Consistency between education reported in health survey and recorded in death certificate

Background: Education level is one indicator of socioeconomic position which, in several countries including South Korea, is provided though death certificate data. Its validity determines the usefulness of death certificate data for exploring the association between socioeconomic position and mortality. This study was to compare education recorded on the death certificate with that reported before death in a nationally representative cohort of participants in the National Health and Nutrition Examination Survey (NHANES). Methods: The 1998/2001 NHANES data contained unique 13-digit personal identification numbers that were individually linked to death certificate data from the Korean National Statistical Office. Duration of mortality follow-up was 7.1 years. The data from 513 deaths were used to determine sensitivity and specificity of education in death certificate and estimate agreement rates of education level between NHANES data and death certificate data. Odds ratios for agreement in education were also estimated. Covariates considered in the analyses were gender, age, duration between NHANES and death, and cause of death. Results: The proportion of deaths without recorded education in death certificate was very low (0.2%). A total of 29.4% discordant pairs were found. Sensitivity and specificity for college or higher education were 0.84 (95% confidence interval 0.71–0.97) and 0.99 (0.98–1.00). However, sensitivity was poor for middle school education. The overall agreement rate was 70.7% (66.8%–74.6%) when education was categorized into five groups and increased up to 88.9% (86.2%–91.6%) when three education categories were used. The magnitude of validity and reliability for education did not generally vary with age, duration between health survey and death, and cause of death. However, a significantly smaller likelihood of agreement was found for middle and elementary school education after adjusting for covariates. Conclusion: Low percentage of missing information on education in South Korean death certificate data could provide a great potential to monitor mortality inequalities. A more collapsed categorization in education would be recommended when a more definitive conclusion on educational mortality inequality is required.Young-Ho Khang, Hye Ryun Kim and John W Lync

Monitoring trends in socioeconomic health inequalities: it matters how you measure

Background: Odds ratio (OR), a relative measure for health inequality, has frequently been used in prior studies for presenting inequality trends in health and health behaviors. Since OR is not a good approximation of prevalence ratio (PR) when the outcome prevalence is quite high, an important problem may arise when OR trends are used in data in which the outcome variable (e.g., smoking or ill-health) is of relatively high prevalence and varies significantly over time. This study is to compare time trends of odds ratio (OR) and prevalence ratio (PR) for examining time trends in socioeconomic inequality in smoking. Methods: A total of 147,805 subjects (71,793 men and 76,017 women) aged 25–64 from three Social Statistics Surveys of Korea from 1999 to 2006 were analyzed. Socioeconomic position indicators were occupational class and education. Results: While there were no significant p values for trend in ORs of occupational class among men, trends for PRs were significant. In women, p values for OR trends were similar to those for PR trends. In males, RII by log-binomial regression showed a significant increasing tendency while RII by logistic regression was stable between years. In females, trends of RIIs by logistic regression and log-binomial regression produced a similar level of p values. Conclusion: Different methods of measuring trends in socioeconomic health inequalities may lead to different conclusions about whether relative inequalities are increasing or decreasing. Trends in ORs may overstate or understate trends in relative inequality in health when the outcome is of relatively high prevalence and that prevalence varies significantly with time.Young-Ho Khang, Sung-Cheol Yun and John W Lync

Six-month healing success rates after endodontic treatment using the novel GentleWave System: the pure prospective multi-center clinical study

Background: This prospective multi-center (PURE) clinical study evaluated healing rates for molars after root canal treatment employing the GentleWave® System (Sonendo, Inc., Laguna Hills, CA). Material and Methods: Eighty-nine patients met the inclusion criteria and consented for this clinical study after referral for a root canal treatment. All enrolled patients were treated with the GentleWave System. Five endodontists performed the clinical procedures and follow-up evaluations. Pre-operative, intra-operative, and post-operative data were collected from the consented patients. Each patient was evaluated for clinical signs and symptoms. Two trained, blinded, and independent evaluators scored the subject tooth radiographs for apical periodontitis using the periapical index (PAI). The teeth classified as healing or healed were considered as a success and composed of a cumulative success rate of healing. Statistical analysis was performed by using the Fisher’s exact test, Pearson correlation, and multivariate logistic regression analyses of the pre-operative prognostic factors at 0.05 significance level. Results: Seventy-seven patients were evaluated at six months with a follow-up rate of 86.5%. The cumulative success rate of healing was 97.4%. Eleven prognostic factors were identified using bivariate analyses. Using logistic analyses, the two prognostic significant variables that were directly correlated to healing were the pre-operative presence of periapical index (p value=0.016), and single treatment visits (p value=0.024). Conclusions: In this six-month PURE clinical study, the cumulative success rate of healing was 97.4% when patients were treated with the GentleWave® System

Ab initio studies of electronic structure of defects in PbTe

Understanding the detailed electronic structure of deep defect states in narrow band-gap semiconductors has been a challenging problem. Recently, self-consistent ab initio calculations within density functional theory (DFT) using supercell models have been successful in tackling this problem. In this paper, we carry out such calculations in PbTe, a well-known narrow band-gap semiconductor, for a large class of defects: cationic and anionic substitutional impurities of different valence, and cationic and anionic vacancies. For the cationic defects, we study a series of compounds RPb2n-1Te2n, where R is vacancy or monovalent, divalent, or trivalent atom; for the anionic defects, we study compounds MPb2nTe2n-1, where M is vacancy, S, Se or I. We find that the density of states (DOS) near the top of the valence band and the bottom of the conduction band get significantly modified for most of these defects. This suggests that the transport properties of PbTe in the presence of impurities can not be interpreted by simple carrier doping concepts, confirming such ideas developed from qualitative and semi-quantitative arguments

Monitoring trends in socioeconomic health inequalities: it matters how you measure

