• 제목/요약/키워드: bias effect

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Meta-analysis of the Effects of Obesity Management Program for Children (국내 비만아동의 비만관리프로그램의 효과에 대한 메타분석)

  • Sung, Kyung-Suk;Yoon, Young-Mi;Kim, Eun-Joo
    • Child Health Nursing Research
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    • v.19 no.4
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    • pp.262-269
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    • 2013
  • Purpose: The aims of this study is to analysis the effects of obesity management programs for children and to measure the differences in the effects by type and dependent variables in order to analyze the structures of the programs. Methods: Sixty-one peer-reviewed journals including child obesity and intervention studies published between 2000 and 2010 were included for meta-analysis. Effect size and statistics of homogeneity were by STAT 10.0. Results: A total of 61 studies were used in the analysis, and the effect size of the independent studies was determined to be -0.23 (95% CI, -0.32 ~ -0.15). Serum Leptin and Insulin were the big effect size among the studies that used dependent variables. The theses used in the research did not display publishing bias. Conclusion: Obesity management programs that have been confirmed to be effective need to be developed into regional protocols. A continuous control of obese children and research for effective intervention program are in need.

The Role of Relational Capital in Supply Chain Management for Distribution Service Firms (유통서비스 기업의 공급사슬 운영성과 경로에서 파트너 관계자산의 역할)

  • Cho, Yeon-Sung
    • Journal of Distribution Science
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    • v.13 no.11
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    • pp.111-121
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    • 2015
  • Purpose - This study's purpose is to investigate the impact of supply chain management (SCM) factors among targeted Korean distribution firms. Antecedents are established for supply chain orientation (SCO) for the management and organization of cultural assets. The research sets up SCO corresponding to management cultural assets and to organizational factors in the results. The research model is created to examine the SCO based on a strategic perspective and the operational performance of the SC and SCM. In addition, an integrated model is constructed to analyze the moderating effect by setting partner cooperation as a relational capital factor. The main aim of this study is to analyze the characteristics of the supply chain structure as a source of competitive advantage for distribution service firms participating in the supply chain. In the moderating effects analysis, the role of partner cooperation as relational capital is examined in detail. Research design, data, and methodology - The study examined the existing research related to supply chains, discussing the antecedents of the performance of SCM and SCO. SCM was established with the partner's cooperation as relational capital. Including the moderating effects of the partner cooperation, the research proposed a seven hypotheses path analysis model. The samples were collected from the Korean export enterprises in the distribution service sector, with 185 samples selected for the final analysis. To try and measure the four latent variables presented in the analysis model based on existing studies, 22 measurement items were used. The empirical analysis used the appropriate PLS (partial least squares) method on the path analysis reliability and validity and for common method bias. After testing the seven hypotheses, the research tested the moderating effects to the path analysis. Using PLS as structural equation modeling, the seven hypotheses were tested including the moderating effects of the partner relational capital on the 185 samples. Results - In the results, the SCO had a positive impact on both SCM and the relational capital of partner cooperation. The SCM had a significant impact on the operational performance of the SC. Further, partner cooperation also had a significant impact on SCM and the operational performance of the SC. The moderating effect analysis of the SCM and partner cooperation found a significant impact on the operational performance of the SC. On the other hand, the moderating effect of the SCO and partner cooperation did not affect the SCM. Conclusion - The results of this research show that the existing supply chain-related research can be applied to the operational performance of the SC for a Korean distribution service firm. In view of the fact that SCO is a source of competitive advantage, it should be taken into account when a firm wants to improve the performance of the SCM of the distribution service. This is because it can be assumed that SCO plays a role in supply chain management for the distribution firm.

Pretreatment Thrombocytosis as a Prognostic Factor in Women with Gynecologic Malignancies: a Meta-analysis

