• 제목/요약/키워드: Cox's regression

검색결과 156건 처리시간 0.034초

Survey of the use of statistical methods in Journal of the Korean Association of Oral and Maxillofacial Surgeons

  • Choi, Yong-Geun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • 제44권1호
    • /
    • pp.25-28
    • /
    • 2018
  • Objectives: This study aimed to describe recent patterns in the types of statistical test used in original articles that were published in Journal of the Korean Association of Oral and Maxillofacial Surgeons. Materials and Methods: Thirty-six original articles published in the Journal in 2015 and 2016 were ascertained. The type of statistical test was identified by one researcher. Descriptive statistics, such as frequency, rank, and proportion, were calculated. Graphical statistics, such as a histogram, were constructed to reveal the overall utilization pattern of statistical test types. Results: Twenty-two types of statistical test were used. Statistical test type was not reported in four original articles and classified as unclear in 5%. The four most frequently used statistical tests constituted 47% of the total tests and these were the chi-square test, Student's t-test, Fisher's exact test, and Mann-Whitney test in descending order. Regression models, such as the Cox proportional hazard model and multiple logistic regression to adjust for potential confounding variables, were used in only 6% of the studies. Normality tests, including the Kolmogorov-Smirnov test, Levene test, Shapiro-Wilk test, and $Scheff{\acute{e}}^{\prime}s$ test, were used diversely but in only 10% of the studies. Conclusion: A total of 22 statistical tests were identified, with four tests occupying almost half of the results. Adoption of a nonparametric test is recommended when the status of normality is vague. Adjustment for confounding variables should be pursued using a multiple regression model when the number of potential confounding variables is numerous.

말기암환자의 여명 예측 요인, 혈중 렙틴 농도의 효과 (Prognostic Value of Leptin in Terminally Ill Cancer Patients)

  • 홍지현;이소진;곽상미;최윤선;이준영
    • Journal of Hospice and Palliative Care
    • /
    • 제15권2호
    • /
    • pp.99-107
    • /
    • 2012
  • 목적: 말기암환자의 여명 예측은 치료의 이득과 위해를 판단하는 잣대가 되고, 적절한 의료 중재 제공 및 환자의 자율성에 기초한 의사결정에 중요한 기준이 된다. 특히 많은 수의 말기암환자는 암성 식욕부진-악액질 증후군으로 사망에 이르기 때문에 본 연구에서는 이를 반영할 수 있는 혈장 렙틴 농도와 생존기간과의 연관성을 알아보고자 하였다. 방법: 2009년 7월부터 2010년 7월까지 13개월 동안, 만 20세 이상의 말기암환자 69명을 대상으로 혈장 렙틴 농도를 측정하고, 생존기간을 조사하였다. 나이, 성별, 원발암 부위, 암 치료 경력, 전이여부, 투약상황 및 활력증후, 백혈구 수, 혈색소, Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), C-반응성 단백질, 총 빌리루빈, 총 콜레스테롤, 알부민, 렙틴 등의 혈액검사를 시행하였다. 결과: 혈장 렙틴 농도와 성별, 나이, 백혈구 수, 혈색소, AST, ALT, 총 빌리루빈, C-반응성 단백질, 통증강도 등의 상관 관계 분석 결과 렙틴과 생존기간에는 통계적으로 유의한 양의 상관 관계를 보였으며, 단변량 분석한 결과 혈장 렙틴 농도는 생존기간과 통계적으로 경계수준의 유의한 관계를 보였으나, 단변량 분석에서 생존 기간에 유의한 영향을 미치는 성별, 백혈구 수, AST, ALT, 총 빌리루빈, 알부민, C-반응성 단백질을 포함하여 시행한 다변량 분석에서 혈장 렙틴 농도는 생존기간과 통계적으로 유의한 관계가 없는 것으로 나타났다. 결론: 암성 식욕부진-악액질 증후군과 관련이 있는 혈장 렙틴 농도와 말기암환자의 생존기간과는 통계적으로 유의한 연관성을 보이지는 않았다. 그러나, 소화기계암환자에 있어서는 혈장 렙틴 농도가 생존기간 예측인자로서 쓰일 수 있는 가능성을 보여주었다.

