• 제목/요약/키워드: systematic bias

검색결과 658건 처리시간 0.025초

월경전증후군에 대한 한약 치료의 효과 : 체계적 문헌 고찰과 메타 분석 (Herbal Medicine for Premenstrual Syndrome: A Systematic Review and Meta-analysis)

  • 서지인;이윤재;고서림;김누리;김정훈;손미주;김영은;김안나;이은희
    • 대한한방부인과학회지
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    • 제36권4호
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    • pp.96-120
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    • 2023
  • Objectives: This study reports the findings that support the efficacy of herbal medicine (HM) for premenstrual syndrome (PMS). Methods: We conducted meta-analysis of findings from randomized controlled trials (RCTs) for PMS treated with HM. The articles were published before July 2022, located using 9 databases (Pubmed, EMBASE, Cochrane Library, CINAHL, CNKI, CiNii, SCIENCE ON, KoreaMed, OASIS). Results: We observed 2,034 studies, of which 23 RCTs met our inclusion criteria. The risk of bias in the included studies was relatively unclear or high. Meta-analysis of 3 RCTs showed that HM group had a significantly higher total effective rate than the western medicine group (RR 1.20 [95% CI 1.06, 1.36, p=0.004]). Meta-analysis of 1 RCT showed that HM group had a significantly lower symptom score (MD -3.04 [95% CI -5.36, -0.72, p=0.01]), while there was no significant difference in daily record of severity of problems scale (MD -20.52 [95% CI -49.33, 8.29, p=0.16]). Conclusions: HM significantly improved PMS symptoms than general treatment and no serious adverse events were reported. However, the evidence on the effectiveness and safety of HM for PMS was not enough to provide reliable results due to the small number and low quality of included studies. We believe that rigorous RCTs will lead to more reliable evidence of the intervention.

Prognostic Value of Vascular Endothelial Growth Factor Expression in Patients with Prostate Cancer: a Systematic Review with Meta-analysis

  • Wang, Kai;Peng, Hong-Ling;Li, Long-Kun
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권11호
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    • pp.5665-5669
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    • 2012
  • Background: The vascular endothelial growth factor (VEGF) mediates vasculogenesis and angiogenesis through promoting endothelial cell growth, migration and mitosis, and has involvement in cancer pathogenesis, progression and metastasis. However, the prognostic value of VEGF in patients with prostate cancer remains controversial. Objectives: The aim of our study was to evaluate the prognostic value of VEGF in prostate cancer, and summarise the results of related research on VEGF. Methods: In accordance with an established search strategy, 11 studies with 1,529 patients were included in our meta-analysis. The correlation of VEGF-expression with overall survival and progression-free survival was evaluated by hazard ratio, either given or calculated. Results: The studies were categorized by introduction of the author, demographic data in each study, prostate cancer-relatived information, VEGF cut-off value, VEGF subtype, methods of hazard ratio (HR) estimation and its 95% confidence interval (CI). High VEGF-expression in prostate cancer is a poor prognostic factor with statistical significance for OS (HR=2.32, 95%CI: 1.40-3.24). However, high VEGF-expression showed no effect on poor PFS (HR=1.30, 95%CI: 0.88-1.72). Using Begg's, Egger's test and funnel plots, we confirmed lack of publication bias in our analysis. Conclusion: VEGF might be regarded as a prognostic maker for prostate cancer, as supported by our meta-analysis. To achieve a more definitive conclusion enabling the clinical use of VEGF in prostate cancer, we need more high-quality interventional original studies following agreed research approaches or standards.

원발성 월경통의 전침 치료 연구에 관한 체계적 문헌 고찰 (Electroacupuncture for Treatment of Primary Dysmenorrhea: Systematic Review of Randomized Controlled Trials)

  • 박남춘;강나훈;유은실;이진욱;윤준걸;이진무;이창훈;장준복;황덕상
    • 대한한방부인과학회지
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    • 제30권2호
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    • pp.81-92
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    • 2017
  • Objectives: This review aims to report the efficacy and safety of electroacupuncture in the treatment of primary dysmenorrhea. Methods: We searched for randomized controlled studies (RCTs) using electroacupuncture on primary dysmenorrhea up to Dec 2016. The following databases were searched : OASIS, PubMED, EMBASE, CENTRAL. The results of the studies were analyzed and the risk of bias was assessed. Results: Five studies were included in this review. In most studies, the effect of electroacupuncture at Sameumgyo (SP6) was better than that of electroacupuncture at Hyeonjong (GB39), nonacupoint and no intervention about Visual analog scale (VAS), Verbal rating scale (VRS) and Retrospective symptom scale (RSS). But there were no significant effects on Resistance Index (RI) and S/D ratio (the ratio between peak systolic to end-diastolic flow velocity in uterine arteries). Serous adverse events were not reported. Conclusions: This review shows that electroacupuncture is effective on primary dysmenorrhea with no serious adverse events.

