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find Keyword "logistic regression" 19 results
  • Analysis of Influential Factors on Shortterm Outcome after Total Correction of Tetralogy of Fallot

    Abstract: Objective To investigate the method of improving effect, by investigating and analyzing the possible risk factors affecting shortterm outcome after total correction of tetralogy of Fallot (TOF). Methods Data of 219 patients who received total correction of TOF were divided into two groups according to the length of postoperative stay in hospital and recovery of heart function in the near future. Group A(n=110): patients had good recovery of heart function classified as gradeⅠorⅡ(NYHA classification), and could smoothly be discharged from the hospital within two weeks without serious complications. The left ventricular ejection fraction (LVEF) had to exceed to 0.50 during 6 months followup visit. Group B(n=109): patients had worse recovery of heart function classified as grade Ⅱ or Ⅲ, and could not be discharged within two weeks with severe complications. LVEF was less than 0.50 during 6 months followup visit. The clinical data of two groups were compared, and risk factors affecting shortterm outcome after total correction of TOF operation were analyzed by logistic regression and model selection. Results There were good recovery of heart function classified as gradeⅠorⅡ(NYHA classification)in discharge, no death, and LVEF all exceeded to 0.50 in group A; there were 8 deaths in group B (7.34 %), and recovery of heart function was worse classified as grade Ⅱ or Ⅲ, with LVEF being less than 0.50(Plt;0.01). Amount of postoperative daily thoracic drainage, assisted respiration time, time of inotropic agent stabilizing circulation, and the average length of postoperative stay in group A were all less or short than those in group B(Plt;0.01). But the bypass and clamping time of group B were exceeded group A. The ratio of patching astride annulus in group B was greater than that in group A, and Nakata index was less than that in group A(Plt;0.01). The results of logistic regression and model selection indicate: age at repair (OR=0.69), oxygen saturation(OR=0.98), haematocrit before operation (OR=0.94), and patching astride annulus (OR=46.86), Nakata index (OR=16.90), amount of postoperative daily thoracic drainage (OR=0.84), presence of arrhythmia(OR=0.87), and wound infection(OR=63.57) have significant effect with shortterm outcome after total correction of TOF operation. Conclusions The probable methods to improving effect of shortterm outcome after total correction of TOF are an earlier age at repair, decreasing haematocrit, rising oxygen saturation before surgery, performing a palliative operation facilitating development of arteriae pulmonalis in earlier time, improving the surgical technique, and strengthening the perioperative care. 

    Release date:2016-08-30 06:16 Export PDF Favorites Scan
  • Selection and Classification of Elastic Net Feature with Fused Electroencephalogram Features

    Signal classification is a key of brain-computer interface (BCI). In this paper, we present a new method for classifying the electroencephalogram (EEG) signals of which the features are heterogeneous. This method is called wrapped elastic net feature selection and classification. Firstly, we used the joint application of time-domain statistic, power spectral density (PSD), common spatial pattern (CSP) and autoregressive (AR) model to extract high-dimensional fused features of the preprocessed EEG signals. Then we used the wrapped method for feature selection. We fitted the logistic regression model penalized with elastic net on the training data, and obtained the parameter estimation by coordinate descent method. Then we selected best feature subset by using 10-fold cross-validation. Finally, we classified the test sample using the trained model. Data used in the experiment were the EEG data from international BCI Competition Ⅳ. The results showed that the method proposed was suitable for fused feature selection with high-dimension. For identifying EEG signals, it is more effective and faster, and can single out a more relevant subset to obtain a relatively simple model. The average test accuracy reached 81.78%.

    Release date:2017-01-17 06:17 Export PDF Favorites Scan
  • Construction and verification of preoperative malignant risk diagnostic model for ovarian tumors

    Objective To construct and verify the diagnostic model of preoperative malignant risk of ovarian tumors, so as to improve the diagnostic efficiency of existing test indexes. Methods The related serological indicators and clinical data of patients with ovarian tumors confirmed by pathology who were treated in the Affiliated Hospital of Southwest Medical University between January 2019 and September 2023 were retrospectively collected, and the patients were randomly divided into a training set and a verification set at a 7∶3 ratio. Logistic regression was used to construct a diagnostic model in the training set, and the diagnostic efficacy of the model was verified through discrimination, calibration, clinical benefit, and clinical applicability evaluation. Results A total of 929 patients with ovarian tumors were included, including 318 cases of malignant ovarian tumors and 611 cases of benign ovarian tumors. The patients were randomly divided into a training set of 658 cases and a validation set of 271 cases. A diagnostic model was constructed using logistic regression in the training set, containing 5 factors namely age, percentage of neutrophil (NEU%), fibrinogen to albumin ratio (FAR), carbohydrate antigen 125 (CA125), and human epididymis protein 4 (HE4): modelUAM=−3.211+0.667×age+2.966×CA125+0.792×FAR+1.637×HE4+0.533×NEU%, with a Hosmer-Lemeshow test P-value of 0.21. The area under the receiver operating characteristic (ROC) curve measured in the training set was 0.927 [95% confidence interval (0.903, 0.951)], the sensitivity was 0.947, and the specificity was 0.780. The area under the ROC curve of the validation set was 0.888 [95% confidence interval (0.840, 0.930)], the sensitivity was 0.744, and the specificity was 0.901. Conclusion A new quantitative tool based on age, NEU%, FAR, CA125 and HE4 can be used for the clinical diagnosis of ovarian malignant tumors, and it is helpful to improve the diagnostic efficiency and is worth popularizing.

