• 제목/요약/키워드: predictive accuracy

검색결과 782건 처리시간 0.093초

Role of a Risk of Malignancy Index in Clinical Approaches to Adnexal Masses

  • Simsek, Hakki Sencer;Tokmak, Aytekin;Ozgu, Emre;Doganay, Melike;Danisman, Nuri;Erkaya, Salim;Gungor, Tayfun
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권18호
    • /
    • pp.7793-7797
    • /
    • 2014
  • Objective: The aim of this study was to evaluate predictive role of risk of malignancy index in discriminating between benign and malignant adnexal masses preoperatively. Methods: This retrospective study was conducted with a total of 569 patients with adnexal masses/ovarian cysts managed surgically at our clinic between January 2006 and January 2012. Obtained data from patient files were age, gravidity, parity, menopause status, ultrasound findings and CA125 levels. For all patients ultrasound scans were performed. For the assessment of risk of malignancy index (RMI) Jacobs' model was used. Histopathologic results of all patients were recorded postoperatively. Malignancy status of the surgically removed adnexal mass was the gold standard. Results: Of the total masses, 245 (43.1%) were malignant, 316 (55.5%) were benign and 8 (1.4%) were borderline. The mean age of benign cases was lower than malign cases ($35.2{\pm}10.9$ versus $50.8{\pm}13.4$, p<0.001). Four hundred and five of them (71.2%) were in premenopausal period. Malignant tumors were more frequent in postmenopausal women (81% versus 29%, p<0.001). All ultrasound parameters of RMI were statistically significantly favorable for malignant masses. In our study ROC curve analysis for RMI provided maximum Youden index at level of 163.85. When we based on cutoff level for RMI as 163.85 sensitivity, specificity, PPV, NPV was calculated 74.7%, 96.2%, 94% and 82.6%, respectively. Conclusions: RMI was found to be a significant marker in preoperative evaluation and management of patients with an adnexal mass, and was useful for referring patients to tertiary care centers. Although utilization of RMI provides increased diagnostic accuracy in preoperative evaluation of patient with an adnexal mass, new diagnostic tools with higher sensitivity and specificity are needed to discriminate ovarian cancer from benign masses.

Comparison of α1-Antitrypsin, α1-Acid Glycoprotein, Fibrinogen and NOx as Indicator of Subclinical Mastitis in Riverine Buffalo (Bubalus bubalis)

  • Guha, Anirban;Guha, Ruby;Gera, Sandeep
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제26권6호
    • /
    • pp.788-794
    • /
    • 2013
  • Mastitis set apart as clinical and sub clinical is a disease complex of dairy cattle, with sub clinical being the most important economically. Of late, laboratories showed interest in developing biochemical markers to diagnose sub clinical mastitis (SCM) in herds. Many workers reported noteworthy alternation of acute phase proteins (APPs) and nitric oxide, (measured as nitrate+nitrite = NOx) in milk due to intra-mammary inflammation. But, the literature on validation of these parameters as indicators of SCM, particularly in riverine milch buffalo (Bubalus bubalis) milk is inadequate. Hence, the present study focused on comparing several APPs viz. ${\alpha}_1$-anti trypsin, ${\alpha}_1$-acid glycoprotein, fibrinogen and NOx as indicators of SCM in buffalo milk. These components in milk were estimated using standardized analytical protocols. Somatic cell count (SCC) was done microscopically. Microbial culture was done on 5% ovine blood agar. Of the 776 buffaloes (3,096 quarters) sampled, only 347 buffaloes comprising 496 quarters were found positive for SCM i.e. milk culture showed growth in blood agar with $SCC{\geq}2{\times}10^5$ cells/ml of milk. The cultural examination revealed Gram positive bacteria as the most prevalent etiological agent. It was observed that ${\alpha}_1$-anti trypsin and NOx had a highly significant (p<0.01) increase in SCM milk, whereas, the increase of ${\alpha}_1$-acid glycoprotein in infected milk was significant (p<0.05). Fibrinogen was below detection level in both healthy and SCM milk. The percent sensitivity, specificity and accuracy, predictive values and likelihood ratios were calculated taking bacterial culture examination and $SCC{\geq}2{\times}10^5$ cells/ml of milk as the benchmark. Udder profile correlation coefficient was also used. Allowing for statistical and epidemiological analysis, it was concluded that ${\alpha}_1$-anti trypsin indicates SCM irrespective of etiology, whereas ${\alpha}_1$-acid glycoprotein better diagnosed SCM caused by gram positive bacteria. NOx did not prove to be a good indicator of SCM. It is recommended measuring both ${\alpha}_1$-anti trypsin and ${\alpha}_1$-acid glycoprotein in milk to diagnose SCM in buffalo irrespective of etiology.

