Correcting the bias of the net benefit estimator due to right‐censored observations

2021 ◽  
Author(s):  
Julien Péron ◽  
Maryam Idlhaj ◽  
Delphine Maucort‐Boulch ◽  
Joris Giai ◽  
Pascal Roy ◽  
...  
Keyword(s):  
Net Benefit ◽  
Censored Observations

MODEL UNTUK UJI KUALITAS SISTEM INFORMASI UJIAN NASIONAL BERBASIS KOMPUTER TINGKAT SMA & MA

2018 ◽  
Vol 14 (2) ◽  
pp. 187
Author(s):  
Irwan Agus Sobari ◽  
Fajar Akbar ◽  
Robi Aziz Zauma ◽  
Amin Nur Rais
Keyword(s):  
Net Benefit

UNBK (Ujian Nasional Berbasis Komputer) adalah aplikasi ujian nasional yang berkembang yang telah mengklaim perhatian dan ketertarikan peneliti perkembangan ilmu komputer di dunia pendidikan. Salah satu perkembangan terbaru yang paling diterima di UNBK adalah kemanfaatan nya. Kami mengusulkan sebuah model model sukses DeLone & McLean IS untuk menganalisis kualitas UNBK pada kemanfaatan penggunanya. Pendekatan empiris didasarkan pada kuesioner survei online terhadap siswa SMA & MA, hasil feedback yang diterima sebanyak 74 individu. Hasilnya mengungkapkan bahwa Kualitas Informasi, Kualitias Sistem dan Kualitas pelayanan adalah preseden penting dari kepuasan pengguna, dan pentingnya kepuasan pengguna akan menghasilkan net benefit yang cukup signifikan. Memahami pentingnya konteks UNBK pada Net Benefit bagi pengguna berguna untuk memberikan wawasan baru kepada instansi terkait untuk menerapkan strategi untuk mempertahankan pengguna atau bahkan menarik pengadopsi potensial. penelitian ini memberikan implikasi teoritis dan praktis dari temuan penelitian.

Nitrogen Requirement of Potato for Eastern Indo-Gangatic Plain of India

2020 ◽  
Vol 7 (03) ◽  
Author(s):  
S. K. YADAV ◽  
R. K. SINGH ◽  
V. K. DUA ◽  
S SINGH ◽  
SARALA YADAV ◽  
...  
Keyword(s):  
Tuber Yield ◽  
Potato Crop ◽  
Block Design ◽  
Nitrogen Level ◽  
Cost Ratio ◽  
Research Station ◽  
Net Benefit ◽  
Marketable Tuber ◽  
Benefit Cost Ratio ◽  
Significant Difference

A field experiment was carried out during 2015-16 and 2016-17 at ICAR-Central Potato Research Station, Patna, Bihar, in randomized block design with four replications with objective to quantity the optimum requirement of nitrogen to potato crop. Significantly the highest plant height was recorded with nitrogen level of 300 kg/ha. Distributions of the smallest size of tuber yield of potato were decreasing with increasing the level of nitrogen. There was about 26.0% more yield of the smallest size tuber of potato was recorded with zero nitrogen as compare to the highest level of nitrogen i.e. 300 kg/ha. Increasing the nitrogen over the level of 150 to 225 kg per hectare, increasing the yield of tuber gradually slower rate than nitrogen level from 0 to 150 kg/ha. Total and marketable tuber yield of potato were increasing significantly with increasing level of nitrogen up to 150 kg/ha. There was no significant difference in marketable tuber yield was found for nitrogen level between 150 and 225 kg/ha. Highest (1.66) net benefit cost ratio was also recorded with level of nitrogen @ 150 kg/ha in potato. Hence, application of nitrogen @ 150 kg/ha was found statistically and economically more beneficial for potato cultivation in Eastern Indo-Gangatic plain of India.

scholarly journals Reproductive Performance and Partial Budget Analysis of a Prostaglandin or a Modified Ovsyn3ch Protocol in Autumn Calving Dairy Herds

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1031
Author(s):  
George Lindley ◽  
Jim Willshire ◽  
Steven Van Winden
Keyword(s):  
Relative Effectiveness ◽  
Dairy Herds ◽  
Net Benefit ◽  
Start Date ◽  
Budget Analysis ◽  
Partial Budget ◽  
Holstein Friesian ◽  
Input Variables ◽  
Input Uncertainties ◽  
Relative Profitability

In autumn calving dairy herds, treatment of cattle not observed in estrus prior to the breeding season is common. Routinely, a single prostaglandin or a modified Ovsynch (MOFT) protocol are used—without evidence of their relative effectiveness. This study compares the effects on conception, associated timing, and profitability of administering cows with prostaglandin or MOFT treatment. A hundred and ninety-two Holstein-Friesian cows from three herds without an observed estrus within 28-days before mating start date were randomly treated with d-cloprostenol (PGOD) or an 8-day MOFT protocol. The association of treatment and calving-breeding start-date interval (CBSI) on the risk of conception were investigated. Partial budget, sensitivity analysis, and Monte Carlo simulation was used to assess economic performance, identify critical input variables, and explore the effects of input uncertainties on model output. There was a significant association between MOFT treatment and conception during 21 and 84 days after mating start date, compared to PGOD. MOFT treatment was associated with a mean net benefit of £58.21 (sd £19.42) and £27.29 (sd £17.75) per cow for herds with a fixed or variable dry-off date, respectively. The relative profitability of an MOFT protocol is dependent on its effects on barren rate and herd dry-off strategy.

