Objective: To investigate the population size of transgender women (TGW) in Tianjin and analyze the characteristics of their sexual behaviors to provide a basis for AIDS prevention and control. Methods: To estimate the population size of TGW in Tianjin using the capture-recapture method. At the same time, an anonymous questionnaire was collected to conduct a multi-factor logistic analysis of the TGW population's sexual behavior. Results: A total of 213 TGW were investigated. Tianjin's estimated TGW population size was 599 (95%CI: 407-792). Multivariate logistic analysis of the use of condoms consistently showed that compared with TGW without regular sex partners, those with regular sex partners had a lower proportion of consistent condom use (aOR=0.44, 95%CI: 0.23-0.82) and had received HIV tests in the last year were more likely to adhere to condom use than those who had not been tested (aOR=2.73, 95%CI: 1.06-6.99). Conclusion: It is necessary to strengthen HIV mobilization testing among the TGW population and their regular sexual partners to improve condom use.
Humans ; Female ; Population Density ; Transgender Persons ; Sexual Behavior ; Sexual Partners ; HIV Infections/prevention & control*

Capture-recapture method is an economical and straightforward method widely used in fields such as estimating population size and estimating and adjusting incidence or prevalence. This paper reviews the classical capture-recapture method and its improvement and application in population size estimation in referring the subsequent related work.
Humans ; Incidence ; Population Density ; Prevalence ; Research Design

Respondent-driven sampling (RDS) is a method of sampling specifically for hidden populations, often applied to transgender women, female sex workers, men who have sex with men, and other groups that are difficult to identify and contact because of stigma and legal constraints. However, this method is gradually applied to the general population. With the continuous improvement of RDS, studies find that the network size of RDS samples can be weighted to estimate the overall situation and population size. This article summarizes the current application progress of RDS in population size estimation and provides ideas for the development of RDS and the use of RDS to carry out relevant research.
Female ; HIV Infections/epidemiology* ; Homosexuality, Male ; Humans ; Male ; Population Density ; Sampling Studies ; Sex Workers ; Sexual and Gender Minorities ; Surveys and Questionnaires

Network scale-up method is an indirect population size estimation method based on social network theory. It is widely used in estimating the hidden population size because it does not need to contact the target population. In order to provide reference for the further application of this method, this paper summarizes the traditional network scale-up method, the progress of this method and its combination with new survey techniques.
Humans ; Population Density ; Surveys and Questionnaires

BACKGROUND: Regional disparities in the working conditions of medical doctors have not been fully assessed in Japan. We aimed to clarify these differences in hospital characteristics: doctors' workload, wages, and popularity among medical students by city population sizes. METHODS: We targeted 423 teaching hospitals certified by the Japanese Society of Internal Medicine and assessed the working conditions of physicians specializing in internal medicine. We calculated their workload (the annual number of discharged patients per physician) and retrieved data on junior residents' monthly wages from the Resinavi Book which is popular among medical students in Japan to know the teaching hospital's information and each hospital's website. Furthermore, we explored the interim matching rate of each hospital as its popularity among medical students. Next, we classified cities in which all hospitals were located into eight groups based on their population size and compared the characteristics of these hospitals using a one-way analysis of variance. RESULTS: The average workload was 110.3, while the average workload in hospitals located in most populated cities (≥ 2,000,000) was 88.4 (p < 0.05). The average monthly wage was 351,199 Japanese yen, while that in most populated cities was 305,635.1 Japanese yen. The average popularity (matching rate) was 101.9%, and the rate in most populated areas was 142.7%, which was significantly higher than in other areas. CONCLUSIONS Hospitals in most populated areas had significantly lower workloads and wages; however, they were more popular among medical students than those in other areas. This study was the first to quantify the regional disparities in physicians' working conditions in Japan, and such disparities need to be corrected.
Cities/statistics & numerical data* ; Geography ; Hospitals, Teaching/statistics & numerical data* ; Japan ; Physicians/statistics & numerical data* ; Population Density ; Salaries and Fringe Benefits/statistics & numerical data* ; Students, Medical/psychology* ; Workload/statistics & numerical data*