    Release date:2024-10-25 01:48 Export PDF Favorites Scan
  • Risk factors for postoperative respiratory failure in patients with esophageal cancer and the prediction model establishment

    ObjectiveTo explore the risk factors for postoperative respiratory failure (RF) in patients with esophageal cancer, construct a predictive model based on the least absolute shrinkage and selection operator (LASSO)-logistic regression, and visualize the constructed model. MethodsA retrospective analysis was conducted on patients with esophageal cancer who underwent surgical treatment in the Department of Thoracic Surgery, Sun Yat-sen University Cancer Center Gansu Hospital from 2020 to 2023. Patients were divided into a RF group and a non-RF (NRF) group according to whether RF occurred after surgery. Clinical data of the two groups were collected, and LASSO-logistic regression was used to optimize feature selection and construct the predictive model. The model was internally validated by repeated sampling 1000 times based on the Bootstrap method. ResultsA total of 217 patients were included, among which 24 were in the RF group, including 22 males and 2 females, with an average age of (63.33±9.10) years; 193 were in the NRF group, including 161 males and 32 females, with an average age of (62.14±8.44) years. LASSO-logistic regression analysis showed that the percentage of forced expiratory volume in one second/forced vital capacity (FEV1/FVC) to predicted value (FEV1/FVC%pred) [OR=0.944, 95%CI (0.897, 0.993), P=0.026], postoperative anastomotic fistula [OR=4.106, 95%CI (1.457, 11.575), P=0.008], and postoperative lung infection [OR=3.776, 95%CI (1.373, 10.388), P=0.010] were risk factors for postoperative RF in patients with esophageal cancer. Based on the above risk factors, a predictive model was constructed, with an area under the receiver operating characteristic curve of 0.819 [95%CI (0.737, 0.901)]. The Hosmer-Lemeshow test for the calibration curve showed that the model had good goodness of fit (P=0.527). The decision curve showed that the model had good clinical net benefit when the threshold probability was between 5% and 50%. Conclusion FEV1/FVC%pred, postoperative anastomotic fistula, and postoperative lung infection are risk factors for postoperative RF in patients with esophageal cancer. The predictive model constructed based on LASSO-logistic regression analysis is expected to help medical staff screen high-risk patients for early individualized intervention.

    Release date:2025-02-28 06:45 Export PDF Favorites Scan
  • A New Method for Diagnosing Erythemato-squamous Diseases Based on Virtual Coding and Multinomial Logistic Regression Penalized via Elastic Net

    Erythemato-squamous diseases are a general designation of six common skin diseases, of which the differential diagnosis is a difficult problem in dermatology. This paper presents a new method based on virtual coding for qualitative variables and multinomial logistic regression penalized via elastic net. Considering the attributes of variables, a virtual coding is applied and contributes to avoid the irrationality of calculating nominal values directly. Multinomial logistic regression model penalized via elastic net is thence used to fit the correlation between the features and classification of diseases. At last, parameter estimations can be attained through coordinate descent. This method reached accuracy rate of 98.34%±0.0027% using 10-fold cross validation in the experiments. Our method attained equivalent accuracy rate compared to the results of other methods, but steps are simpler and stability is higher.

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  • A postoperative in-hospital mortality risk model for elderly patients undergoing cardiac valvular surgery based on LASSO-logistic regression

