• Safety and Health at Work
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• 제8권1호
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• pp.36-41
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• 2017

Background: Police work is generally sedentary although there may be situations that require physical endurance and strength, such as foot chases and arresting suspects. Factors such as excessive body fat can impede an officer's physical ability to deal with such occurrences. Our objective was to examine associations between officers' body fat percentage (BF%) and performance on a standardized fitness protocol. Methods: Data were obtained from fitness screening among 1,826 male and 115 female officers in a large US police agency. The screening consisted of a 2.4-km run, push-ups, sit-ups, and sit-and-reach test. Sex-specific body fat percentages were estimated from skinfold thickness measured using calipers. Linear regression models were used to examine unadjusted and adjusted mean scores of fitness tests across BF% tertiles. Results: The prevalence of overall fitness was 4.3 times greater in male officers and 3.6 times greater in female officers having the lowest BF% tertile compared with the highest tertile (30.3% vs 7.1% and 46.0% vs 12.8%, respectively). BF% was linearly and positively associated with the time of 2.4-km run (p < 0.001), and linearly and inversely associated with the number of push-ups (p < 0.001), sit-ups (p < 0.001), and the distance of sit-and-reach (p < 0.001) in men. Similar associations were observed in women with the exception of sit-and-reach (p = 0.122). Associations were independent of age, race/ethnicity, rank, and duty station. Conclusion: Overall, BF% was inversely associated with fitness levels in male and female officers. Future longitudinal studies should be initiated to explore the potentially causal relationship between BF% and fitness in law enforcement officers.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4467-4474
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• 2014

Background: We aimed to comprehensively review the evidence for using sputum DNA to detect non-small cell lung cancer (NSCLC). Materials and Methods: We searched PubMed, Science Direct, Web of Science, Chinese Biological Medicine (CBM), Chinese National Knowledge Infrastructure (CNKI), Wanfang, Vip Databases and Google Scholar from 2003 to 2013. The meta-analysis was carried out using a random-effect model with sensitivity, specificity, diagnostic odd ratios (DOR), summary receiver operating characteristic curves (ROC curves), area under the curve (AUC), and 95% confidence intervals (CI) as effect measurements. Results: There were twenty-two studies meeting the inclusion criteria for the meta-analysis. Combined sensitivity and specificity were 0.62 (95%CI: 0.59-0.65) and 0.73 (95%CI: 0.70-0.75), respectively. The DOR was 10.3 (95%CI: 5.88-18.1) and the AUC was 0.78. Conclusions: The overall accuracy of the test was currently not strong enough for the detection of NSCLC for clinical application. Dscovery and evaluation of additional biomarkers with improved sensitivity and specificity from studies rated high quality deserve further attention.

• Communications for Statistical Applications and Methods
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• 제23권5호
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• pp.385-397
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• 2016

The stress-strength models have been intensively investigated in the literature in regards of estimating the reliability ${\theta}$ = P(X > Y) using parametric and nonparametric approaches under different sampling schemes when X and Y are independent random variables. In this paper, we consider the problem of estimating ${\theta}$ when (X, Y) are dependent random variables with a bivariate underlying distribution. The empirical and kernel estimates of ${\theta}$ = P(X > Y), based on bivariate ranked set sampling (BVRSS) are considered, when (X, Y) are paired dependent continuous random variables. The estimators obtained are compared to their counterpart, bivariate simple random sampling (BVSRS), via the bias and mean square error (MSE). We demonstrate that the suggested estimators based on BVRSS are more efficient than those based on BVSRS. A simulation study is conducted to gain insight into the performance of the proposed estimators. A real data example is provided to illustrate the process.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3121-3123
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• 2015

The main objective of this paper was to assess the influence of educational level on the survival of uterine cervix cancer patients in our population. A total of 224 patients were registered in our registry, of which 178 had information on stage and different educational levels. The overall median survival (MS) was 23 months, with values of 18.5, 20.7 and 41.3 months for the illiterate, literate and qualified groups, respectively. In the illiterate patients, stage I was seen in 2.6% and stage IV in 11.8%, while in other 2 groups stage I was seen in 10% to 17% of patients at the time of diagnosis. The survival probability at around 50 months was around 42%, 30% and 26% (approximately) for qualified, literates and illiterates respectively [Log Rank (Mantel-Cox) showed p=0.023]. Emphasis on imparting education to females can be a part of comprehensive cancer control programme for improving the overall survival in patients with carcinoma of the uterine cervix in our population.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.775-780
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• 2013

Background: In the year 2010, it is estimated that nearly 0.36 million new cases and 0.19 million deaths with Non-Hodgkin lymphoma occurred. In India, among males, NHL incidence rates vary across the country which has encouraged us to conduct a case-control study to study risk factors. Materials and Methods: The present unmatched hospital-based case-control study conducted at Tata Memorial Hospital included subjects registered between the years 1997-99. There were 390 'lymphoma cases' and 1,383 'normal controls. Results: Data on age, tobacco habits, occupational history, dietary factors, tea, coffee were collected by the social investigators. Univariate and multivariate methods were applied for obtaining the odds ratios for risk factors. Conclusions: In the study, cigarette smoking (OR=2.0) and bidi smoking (OR=2.8), were associated with excess risk of lymphoma. Among the dietary items, only consumption of mutton showed 7.3-fold significant excess risk for lymphoma. Consumption of milk showed a 6-fold excess risk (OR=1.5); while coffee showed a 50% reduction in risk for lymphoma. Among occupational exposure, exposure to use of pesticides showed 3-fold excess risk for lymphoma.