환자군 연구(Case series) 및 점검(Audit) 연구의 수행과 보고;저자를 위한 지침서 (Conducting and reporting case series and audits;author guidelines)

  • 김송이;김상우;이향숙;박히준
    • Korean Journal of Acupuncture
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    • 제24권4호
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    • pp.13-24
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    • 2007
  • Objectives : This article aims to give guidance on the conduct and reporting of case series and audits of acupuncture, based on common problems that have arisen in the past. This type of project, and particularly the prospective case series or pre- post-intervention study, may give valuable evidence of the overall effectiveness of acupuncture-for example in different situations and in different conditions- and provides one step in the research pathway before generating an hypothesis. Results & Discussion : The project should be designed with the aim of reducing bias as much as possible. Careful and detailed planning is essential for the project to produce worthwhile results that readers can evaluate and replicate. Ethical issues should be considered and formal approval may be necessary. The patient group should be recruited systematically and baseline data obtained. The treatment given should be systematic and decisions to change or end treatment made explicit. The outcome should be measured in ways that are known to be reliable and valid. Musculoskeletal problems can be evaluated with scales for pain and confirmed by measuring one other symptom such as stiffness or one other aspect such as bothersomeness. Global change scores also provide supporting information, and the MYMOP (Measure Yourself Medical Outcome Profile) measure is popular when patients with different conditions are included. The design of questionnaires for beliefs and attitudes is a specialised area that should not be attempted without expert help. Adverse events should also be recorded. Analysis of the data and the best way of summarising and presenting the results are also discussed.

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Protected versus Unprotected Carotid Artery Stenting : Meta-Analysis of the Current Literature

  • Cho, Young Dae;Kim, Sung-Eun;Lim, Jeong Wook;Choi, Hyuk Jai;Cho, Yong Jun;Jeon, Jin Pyeong
    • Journal of Korean Neurosurgical Society
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    • 제61권4호
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    • pp.458-466
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    • 2018
  • Objective : To compare peri-operative any symptomatic stroke after carotid angioplasty and stenting (CAS), based on the application or absence of a cerebral protection device. Methods : A systematic literature review using PubMed, Embase, and the Cochrane Central was done across an online data base from January 1995 to October 2016. Procedures which were performed due to carotid dissection or aneurysm, procedures using covered stents or conducted in an emergency, were excluded. The primary endpoint was perioperative any symptomatic stroke within 30 days after the procedure. A fixed effect model was used in cases of heterogeneity less than 50%. Results : In the 25 articles included in this study, the number of stroke events was 326 (2.0%) in protected CAS and 142 (3.4%) in unprotected CAS. The use of cerebral protection device significantly decreased stroke after CAS (odds ratio [OR] 0.633, 95% confidence interval [CI] 0.479-0.837, p=0.001). In the publication bias analysis, Egger's regression test disclosed that the intercept was -0.317 (95% CI -1.015-0.382, p=0.358). Regarding symptomatic patients (four studies, 539 CAS procedures), the number of stroke was six (1.7%) in protected CAS and 11 (5.7%) in unprotected CAS. The protective effect against stroke events by cerebral protection device did not have a statistical significance (OR 0.455, 95% CI 0.151-1.366, p=0.160). Conclusion : The use of protection device significantly decreased stroke after CAS. However, its efficacy was not demonstrated in symptomatic patients. Routine use of protection device during CAS should be critically assessed before mandatory use.

