• Title/Summary/Keyword: meta-regression analysis

Search Result 158, Processing Time 0.031 seconds

Hyperlipidemia effect of garlic using mean difference of meta analysis (메타분석에서 평균차를 이용한 마늘의 항-고지혈증 효과)

  • Yun, A-Reum;Choi, Ki-Heon
    • Journal of the Korean Data and Information Science Society
    • /
    • v.22 no.3
    • /
    • pp.413-421
    • /
    • 2011
  • The present study was carried out to summarize the effect of garlic in the hyperlipidemia rats by meta-analysis related studies. The association measure to test effect of garlic was the mean difference (MD). In this particular fixed-effect model of mean difference, body weight, liver weight, kidney weight and heart weight were significantly decreased (p < 0.05). Also, blood glucose, plasma total cholesterol, plasma triglycerides, LDL-cholesterol, liver cholesterol, liver triglycerides were significantly decreased. HDL-cholesterol was significantly increased. In this case of heterogeneous variable, random effect model was applied. In this model, liver weight, blood glucose, plasma total cholesterol, plasma triglycerides, LDL-cholesterol, liver cholesterol, liver triglycerides were significantly decreased. HDL-cholesterol was significantly increased. According to the meta-regression analysis, duration of injection was significantly for kidney weight, testis weight, plasma total cholesterol, plasma triglycerides, HDL-cholesterol, LDLcholesterol, liver cholesterol, liver triglycerides.

Prognostic Value of β-catenin Expression in Breast Cancer Patients: a Meta-analysis

  • Zhang, De-Pu;Li, Xiao-Wei;Lang, Jing-He
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.14
    • /
    • pp.5625-5633
    • /
    • 2015
  • Background: ${\beta}$-catenin plays a crucial role in the progression of breast cancer (BC) and a prognostic role of in BC patients has been widely reported. However, controversy still remains. Materials and Methods: Identical search strategies were used to search relevant literature in electronic databases updated to July 1, 2014. Individual hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted and pooled HRs with 95%CIs were used to evaluate the strength of association between positive ${\beta}$-catenin expression in different subcellular locations and survival results of BC patients. Subgroup and meta-regression analyses were performed to explore heterogeneity. Funnel plots of Begg's and Egger's linear regression test were used to investigate publication bias. Heterogeneity and sensitivity were also assessed. All the work was completed using STATA. Results: A total of 2,204 patients from 12 evaluative studies were finally included. Pooled HRs and 95%CIs suggested that ${\beta}$-catenin expression in cytoplasm/nucleus had an unfavorable impact on both overall survival (OS) (HR: 1.93, 95%CI: 1.40-2.65) and disease free survival (DFS)/ recurrent free survival (RFS) (HR: 1.60, 95%CI: 1.20-2.13) in BC patients. However, here was no significant association between ${\beta}$-catenin expression in the membranes with OS (HR: 0.65, 95%CI: 0.42-1.02) or DFS/RFS (HR: 0.66, 95%CI: 0.38-1.13). Publication bias was absent in all of the four outcomes. Sensitivity analysis revealed that the results of this meta-analysis were robust. Conclusions: Positive ${\beta}$-catenin expression in cytoplasm/nucleus rather than in membrane is a significant prognostic factor in patients with BC who have been surgically treated.

Effects of Microcurrent on Inflammatory Musculoskeletal Diseases: A Meta-Analysis (염증성 근육뼈대계 질환에 대한 미세전류의 효과: 메타분석)