population.SUBJECTS/METHODS: This retrospective, cross-sectional study included 8,732 men and postmenopausal women over 50 years old who completed the Korean National Health and Nutrition Survey (KNHANES) between 2008 and 2011. Potassium consumption was evaluated using a 24-hour recall method. Bone mineral density (BMD) was measured at three sites (total hip, femur neck, and lumbar spine) by dual-energy X-ray absorptiometry (DEXA). Multinomial logistic regression was used to examine the link between potassium intake and prevalence of osteoporosis and osteopenia, after controlling for potential confounding variables.RESULTS: The BMD of the total femur and Ward's triangle were significantly different according to the potassium intake among men (P = 0.031 and P = 0.010, respectively). Women in the top tertile for potassium intake showed higher BMD than those in the bottom tertile at all measurement sites (all P < 0.05). Daily potassium intake was significantly related to a decreased risk of osteoporosis at the lumbar spine in postmenopausal women (odds ratios: 0.68, 95% confidence interval: 0.48-0.96, P trend = 0.031). However, the dietary potassium level was not related to the risk of osteoporosis in men.CONCLUSION: Current findings indicate that higher dietary potassium levels have a favorable effect on bone health and preventing osteoporosis in older Korean women.]]>
Absorptiometry, Photon ; Adult ; Bone Density ; Bone Diseases, Metabolic ; Calcium ; Confounding Factors (Epidemiology) ; Cross-Sectional Studies ; Epidemiology ; Female ; Femur ; Femur Neck ; Hip ; Humans ; Logistic Models ; Male ; Methods ; Nutrition Surveys ; Osteoporosis ; Population Surveillance ; Potassium ; Potassium, Dietary ; Prevalence ; Retrospective Studies ; Spine ; Vitamin D

PURPOSE: There are known differences in embryology, clinical symptoms, incidences, molecular pathways involved, and oncologic outcomes of right-sided and left-sided colorectal cancers. However, immunologic study has only been characterized for healthy adults. The present study was designed to identify differences in immune cell populations in patients with right-sided and left-sided colorectal cancers.METHODS: A total of 35 patients who underwent colorectal resection for cancer between November 2016 and August 2017 at a tertiary teaching hospital were enrolled in this study. Patients were excluded if they had a disease affecting their immune system. Populations of immune cells, including mucosal-associated invariant T (MAIT), gamma delta T, invariant natural killer T, T, natural killer, and B cells, were measured in the peripheral blood and cancer tissues using flow cytometry, and then assessed based on the origin of the colorectal cancer.RESULTS: Fifteen had right-side and 20 had left-side colorectal cancer. There were no significant differences between the 2 cohorts for patient characteristics including pathologic stage. Peripheral blood from patients with right-side colon cancers contained fewer MAIT (0.87% right-side vs. 1.74% left-side, P = 0.028) and gamma delta T cells (1.10% right-side vs. 3.05% left-side, P = 0.002). Although the group with right-side colorectal cancer had more MAIT cells in cancer tissues (1.71% vs. 1.00%), this difference was not statistically significant.CONCLUSION: There is a difference in population sizes of immune cells in blood between patients with right-sided and leftsided colon cancers. The immune cell composition was determined to be distinct based on embryologic origin.
Adult ; B-Lymphocytes ; Cohort Studies ; Colonic Neoplasms ; Colorectal Neoplasms ; Embryology ; Flow Cytometry ; Hospitals, Teaching ; Humans ; Immune System ; Incidence ; Population Density ; T-Lymphocytes

OBJECTIVES: To summarize the evidence regarding the association of parity and breast feeding duration with the risk of osteoporosis in postmenopausal Korean women. This was because studies have been inconsistent regarding the effect of parity and breast feeding duration on the risk of osteoporosis. METHODS: A systematic literature search of relevant studies published by December 26, 2018 was conducted in PubMed, EMBASE, the Cochrane Library, CINAHL, RISS, KISS, KMbase, and KoreaMed. Outcome estimates of odds ratio (OR) or standardized mean difference were pooled with fixed or random-effect model. In case of heterogeneity, subgroup analysis was conducted. RESULTS: Seven cross-sectional studies (with 3,813 subjects) were included in the analysis. OR for osteoporosis was 1.43 (95% confidence interval [CI] = 1.09–1.88, P = 0.010) in postmenopausal women with higher parity compared to those with less parity. Moreover, OR for osteoporosis was 1.93 (95% CI = 1.28–2.93, P = 0.002) in postmenopausal women with longer durations of breast feeding than in those with shorter durations of breast feeding. CONCLUSIONS: This study revealed that duration of breast feeding increased the risk of osteoporosis in postmenopausal Korean women. More cohort studies with high quality research designs are needed to confirm our results.
Bone Density ; Breast Feeding ; Breast ; Cohort Studies ; Cross-Sectional Studies ; Female ; Humans ; Odds Ratio ; Osteoporosis ; Parity ; Population Characteristics ; Postmenopause ; Research Design