여성의 이혼선택 요인에 관한 종단 연구: 생존분석을 중심으로 (Longitudinal Study on the Major Factors Affecting Divorce Choices among Women: Focused on Survival Analysis)

  • 박수선;박태영
    • 가족자원경영과 정책
    • /
    • 제26권3호
    • /
    • pp.65-85
    • /
    • 2022
  • 본 연구는 결혼생활에서 시간경과에 따라 여성이 이혼을 선택하게 만드는 영향 요인을 파악하여, 여성의 결혼과 이혼양상을 가족전환의 관점으로 이해하고 두 집단 모두 의미 있는 선택이 될 수 있도록 실천에 기반한 생활복지 차원의 성장에 기여하는데 목적이 있다. 이를 위해 본 연구는 여성가족패널 자료를 사용하여 생존분석 방법을 이용한 종단 연구를 시행하였다. 여성의 결혼생활에서 각 요인들이 이혼 선택에 어떤 영향을 미치는지 콕스회귀분석을 실시하여 세 가지 분석모형을 통해 파악한 결과 모든 모형이 분석에 적합한 것으로 나타났다.

혈액내과 입원 환자의 낙상 위험 요인과 환자 결과: 전자의무기록 분석 (Triggers and Outcomes of Falls in Hematology Patients: Analysis of Electronic Health Records)

  • 정민경;이선미
    • 기본간호학회지
    • /
    • 제26권1호
    • /
    • pp.1-11
    • /
    • 2019
  • Purpose: The goal was to use electronic health records to identify factors and outcomes associated with falls among patients admitted to hematology units. Methods: This retrospective case-control study included data from a tertiary university hospital. Analysis was done of records from 117 patients with a history of falls and 201 patients with no history of falls who were admitted to the hematology unit from January 1, 2013 to December 31, 2014. Risk factors were analyzed using hierarchical logistic regression; patient outcomes were analyzed using multiple logistic regression, Cox proportional hazards regression, and multiple linear regression. Results: Clinical factors such as self-care nursing (OR=4.47, CI=1.64~12.11), leukopenia (OR=6.03; CI=2.51~14.50), and hypoalbuminemia (OR=2.79, CI=1.31~5.96); treatment factors such as use of narcotics (OR=2.06, CI=1.01~4.19), antipsychotics (OR=3.05, CI=1.20~7.75), and steroids (OR=4.51, CI=1.92~10.58); and patient factors such as low education (OR=3.16, CI=1.44~6.94) were significant risk factors. Falls were also associated with increased length of hospital stay to 21.58 days (p<.001), and healthcare costs of 17,052,784 Won (p<.001). Conclusion: These findings can be a resource for fall prevention education and to help develop fall risk assessment tools for adults admitted to hematology units.

Ovarian Cancer Prognostic Prediction Model Using RNA Sequencing Data

  • Jeong, Seokho;Mok, Lydia;Kim, Se Ik;Ahn, TaeJin;Song, Yong-Sang;Park, Taesung
    • Genomics & Informatics
    • /
    • 제16권4호
    • /
    • pp.32.1-32.7
    • /
    • 2018
  • Ovarian cancer is one of the leading causes of cancer-related deaths in gynecological malignancies. Over 70% of ovarian cancer cases are high-grade serous ovarian cancers and have high death rates due to their resistance to chemotherapy. Despite advances in surgical and pharmaceutical therapies, overall survival rates are not good, and making an accurate prediction of the prognosis is not easy because of the highly heterogeneous nature of ovarian cancer. To improve the patient's prognosis through proper treatment, we present a prognostic prediction model by integrating high-dimensional RNA sequencing data with their clinical data through the following steps: gene filtration, pre-screening, gene marker selection, integrated study of selected gene markers and prediction model building. These steps of the prognostic prediction model can be applied to other types of cancer besides ovarian cancer.

Evaluating the effects of age on the long-term functional outcomes following anatomic total shoulder arthroplasty