겨울철 동아시아 지역 기온의 계절 예측에 눈깊이 초기화가 미치는 영향 (Impact of Snow Depth Initialization on Seasonal Prediction of Surface Air Temperature over East Asia for Winter Season)

  • 우성호;정지훈;김백민;김성중
    • 대기
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    • 제22권1호
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    • pp.117-128
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    • 2012
  • Does snow depth initialization have a quantitative impact on sub-seasonal to seasonal prediction skill? To answer this question, a snow depth initialization technique for seasonal forecast system has been implemented and the impact of the initialization on the seasonal forecast of surface air temperature during the wintertime is examined. Since the snow depth observation can not be directly used in the model simulation due to the large systematic bias and much smaller model variability, an anomaly rescaling method to the snow depth initialization is applied. Snow depth in the model is initialized by adding a rescaled snow depth observation anomaly to the model snow depth climatology. A suite of seasonal forecast is performed for each year in recent 12 years (1999-2010) with and without the snow depth initialization to evaluate the performance of the developed technique. The results show that the seasonal forecast of surface air temperature over East Asian region sensitively depends on the initial snow depth anomaly over the region. However, the sensitivity shows large differences for different timing of the initialization and forecast lead time. Especially, the snow depth anomaly initialized in the late winter (Mar. 1) is the most effective in modulating the surface air temperature anomaly after one month. The real predictability gained by the snow depth initialization is also examined from the comparison with observation. The gain of the real predictability is generally small except for the forecasting experiment in the early winter (Nov. 1), which shows some skillful forecasts. Implications of these results and future directions for further development are discussed.

동아시아 여름 강수 모의에 있어 한반도 주변 해륙분포가 미치는 영향 (Impacts of the Land-sea Distribution around Korean Peninsula on the simulation of East Asia Summer Precipitation)

  • 차유미;이효신;권원태;부경온
    • 대기
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    • 제17권3호
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    • pp.241-253
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    • 2007
  • This paper investigates summer precipitation change in East Asia according to switching surface boundary condition over South Korea and Shantung. Simulations are carried out by ECHO-G/S for 20 years (1980-1999). Surface condition over both areas in ECHO-G/S is represented by ocean (OCN experiment). In OCN experiment, the summer precipitation is considerably underestimated around the Korean peninsula (the dry region) and overestimated over the eastern Tibetan Plateau (the wet region). It may be related that the lack of the heat sources from the unrealistically prescribed land-sea mask weakens northward expansion of rainband and the development of convective precipitation. Moreover the simulated rainband retreats before June in connection with the early genesis of summer monsoon circulation. The systematic bias of the summer precipitation over the dry and wet regions are reduced comparing with the OCN experiment when the land-sea masks over South Korea and Shantung are realistically considered as land (LND experiment). These improvements can be explained by the thermodynamical dissimilarity between land and ocean. Enhanced warming by switching the areas from sea to land has led to develop the thermal low over Yellow Sea with the cyclonic circulation. Thus, this cyclonic circulation supports moistures from the south to the dry region and blocks to the wet region. The heat transport from the land surface to atmosphere plays a key role in the developing convective precipitation in local scale and maintaining the precipitation and the rainband. Therefore, this results indicate that the design of the realistic land-sea distribution is required for the accurate simulation of the regional precipitation.

동아시아 지역의 AERONET 관측자료를 이용한 천리안 위성 기상탑재체의 에어로솔 광학두께 산출물의 검증 (Validation of COMS/MI Aerosol Optical Depth Products Using Aerosol Robotic Network (AERONET) Observations Over East Asia)

  • 이권호
    • 대한원격탐사학회지
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    • 제34권3호
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    • pp.507-517
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    • 2018
  • 천리안 위성(Communication, Ocean and Meteorological Satellite, COMS)의 에어로솔 광학두께(Aerosol Optical Depth; AOD) 산출물의 검증을 위하여, 동아시아 지역을 대상으로 2011년 1월부터 2014년 7월까지 산출자료와 134개의 지상관측 Aerosol Robotic Network(AERONET) AOD와 비교 분석하였다. 시공간 일치법을 사용하여 천리안 위성 AOD와 AERONET 전체 관측 지점의 AOD의 비교결과는 약한 상관관계(R=0.297)와 함께 천리안 AOD가 과대평가된 결과를 나타내었다. 그러나, AERONET 관측지점별 비교 결과는 각 지점별로 상이한 결과를 나타내었으며, 최소 상관계수 R=0.026(AOE_Baotou 지점) 과 최대 상관계수 R=0.905(DRAGON_Anmyeon 지점)을 보였다. 천리안 AOD와 AERONET AOD의 편차와 입자 유효반경, 수증기, 지표반사도, 태양천정각과의 비교결과, 천리안 AOD 산출물에 대한 계통적 오차가 발견되지 않았다. 그러나 한반도 인근지역의 한정된 지역을 대상으로 하면 천리안 AOD와 AERONET AOD의 유사성이 나타나므로, 지역적인 한계가 있음을 발견하였다. 마지막으로, 본 연구 결과는 COMS AOD 산출 알고리즘의 개선에 도움을 줄 수 있을 것이며, 따라서 개선된 비교검증 결과를 얻을 수 있을 것이다.