scholarly journals Zero-inflated-censored Weibull and gamma regression models to estimate wild boar population dispersal distance

2021 ◽  
Author(s):  
Eduardo de Freitas Costa ◽  
Silvana Schneider ◽  
Giulia Bagatini Carlotto ◽  
Tainá Cabalheiro ◽  
Mauro Ribeiro de Oliveira Júnior
Keyword(s):  
Wild Boar ◽  
Regression Models ◽  
Likelihood Function ◽  
Complex Structure ◽  
Dispersal Distance ◽  
Wild Boar Population ◽  
Gamma Distributions ◽  
Excess Of Zeros ◽  
Censored Observations ◽  
Positive Effect

AbstractThe dynamics of the wild boar population has become a pressing issue not only for ecological purposes, but also for agricultural and livestock production. The data related to the wild boar dispersal distance can have a complex structure, including excess of zeros and right-censored observations, thus being challenging for modeling. In this sense, we propose two different zero-inflated-right-censored regression models, assuming Weibull and gamma distributions. First, we present the construction of the likelihood function, and then, we apply both models to simulated datasets, demonstrating that both regression models behave well. The simulation results point to the consistency and asymptotic unbiasedness of the developed methods. Afterwards, we adjusted both models to a simulated dataset of wild boar dispersal, including excess of zeros, right-censored observations, and two covariates: age and sex. We showed that the models were useful to extract inferences about the wild boar dispersal, correctly describing the data mimicking a situation where males disperse more than females, and age has a positive effect on the dispersal of the wild boars. These results are useful to overcome some limitations regarding inferences in zero-inflated-right-censored datasets, especially concerning the wild boar’s population. Users will be provided with an R function to run the proposed models.

scholarly journals Clinical use of the SelectMDx urinary-biomarker test with or without mpMRI in prostate cancer diagnosis: a prospective, multicenter study in biopsy-naïve men

2021 ◽  
Author(s):  
Rianne J. Hendriks ◽  
Marloes M. G. van der Leest ◽  
Bas Israël ◽  
Gerjon Hannink ◽  
Anglita YantiSetiasti ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Risk Stratification ◽  
Specific Antigen ◽  
Low Grade ◽  
Diagnostic Study ◽  
High Grade ◽  
Net Benefit ◽  
Conditional Strategy ◽  
Detection Rates ◽  
Guided Biopsy

Abstract Background Risk stratification in men with suspicion of prostate cancer (PCa) requires reliable diagnostic tests, not only to identify high-grade PCa, also to minimize the overdetection of low-grade PCa, and reduction of “unnecessary” prostate MRIs and biopsies. This study aimed to evaluate the SelectMDx test to detect high-grade PCa in biopsy-naïve men. Subsequently, to assess combinations of SelectMDx test and multi-parametric (mp) MRI and its potential impact on patient selection for prostate biopsy. Methods This prospective multicenter diagnostic study included 599 biopsy-naïve patients with prostate-specific antigen level ≥3 ng/ml. All patients underwent a SelectMDx test and mpMRI before systematic transrectal ultrasound-guided biopsy (TRUSGB). Patients with a suspicious mpMRI also had an in-bore MR-guided biopsy (MRGB). Histopathologic outcome of TRUSGB and MRGB was used as reference standard. High-grade PCa was defined as ISUP Grade Group (GG) ≥ 2. The primary outcome was the detection rates of low- and high-grade PCa and number of biopsies avoided in four strategies, i.e., (1) SelectMDx test-only, (2) mpMRI-only, (3) SelectMDx test followed by mpMRI when SelectMDx test was positive (conditional strategy), and (4) SelectMDx test and mpMRI in all (joint strategy). A positive SelectMDx test outcome was a risk score of ≥−2.8. Decision curve analysis (DCA) was performed to assess clinical utility. Results Prevalence of high-grade PCa was 31% (183/599). Thirty-eight percent (227/599) of patients had negative SelectMDx test in whom biopsy could be avoided. Low-grade PCa was not detected in 35% (48/138) with missing 10% (18/183) high-grade PCa. Yet, mpMRI-only could avoid 49% of biopsies, not detecting 4.9% (9/183) of high-grade PCa. The conditional strategy reduces the number of mpMRIs by 38% (227/599), avoiding biopsy in 60% (357/599) and missing 13% (24/183) high-grade PCa. Low-grade PCa was not detected in 58% (80/138). DCA showed the highest net benefit for the mpMRI-only strategy, followed by the conditional strategy at-risk thresholds >10%. Conclusions SelectMDx test as a risk stratification tool for biopsy-naïve men avoids unnecessary biopsies in 38%, minimizes low-grade PCa detection, and misses only 10% high-grade PCa. Yet, using mpMRI in all patients had the highest net benefit, avoiding biopsy in 49% and missing 4.9% of high-risk PCa. However, if mpMRI availability is limited or expensive, using mpMRI-only in SelectMDx test positive patients is a good alternative strategy.