    Objective To evaluate the risk factors for postoperative in-hospital mortality in elderly patients receiving cardiac valvular surgery, and develop a new prediction models using the least absolute shrinkage and selection operator (LASSO)-logistic regression. Methods The patients≥65 years who underwent cardiac valvular surgery from 2016 to 2018 were collected from the Chinese Cardiac Surgery Registry (CCSR). The patients who received the surgery from January 2016 to June 2018 were allocated to a training set, and the patients who received the surgery from July to December 2018 were allocated to a testing set. The risk factors for postoperative mortality were analyzed and a LASSO-logistic regression prediction model was developed and compared with the EuroSCOREⅡ. Results A total of 7 163 patients were collected in this study, including 3 939 males and 3 224 females, with a mean age of 69.8±4.5 years. There were 5 774 patients in the training set and 1389 patients in the testing set. Overall, the in-hospital mortality was 4.0% (290/7163). The final LASSO-logistic regression model included 7 risk factors: age, preoperative left ventricular ejection fraction, combined coronary artery bypass grafting, creatinine clearance rate, cardiopulmonary bypass time, New York Heart Association cardiac classification. LASSO-logistic regression had a satisfying discrimination and calibration in both training [area under the curve (AUC)=0.785, 0.627] and testing cohorts (AUC=0.739, 0.642), which was superior to EuroSCOREⅡ. Conclusion The mortality rate for elderly patients undergoing cardiac valvular surgery is relatively high. LASSO-logistic regression model can predict the risk of in-hospital mortality in elderly patients receiving cardiac valvular surgery.

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  • EFFECT FACTORS ANALYSIS OF KNEE FUNCTION RECOVERY AFTER DISTAL FEMORAL FRACTURE OPERATION

    Objective To investigate the effect factors of knee function recovery after operation in distal femoral fractures. Methods From January 2001 to May 2007, 92 cases of distal femoral fracture were treated. There were 50 males and 42 females, aged 20-77 years old (average 46.7 years old). Fracture was caused by traffic accident in 48 cases, by fall ing fromheight in 26 cases, by bruise in 12 cases and by tumble in 6 cases. According to Müller’s Fracture classification, there were 29 cases of type A, 12 cases of type B and 51 cases of type C. According to American Society of Anesthesiologists (ASA) classification, there were 21 cases of grade I, 39 cases of grade II, 24 cases of grade III, and 8 cases of grade IV. The time from injury to operation was 4 hours to 24 days with an average of 7 days. Anatomical plate was used in 43 cases, retrograde interlocking intramedullary nail in 37 cases, and bone screws, bolts and internal fixation with Kirschner pins in 12 cases. After operation, the HSS knee function score was used to evaluate efficacy. Ten related factors were appl ied for statistical analysis, to knee function recovery after operation in distal femoral fractures, such as age, sex, preoperative ASA classification, injury to surgery time, fracture type, treatment, reduction qual ity, functional exercise after operation, whether or not CPM functional training and postoperative compl ications. Results Wound healed by first intention in 88 cases, infection occurred in 4 cases. All patients followed up 16-32 months with an average of 23.1 months. Cl inical union of fracture was achieved within 3-7 months after operation. Extensor device adhesions and the scope of activities of lt; 80° occurred in 29 cases, traumatic arthritis in 25 cases, postoperative fracture displacement in 6 cases, mild knee varus or valgus in 7 cases and implant loosening in 6 cases. According to HSS knee function score, the results were excellent in 52 cases, good in 15 cases, fair in 10 cases and poor in 15 cases with an excellent andgood rate of 72.83%. Single factor analysis showed that age, preoperative ASA classification, fracture type, reduction qual ity, whether or not CPM functional exercise, and postoperative compl ications were significantly in knee function recovery (P lt; 0.05). logistic regression analysis showed that the fracture type, qual ity of reduction, whether or not CPM functional exercise, and age were major factors in the knee joint function recovery. Conclusion Age, preoperative ASA classification, fracture type, reduction qual ity, and whether or not CPM functional training, postoperative compl ications factors may affect the knee joint function recovery. Adjustment to the patient’s preoperative physical status, fractures anatomic reduction and firm fixation, early postoperative active and passive functional exercises, less postoperative compl ications can maximize the restoration of knee joint function.

    Release date:2016-09-01 09:08 Export PDF Favorites Scan
  • Risk factor analysis and prediction model construction for hospital infections in tertiary hospitals in Gansu Province