  • Yu, Min;Liu, Lei;Zhang, Bing-Lan;Chen, Qi;Ma, Xue-Lei;Wu, Yu-Ke;Liang, Chun-Shui;Niu, Zhi-Min;Qin, Xin;Niu, Ting
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6077-6081
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    • 2012
  • Background: This study was performed to analyze the prognostic implications of pretreatment or preoperative thrombocytosis in women with gynecologic malignancies. Material and Methods: We surveyed 2 medical databases, PubMed and EMBASE, to identified all relevant studies. A total of 14 (n=3,490) that evaluated the link between thrombocytosis and 5-year survival were included. REVMAN version 5.1 was used for our analysis and publication bias was evaluated using the Begg's funnel plot and tested by STATA 11.0. Risk ratios (RRs) with 95% confidence intervals (CIs) generated by the random effect model were used to assess the strength of any association. Results: 709(20.3%) of the 3,490 patients exhibited thrombocytosis (platelet counts > $400{\times}10^9/L$) at primary diagnosis, and their mortality was 1.62-fold higher compared with the others (RR=1.62, 95%CI=[1.28-2.05], p<0.0001). Thrombocytosis failed to have a stronger effect on the survival of advanced patients of stages III to IV in our study (n=478, RR=1.29, 95% CI=[1.13-1.48], p=0.0003), nor in women with cervical cancer in stage IB (n=1371, RR=1.73, 95% CI=[1.71-2.58], p=0.007). In addition, when adjusted for different carcinoma, it was associated with worse prognosis for all except the ones with vulvar cancer (n=201, RR=0.43, 95% CI=[0.14-1.29], p=0.13). Conclusions: This meta-analysis indicated that thrombocytosis might be associated with a worse prognosis for patients with gynecologic malignancies but without specificity or sensitivity for the ones in advanced stage. When adjusted for different gynecologic malignancies, it showed a significant effect on survival of all except vulvar cancers.

Vegetable Oil Intake and Breast Cancer Risk: a Meta-analysis

  • Xin, Yue;Li, Xiao-Yu;Sun, Shi-Ran;Wang, Li-Xia;Huang, Tao
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.12
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    • pp.5125-5135
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    • 2015
  • Background: Total fat intake may be associated with increased risk of breast cancer, and fish oil has been suggested as a protection factor to breast cancer. But the effect of vegetable oils is inconclusive. We aimed to investigate the association with high vegetable oils consumption and breast cancer risk, and evaluated their dose-response relationship. Design: We systematically searched the MEDLINE, EMBASE, Cochrane databases, and CNKI updated to December 2014, and identified all observational studies providing quantitative estimates between breast cancer risk and different vegetable oils consumption. Fixed or random effect models were used to estimate summary odds ratios for the highest vs. lowest intake, and dose-response relationship was assessed by restricted cubic spline model and generalized least-squares trend (GLST) model. Results: Five prospective cohort studies and 11 retrospective case-control studies, involving 11,161 breast cancer events from more than 150,000 females, met the inclusion criteria. Compared with the lowest vegetable oils consumption, higher intake didn't increased the risk of breast cancer with pooled OR of 0.88 (95% CIs:0.77-1.01), and the result from dose-response analyses didn't show a significant positive or negative trend on the breast cancer risk for each 10g vegetable oil/day increment (OR=0.98, 95% CIs: 0.95-1.01). In the subgroup analyses, the oils might impact on females with different strata of BMI. Higher olive oil intake showed a protective effect against breast cancer with OR of 0.74 (95% CIs: 0.60-0.92), which was not significant among the three cohort studies. Conclusions: This meta-analyses suggested that higher intake of vegetable oils is not associated with the higher risk of breast cancer. Olive oil might be a protective factor for the cancer occurrence among case-control studies and from the whole. Recall bias and imbalance in study location and vegetable oils subtypes shouldn't be ignored. More prospective cohort studies are required to confirm the interaction of the impact of vegetable oils on different population and various cancer characteristic, and further investigate the relationship between different subtype oils and breast cancer.

XRCC1 Gene Polymorphisms and Breast Cancer Risk: A Systematic Review and Meta-analysis Study

  • Moghaddam, Ali Sanjari;Nazarzadeh, Milad;Moghaddam, Hossein Sanjari;Bidel, Zeinab;Karamatinia, Aliasghar;Darvish, Hossein;Jarrahi, Alireza Mosavi
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup3
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    • pp.323-335
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    • 2016
  • Breast cancer risk assessment has developed during years and evaluation of genetic factor affecting risk of breast cancer is an important component of this risk assessment. The aim of this meta-analysis was to investigate the role of XRCC1 polymorphisms (Arg194Trp, Arg280His and Arg399Gln) in risk of breast cancer among different population and categories of menopausal status.PubMed, Medline, Web of Science, and PubMed Central were systematically searched to identify studies evaluating association between breast cancer and XRCC1 gene polymorphisms (Arg194Trp, Arg280His and Arg399Gln). Two authors independently extracted required information. Odds Ratios were pooled for four genetic inheritance models using both fixed and the DerSimonian and Laird random-effect models. Egger's test and contour-enhanced funnel plot was used to evaluate publication bias and small study effect. Additional subgroup analysis was performed for menopausal status, ethnicity, and source of controls. After evaluation and applying inclusion criteria on extracted studies, fifty three studies were included in this meta-analysis. For polymorphisms of Arg194Trp and Arg280His, no significant association was observed in all genetic models. Arg194Trp had a protective effect in post-menopausal status only in homozygote model (OR=0.57 [0.37-0.88]). Arg399Gln showed significant association with breast cancer in homozygote (OR=1.21 [1.10-1.34]), dominant (OR=1.09 [1.03-1.15]) and recessive (OR=1.21 [1.09- 1.35]) genetic models. Arg399Gln was associated with higher risk in post-menopausal status for homozygote and heterozygote models. Our findings suggest that XRCC1 gene polymorphisms modify breast cancer risk in different populations and different categories of menopausal status.