Differentiation of Benign from Malignant Adnexal Masses by Functional 3 Tesla MRI Techniques: Diffusion-Weighted Imaging and Time-Intensity Curves of Dynamic Contrast-Enhanced MRI

  • Malek, Mahrooz;Pourashraf, Maryam;Mousavi, Azam Sadat;Rahmani, Maryam;Ahmadinejad, Nasrin;Alipour, Azam;Hashemi, Firoozeh Sadat;Shakiba, Madjid
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권8호
    • /
    • pp.3407-3412
    • /
    • 2015
  • Background: The aim of this study was to evaluate and compare the accuracy of diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) value, and time-intensity curve (TIC) type analysis derived from dynamic contrast-enhanced MR imaging (DCE-MRI) in differentiating benign from malignant adnexal masses. Materials and Methods: 47 patients with 56 adnexal masses (27 malignant and 29 benign) underwent DWI and DCE-MRI examinations, prior to surgery. DWI signal intensity, mean ADC value, and TIC type were determined for all the masses. Results: High signal intensity on DWI and type 3 TIC were helpful in differentiating benign from malignant adnexal masses (p<0.001). The mean ADC value was significantly lower in malignant adnexal masses (p<0.001). An ADC value< $1.20{\times}10^{-3}mm^2/s$ may be the optimal cutoff for differentiating between benign and malignant tumors. The negative predictive value for low signal intensity on DWI, and type 1 TIC were 100%. The pairwise comparison among the receiver operating characteristic (ROC) curves showed that the area under the curve (AUC) of TIC was significantly larger than the AUCs of DWI and ADC (p<0.001 for comparison of TIC and DWI, p<0.02 for comparison of TIC and ADC value). Conclusions: DWI, ADC value and TIC type derived from DCE-MRI are all sensitive and relatively specific methods for differentiating benign from malignant adnexal masses. By comparing these functional MR techniques, TIC was found to be more accurate than DWI and ADC.

Relationships between EGFR Mutation Status of Lung Cancer and Preoperative Factors - Are they Predictive?

  • Usuda, Katsuo;Sagawa, Motoyasu;Motono, Nozomu;Ueno, Masakatsu;Tanaka, Makoto;Machida, Yuichiro;Matoba, Munetaka;Taniguchi, Mitsuru;Tonami, Hisao;Ueda, Yoshimichi;Sakuma, Tsutomu
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권2호
    • /
    • pp.657-662
    • /
    • 2014
  • Background: The epidermal growth factor receptor (EGFR) mutation status of lung cancer is important because it means that EGFR-tyrosine kinase inhibitor treatment is indicated. The purpose of this prospective study is to determine whether EGFR mutation status could be identified with reference to preoperative factors. Materials and Methods: One hundred-forty eight patients with lung cancer (111 adenocarcinomas, 25 squamous cell carcinomas and 12 other cell types) were enrolled in this study. The EGFR mutation status of each lung cancer was analyzed postoperatively. Results: There were 58 patients with mutant EGFR lung cancers (mutant LC) and 90 patients with wild-type EGFR lung cancers (wild-type LC). There were significant differences in gender, smoking status, maximum tumor diameter in chest CT, type of tumor shadow, clinical stage between mutant LC and wild-type LC. EGFR mutations were detected only in adenocarcinomas. Maximum standardized uptake value (SUVmax:$3.66{\pm}4.53$) in positron emission tomography-computed tomography of mutant LC was significantly lower than that ($8.26{\pm}6.11$) of wild-type LC (p<0.0001). Concerning type of tumor shadow, the percentage of mutant LC was 85.7% (6/7) in lung cancers with pure ground glass opacity (GGO), 65.3%(32/49) in lung cancers with mixed GGO and 21.7%(20/92) in lung cancers with solid shadow (p<0.0001). For the results of discriminant analysis, type of tumor shadow (p=0.00036) was most significantly associated with mutant EGFR. Tumor histology (p=0.0028), smoking status (p=0.0051) and maximum diameter of tumor shadow in chest CT (p=0.047) were also significantly associated with mutant EGFR. The accuracy for evaluating EGFR mutation status by discriminant analysis was 77.0% (114/148). Conclusions: Mutant EGFR is significantly associated with lung cancer with pure or mixed GGO, adenocarcinoma, never-smoker, smaller tumor diameter in chest CT. Preoperatively, EGFR mutation status can be identified correctly in about 77 % of lung cancers.