OBJECTIVES: Estimating influenza-associated mortality is important since seasonal influenza affects persons of all ages, causing severe illness or death. This study aimed to estimate influenza-associated mortality, considering both periodic changes and age-specific mortality by influenza subtypes. METHODS: Using the Microdata Integrated Service from Statistics Korea, we collected weekly mortality data including cause of death. Laboratory surveillance data of respiratory viruses from 2009 to 2016 were obtained from the Korea Centers for Disease Control and Prevention. After adjusting for the annual age-specific population size, we used a negative binomial regression model by age group and influenza subtype. RESULTS: Overall, 1 859 890 deaths were observed and the average rate of influenza virus positivity was 14.7% (standard deviation [SD], 5.8), with the following subtype distribution: A(H1N1), 5.0% (SD, 5.8); A(H3N2), 4.4% (SD, 3.4); and B, 5.3% (SD, 3.7). As a result, among individuals under 65 years old, 6774 (0.51%) all-cause deaths, 2521 (3.05%) respiratory or circulatory deaths, and 1048 (18.23%) influenza or pneumonia deaths were estimated. Among those 65 years of age or older, 30 414 (2.27%) all-cause deaths, 16 411 (3.42%) respiratory or circulatory deaths, and 4906 (6.87%) influenza or pneumonia deaths were estimated. Influenza A(H3N2) virus was the major contributor to influenza-associated all-cause and respiratory or circulatory deaths in both age groups. However, influenza A(H1N1) virus–associated influenza or pneumonia deaths were more common in those under 65 years old. CONCLUSIONS: Influenza-associated mortality was substantial during this period, especially in the elderly. By subtype, influenza A(H3N2) virus made the largest contribution to influenza-associated mortality.
Aged ; Cause of Death ; Centers for Disease Control and Prevention (U.S.) ; Cost of Illness ; Humans ; Influenza, Human ; Korea ; Mortality ; Orthomyxoviridae ; Pneumonia ; Population Density ; Seasons

BACKGROUND: We aimed to evaluate the spatial and temporal trends of the health burden attributable to particulate matter less than 2.5 µm in diameter (PM2.5) in the metropolitan cities and provinces of the Korea. METHODS: We used modeled PM2.5 concentration data for the basic administrative levels, comprising the cities and the provinces of Korea, the corresponding annual population census data for each level, and the age and cause specific mortality data. We applied cause-specific integrated exposure-response functions to calculate the premature mortality attributable to ambient PM2.5 for four disease end points (ischemic heart disease [IHD], chronic obstructive pulmonary disease [COPD], lung cancer [LC], and cerebrovascular disease [stroke]) for the year 2015. Moreover, the temporal trends of the health burden from 2006 to 2015 were assessed. RESULTS: The annual average PM2.5 concentration for Korea was 24.4 μg/m3, and 11,924 premature deaths were attributable to PM2.5 exposure in 2015. By simulating the reduction in the annual mean values of PM2.5 to 10 µg/m3, about 8,539 premature deaths were preventable. There was spatial variation in mortality burden attributable to PM2.5 across the sub-national regions of Korea. In particular, the high burden was concentrated at Seoul and Gyeonggi province due to the high population density. However, decreasing trends were noted for most of the metropolitan cities and provinces of Korea since 2006. CONCLUSION: Our findings show that further actions to improve air quality in Korea would substantially improve the health burden due to particulate matter.
Censuses ; Cerebrovascular Disorders ; Gyeonggi-do ; Heart Diseases ; Korea* ; Lung Neoplasms ; Mortality ; Mortality, Premature ; Particulate Matter ; Population Density ; Pulmonary Disease, Chronic Obstructive ; Seoul