An Analysis of Policy Effects of Export Infrastructure Strengthening Program on Export of Food Distribution Companies (수출인프라강화사업이 식품유통기업 수출에 미치는 정책효과 분석)

  • Huang, Seong-Hyuk;Ji, Seong-Tae
    • Journal of Distribution Science
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    • v.16 no.1
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    • pp.87-99
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    • 2018
  • Purpose - The Export Infrastructure Strengthening Program(EISP) is a project to expand exports of agri-food products through providing customized export information to food distribution companies and supporting overseas information activities. A total of 39.6 billion won was provided by 2016. So, the purpose of this study is to analyze whether EISP is effective for expanding exports of agri-food products. Research design, data, and methodology - A simple average difference between the export performance of the policy beneficiaries and the non-policy beneficiaries can be biased if the export capacity or inherent characteristics of the enterprise are not taken into consideration. In order to solve the problem of such a bias, the propensity score matching(PSM) method has been employed in this study. PSM is a method of converting the characteristics of an export company into an index through logit analysis and then reducing the matching to one dimension to improve the accuracy of the performance measurement. Results - The balancing test was conducted to determine how the characteristics of the policy beneficiary group and the matched policy non-beneficiary group corresponded to each other. As a result of the test, we could not reject the null hypothesis that there was no difference between the two groups, so that after the matching, the two groups were similar and the explanatory variables were well controlled. Using the nearest neighbor matching with propensity score estimating through logit analysis, we estimated average treatment effect on the treated(ATT). The food companies participating the EISP had the effect of increasing the exports of $ 5.88 million. As a result, the number of export contracts increased by 11.77, the number of exporting countries by 7.52, the number of export items by 47.51, and the number of buyers' consultation by 3.50. And overseas marketing expenses increased by 35.92 million won. Except for the number of export contracts, other export performance results showed statistically significant results. Conclusions - As the EISP has a positive effect on the expansion of agro-food exports, efforts should be made to find out the limitations or problems of the policy in the future and to make a greater contribution to the increase of exports.

The effect of walnut (Juglans regia L.) intake on improvement of blood lipid levels and vascular health: A meta-analysis (호두의 혈중 지질 수준 및 혈관 건강 개선 기능성 평가: 메타분석)

  • Kwak, Jin Sook;Park, Min Young;Kwon, Oran
    • Journal of Nutrition and Health
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    • v.47 no.4
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    • pp.236-246
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    • 2014
  • Purpose: Walnut is known to have unique favorable fatty acids, phytochemicals, and other nutrient profiles. As a result, there has been growing interest in evaluation of its health benefit related to cardiovascular disease (CVD). Although inverse associations of nut consumption and risk factors of cardiovascular disease have been reported in many epidemiological studies and qualitative reviews, few meta-analysis studies have been reported. This meta-analysis was conducted in order to evaluate the effect of a walnut-enhanced diet on CVD risk factors. Methods: We searched Pubmed, Cochrane, Science Direct, and KISS (Korean studies Information Service System) through July 2014. A random-effects meta-analysis was conducted on 17 trials reporting total cholesterol (TC), 14 trials reporting LDL cholesterol (LDL-C), 15 trials reporting HDL cholesterol (HDL-C), 17 trials reporting triglyceride (TG), and four trials reporting flow-mediated dilation (FMD). Results: In meta-analysis, intake of a walnut-enhanced diet resulted in significantly lowered TC, LDL-C, and TG by -0.124 mmol/l (95% CI, -0.209, -0.039; p = 0.004), -0.085 mmol/lL (95% CI, -0.167, -0.004; p = l0.039), and -0.080 mmol/l (95% CI, -0.155, -0.004; p = 0.039), respectively. The overall pooled estimate of the effect on FMD was +1.313% (95% CI, 0.744, 1.882, p = 0.000). HDL-C was not affected by walnut intake. No statistical heterogeneity was observed for any analysis. Results of funnel plots and Egger's regression suggested a low likelihood of publication bias in all biomarkers (p > 0.05). Conclusion: Findings of this meta-analysis provide consistent evidence that walnut-enhanced diet intake reduces the CVD risk factors.

