• Title/Summary/Keyword: bias effect

Search Result 1,482, Processing Time 0.027 seconds

Factors Related to Positive Psychological Capital among Korean Clinical Nurses: A Systematic Review and Meta-Analysis (국내 임상간호사의 긍정심리자본 관련 요인: 체계적 문헌고찰 및 메타분석)

  • Lee, Byung Yup;Jung, Hyang Mi
    • Journal of Korean Clinical Nursing Research
    • /
    • v.25 no.3
    • /
    • pp.221-236
    • /
    • 2019
  • Purpose: The purpose of this study was to systematically review and identify factors relevant to the positive psychological capital of clinical nurses. Methods: These was no limit on year of publication. Articles related to Korean clinical nurses were retrieved from computerized database using a manual search. A systematic review was conducted based on the PRISMA flow. The total correlational effect size (ESr) for each related factor was calculated from Fisher's Zr. Funnel plots, fail-safe numbers, and Egger regression tests were used to evaluate publication bias in meta-analysis studies. The correlational effect size of 25 studies was analyzed through meta-analysis using Comprehensive Meta-Analysis software 3.0 (CMA). Results: The review included 25 studies. In the systematic review, 14 demographic factors and 46 organizational factors were found to be influential. Eleven factors (6 demographic factors and 5 organizational factors) were appropriate for meta-analysis. The overall effect size was .26. The demographic total correlation effect size of related factors was .20 and the total effect size of organization was .46. Organizational commitment (ESr=.38) and job satisfaction (ESr=.54) were statistically positively related variables. Negative variables were burnout (ESr=-.61), turnover intention (ESr=-.41) and workplace bullying (ESr=-.33). The total effect size of the organizational factors was larger than the demographic total effect size. There was no publication bias except for demographic variables. Conclusion: Organizational factors and adjustable variables have a significant impact on positive psychological capital. The results of this study support the need for development of interventions focusing on organizational factors.

The Effectiveness of Non-pharmacological Interventions on Anxiety in Children Undergoing Surgery: A Systematic Review and Meta-analysis (수술 환아의 불안에 적용한 비약물적 중재의 효과: 체계적 문헌고찰 및 메타분석)

  • Kim, Hyeon-Young;Shin, Sun Hwa
    • Journal of East-West Nursing Research
    • /
    • v.27 no.1
    • /
    • pp.1-13
    • /
    • 2021
  • Purpose: The purpose of this study was to examine the effectiveness of non-pharmacological interventions for reducing perioperative anxiety in children undergoing surgery. Methods: A systematic review of randomized controlled trials (RCTs) with the primary outcome of children's perioperative anxiety was conducted. The literature search was performed using various databases, including Cochrane Library, CINAHL, EMBASE, PubMed, and Korean electronic databases with confined to RCTs between 2000 and 2020. A total of sixteen studies were suitable the inclusion criteria and were systematically reviewed. The bias risk of randomized studies was evaluated using Cochrane's risk of bias tool. For the meta-analysis, RevMan 5.4 was used to analyze effect sizes of interventional factors. Results: Finally, twelve RCTs studies were used for meta-analysis. The non-pharmacological interventions implemented to reduce perioperative anxiety in children were therapeutic play, clown therapy and information provision. First, therapeutic play had a significant effect on reducing preoperative anxiety, with an effect size of -1.46 (95% CI=-1.78~-1.14). Second, clown therapy had a significant effect on reducing preoperative anxiety, with an effect size of -0.97 (95% CI=-1.45~-0.49). Finally, the provision of information had a significant effect on reducing preoperative anxiety, with an effect size of -0.75 (95% CI=-0.99~-0.51). Conclusion: This meta-analysis suggests that non-pharmaceutical interventions provide effective methods of reducing perioperative anxiety in children. Therefore, the findings verify evidence that various non-pharmacological interventions are effective means for reducing children's preoperative anxiety.