  • Lee, Jeongwoo;Ko, Un;Doo, Yeongtaek
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.8 no.4
    • /
    • pp.1-11
    • /
    • 2020
  • Purpose : The purpose of this meta-analysis was to examine the effects of microcurrent on inflammatory musculoskeletal diseases. Methods : Domestic databases (RISS, NDSL, KISS, DBpia, and Kmbase) were searched for studies that conducted clinical trials associated with microcurrent and its impact on inflammatory musculoskeletal diseases. A total of 606 studies published between 2002 and 2019 were identified, with 8 studies satisfying the inclusion data. The studies were classified according to patient, intervention, comparison, and outcome (PICO). The search outcomes were items associated with blood component, pain, and function. The 8 studies that were included in the study were evaluated using R meta-analysis (version 4.0). The quality of 7 randomized control trials was evaluated using Cochrane risk of bias (ROB). The quality of 1 non-randomized control trial was evaluated using risk of bias assessment tool for non-randomized studies (RoBANS). Effect sizes were computed as the corrected standard mean difference (SMD). A random-effect model was used to analyze the effect size because of the high heterogeneity among the studies. Egger's regression test was carried out to analyze the publishing bias. Results : The following factors had a large effect size involving microcurrent on inflammatory musculoskeletal diseases: blood component (Hedges's g=-2.46, 95 % CI=-4.20~-0.73), pain (Hedges's g=3.51, 95 % CI=2.44~4.77), and function (Hedges's g=3.06, 95 % CI: 1.53~4.58). Except for function (t=1.572, p=.191), Egger's regression test showed that the publishing bias had statistically significant differences. Conclusion : This study provides evidence for the effectiveness of microcurrent on inflammatory musculoskeletal diseases in terms of blood component, pain, and function. However, due to the small sample sizes used in the included studies, the results of our study should be interpreted cautiously, especially considering the publishing bias.

Periodontal health status, oral microbiome, white-spot lesions and oral health related to quality of life-clear aligners versus fixed appliances: A systematic review, meta-analysis and meta-regression

  • Ana Sandra Llera-Romero;Milagros Adobes-Martin;Jose Enrique Iranzo-Cortes;Jose Maria Montiel-Company;Daniele Garcovich
    • The korean journal of orthodontics
    • /
    • v.53 no.6
    • /
    • pp.374-392
    • /
    • 2023
  • Objective: Assess and evaluate the different indicators of oral health-related quality of life (OHRQoL) among patients treated with clear aligners (CAs) versus those treated with conventional fixed orthodontics (FAs). Methods: An electronic search was performed on the database is Web of Science, Scopus, and Embase databases. Randomized and non-randomized control trials, cross-sectional, prospective cohort and retrospective trials were included. Quality was assessed with risk of bias tool and risk of bias in non-randomised studies. Meta-analyses were performed with random effects models, estimating the standardized and non-standardized mean differences, odds ratio and risk ratio as the measure of effect. The effect on time was determined using a meta-regression model. Results: Thirty one articles were included in the qualitative synthesis and 17 in the meta-analysis. CAs had a significantly lower negative impact on QoL, with an "important" effect size, while the influence of time was not significant. Periodontal indicators plaque index (PI), gingival index (GI), probing depth (PD), and bleeding on probing show significantly better values in patients treated with CAs, with moderate to large effect sizes. PI and GI have a significant tendency to improve over time. In microbiological indicators, CAs present a lower biofilm mass without differences in the percentage of patients with high counts of Streptococcus mutans and Lactobacilli bacteria. The risk of white spot lesion onset is ten times lower in carriers of CAs. Conclusions: Patients wearing CAs show better periodontal indicators, less risk of white spot development, less biofilm mass and a better QoL than patients with FAs.

Lack of Association Between CYP1A1 Polymorphisms and Risk of Bladder Cancer: a Meta-analysis

  • Lu, Yu;Zhang, Xiao-Lian;Xie, Li;Li, Tai-Jie;He, Yu;Peng, Qi-Liu;Deng, Yan;Wang, Jian;Qin, Xue;Li, Shan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.9
    • /
    • pp.4071-4077
    • /
    • 2014
  • Background: The effects of CYP1A1 gene polymorphisms on the risk of bladder cancer (BC) remain controversial. We carried out a meta-analysis to clarify the role of CYP1A1 gene polymorphisms in BC. Material and Methods: A comprehensive literature search was conducted up to November 20, 2013. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of the association. Meta-regression, subgroup analysis, sensitivity analysis and publication bias were also performed. Results: Eight studies involving 1,059 BC cases and 1,061 controls were included. The meta-analysis showed that there was no significant association between the two common mutations of CYP1A1 and BC risk. For the I1e462Val A/G polymorphism with GG vs. AA the OR was 1.47 (95 % CI= 0.70-3.07, P =0.308). For the MspI T/C polymorphism, though a slight trend was found this was not statistically nonsignificant (CC vs.TT, OR = 1.24, 95 % CI= 0.98-1.58, P =0.078). Subgroup analyses by ethnicity also found no obvious association between CYP1A1 and BC risk. Conclusion: The present meta-analysis suggests that CYP1A1 polymorphism is not associated with bladder cancer risk.