• 응용통계연구
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• 제25권5호
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• pp.719-731
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• 2012

Agreement analysis is conducted to assess reliability among rating results performed repeatedly on the same subjects by one or more raters. The kappa statistic is commonly used when rating scales are categorical. The simple and weighted kappa statistics are used to measure the degree of agreement between two raters, and the generalized kappa statistics to measure the degree of agreement among more than two raters. In this paper, we compare the performance of four different generalized kappa statistics proposed by Fleiss (1971), Conger (1980), Randolph (2005), and Gwet (2008a). We also examine how sensitive each of four generalized kappa statistics can be to the marginal probability distribution as to whether marginal balancedness and/or homogeneity hold or not. The performance of the four methods is compared in terms of the relative bias and coverage rate through simulation studies in various scenarios with different numbers of raters, subjects, and categories. A real data example is also presented to illustrate the four methods.

• Communications for Statistical Applications and Methods
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• 제24권3호
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• pp.241-254
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• 2017

Drawing a sample can be costly or time consuming in some studies. However, it may be possible to rank the sampling units according to some baseline auxiliary covariates, which are easily obtainable, and/or cost efficient. Ranked set sampling (RSS) is a method to achieve this goal. In this paper, we propose a modified approach of the RSS method to allocate units into an experimental study that compares L groups. Computer simulation estimates the empirical nominal values and the empirical power values for the test procedure of comparing L different groups using modified RSS based on the regression approach in analysis of covariance (ANCOVA) models. A comparison to simple random sampling (SRS) is made to demonstrate efficiency. The results indicate that the required sample sizes for a given precision are smaller under RSS than under SRS. The modified RSS protocol was applied to an experimental study. The experimental study was designed to obtain a better understanding of the pathways by which positive experiences (i.e., goal completion) contribute to higher levels of happiness, well-being, and life satisfaction. The use of the RSS method resulted in a cost reduction associated with smaller sample size without losing the precision of the analysis.

• Journal of Preventive Medicine and Public Health
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• 제31권4호
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• pp.875-884
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• 1998

Missing observations are common in medical research and health survey research. Several statistical methods to handle the missing data problem have been proposed. The EM algorithm (Expectation-Maximization algorithm) is one of the ways of efficiently handling the missing data problem based on sufficient statistics. In this paper, we developed statistical models and methods for survey data with multivariate missing observations. Especially, we adopted the EM algorithm to handle the multivariate missing observations. We assume that the multivariate observations follow a multivariate normal distribution, where the mean vector and the covariance matrix are primarily of interest. We applied the proposed statistical method to analyze data from a health survey. The data set we used came from a physician survey on Resource-Based Relative Value Scale(RBRVS). In addition to the EM algorithm, we applied the complete case analysis, which uses only completely observed cases, and the available case analysis, which utilizes all available information. The residual and normal probability plots were evaluated to access the assumption of normality. We found that the residual sum of squares from the EM algorithm was smaller than those of the complete-case and the available-case analyses.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.867-872
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• 2016

Background: Esophageal cancer is one of the most serious malignancies. Due to the aggressive nature of this cancer, the prognosis is poor. A network meta-analysis with simultaneous comparison of multiple treatments can help determine better treatment options that have higher effects on overall survival of patients with lower adverse events. The aim of this review is to simultaneously compare efficacy and adverse events of treatment interventions for esophageal cancer. Materials and Methods: In this review, only randomized control trials (RCT) will be considered for network meta-analysis. All international electronic databases including Medline, Web of Sciences, Scopus, Cochran's library, EMBASE and Cancerlit will be searched to find randomized control trials which compared two or more treatment interventions for esophageal cancer. A network plot will be drawn for visual representation of all available treatment interventions. Bayesian approach will be used to combine the direct and indirect evidence. Treatment effects (e.g. hazard ratio for time to event outcomes, risk ratio for binary outcomes, and rate ratio for count outcomes with 95% credible interval) will be reported. Moreover, cumulative probability of the treatment ranks will be reported using the surface under the cumulative ranking (SUCRA) graphs. Consistency assumption will be assessed by the loop-specific and design-by-treatment interaction approaches. Conclusions: The results of this study may be helpful for the patients, clinicians and health policy makers in selecting treatments that have the best effect on survival and lowest adverse events.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1197-1203
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• 2014

Background: Adenocarcinoma (ADC) is the most common histological type of lung cancer and its proportion is rising, especially in Asian non-smoking women. Recent studies suggest miR-25 may have diverse effects on the pathogenesis of different types of cancer. However, the role of miR-25 in lung cancer is still unknown. The aim of this study was to investigate the potential clinical value of miR-25 in non-smoking women with lung ADC. Patients and Methods: Quantitative RT-PCR was performed to evaluate the expression of miR-25 in 100 lung ADC tumor tissues and matched plasma samples and Pearson correlation tests were used to analyze the relationship between values. Associations of miR-25 expression with clinicopathological features were determined using the Student's t-test. To determine prognostic value, overall survival (OS) was evaluated using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazard model. Results: Expression of miR-25 in tissue was found to be associated with lymph node metastasis (P=0.021) and disease stage (P=0.012). Moreover, high miR-25 expression was also associated with poorer overall survival of women with lung ADC (P=0.008). Conclusion: Tissue miR-25 expression may be associated with tumor progression and have prognostic implications in female lung ADC patients.