Effect of Acupuncture on Sciatica in Rat Models: Systematic Review and Meta-analysis (좌골신경통 백서모델에서 침치료의 효과: 체계적 문헌고찰 및 메타분석)

  • Yoon, Ye-Ji;Kim, Soojeon;Cho, Jae-Heung;Kim, Koh-Woon;Song, Mi-Yeon
    • Journal of Korean Medicine Rehabilitation
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    • v.30 no.1
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    • pp.79-93
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    • 2020
  • Objectives While sciatic neuropathy is one of the common symptoms which have the lifetime incidence of 13~40%, still there is no consensus about the standardized and the most effective conservative treatment. In addition, the importance of systematic review and meta-analysis of preclinical are growing as they could suggest possible effective treatment strategy for future studies. Therefore, we conducted systematic review and meta-analysis to estimate analgesic effect of acupuncture on sciatica in rat models. Methods Systematic search was conducted for all controlled comparative preclinical trials which assessed analgesic effect of acupuncture in sciatica rat models. Database of PubMed, EMBASE, Web of Science, CNKI and 6 Korean databases were used. The primary outcome was pain, which is evaluated by stimulus behavior tests in rat models. We assessed the methodological quality with Systematic Review Centre for Laboratory Animal Experimentation's risk of bias tool. RevMan 5.3 was used for meta-analysis and subgroup analysis was conducted according to treatment site, acupuncture point, treatment period and frequency used in electroacupuncture. Results 14 studies were finally included following our inclusion criteria. The data from meta-analysis indicated that the acupuncture significantly improved the result values of behavior tests for pain evaluation, compared to no-treatment control group in animal models (standardized mean difference=4.43, 95% confidence interval 3.16 to 5.69, Z=6.84, p<0.00001; χ2=68.02, p<0.00001; I2=82%). The results of subgroup analysis indicate that acupuncture treatment of unilateral site, distal acupoints, longer treatment period and applying 2/100 Hz frequency in electroacupuncture could be more effective. Conclusions Systematic review and meta-analysis of animal studies are getting important for the future clinical studies and the improvement of heatlh care. Therefore the results of the study would provide evidence and better design for the forthcoming studies.

The Impact of Human Resource Development on Job Satisfaction and Organizational Commitment : Mediating Effects of Learning Culture (인적자원개발제도, 조직몰입, 직무만족 간의 관계 : 조직수준의 학습문화의 매개효과 검증)

  • Kim, Sung Hwan
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.3
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    • pp.119-128
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    • 2014
  • One of the theoretically and empirically grounded black boxes in HRD and firm performance link is employee' attitudes such as organizational commitment and job satisfaction. However, most studies were conducted with the regression analysis at the organizational level. This study used HLM(hierarchical linear modeling) analysis, which made it possible to estimate more accurate relationship between variables that were measured from two different levels. In addition, this study attempted to open an the black box(learning culture) in the relationship between HRD and employee attitudes. The result showed that the HRD have a positive effect on the organizational commitment and the job satisfaction. Also the HRD showed full mediation effect of organization commitment and the job satisfaction on the Learning culture. And the result showed that the HRD in 2007 have a positive effect on employee' attitudes in 2009. These findings concluded that systematic HRD like employee's education and training must be built and also the positive culture for employee's learning like support of management's learning organization must be improved in order to promote the organizational performance(organizational commitment, job satisfaction) in company.

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A study on Ability and Utilization of Smart Devices for the Disabled: Focusing on the Effect of Education for Smart Device Utilization (장애인의 스마트기기 사용능력 및 활용도에 관한 연구 - 스마트기기 활용교육의 효과를 중심으로 -)

  • Song, Jihyang;Kim, Dongwook
    • Informatization Policy
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    • v.21 no.2
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    • pp.67-88
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    • 2014
  • The research hypothesis of this paper is that education for smart device utilization has a positive effect on ability and utilization of smart devices for the disabled. The data for disabled of NIA's 2012 survey about digital divide is used, and the research method is "Heckman's 2-stage method" which considers the problem of selection bias. As a research result, this paper says that the disabled who had experience of education for smart device utilization have higher level of ability and utilization of smart devices. Also, a high level of education and family income, professional career and young generation have been very positive effect on the high level of ability and utilization of the disabled. The level of ability and utilization of the blind tend to be lower than those of the physically disabled. These results remind that the education for smart device utilization for the disabled is important and effective. And various contents and methods of education which are appropriate for the disability types should be developed.