대사증후군의 인지와 신체활동 실천에 영향을 미치는 요인: 데이터 마이닝 접근 (Factors influencing metabolic syndrome perception and exercising behaviors in Korean adults: Data mining approach)

  • 이수경;문미경
    • 한국산학기술학회논문지
    • /
    • 제18권12호
    • /
    • pp.581-588
    • /
    • 2017
  • 본 연구는 기계 학습법 중 하나인 XGBoost를 이용하여 대사증후군을 인지하고 신체활동을 수행하는 집단을 예측하고자 2014년 7월부터 2015년 12월까지 시도되었다. 이에 2009-2013년 지역사회건강조사를 연구자료로 사용하였고 370,430명의 성인을 분석에 포함하였다. 본 연구의 종속변수는 대사증후군의 인지 및 신체활동 실천정도에 따른 단계로 3단계로 구분하였다:Stage 1(무인지, 무 신체활동), Stage 2(인지, 무 신체활동), and Stage 3(인지, 신체활동). 예측변수로는 5년간의 지역사회건강조사 중 공통으로 수집된 문항으로부터 161개의 특성을 선택하였다. 자료 분석을 위해 R program을 이용하여 XGBoost 알고리즘을 적용하였다. 분석 결과 정확도는 0.735 이었으며, 가장 영향을 미치는 10개의 특성은 나이, 교육수준, 체중조절시도 경험, EQ-5D 운동능력, 영양표시 확인, 개인 건강보험가입 유무, EQ-5D 일상활동, 금연광고경험 여부, 통증유무, 당뇨에 대한 보건기관의 교육 경험 순으로 확인되었다. 본 연구결과는 XGBoost가 보건의료빅데이터를 이용한 질병의 예방과 관리에 영향을 주는 요인을 확인하는데 유용한 도구임을 보여주었다. 또한, 본 연구를 통해 대사증후군에 취약한 계층을 확인하고 이를 위한 교육프로그램 개발에 도움을 줄 수 있을 것으로 보인다.

Development of Predictive Mathematical Model for the Growth Kinetics of Staphylococcus aureus by Response Surface Model

  • Seo, Kyo-Young;Heo, Sun-Kyung;Lee, Chan;Chung, Duck-Hwa;Kim, Min-Gon;Lee, Kyu-Ho;Kim, Keun-Sung;Bahk, Gyung-Jin;Bae, Dong-Ho;Kim, Kwang-Yup;Kim, Cheorl-Ho;Ha, Sang-Do
    • Journal of Microbiology and Biotechnology
    • /
    • 제17권9호
    • /
    • pp.1437-1444
    • /
    • 2007
  • A response surface model was developed for predicting the growth rates of Staphylococcus aureus in tryptic soy broth (TSB) medium as a function of combined effects of temperature, pH, and NaCl. The TSB containing six different concentrations of NaCl (0, 2, 4, 6, 8, and 10%) was adjusted to an initial of six different pH levels (pH 4, 5, 6, 7, 8, 9, and 10) and incubated at 10, 20, 30, and $40^{\circ}C$. In all experimental variables, the primary growth curves were well ($r^2=0.9000$ to 0.9975) fitted to a Gompertz equation to obtain growth rates. The secondary response surface model for natural logarithm transformations of growth rates as a function of combined effects of temperature, pH, and NaCl was obtained by SAS's general linear analysis. The predicted growth rates of the S. aureus were generally decreased by basic (pH 9-10) or acidic (pH 5-6) conditions and higher NaCl concentrations. The response surface model was identified as an appropriate secondary model for growth rates on the basis of correlation coefficient (r=0.9703), determination coefficient ($r^2=0.9415$), mean square error (MSE=0.0185), bias factor ($B_f=1.0216$), and accuracy factor ($A_f=1.2583$). Therefore, the developed secondary model proved reliable for predictions of the combined effect of temperature, NaCl, and pH on growth rates for S. aureus in TSB medium.

