged. We reviewed published articles and reports related to Agent Orange. Methods: Articles and reports were collected online using the keywords 'agent orange' and 'health' and then reviewed. Results: A number of epidemiologic studies have reported disease outcomes due to exposure to Agent Orange, while others were unable to establish a link to the injuries of veterans of the Vietnam War. This can be explained by the fact that accurate exposure assessment should be carried out since exposure misclassification in epidemiologic studies can affect estimates of risk. In the case of the burial of Agent Orange at Camp Carroll, an exposure pathway could be through underground water supplies, which differs from the cases of Vietnam and Seveso in Italy. Conclusion: There still remains a dispute among academics regarding the relationship between exposure to Agent Orange and disease, although Agent Orange is a highly toxic chemical. This dispute indicates that accurate exposure pathway and exposure assessment is needed.

• Korean Journal of Community Nutrition
• /
• v.3 no.2
• /
• pp.273-280
• /
• 1998

This study was designed to estimate the improvement of Validity for food frequency questionnaire(FFQ) by offering multiple choice portion size in developing a questionnaire. Validity of the two methods(food frequency questionnaire I=FFQ I & Food frequency questionnaire II=FFQ II) was tested in comparison with reference method of the 7-day weighed record(7DWR). Dietary consumption data of the three methods(FFQ I, FFQ II & 7DWR) were collected from 101 female university students for the analysis. Validity was measured in two categories : One was the nutrient intake value from the three methods, the other was the identification of between individual variation within the group. Spearman's rank order correlation test and distribution graphs were used for the analysis. The result showed that individual intake value of the FFQII was closer to that of the 7DWR than that of the FFQ I.Spearman's rank order correlation between the FFQII and the 7DWR did not show any improved correlation. The distribution graphs of nutrient intake derived from both the FFQ I and the FFQII were different from that of the 7DWR. Therefore, it could be suggested that single one portion size food frequency questionnaire is an equally efficient method as a multiple choice food frequency questionnaire to be adopted in epidemiologic studies.

• The Korean Journal of Pain
• /
• v.34 no.3
• /
• pp.332-338
• /
• 2021

Background: Trigeminal neuralgia (TN) is one of the most painful disorder in the orofacial region, and many patients have suffered from this disease. For the effective management of TN, fundamental epidemiologic data related to the target population group are essential. Thus, this study was performed to clarify the epidemiological characteristics of TN in the Korean population. This is the first national study to investigate the prevalence of TN in Korean patients. Methods: From 2014 to 2018, population-based medical data for 51,276,314 subscribers to the National Health Insurance Service of Korea were used for this study. Results: The incidence of TN was 100.21 per 100,000 person-years in the year of 2018 in Korea, and the male to female ratio was 1:2.14. The age group of 51-59 years had the highest prevalence of TN. Constant increases in medical cost, regional imbalance, and differences in prescription patterns by the medical specialties were showed in the management of TN. Conclusions: The results in this study will not only help to study the characteristics of TN, but also serve as an important basis for the effective management of TN in Korea.

• Asian Journal of Atmospheric Environment
• /
• v.2 no.1
• /
• pp.68-74
• /
• 2008

We briefly show the results of indoor and personal $PM_{2.5}$ measurements in an epidemiologic study designed to evaluate the health risks of ambient $PM_{2.5}$ in Japan and the relationship between indoor and outdoor PM concentrations. The impact of indoor and outdoor PM pollution on health is described based on one morbidity study. The results of other studies on indoor $PM_{2.5}$ measurements are also described.