<p>Abstract</p> <p>Background</p> <p>Odds ratio (OR), a relative measure for health inequality, has frequently been used in prior studies for presenting inequality trends in health and health behaviors. Since OR is not a good approximation of prevalence ratio (PR) when the outcome prevalence is quite high, an important problem may arise when OR trends are used in data in which the outcome variable (e.g., smoking or ill-health) is of relatively high prevalence and varies significantly over time. This study is to compare time trends of odds ratio (OR) and prevalence ratio (PR) for examining time trends in socioeconomic inequality in smoking.</p> <p>Methods</p> <p>A total of 147,805 subjects (71,793 men and 76,017 women) aged 25–64 from three Social Statistics Surveys of Korea from 1999 to 2006 were analyzed. Socioeconomic position indicators were occupational class and education.</p> <p>Results</p> <p>While there were no significant p values for trend in ORs of occupational class among men, trends for PRs were significant. In women, p values for OR trends were similar to those for PR trends. In males, RII by log-binomial regression showed a significant increasing tendency while RII by logistic regression was stable between years. In females, trends of RIIs by logistic regression and log-binomial regression produced a similar level of p values.</p> <p>Conclusion</p> <p>Different methods of measuring trends in socioeconomic health inequalities may lead to different conclusions about whether relative inequalities are increasing or decreasing. Trends in ORs may overstate or understate trends in relative inequality in health when the outcome is of relatively high prevalence and that prevalence varies significantly with time.</p

South Korean Military Service Promotes Smoking: A Quasi-Experimental Design

∙ The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens

Micro-fabrication of Carbon Structures by Pattern Miniaturization in Resorcinol-Formaldehyde Gel

A simple and novel method to fabricate and miniaturize surface and sub-surface micro-structures and micro-patterns in glassy carbon is proposed and demonstrated. An aqueous resorcinol-formaldehyde (RF) sol is employed for micro-molding of the master-pattern to be replicated, followed by controlled drying and pyrolysis of the gel to reproduce an isotropically shrunk replica in carbon. The miniaturized version of the master-pattern thus replicated in carbon is about one order of magnitude smaller than original master by repeating three times the above cycle of molding and drying. The micro-fabrication method proposed will greatly enhance the toolbox for a facile fabrication of a variety of Carbon-MEMS and C-microfluidic devices.Comment: 16 pages, 5 figure

Development of vehicle door security using smart tag and fingerprint system

Research and development advancements in the area of Vehicle Door Security using Smart Tag and Fingerprint System. Fingerprint biometric is one of the popular, ubiquitous, reliable, economical and efficient biometric technologies. Due to its versatility, fingerprint biometric is applicable. Fingerprint is popular because of its universality, uniqueness, permanence, acceptability, performance [1]. The Arduino as a controller between RFID Sensor, Fingerprint Sensor, Buzzer, LCD, LED and Relay. This research implemented for security purpose to protect the safety of vehicle from vehicle theft or burglary. It is very useful and important for alert the people who have vehicle to protect it from theft. This is a very important system to be implemented at the main door of vehicle. The system started to work when the user access either than one system fingerprint or smart tag to lock and unlock the door. The fingerprint system only user can access their fingerprint whereas the smart tag system can access by user or user’s intimate relative when they borrow the vehicle for emergency. The vehicle door cannot be opened when unmatched fingerprint is access or incorrect smart tag is access. Once the incorrect smart tag is access by unauthorized person, the buzzer will be activated and produce a high level of alarm sound to alert the user. The Arduino Uno microcontroller is controlled by the entire system of the project. Hence, it is easy to implement and available to use because it has a simple function, so this system can be enhancing with modern technology so it can be applying into vehicle part for secure the vehicle

Socioeconomic disparities in behavioral risk factors and health outcomes by gender in the Republic of Korea

<p>Abstract</p> <p>Background</p> <p>Few studies have examined socioeconomic disparities in health and behavioral risk factors by gender in Asian countries and in South Korea, specifically. We investigated the relationship between socioeconomic position (education, income, and occupation) and subjective and acute and chronic health outcomes and behavioral risk factors by gender, and compared results from 1998 and 2005, in the Republic of Korea.</p> <p>Methods</p> <p>We examined data from a nationally representative stratified random sample of 4213 men and 4618 women from the 1998 Korea National Health and Nutrition Examination Survey, and 8289 men and 8827 women from the 2005 Korea National Health and Nutrition Examination Survey using General Linear Modeling and multiple logistic regression methods.</p> <p>Results</p> <p>Controlling for behavioral risk factors (smoking, drinking, obesity, exercise, and sleep), those in lower socioeconomic positions had poorer health outcomes in both self-reported acute and chronic disease and subjective measures; differences were especially pronounced among women. A socioeconomic gradient for education and income was found for both men and women for morbidity and self-reported health status, but the gradient was more pronounced in women. In 1998, the odds ratios (ORs) of higher morbidity for illiterate vs. college educated females was 5.4:1 and 1.9:1 for females in the lowest income quintile vs. the highest. The OR for education decreased in 2005 to 2.9:1 and that for income quintiles remained the same at 1.9:1. The OR of lower self-reported health status for illiterate vs. college educated females was 2.9:1 and 1.6:1 for females in the lowest income quintile vs. the highest in 1998, and 3.3:1 and 2.3:1 in 2005.</p> <p>Conclusions</p> <p>Among Korean adults, men and women in lower socioeconomic position, as denoted by education, income, and somewhat less by occupation, experience significantly higher levels of morbidity and lower self-reported health status, even after controlling for standard behavioral risk factors. Disparities were more pronounced for women than for men. Efforts to reduce health disparities in South Korea require attention to the root causes of socioeconomic inequality and gender differences in the impact of socioeconomic position on health.</p