Development of Kinetic Models Describing Kinetic Behavior of Bacillus cereus and Staphylococcus aureus in Milk

  • Kim, Hyoun Wook;Lee, Sun-Ah;Yoon, Yohan;Paik, Hyun-Dong;Ham, Jun-Sang;Han, Sang-Ha;Seo, Kuk-Hwan;Jang, Aera;Park, Bum-Young;Oh, Mi-Hwa
    • 한국축산식품학회지
    • /
    • 제33권2호
    • /
    • pp.155-161
    • /
    • 2013
  • This study developed predictive models to evaluate the kinetic behaviors of Bacillus cereus and Staphylococcus aureus in milk during storage at various temperatures. B. cereus and S. aureus (3 Log CFU/mL) were inoculated into milk and stored at $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, as well as $5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$, respectively, while bacterial populations were enumerated. The growth data were fitted to the modified Gompertz model to estimate kinetic parameters, including the maximum specific growth rate (${\mu}_{max}$; Log CFU/[$mL{\cdot}h$]), lag phase duration (LPD; h), lower asymptote ($N_0$; Log CFU/mL), and upper asymptote ($N_{max}$; Log CFU/mL). To describe the kinetic behavior of B. cereus and S. aureus, the parameters were fitted to the square root model as a function of storage temperature. Finally, the developed models were validated with the observed data, and Bias (B) and Accuracy (A) factors were calculated. Cell counts of both bacteria increased with storage time. Primary modeling yielded the following parameters; ${\mu}_{max}$: 0.14-0.75 and 0.06-0.51 Log CFU/mL/h; LPD: 1.78-14.03 and 0.00-1.44 h, $N_0$: 3.10-3.37 and 2.09-3.07 Log CFU/mL, and $N_{max}$: 7.59-8.87 and 8.60-9.32 Log CFU/mL for B. cereus and S. aureus, respectively. Secondary modeling yielded a determination of coefficient ($R^2$) of 0.926.0.996. B factors were 1.20 and 0.94, and A factors were 1.16 and 1.08 for B. cereus and S. aureus, respectively. Thus, the mathematical models developed here should be useful in describing the kinetic behaviors of B. cereus and S. aureus in milk during storage.

안개 발생에 따른 문화재 표면의 색 변화 예측 연구 (Study on the Prediction of Surface Color Change of Cultural Properties Materials by Fog Occurrence)

  • 한예빈;박상현;유지아;정용재
    • 보존과학회지
    • /
    • 제32권4호
    • /
    • pp.491-500
    • /
    • 2016
  • 안개는 매우 작은 물방울이 대기 중에 떠다니는 현상으로 주변의 온도, 습도, 바람, 지형 등에 따라 안개의 형태나 발생 여부 등이 달라진다. 특히 안개는 수분을 함유하는 수원(水源) 근처에서 온습도 차이로 인해 발생하기 쉬우며, 오늘날 기후 변화는 안개 발생에 더욱 영향을 미칠 수 있다. 본 연구에서는 다양한 기후요인 중 안개가 문화재에 미치는 영향을 알아보고자 각 재질에 대해 옥외폭로 및 인공열화를 실시하였으며 지속적인 안개 발생으로 인한 재질의 손상정도를 예측하기 위해 색변화를 중심으로 회귀분석을 실시하였다. 금속 표준시편에 대한 옥외폭로 및 인공열화 결과, 표면 변화가 크게 발생하였으며 화견 및 단청류의 경우 표면상 열화된 모습은 관찰되었으나 색차의 경우 일정한 경향성은 확인되지 않았다. 안개 발생빈도에 따라 유의적인 색변화가 발생한 금속 표준시편을 대상으로 안개 발생빈도에 따른 색 변화 예측식을 작성하였으며, 실제 옥외폭로를 통한 색차값의 비교를 통해 색 변화 예측식의 적용 가능성을 확인하였다. 이를 바탕으로 향후 보다 종합적인 손상 예측식을 수립한다면 실제 현장에서 보존환경에 따른 재질의 손상도 예측이 가능할 것으로 기대된다.