• Journal of Preventive Medicine and Public Health
• /
• v.37 no.4
• /
• pp.291-299
• /
• 2004

As there have been growing concerns about the adverse effects of air pollution on birth outcome, studies for this area has been carried out in different populations and sites. We reviewed the epidemiologic studies that evaluated the effects of air pollution on birth outcome such as low birth weight and preterm births. We identified the air pollution exposure during pregnancy was related with low birth weight and preterm birth, although there are differences among studies for the critical period of vulnerability. The biological mechanisms whereby air pollution might influence health of fetus are not clearly established. The exposure to carbon monoxide(CO) during pregnancy could increase fetal carboxyhemoglobin and result in tissue hypoxia. On the other hand, ambient particles less than $10{\mu}m$ in aerodynamic diameter($PM_{10}$) could lead to inflammation and increase blood viscosity. Controlling for potential confounders and valid assessment of exposure are the methodological issues remained in these epidemiologic studies. In the future, more studies are needed to investigate the effect of air pollution on preterm birth or stillbirths, considering the various exposure period and the biological mechanism.

• Journal of Environmental Health Sciences
• /
• v.48 no.3
• /
• pp.138-150
• /
• 2022

Background: Epidemiology is a fundamental study of public health, including environmental health, since the features and causes of diseases discovered through epidemiology provide crucial information for developing successful disease prevention strategies. Objectives: This paper tried to define the role and function of epidemiologic research in the field of environmental health, summarize examples of epidemiological studies with regard to selected environmental health events in South Korea, and address important issues that should be considered when conducting epidemiological research in the future. Methods: Epidemiological studies of selected environmental health events were reviewed and summarized in terms of their contribution to environmental health in South Korea. Based on the information, important issues were suggested for future epidemiological studies in environmental health. Results: The role and function of epidemiologic research in the field of environmental health includes the systematic description of the health effects caused by environmental exposure, verification of the causal relationship between environmental exposure and health effects, and provision of background data for conducting prevention strategies and developing policies. A number of epidemiological studies have contributed to characterizing and assessing the environmental risks involved in a series of environmental health events in South Korea. Conclusions: Important issues for future epidemiological studies may include health effects from chronic low-level environmental exposure, application of analytical epidemiology to elucidate causal relationships, use of exposure/disease/susceptibility biomarkers, accurate reconstruction of past exposure status, cohort recruitment and long-term follow-up, and in-advance surveillance of diseases with environmental causes.

• Journal of Preventive Medicine and Public Health
• /
• v.36 no.4
• /
• pp.303-313
• /
• 2003

General information is summarized, that is necessary to introduce a scientific assessment of the human health and exposure issue concerning dioxin and dioxin-like compound. Scientific literatures were reviewed to assess the background exposures to the dioxin-like compounds for normal residents. Epidemiologic studies were also reviewed to assess malignant and nonmalignant sweets of dioxins. In 1997, the International Agency for Research on Cancer classified 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a human carcinogen, primarily based on occupational cohort studies. The US Environmental Protection Agency made the same decision in it's Draft Dioxin Reassessment. Epidemiologic evidences point to a generalized excess of all cancers, without any pronounced excess at specific sites. Reported non-cancer effects included a range of conditions affecting most systems. Among them, chloracne, elevation in gamma glutamyl transferase(GGT), and alterations in reproductive hormones are related to TCDO, Other adverse outcomes, such as lipid concentrations, diabetes, circulatory and heart diseases, immunologic disorders, neurobehavioral effects, and developmental outcomes require further study before their respective relationships to TCDD can be more definitively assessed.

• The Journal of the Korean dental association
• /
• v.45 no.3 s.454
• /
• pp.169-181
• /
• 2007

In this second part of series report on evidence-based dentistry, the level of evidence and the methods for critical appraisal are discussed. The epidemiologic studies, namely clinical studies have some bias per se, and the degree of bias is somewhat predetermined by the study design. The level of evidence can be defined as the reliability of the clinical study and it is dependent on the degree of bias. Thus, it is important to determine the type of the study and to understand its structure before critically appraising them. Systematic reviews of primary studies, randomized controlled trials, nonrandomized clinical trials, cohort studies, case-control studies, and case reports / series constitute the clinical studies and the level of evidence follows the order of the studies listed above. Critical appraisal is the most important procedure in evidence-based dentistry. It is done to determine the credibility of research papers and their usefulness in the clinician s own practice. Critical appraisal is consisted of multiple questions that are helpful for evaluating validity and usefulness of the studies concerning therapy, diagnosis, prognosis, and causation.