고혈압에 대한 한약 이수 처방 효과에 대한 체계적 문헌 고찰 및 메타분석 (The Effect of Korean Herbal Medicine that Function by Inducing Diuresis for Hypertension: Systematic Review and Meta-Analysis of Randomized Controlled Trials)

  • 강자연;강기완;정민정;김홍준;장인수
    • 대한한방내과학회지
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    • 제38권6호
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    • pp.902-916
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    • 2017
  • Objectives: The aim of this study was to review the clinical research on antihypertensive effects of Korean herbal medicines that function by inducing diuresis. Methods: Literature searches were performed using PubMed, Cochrane, CNKI, Wanfang, Cinii, Oasis, KISS, NDSL, RISS, DBPia, with the keywords "利水", "利尿", "高血壓", "hypertension", and "lishui." The search range included only randomized controlled trials that verified the effects of Korean herbal medicine interventions on hypertension. The selected studies were assessed by risk of bias (RoB). Results: 26 reports were selected from a total of 532 identified. For these reports, meta-analysis was performed using Revman 5.3. From this analysis, it was observed that the combined treatment of Korean medicine and antihypertensive drugs had a significantly higher total effective rate (TER) and improvement in systolic blood pressure (SBP) and diastolic blood pressure (DBP) than did the use of a single antihypertensive drug. The risk ratio of TER for lowering blood pressure was 1.25. The mean differences of SBP, DBP were -19.63 mm Hg (95% confidential interval (CI), -22.45 mm Hg, -16.80 mm Hg, p<0.00001), and -5.39 mm Hg (95% CI, -7.36 mm Hg, -3.42 mm Hg, p<0.00001) respectively. The use of Korean medicine only did not improve blood pressure, as compared to the use of an antihypertensive drug. Most of items of RoB were unclear, and the methodological quality was low. Conclusions: The combination of antihypertensive drugs and Korean medical treatment can effectively improve SBP, DBP, and TER. This finding could be widely utilized in clinical practice in Korean medicine.

Association between the TP53BP1 rs2602141 A/C Polymorphism and Cancer Risk: A Systematic Review and Meta-Analysis

  • Liu, Lei;Zhang, Dong;Jiao, Jing-Hua;Wang, Yu;Wu, Jing-Yang;Huang, De-Sheng
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권6호
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    • pp.2917-2922
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    • 2014
  • Background: The p53-binding protein 1 (TP53BP1) gene may be involved in the development of cancer through disrupting DNA repair. However, investigation of associations between TP53BP1 rs2602141 A/C polymorphism and cancer have yielded contradictory and inconclusive outcomes. We therefore performed a meta-analysis to evaluate the association between the TP53BP1 rs2602141 A/C polymorphism and cancer susceptibility. Materials and Methods: Published literature from PubMed, Medline, the Cochrane Library, EMbase, Web of Science, Google (scholar), CBMDisc, Chongqing VIP database, and CNKI database were retrieved. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using fixed or random-effects models. Publication bias was estimated using funnel plots, Begg's and Egger's test. Results: A total of seven studies (3,018 cases and 5,548 controls) were included in the meta-analysis. Our results showed that the genotype distribution of TP53BP1 rs2602141 A/C was not associated with cancer risk overall. However, on subgroup analysis, we found that TP53BP1 rs2602141 A/C was associated with cancer risk within an allele model (A vs C, OR=1.14, 95%CI: 1.01-1.29) and a codominant model (AA vs CC, OR=1.36, 95%CI: 1.06-1.74) in Asians rather than in Caucasians. Subgroup analysis by cancer type, genotype, and with or without adjustment for controls showed no significant association. Conclusions: The findings suggested an association between rs2602141 A/C polymorphism in TP53BP1 gene and increased risk of cancer in Asians.