Summary. Nonparametric methods have attracted less attention than their parametric counterparts for cure rate analysis. In this paper, we study a general nonparametric mixture model. The proportional hazards assumption is employed in modeling the effect of covariates on failure time patients who are not cured. EM algorithm, marginal likelihood approach, and multiple imputations to estimate parameters interest This model extends models improves estimation proposed by other researchers. It...

Abstract The Ontario Cancer Registry (OCR) and the Surveillance, Epidemiology End Results (SEER) databases were used to describe temporal trends in incidence survival of squamous cancers upper aerodigestive tract (UADT) US between 1984 2001. Between 1984–86 1999–01 periods, age‐adjusted rate all first primary UADT decreased from 11.6 (11.2–12.0) 8.8 (8.5–9.1) 13.0 (12.7–13.3) 10.2 (10.0–10.4) US. Significant decreases observed many sites but there was no significant change cancer oropharynx...

Cure rate estimation is an important issue in clinical trials for diseases such as lymphoma and breast cancer mixture models are the main statistical methods. In last decade, under different distributions, exponential, Weibull, log-normal Gompertz, have been discussed used. However, these involve stronger distributional assumptions than desirable inferences may not be robust to departures from assumptions. this paper, a model proposed using generalized F distribution family. Although family...

Cure rate estimation is an important issue in clinical trials for diseases such as lymphoma and breast cancer mixture models are the main statistical methods. In last decade, under different distributions, exponential, Weibull, log-normal Gompertz, have been discussed used. However, these involve stronger distributional assumptions than desirable inferences may not be robust to departures from assumptions. this paper, a model proposed using generalized F distribution family. Although family...

BACKGROUND Practice guidelines recommend neoadjuvant chemotherapy (NACT) for bladder cancer. However, the evidence in support of adjuvant (ACT) is less robust. Here we describe whether efficacy NACT/ACT was sufficient to change clinical practice and demonstrated trials translated into effectiveness general population. METHODS Electronic records treatment were linked population‐based Ontario Cancer Registry identify all patients with cancer treated cystectomy 1994‐2008. Utilization compared...

Non-small-cell lung cancer (NSCLC) is predominantly a disease of the elderly. Retrospective analyses National Cancer Institute Canada Clinical Trials Group JBR.10 trial and Lung Adjuvant Cisplatin Evaluation (LACE) meta-analysis suggest that elderly benefit from adjuvant chemotherapy. However, were under-represented in these studies, raising concerns regarding reproducibility study results clinical practice.By using Ontario Registry, we identified 6,304 patients with NSCLC who treated...

In this article, we present a frailty model using the generalized gamma distribution as distribution. It is power generalization of popular model. also includes other models such lognormal and Weibull special cases. The flexibility makes it possible to detect complex structure which may otherwise be missed. Due intractable integrals in likelihood function its derivatives, propose approximate either by Monte Carlo simulation or quadrature method then determine maximum estimates parameters We...

Abstract The proportional hazard (PH) mixture cure model and the accelerated failure time (AFT) are usually used in analysing data with long‐term survivors. However, semiparametric AFT has attracted less attention than PH because of complexity its estimation method. In this paper, we propose a new method for model. This employs EM algorithm rank estimator to estimate parameters interest. M‐step algorithm, which incorporates rank‐like estimating equation, can be carried out easily using...

Abstract We propose a nonparametric method to assess the effects of one or more covariates on cure rate for survival data with fraction. The extends existing work single sample and multiple cases also allows continuous covariate. proposed estimator is shown be consistent asymptotically normal. A simulation study shows that estimates covariate effect smaller biases than semi‐parametric models, particularly when models mis‐specify effect. applied leukaemia patients age chance being cured after...

Background: International guidelines recommend adjuvant chemotherapy (ACT) for patients with stage III colon cancer. Whether efficacy observed in clinical trials translates to effectiveness routine practice is less well understood. Here we describe use and outcomes of ACT practice. Methods: All cases cancer treated surgery Ontario 2002–2008 were identified using the population-based Cancer Registry. Linked electronic records treatment use. Pathology reports obtained a random 25% sample all...

Few studies have investigated the risks of developing intubation and death in patients seen emergency department (ED) with COVID-19 pre-existing asthma. We conducted a retrospective cohort study using data from Canadian Emergency Department Rapid Response Network (CCEDRRN) March 1st, 2020, to December 31st, 2021. Inclusion criteria were age ≥18 positive SARS-CoV-2 test. The primary outcome was composite or death, secondary severe COVID-19, as defined by World Health Organization....

Since 2004, several clinical trials have demonstrated that adjuvant chemotherapy (ACT) improves survival in patients with early-stage non-small-cell lung cancer (NSCLC). Here, we evaluate the uptake of ACT and its impact on outcomes general population Ontario, Canada.All diagnosed NSCLC Ontario from 2001 to 2006 who underwent surgical resection (n = 6,304) were identified using Cancer Registry. We linked electronic records treatment registry. described compared all surgically resected 2003...

The time interval between surgery and initiation of adjuvant chemotherapy (ACT) may impact survival in colorectal breast cancers. This is the first report describing association to (TTAC) non-small cell lung cancer (NSCLC).All cases NSCLC diagnosed Ontario, Canada, from 2004 2006 who underwent surgical resection (n = 3354) were identified using Ontario Cancer Registry. TTAC was defined as dates ACT. Factors associated with greater than 10 weeks evaluated by logistic regression. Cox...