  • Troy Li;Akiro H. Duey;Christopher A. White;Amit Pujari;Akshar V. Patel;Bashar Zaidat;Christine S. Williams;Alexis Williams;Carl M. Cirino;Dave Shukla;Bradford O. Parsons;Evan L. Flatow;Paul J. Cagle
    • Clinics in Shoulder and Elbow
    • /
    • 제26권3호
    • /
    • pp.231-237
    • /
    • 2023
  • Background: In the past decade, the number of anatomic total shoulder arthroplasty (aTSA) procedures has steadily increased. Patients over 65 years of age comprise the vast majority of recipients, and outcomes have been well documented; however, patients are opting for definitive surgical treatment at younger ages.We aim to report on the effects of age on the long-term clinical outcomes following aTSA. Methods: Among the patients who underwent TSA, 119 shoulders were retrospectively analyzed. Preoperative and postoperative clinical outcome data were collected. Linear regression analysis (univariate and multivariate) was conducted to evaluate the associations of clinical outcomes with age. Kaplan-Meier curves and Cox regression analyses were performed to evaluate implant survival. Results: At final follow-up, patients of all ages undergoing aTSA experienced significant and sustained improvements in all primary outcome measures compared with preoperative values. Based on multivariate analysis, age at the time of surgery was a significant predictor of postoperative outcomes. Excellent implant survival was observed over the course of this study, and Cox regression survival analysis indicated age and sex to not be associated with an increased risk of implant failure. Conclusions: When controlling for sex and follow-up duration, older age was associated with significantly better patient-reported outcome measures. Despite this difference, we noted no significant effects on range of motion or implant survival. Level of evidence: IV.

미국 위탁아동의 친권상실선고 이후 입양 결정요인에 관한 생존분석 (Timing and Risk Factors of Adoption for Legally-Free Foster Children after Having Parental Rights Terminated in the U. S.)

  • 송민경
    • 한국사회복지학
    • /
    • 제59권1호
    • /
    • pp.301-327
    • /
    • 2007
  • 본 연구의 목적은 미국에서 친권상실이 선고된 위탁아동의 입양률 추이를 살펴보고, 입양결정에 영향을 미치는 주된 요인을 규명하는 데 있다. 본 연구는 미국 위탁보호와 입양에 관한 패널데이터 FY1999-FY2002를 이용하여 1998년 10월부터 2002년 9월까지 32개 주를 추출하여 총 26,895명을 분석에 활용하였다. 사건사 분석의 Kaplan-Meier 분석과 비례적 위험회귀모형(Cox proportional hazards regression model)을 이용하여 친권상실선고 이후 소요되는 위탁기간에 따른 입양률 추이와 위험 입양배율(hazard ratios for adoption)를 산출하였다. 본 연구의 주요 결과로는 친권상실선고 이후 3개월-19개월까지 입양률이 급속히 증가하다가 20개월이 지나면서 오히려 감소추세를 보이고 있었다. 입양여부와 관련한 주요 요인으로서는 백인아동일 경우, 나이가 어릴수록, 선입양가족, 도시소재의 위탁보호일 경우, 양부모 위탁가족, 또는 인종적으로 동일한 위탁부모에 의해 위탁보호 될 경우 입양가능성이 상대적으로 높게 나타났다. 또한, 아동이 지체나 장애가 있을 경우, 신체학대나 성학대를 경험한 경우, 친부모의 양육능력부족으로 위탁보호 된 경우 상대적으로 낮은 입양가능성을 보이고 있다. 본 연구결과 친권상실 이전에 발생한 위탁보호 원인이 친권상실 이후에도 입양에 영향을 미치고 있으며, 입양촉진방안으로 친권상실선고 이후 제공된 위탁서비스 활용과 적극적 지원방안 모색의 필요성이 제기되었다. 끝으로 본 연구결과를 바탕으로 한국사회에서 요보호아동의 친권개입의 정책적 방향과 항구적 보호마련을 위한 함의와 제언을 개괄적으로 제시하였다.

  • PDF

Prognostic Value of 18F-FDG PET/CT Radiomics in Extranodal Nasal-Type NK/T Cell Lymphoma