Irreversible Charge Trapping at the Semiconductor/Polymer Interface of Organic Field-Effect Transistors (유기전계효과 트랜지스터의 반도체/고분자절연체 계면에 발생하는 비가역적 전하트래핑에 관한 연구)

  • Im, Jaemin;Choi, Hyun Ho
    • Journal of Adhesion and Interface
    • /
    • v.21 no.4
    • /
    • pp.129-134
    • /
    • 2020
  • Understanding charge trapping at the interface between conjugated semiconductor and polymer dielectric basically gives insight into the development of long-term stable organic field-effect transistors (OFET). Here, the charge transport properties of OFETs using polymer dielectric with various molecular weights (MWs) have been investigated. The conjugated semiconductor, pentacene exhibited morphology and crystallinity, insensitive to MWs of polymethyl methacrylate (PMMA) dielectric. Consequently, transfer curves and field-effect mobilities of as-prepared devices are independent of MWs. Under bias stress in humid environment, however, the drain current decay as well as transfer curve shift are found to increase as the MW of PMMA decreases (MW effect). The charge trapping induced by MW effect is irreversible, that is, the localized charges are difficult to be delocalized. The MW effect is caused by the variation in the density of polymer chain ends in the PMMA: the free volumes at the PMMA chain ends act as charge trap sites, corresponding to drain current decay depending on MWs of PMMA.

Effects of Manual Therapy on Musculoskeletal Diseases : A Meta-Analysis (근육뼈대계 질환에 대한 도수치료의 효과: 메타분석)

  • Lee, Jeong-Woo;Gong, Gwang-Sik;Kim, Dong-Yeon;Koh, Un
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.9 no.1
    • /
    • pp.203-217
    • /
    • 2021
  • Purpose: The purpose of this meta-analysis was to examine the high-level evidence of the effects of manual therapy on musculoskeletal diseases. Methods: Domestic databases were searched for studies that conducted clinical trials associated with manual therapy on chronic musculoskeletal diseases. A total of 591 studies published between 2005 and 2018 were identified, with 18 studies satisfying the inclusion data. The studies were classified according to patient, intervention, comparison, and outcome (PICO). The search outcomes were items associated with pain and physical function. The 18 studies included in the study were evaluated by using the R meta-analysis (version 4.0). The quality of 18 randomized control trials was evaluated by using the Cochrane risk of bias (ROB). The effect sizes were computed as the corrected standardized mean difference (SMD). Subgroup and meta-regression analyses were also used. Egger's regression test was carried out in order to analyze the publication bias. Cumulative meta-analysis and sensitivity analysis were also conducted in order to analyze the data error. Results: The following factors showed the large effect size of manual therapy on chronic musculoskeletal diseases: pain (Hedges's g = 2.66; 95% CI = 1.47 ~ 3.85), and physical function (Hedges's g = 2.15; 95% CI: 1.22 ~ 3.08). The subgroup analysis only showed a statistical difference in the type of manual therapy (pain) and outcome (physical function). No statistically significant difference was found in the meta-regression analysis. Publication bias was found in the data, but the results of the trim-and-fill method showed that such bias did not largely affect the obtained data. Furthermore, there were no data errors in the cumulative meta-analysis and sensitivity analysis. Conclusion: This study provides evidence for the effectiveness of manual therapy on chronic musculoskeletal diseases in pain and physical function. Subgroup analysis suggests that only the type of manual therapy for pain and the type of outcome for physical function differed in effect size.