scholarly journals Development and validation of a clinical prediction rule for development of diabetic foot ulceration: an analysis of data from five cohort studies

2021 ◽  
Vol 9 (1) ◽  
pp. e002150
Author(s):  
Francesca M Chappell ◽  
Fay Crawford ◽  
Margaret Horne ◽  
Graham P Leese ◽  
Angela Martin ◽  
...  
Keyword(s):  
Cohort Studies ◽  
Secondary Care ◽  
Prediction Rule ◽  
Clinical Prediction Rule ◽  
Initial Assessment ◽  
Validation Dataset ◽  
Benefit Analysis ◽  
Clinical Prediction ◽  
Net Benefit ◽  
Foot Ulceration

IntroductionThe aim of the study was to develop and validate a clinical prediction rule (CPR) for foot ulceration in people with diabetes.Research design and methodsDevelopment of a CPR using individual participant data from four international cohort studies identified by systematic review, with validation in a fifth study. Development cohorts were from primary and secondary care foot clinics in Europe and the USA (n=8255, adults over 18 years old, with diabetes, ulcer free at recruitment). Using data from monofilament testing, presence/absence of pulses, and participant history of previous ulcer and/or amputation, we developed a simple CPR to predict who will develop a foot ulcer within 2 years of initial assessment and validated it in a fifth study (n=3324). The CPR’s performance was assessed with C-statistics, calibration slopes, calibration-in-the-large, and a net benefit analysis.ResultsCPR scores of 0, 1, 2, 3, and 4 had a risk of ulcer within 2 years of 2.4% (95% CI 1.5% to 3.9%), 6.0% (95% CI 3.5% to 9.5%), 14.0% (95% CI 8.5% to 21.3%), 29.2% (95% CI 19.2% to 41.0%), and 51.1% (95% CI 37.9% to 64.1%), respectively. In the validation dataset, calibration-in-the-large was −0.374 (95% CI −0.561 to −0.187) and calibration slope 1.139 (95% CI 0.994 to 1.283). The C-statistic was 0.829 (95% CI 0.790 to 0.868). The net benefit analysis suggested that people with a CPR score of 1 or more (risk of ulceration 6.0% or more) should be referred for treatment.ConclusionThe clinical prediction rule is simple, using routinely obtained data, and could help prevent foot ulcers by redirecting care to patients with scores of 1 or above. It has been validated in a community setting, and requires further validation in secondary care settings.

scholarly journals Head-to-Head Comparison of Two Nomograms Predicting Probability of Lymph Node Invasion in Prostate Cancer and the Therapeutic Impact of Higher Nomogram Threshold

2021 ◽  
Vol 10 (5) ◽  
pp. 999
Author(s):  
Zilvinas Venclovas ◽  
Tim Muilwijk ◽  
Aivaras J. Matjosaitis ◽  
Mindaugas Jievaltas ◽  
Steven Joniau ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Lymph Node ◽  
Area Under The Curve ◽  
Pelvic Lymph Node ◽  
Cancer Center ◽  
Study Cohort ◽  
Net Benefit ◽  
Characteristic Analysis ◽  
Therapeutic Impact ◽  
Mskcc Nomogram

Introduction: The aim of the study was to compare the performance of the 2012 Briganti and Memorial Sloan Kettering Cancer Center (MSKCC) nomograms as a predictor for pelvic lymph node invasion (LNI) in men who underwent radical prostatectomy (RP) with pelvic lymph node dissection (PLND), to examine their performance and to analyse the therapeutic impact of using 7% nomogram cut-off. Materials and Methods: The study cohort consisted of 807 men with clinically localised prostate cancer (PCa) who underwent open RP with PLND between 2001 and 2019. The area under the curve (AUC) of the receiver operator characteristic analysis was used to quantify the accuracy of the 2012 Briganti and MSKCC nomograms to predict LNI. Calibration plots were used to visualise over or underestimation by the models and a decision curve analysis (DCA) was performed to evaluate the net benefit associated with the used nomograms. Results: A total of 97 of 807 patients had LNI (12%). The AUC of 2012 Briganti and MSKCC nomogram was 80.6 and 79.2, respectively. For the Briganti nomogram using the cut-off value of 7% would lead to reduce PLND in 47% (379/807), while missing 3.96% (15/379) cases with LNI. For the MSKCC nomogram using the cut-off value of 7% a PLND would be omitted in 44.5% (359/807), while missing 3.62% (13/359) of cases with LNI. Conclusions: Both analysed nomograms demonstrated high accuracy for prediction of LNI. Using a 7% nomogram cut-off would allow the avoidance up to 47% of PLNDs, while missing less than 4% of patients with LNI.

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