  • Yu Luo;Zhun Huang;Zihan Gao;Bingbing Wang;Yanwei Zhang;Yan Bai;Qingxia Wu;Meiyun Wang
    • Korean Journal of Radiology
    • /
    • 제25권2호
    • /
    • pp.189-198
    • /
    • 2024
  • Objective: To investigate the prognostic utility of radiomics features extracted from 18F-fluorodeoxyglucose (FDG) PET/CT combined with clinical factors and metabolic parameters in predicting progression-free survival (PFS) and overall survival (OS) in individuals diagnosed with extranodal nasal-type NK/T cell lymphoma (ENKTCL). Materials and Methods: A total of 126 adults with ENKTCL who underwent 18F-FDG PET/CT examination before treatment were retrospectively included and randomly divided into training (n = 88) and validation cohorts (n = 38) at a ratio of 7:3. Least absolute shrinkage and selection operation Cox regression analysis was used to select the best radiomics features and calculate each patient's radiomics scores (RadPFS and RadOS). Kaplan-Meier curve and Log-rank test were used to compare survival between patient groups risk-stratified by the radiomics scores. Various models to predict PFS and OS were constructed, including clinical, metabolic, clinical + metabolic, and clinical + metabolic + radiomics models. The discriminative ability of each model was evaluated using Harrell's C index. The performance of each model in predicting PFS and OS for 1-, 3-, and 5-years was evaluated using the time-dependent receiver operating characteristic (ROC) curve. Results: Kaplan-Meier curve analysis demonstrated that the radiomics scores effectively identified high- and low-risk patients (all P < 0.05). Multivariable Cox analysis showed that the Ann Arbor stage, maximum standardized uptake value (SUVmax), and RadPFS were independent risk factors associated with PFS. Further, β2-microglobulin, Eastern Cooperative Oncology Group performance status score, SUVmax, and RadOS were independent risk factors for OS. The clinical + metabolic + radiomics model exhibited the greatest discriminative ability for both PFS (Harrell's C-index: 0.805 in the validation cohort) and OS (Harrell's C-index: 0.833 in the validation cohort). The time-dependent ROC analysis indicated that the clinical + metabolic + radiomics model had the best predictive performance. Conclusion: The PET/CT-based clinical + metabolic + radiomics model can enhance prognostication among patients with ENKTCL and may be a non-invasive and efficient risk stratification tool for clinical practice.

China's Brain Gain at the High End: An Assessment of Thousand Youth Talents Program

  • Sun, Yutao;Guo, Rongyu;Zhang, Shuai
    • Asian Journal of Innovation and Policy
    • /
    • 제6권3호
    • /
    • pp.274-294
    • /
    • 2017
  • While studies have viewed the effect of Chinese talent-attracting programs launched by government since reform and open door policy, little of them has assessed these programs empirically and pertinently. This article intends to assess an important program - the Thousand Youth Talents Program (TYTP). Frist, this paper proposed a transnational migration matrix of the academics to clarify the dynamic mechanism of academic brain gain at the high end. Then, the Kaplan-Meier analysis and Cox regression model are used to empirically analyze the policy effect of TYTP. The results show that, academic ability have double edged impacts on brain gain at the high end, some scholars whose last employer's academic ranking is world's Top100 have stronger willing to return, and the negative effect of academic ranking decreases with time passing; while scholars with a tenure-track position, a tenure position or a permanent position tend to stay overseas, and the hazard rate of staying increases with age. The older scholars have more intentions to go back China, while gender was not a significant factor influencing academic return at the high end. That is, the talent-attracting programs has partly succeeded in bringing back the academics at the high end.

Prognostic Factors for Survival of Patients with Extensive Stage Small Cell Lung Cancer - a Retrospective Single Institution Analysis

  • Wu, Chao;Li, Fang;Jiao, Shun-Chang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권10호
    • /
    • pp.4959-4962
    • /
    • 2012
  • The objective of this retrospective study was to investigate prognostic factors associated with survival of patients with extensive stage small cell lung cancer (ES-SCLC). Included were 200 patients admitted to the Liberation Army General Hospital with a diagnosis of ES-SCLC. The demographics of patients, disease characteristics, pre-treatment biochemical parameters and therapeutic plan were assessed or evaluated. Univariate analysis found that second-line chemotherapy, radiotherapy, and no liver metastasis were associated with improved survival. Tumor response to first-line chemotherapy and normal initial hemoglobin levels were also associated with a survival benefit (all P-values ${\leq}$ 0.0369). Multivariate Cox regression analysis indicated that liver metastasis and the total number of all chemotherapy cycles were independent prognostic factors of survival. The morbidity risk in patients with liver metastasis was 2.52-fold higher than that in patients without liver metastasis (hazard ratio (HR)=2.52 (1.69-3.76); P<0.0001). However, one unit increase in the total number of chemotherapy cycles decreased the risk of death by 0.86-fold (HR=0.86 (0.80-0.92); P<0.0001). Absence of liver metastasis and ability of a patient to receive and tolerate multiple lines of chemotherapy were associated with longer survival.