Phytoestrogen Intake and Risk of Ovarian Cancer: a Meta-Analysis of 10 Observational Studies

  • Qu, Xin-Lan;Fang, Yuan;Zhang, Ming;Zhang, Yuan-Zhen
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.21
    • /
    • pp.9085-9091
    • /
    • 2014
  • Background: Epidemiology studies have shown an inconclusive relationship between phytoestrogen intake and ovarian cancer risk and there have been no relevant meta-analyses directly regarding this topic. The purpose of the present meta-analysis was therefore to investigate any association between phytoestrogen intake and ovarian cancer in detail. Materials and Methods: We conducted a search of PubMed, EMBASE, EBSCO, the Cochrane Library, CNKI and Chinese Biomedical Database (up to April 2014) using common keywords for studies that focused on phytoestrogen and ovarian cancer risk. Study-specific risk estimates (RRs) were pooled using fixed effect or random-effect models. Results: Ten epidemiologic studies were finally included in the meta-analysis. The total results indicated higher phytoestrogen intake was associated with a reduced ovarian cancer risk (RR, 0.70; 95%CI: 0.56-0.87). The association was similar in sensitivity analysis. Meta regression analysis demonstrated sources and possibly types and regions as heterogeneous factors. Subgroup analysis of types, sources and regions showed that isoflavones (RR: 0.63; 95%CI: 0.46, 0.86), soy foods (RR: 0.51; 95%CI: 0.39, 0.68) and an Asian diet (RR: 0.48; 95%CI: 0.37, 0.63) intake could reduce the incidence of ovarian cancer. Conclusions: Our findings show possible protection by phytoestrogens against ovarian cancer. We emphasize specific phytoestrogens from soy foods, but not all could reduce the risk. The habit of plentiful phytoestrogen intake by Asians is worthy to recommendation. However, we still need additional larger well designed observational studies to fully characterize underlying associations.

Meta-analysis on the Effects of Fashion Product Evaluation Attributes in Korea (국내 연구의 패션상품 평가속성 효과에 대한 메타분석연구)

  • Lee, Jung-Woo;Kim, Mi Young
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.40 no.6
    • /
    • pp.1150-1163
    • /
    • 2016
  • This study makes use of meta-analysis to statistically integrate the quantitative results of individual research on the influence of fashion product attributes on purchase; in addition, this study utilizes the effect sizes of correlation coefficients. This study was based on 24 individual studies from January 2000 to March 2015. The meta-analysis analyzed 91 effect sizes and 24 studies and calculated the correlation coefficient effect sizes. A random effect model was employed for meta-analysis because the results for the homogeneity test indicated that the effect sizes of each research were heterogeneous. The analysis results are as follows. First, when the total effect sizes of the fashion product attributes that influence clothing purchase decisions were calculated as .256; this indicated that the effect size is slightly below the mid-sized level. Second, upon examining the effect sizes of the categorized fashion product attributes, the intrinsic attributes yielded .222, extrinsic factors yielded .235, and the compiled attributes yielded .420; this demonstrated that the compiled attributes have a larger effect size than individual attributes. Third, when they were measured by the characteristics of study targets, they were larger for a mixed-gender group than women as well as for ordinary citizens than university students. When the effect sizes were measured based on the characteristics of fashion products as suggested in the study, there were significant differences with respect to sportswear, followed by SPA brand clothing, general clothing, fashion accessories, and designer clothing. The cases where the clothing were purchased in non-retail stores were found to have a slightly larger effect size than those of offline retail stores when the effect sizes were measured based on purchase routes; however, the difference was not statistically significant. Next, an investigation of the trend of effect sizes based on published year via the meta regression analysis indicated slightly larger effect sizes as shown in more recent publications, but this was not statistically significant.