Effects of Cognitive Behavioral Therapy on Attention Deficit Hyperactivity Disorder among School-aged Children in Korea: A Meta-Analysis (한국 학령기 ADHD 아동을 위한 인지행동중재의 효과 연구: 메타분석)

  • Park, Wan-Ju;Park, Shin-Jeong;Hwang, Sung-Dong
    • Journal of Korean Academy of Nursing
    • /
    • v.45 no.2
    • /
    • pp.169-182
    • /
    • 2015
  • Purpose: This study was a meta-analysis designed to identify effects of Cognitive Behavioral Therapy (CBT) interventions in alleviating main symptoms of Attention Deficit Hyperactivity Disorder (ADHD) among school-aged children in Korea. Methods: Examination of several databases including Research Information Sharing Service, Korean Studies Information Service System, Data Base Periodical Information Academic and hand-searched article references, resulted in identification of 1,298 studies done between 2000 and 2013 of which 21 met the inclusion criteria. Comprehensive Meta-Analysis version 2.0 was used to analyze effect sizes, explore possible causes of heterogeneity, and check publication bias with a funnel plot and its trim-and-fill analysis. Results: Overall effect size of CBT intervention was large (g=1.08) along with each outcome of self-control (g=1.26), lack of attention (g=1.02), social skills (g=0.92), and hyperactivity (g=0.92). For heterogeneity, moderator analysis was performed, but no significant differences were found between the RCT (Randomized Controlled Trials) group and the NRCT (Non RCT) group. Also, meta-regression was performed using sample size, number of sessions, and length of session as predictors, but no statistically significant moderators were found. Finally, a funnel plot along with trim-and-fill analysis was produced to check for publication bias, but no significant bias was detected. Conclusion: Based on these findings, there is clear evidence that CBT intervention has significant positive effects on the main symptoms of school-aged children suffering ADHD. Further research is needed to target diverse age groups with ADHD along with more RCT studies to improve the effectiveness of the CBT intervention.

Designing Revenue Sharing Contract for Irrational Newsvendors (소매상의 비합리성을 고려한 공급사슬의 수익 공유 계약 설계에 대한 연구)

  • Lee, Jung Min;Seo, Yong Won
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.41 no.2
    • /
    • pp.101-127
    • /
    • 2016
  • Irrational ordering decisions of supply chain members have been gaining growing importance in the area of supply chain management. Irrational ordering behaviors that deviate from the profit maximizing decisions in the newsvendor settings have observed with human experiments in recent research. These behaviors can be modeled with several typical decision bias elements. This bias in ordering decisions affects the performance of supply chain contracts designed based on the assumption that the supply chain members make optimal decisions, making it necessary to design supply chain contracts by considering the irrationality. The purpose of this research is to derive a method to design the revenue sharing contract that considers human irrationality in ordering decisions. This research considers a simple two-echelon supply chain consisting of one supplier and one retailer, where the supplier is assumed to be perfectly rational while the retailer making newsvendor type ordering decisions displays irrational ordering behaviors. Under this environment, this research analytically models the revenue sharing contract to maximize the total supply chain profit or the supplier's own profits while considering the three decision bias patterns of the retailer, which include the pull-to-center effect, the prospect theory, and the increased subjective sensitivity to the revenue sharing ratio. Irrationality parameters are measured through human experiments based on which and through numerical simulations, we showed that significant improvements in the supply chain performance can be achieved.

Organizational commitment and organizational creativity: The moderating effect of training motivation (정서적 몰입과 조직 창의성의 관계: 학습동기의 조절효과)

  • Shin, Soo-Young
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.10
    • /
    • pp.206-213
    • /
    • 2018
  • For sustainable management under uncertainty, organizations should explore factors influencing organizational creativity. This research examined affective commitment as the factor expected to increase organizational creativity. Clarifying the relationship between affective commitment and organizational creativity, we consider training motivation as a moderator. The participants in this empirical study were 472 employees and 64 firms' CEO to confirm hypotheses that training motivation make strengthen the positive relationship between affective commitment and organizational creativity. Results showed that organizational creativity was associated with affective commitment. Moreover, there was a moderating effect of training motivation on the relationship between organizational commitment and organizational creativity. This study attempted to avoid common method bias by using different sources such as CEO's response and employees' response. The implications for future research are discussed, including exploring the mechanism of organizational creativity and practice.