의사결정나무분석을 이용한 청소년 우울의 보호요인 예측모형 (Predictors of Protective Factors for Depression in Adolescent using Decision Making Tree Analysis)

  • 김보영
    • 한국콘텐츠학회논문지
    • /
    • 제15권5호
    • /
    • pp.375-385
    • /
    • 2015
  • 본 연구는 의사결정나무 분석을 활용하여 청소년의 우울 보호요인을 예측하여 우울 예방과 조기발견 및 중재 방안을 마련하고자 시도된 서술적 조사연구이다. 연구대상은 G광역시에 소재한 청소년 총 485명이고, 자료 수집은 2013년 9월 23일부터 9월 26일 사이에 이루어졌다. 자료 분석은 SPSS 20.0 프로그램을 이용하여 빈도, 백분율, 평균과 표준편차 및 ${\chi}^2$-test, t-test, 의사결정나무 분석으로 분석하였다. 본 연구 결과, 4개의 경로, 총 12노드가 구축되었고 가족 결속력, 부모 자녀간 의사소통과 또래와의 의사소통이 청소년 우울 보호요인이었다. 우울의 보호요인 예측 정확도에서 분석용은 특이도 76.0%, 민감도 65.4%이었고, 검정용은 특이도 78.2%, 민감도 63.7%이었으며, 전체 분류 정확도는 분석용 70.1%, 검정용 69.7%이었다. 이에 본 연구 결과가 학교와 지역사회에서 청소년 정신보건을 담당하는 전문가들에게 우울을 예방을 위한 프로그램 개발의 기초자료로 제공되고, 나아가 청소년들이 자신들의 목소리를 되찾고 힘차게 성장하기 위한 보호요인 강화를 위한 우울예방 정책 전략에 활용되기를 기대해 본다.

내부통제 취약기업 예측과 특성에 관한 연구 - 상장기업군과 비상장기업군 중심으로 - (A Study about Internal Control Deficient Company Forecasting and Characteristics - Based on listed and unlisted companies -)

  • 유길현;김대룡
    • 디지털융복합연구
    • /
    • 제15권2호
    • /
    • pp.121-133
    • /
    • 2017
  • 본 연구는 취약한 내부통제시스템을 형성하고 있을 가능성이 높은 기업들을 예측하는 적합한 모형을 형성하고, 이를 기반으로 취약기업의 특성을 살펴보고자 했다. 분석에 사용된 자료는 K_금융기관과 대출거래가 이루어졌던 상장법인과 비상장법인을 대상으로 하였다. 주요 결과로, 금융기관이 내부통제가 취약한 기업을 예측하기 위해서는 로짓모형에 비해 판별모형이 적합하다는 결론에 도달했다. 판별모형이 내부통제 취약기업을 취약기업으로 예측하는 정확도가 높고, 취약기업을 정상기업으로 잘못분류 할 오류가 낮았기 때문이다. 내부통제가 취약한 기업의 주요특성은 낮은 신용도, 낮은 자산건전성, 높은 연체율, 낮은 영업활동현금흐름, 높은 부채비율, 그리고 부(-)의 매출액영업이익률을 형성하는 기업으로 나타났다. 본 내부통제 취약예측모형을 포함한 연구결과는 자료구성의 한계로 연구가 이루어지지 않았던 비상장기업군까지 확장하였기에, 금융기관이 내부통제 취약가능성이 높은 기업을 사전적으로 예측하여 자산손실을 예방하는 도구로 이용할 수 있을 것이다.