    Objective To explore the independent risk factors for hospital infections in tertiary hospitals in Gansu Province, and establish and validate a prediction model. Methods A total of 690 patients hospitalized with hospital infections in Gansu Provincial Hospital between January and December 2021 were selected as the infection group; matched with admission department and age at a 1∶1 ratio, 690 patients who were hospitalized during the same period without hospital infections were selected as the control group. The information including underlying diseases, endoscopic operations, blood transfusion and immunosuppressant use of the two groups were compared, the factors influencing hospital infections in hospitalized patients were analyzed through multiple logistic regression, and the logistic prediction model was established. Eighty percent of the data from Gansu Provincial Hospital were used as the training set of the model, and the remaining 20% were used as the test set for internal validation. Case data from other three hospitals in Gansu Province were used for external validation. Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) were used to evaluate the model effectiveness. Results Multiple logistic regression analysis showed that endoscopic therapeutic manipulation [odds ratio (OR)=3.360, 95% confidence interval (CI) (2.496, 4.523)], indwelling catheter [OR=3.100, 95%CI (2.352, 4.085)], organ transplantation/artifact implantation [OR=3.133, 95%CI (1.780, 5.516)], blood or blood product transfusions [OR=3.412, 95%CI (2.626, 4.434)], glucocorticoids [OR=2.253, 95%CI (1.608, 3.157)], the number of underlying diseases [OR=1.197, 95%CI (1.068, 1.342)], and the number of surgical procedures performed during hospitalization [OR=1.221, 95%CI (1.096, 1.361)] were risk factors for hospital infections. The regression equation of the prediction model was: logit(P)=–2.208+1.212×endoscopic therapeutic operations+1.131×indwelling urinary catheters+1.142×organ transplantation/artifact implantation+1.227×transfusion of blood or blood products+0.812×glucocorticosteroids+0.180×number of underlying diseases+0.200×number of surgical procedures performed during the hospitalization. The internal validation set model had a sensitivity of 72.857%, a specificity of 77.206%, an accuracy of 76.692%, and an AUC value of 0.817. The external validation model had a sensitivity of 63.705%, a specificity of 70.934%, an accuracy of 68.669%, and an AUC value of 0.726. Conclusions Endoscopic treatment operation, indwelling catheter, organ transplantation/artifact implantation, blood or blood product transfusion, glucocorticoid, number of underlying diseases, and number of surgical cases during hospitalization are influencing factors of hospital infections. The model can effectively predict the occurrence of hospital infections and guide the clinic to take preventive measures to reduce the occurrence of hospital infections.

    Release date:2024-04-25 02:18 Export PDF Favorites Scan
  • STUDY ON RISK FACTORS OF NONSYNDROMIC CLEFT LIP AND PALATE IN CHINESE GUANGDONG POPULATION

    Objective To investigate the association between environmental factors and nonsyndromic cleft lip and palate (NSCLP), and to explore the interaction of main risk factors in Chinese Guangdong population. Methods A hospital-based case-control study was used. NSCLP children were selected from Cleft Lip amp; Palate Treatment Centre of Second Affil iated Hospital of Medical College of Shantou University between September 2009 and March 2010 as cases. And controlswere chosen from other departments in the same hospital during the same period. The parents of cases and controls were inquired regarding the risk factors and the answers were filled in a unification questionnaire by physicians. These data were analysed with chi-square test and multivariate unconditional logistic regression analysis. Results A total of 105 cases and 110 controls with a mean age of 2.2 years and 3.0 years, respectively, were enrolled. Multivariate logistic regression analysis revealed that genetic family history (OR=4.210, P=0.039), mothers’ abnormal reproductive history (OR=2.494, P=0.033), early pregnancy medication (OR=3.488, P=0.000), and maternal stress (OR=3.416, P=0.011) were risk factors. There were positve interactions between genetic family history and mothers’ abnormal reproductive history as well as early pregnancy medication. Conclusion Certain influencing factors including genetic family history, mothers’ abnormal reproductive history, early pregnancy medication, and maternal stress are associated with NSCLP among Chinese Guangdong population. This study suggests that it may reduce the incidence rate of NSCLP through environmental intervention.

    Release date:2016-08-31 05:48 Export PDF Favorites Scan
  • Predictors of Generalized Anxiety Disorder among Teachers in 3 Months after the Lushan Earthquake

    ObjectiveTo evaluate the predictors of generalized anxiety disorder (GAD) among teachers in 3 months after Lushan earthquake. MethodsA prospective cohort study was conducted to diagnostically evaluate the psychological sequelae and GAD during 14-20 days and 85-95 days after the earthquake. The possible predictive factors of psychological sequelae were assessed by a self-made questionnaire and the GAD was assessed by the GAD symptom criterion of M.I.N.I. in 3 months. The univariate and multivariate logistic regression analysis (ULRA, MLRA) were applied to analyze the predictors of GAD after the two-staged assessments. ResultsThere were a total of 319 teachers completed the two-staged assessments. The total response rate was 51.3%. Seventy teachers were diagnosed as GAD and the prevalence of GAD in 3 months was 21.9%. The predictive factors by ULRA included:male, older than 35 years old, having unlivable house, living in tents, sleeping difficulties, easy to feel sad, physical discomfort, loss of appetite, feeling short of social support, unable to calm down for working, feeling difficult for teaching, observing more inattention of students, and wanting to ask for a leave. The independent predictors by MLRA included:male, having unlivable house, feeling short of social support, and feeling difficult for teaching. ConclusionThe teachers have a higher likelihood of GAD after earthquake. It is essential to pay more attention to those male teachers, who feel short of social support and don't have a livable house thus to prevent the GAD at the early stage of post-earthquake.

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