Effect of Insertion of Hf layer in Al oxide tunnel barrier on the properties of magnetic tunnel junctions (알루미늄 산화물 절연막에 하프늄의 첨가가 자기터널접합의 특성에 미치는 영향)

  • Lim, W.C.;Bae, J.Y.;Lee, T.D.;Park, B.G.
    • Journal of the Korean Magnetics Society
    • /
    • v.14 no.1
    • /
    • pp.13-17
    • /
    • 2004
  • We have investigated the effect of Hf insertion in the Al oxide tunnel barrier on the properties of magnetic tunnel junctions (MTJs). MTJs with Hf inserted barrier show the higher tunnel magnetoresistance (TMR) ratio and less temperature and bias voltage dependence of TMR than MTJs with a conventional Al$_2$O$_3$ barrier. The enhancement of TMR ratio and the reduction of the temperature and bias voltage dependence might be due to the reduction of defects in the barrier. Al-Hf oxide was formed by depositing Al and Hf simultaneously, and oxidizing the compound films. The TMR ratio of 36% was almost the same value as that with Hf inserted barrier. This implies that the inserted Hf layers mixed with Al layers during deposition or oxidation, and they might form Al Hf oxide barriers. This compound Al Hf oxide formation may be responsible to reduction of defect concentration which enhanced the TMR ratio and reduced temperature and bias-voltage dependence.

Socioeconomic Determinants of Korean Medicine Ambulatory Services: Comparing Panel Fixed Effect Model with Pooled Ordinary Least Square (한방외래의료 이용의 사회경제적 결정요인 연구: 의료패널자료를 이용한 고정효과모형과 합동 Ordinary Least Square 모형의 비교)

  • Park, Min Jung;Kwon, Soon Man
    • Health Policy and Management
    • /
    • v.24 no.1
    • /
    • pp.47-55
    • /
    • 2014
  • Background: Korea is considered to have an integrative health system where both western medicine and Korean (traditional) medicine are officially recognized and provided. Although Korean medicine has been covered by National Health Insurance over 20 years, equity in the utilization of Korean medical care has rarely been examined. Methods: We examined medical care utilization and expenditure of outpatient Korean medicine using panel fixed effects model to remove selection bias. Then we compared it with pooled ordinary least square (OLS) model. This study used Korea Health Panel data, which provides accurate information on out-of-pocket health care payment, including non-covered medical services. Results: Principal findings indicate that the frequency of the utilization of Korean medicine is related with unobservable individual choices different from western medicine, so the panel fixed effect model is appropriate. But pooled OLS model is better fitted for the expenditure of Korean medicine, after controlling for western medical care expenditure. After adjusting for the selection bias, socioeconomic status (income, education) was significantly associated with the expenditure of Korean medicine, but not with the frequency of the utilization of Korean medicine. Conclusion: This study shows that expenditure of Korean medicine utilization is inequitable across socioeconomic groups, which implies that health insurance coverage of Korean medicine is not sufficient.

Effect of Microstructure of hBN Thin Films on the Nucleation of cBN Phase Deposited by RF UBM Sputtering System (RF UBM Sputtering에 의해 증착된 hBN 박막의 미세구조가 cBN 상의 핵형성에 미치는 영향)

  • Lee Eun-Ok;Park Jong-Keuk;Lim Dae-Soon;Baik Young-Joon
    • Journal of the Korean Vacuum Society
    • /
    • v.13 no.4
    • /
    • pp.150-156
    • /
    • 2004
  • Boron nitride thin films were deposited on Si(100) substrate by RF (Radio-frequency) UBM (Unbalanced Magnetron) sputtering system. The effect of working pressure and substrate bias voltage on microstructure and compressive stress of boron nitride thin films has been investigated. In high working pressure, the alignment of hBN laminates increased with substrate bias voltage, in low working pressure, however, it was high in low substrate bias voltage. Compressive stress evolution and surface morphology of deposited BN films are closely related with the alignment of hBN laminates. The cBN phase without high compressive stress could be nucleated on hBN thin film by controlling the alignment of hBN laminates.