6 research outputs found
School System Evaluation By Value-Added Analysis under Endogeneity
No full textValue-added analysis is a common tool in analysing school performances. In this paper, we analyse the SIMCE panel data which provides individual scores of about 200,000 students in Chile, and whose aim is to rank schools according to their educational achievement. Based on the data collection procedure and on empirical evidences, we argue that the exogeneity of some covariates is questionable. This means that a nonvanishing correlation appears between the school-specific effect and some covariates. We show the impact of this phenomenon on the calculation of the value-added and on the ranking, and provide an estimation method that is based on instrumental variables in order to correct the bias of endogeneity. Revisiting the definition of the value-added, we propose a new calculation robust to endogeneity that we illustrate on the SIMCE data.
Image_1_The Value of Preoperative Local Symptoms in Prognosis of Upper Tract Urothelial Carcinoma After Radical Nephroureterectomy: A Retrospective, Multicenter Cohort Study.tiff
No full textPurposeWe aimed to evaluate the impact of preoperative local symptoms on prognosis after radical nephroureterectomy in patients with upper tract urothelial carcinoma (UTUC).MethodsThis retrospective study consisted of 2,662 UTUC patients treated at 15 institutions in Taiwan from 1988 to 2019. Clinicopathological data were retrospectively collected for analysis by the Taiwan UTUC Collaboration Group. The Kaplan-Meier method was used to calculate overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and bladder recurrence-free survival (BRFS). The prognostic value of preoperative local symptoms in OS, CSS, DFS, and BRFS was investigated using Cox proportional hazards models.ResultsThe median follow-up was 36.6 months. Among 2,662 patients, 2,130 (80.0%) presented with hematuria and 398 (15.0%) had symptomatic hydronephrosis at diagnosis. Hematuria was associated with less symptomatic hydronephrosis (p ConclusionsPreoperative local symptoms were significantly associated with oncological outcomes, whereas symptomatic hydronephrosis and hematuria had opposite prognostic effects. Preoperative symptoms may provide additional information on risk stratification and perioperative treatment selection for patients with UTUC.</p
Table_1_The Value of Preoperative Local Symptoms in Prognosis of Upper Tract Urothelial Carcinoma After Radical Nephroureterectomy: A Retrospective, Multicenter Cohort Study.pdf
No full textPurposeWe aimed to evaluate the impact of preoperative local symptoms on prognosis after radical nephroureterectomy in patients with upper tract urothelial carcinoma (UTUC).MethodsThis retrospective study consisted of 2,662 UTUC patients treated at 15 institutions in Taiwan from 1988 to 2019. Clinicopathological data were retrospectively collected for analysis by the Taiwan UTUC Collaboration Group. The Kaplan-Meier method was used to calculate overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and bladder recurrence-free survival (BRFS). The prognostic value of preoperative local symptoms in OS, CSS, DFS, and BRFS was investigated using Cox proportional hazards models.ResultsThe median follow-up was 36.6 months. Among 2,662 patients, 2,130 (80.0%) presented with hematuria and 398 (15.0%) had symptomatic hydronephrosis at diagnosis. Hematuria was associated with less symptomatic hydronephrosis (p ConclusionsPreoperative local symptoms were significantly associated with oncological outcomes, whereas symptomatic hydronephrosis and hematuria had opposite prognostic effects. Preoperative symptoms may provide additional information on risk stratification and perioperative treatment selection for patients with UTUC.</p
Image_1_Impact of Adjuvant Chemotherapy on Variant Histology of Upper Tract Urothelial Carcinoma: A Propensity Score-Matched Cohort Analysis.tif
No full textBackgroundThe advantage of adjuvant chemotherapy for upper urinary tract urothelial cancer (UTUC) has been reported, whereas its impact on upper tract cancer with variant histology remains unclear. We aimed to answer the abovementioned question with our real-world data.Design, Setting, and ParticipantsPatients who underwent radical nephroureterectomy (RNU) and were confirmed to have variant UTUC were retrospectively evaluated for eligibility of analysis. In the Taiwan UTUC Collaboration database, we identified 245 patients with variant UTUC among 3,109 patients with UTUC who underwent RNU after excluding patients with missing clinicopathological information.InterventionThose patients with variant UTUC were grouped based on their history of receiving adjuvant chemotherapy or not.Outcome Measurements and Statistical AnalysisPropensity score matching was used to reduce the treatment assignment bias. Multivariable Cox regression model was used for the analysis of overall, cancer-specific, and disease-free survival.Results and LimitationsFor the patients with variant UTUC who underwent adjuvant chemotherapy compared with those without chemotherapy, survival benefit was identified in overall survival in univariate analysis (hazard ratio (HR), 0.527; 95% confidence interval (CI), 0.285–0.973; p = 0.041). In addition, in multivariate analysis, patients with adjuvant chemotherapy demonstrated significant survival benefits in cancer-specific survival (OS; HR, 0.454; CI, 0.208–0.988; p = 0.047), and disease-free survival (DFS; HR, 0.324; 95% CI, 0.155–0.677; (p = 0.003). The main limitations of the current study were its retrospective design and limited case number.ConclusionsAdjuvant chemotherapy following RNU significantly improved cancer-related survivals in patients with UTUC with variant histology.</p
DataSheet_1_Preoperative hydronephrosis is an independent protective factor of renal function decline after nephroureterectomy for upper tract urothelial carcinoma.pdf
No full textObjectivesTo evaluate the predictive role of pre-nephroureterectomy (NU) hydronephrosis on post-NU renal function (RF) change and preserved eligibility rate for adjuvant therapy in patients with upper tract urothelial carcinoma (UTUC).Patients and methodsThis retrospective study collected data of 1018 patients from the Taiwan UTUC Collaboration Group registry of 26 institutions. The patients were divided into two groups based on the absence or presence of pre-NU hydronephrosis. Estimated glomerular filtration rate (eGFR) was calculated pre- and post-NU respectively. The one month post-NU RF change, chronic kidney disease (CKD) progression, and the preserved eligibility rate for adjuvant therapy were compared for each CKD stage.Results404 (39.2%) patients without and 614 (60.8%) patients with pre-NU hydronephrosis were enrolled. The median post-NU change in the eGFR was significantly lower in the hydronephrosis group (-3.84 versus -12.88, pConclusionPre-NU hydronephrosis is an independent protective predictor for post-NU RF decline, CKD progression, and eligibility for adjuvant therapy. With cautious selection for those unfavorably prognostic, non-metastatic UTUC patients with preoperative hydronephrosis, adjuvant rather than neoadjuvant therapy could be considered due to higher chance of preserving eligibility.</p
