There are certain assumptions about the baseline distribution and distribution of frailty. Mostly Weibull distribution is considered for baseline hazard but we consider some different baseline distributions. Mostly assumption of gamma distribution is considered for frailty distribution. In this paper also, we consider gamma distribution as frailty distribution and two different baseline distrib...

OBJECTIVE First, we tested the hypothesis that the rate of change of physical frailty and cognitive function in older adults are correlated. Next, we examined if their rates of change are associated with the same brain pathologies. METHODS About 2,167 older adults participating in the Religious Orders Study and the Rush Memory and Aging Project had annual clinical evaluations. Bivariate rando...

BACKGROUND The immune and blood coagulation systems have been implicated in the pathophysiology of the geriatric syndrome of frailty, but limited prospective data examining the relationship of clotting/inflammation biomarkers to risk of incident frailty exist. METHODS This prospective analysis was derived from a nested case-control study within the Women's Health Initiative. Among women 65 to...

Many analysis in epidemiological and prognostic studies and in studies of event history data require methods that allow for unobserved covariates or “frailties”. We consider the shared frailty model in the frame work of parametric proportional hazard model. There are certain assumptions about the distribution of frailty and baseline distribution. Mostly gamma distribution is considered for frai...

BACKGROUND There is no single generally accepted clinical definition of frailty. Previously developed tools to assess frailty that have been shown to be predictive of death or need for entry into an institutional facility have not gained acceptance among practising clinicians. We aimed to develop a tool that would be both predictive and easy to use. METHODS We developed the 7-point Clinical F...

Due to the aging and increasingly complex nature of our patients, frailty has become a high-priority theme in cardiovascular medicine. Despite the recognition of frailty as a pivotal element in the evaluation of older adults with cardiovascular disease (CVD), there has yet to be a road map to facilitate its adoption in routine clinical practice. Thus, we sought to synthesize the existing body o...

Department of Statistics, University of Pune, Pune-411007, India. Email: david−[email protected]; richa−[email protected] Abstract In this paper, we consider two different shared frailty regression models under the assumption of Gompertz as baseline distribution. Mostly assumption of gamma distribution is considered for frailty distribution. To compare the results with gamma frailty model, ...

The shared frailty models allow for unobserved heterogeneity or for statistical dependence between observed survival data. The most commonly used estimation procedure in frailty models is the EM algorithm, but this approach yields a discrete estimator of the distribution and consequently does not allow direct estimation of the hazard function. We show how maximum penalized likelihood estimation...

BACKGROUND Multistate models have become increasingly useful to study the evolution of a patient's state over time in intensive care units ICU (e.g. admission, infections, alive discharge or death in ICU). In addition, in critically-ill patients, data come from different ICUs, and because observations are clustered into groups (or units), the observed outcomes cannot be considered as independen...

OBJECTIVES To determine the degree to which hyperglycemia predicts the development of frailty and lower extremity mobility limitations. DESIGN Secondary data analysis of longitudinal data collected in a prospective cohort study. SETTING Baltimore, Maryland. PARTICIPANTS Three hundred twenty-nine women from the Women's Health and Aging Study II aged 70 to 79 at baseline who had all variabl...