A Meta-regression Analysis of the Variables Associated with the Job Satisfaction of Kindergarten Teachers (유치원교사의 직무만족과 관련된 변인에 대한 메타회귀분석)

  • Moon, Dong-Kyu
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.12
    • /
    • pp.242-252
    • /
    • 2016
  • This study seeks to verify the effect size of the variables relating to job satisfaction through a meta-analysis focusing on previous papers over the last 20 years that have examined the job satisfaction of kindergarten teachers and verified the trend by publication year through a meta-regression analysis. The study results are as follows. First, the results demonstrated that the total effect size of the variables relating to kindergarten teachers was large. Second, the organization's internal variable and organization's external variable groups, except for the individual characteristics variable group, showed a large effect size at similar levels. Third, the status of teachers in the individual characteristics variable group showed a meaningfully large effect size and the interpersonal relationship variable in organization's internal variable group showed a relatively larger effect size than the organizational climate variable did. Finally, the results of the verification of the trend by publication year showed that job satisfaction increased for all variables, except for the individual characteristics variable in more recent publications. This study highlights the imperative of making every effort to improve the organization's internal and external environment. In particular, measures to reduce job stress and work load are required. Furthermore, the atmosphere that is devoted to the teaching profession and teacher efficacy is important.

A Meta-regression Analysis on related Protective Variables of Childcare Teacher's Turnover Intentions (보육교사의 이직의도와 관련된 억제변인의 메타회귀분석)

  • Moon, Dong Kyu
    • Korean Journal of Childcare and Education
    • /
    • v.8 no.1
    • /
    • pp.25-44
    • /
    • 2012
  • The purpose of this study was to conduct a systematic review of the previous studies done on the child-care teacher's turnover intentions. From 2001 to 2011, 33 articles which reforted primary empirical data met the criteria for inclusion in the meta-analysis. The results of this study are as follo ws: First, included in the main factors related to child-care teachers' turnover intentions were a job-related variable, an organizational internal variable and an organizational external variable. Second, the most influential protective variable related to the child-care teacher's turnover intentions among the set of organizational external variables was work-time followed by welfare, education and training, remuneration, social recognition and promotion system. Third, the most influential protective variable related to child-care teachers' turnover intentions among the set of job-related variables was teacher efficacy followed by job satisfaction, participation of decision making, performance, work-autonomy and work-professionalism. Fourth, the most influential protective variable related to the child-care teacher's turnover intentions among the set of organizational internal variables was personal relations followed by relationships with the director and relationships with colleagues. The effect size of these variables was large. Fifth, the results of meta-regression analysis revealed that the survey area and years had no significant effect on overall effect sizes.

Effect of Cognitive Improvement Programs for Mild Cognitive Impairment in Korean Elderly: A Meta-Analysis (한국 경도인지장애 노인을 위한 인지기능 향상 프로그램의 효과: 메타분석)

  • Kim, Kyoungyun;Lee, Eunjoo
    • Korean Journal of Adult Nursing
    • /
    • v.29 no.2
    • /
    • pp.177-189
    • /
    • 2017
  • Purpose: A meta-analysis was conducted to identify the effect of cognitive improvement programs for the elderly with mild cognitive impairment (MCI) in Korea. Methods: Five databases, as well as relevant reference lists, of studies published from 2000 to 2016, were searched. Fourteen studies were identified. Quality assessments of included studies were conducted using the Scottish Intercollegiate Guidelines Network checklist. An R program was used to analyze effect sizes and to identify possible sources of heterogeneity among studies. The potential for publication bias was investigated using a funnel plot, Egger's regression test and sensitivity analysis. Results: The total effect size was large (Standardized Mean Difference [SMD]=1.44, 95% CI: 1.11~1.77), with cognition based intervention (SMD= 1.77, 95% CI: 1.26~2.29) and exercise intervention (SMD=1.13, 95% CI: 0.82~1.44). Statistically significant moderators were identified intervention type by meta-ANOVA analyses. Finally, no significant evidence of publication bias was found. Conclusion: There is clear evidence that cognitive improvement programs can greatly enhance cognition in elderly with MCI. Future research should examine the effects of non-pharmacological interventions targeting elderly populations with mild-to-severe cognitive impairment in order to develop and enhance the effectiveness of cognitive improvement programs in Korea.