Chronic systematic inflammation and reduced immune system fitness are considered potential contributing factors to the development of age-related frailty, but the underlying mechanisms are poorly defined. This exploratory study aimed to identify frailty-related inflammatory markers and immunological phenotypes in a cohort of community-dwelling adults aged ≥ 55 years. Frailty was assessed using ...

BACKGROUND AND OBJECTIVES Uromodulin-associated kidney disease (UAKD) is an autosomal dominant disease caused by uromodulin (UMOD) gene mutations. This study explored genotype-phenotype correlations by examining the relationship between the type of UMOD mutation and the age at onset of ESRD. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS Extensive bibliographic research was used to ascertain pa...

Biomedical studies often collect multivariate event time data from multiple clusters (either subjects or groups) within each of which event times for individuals are correlated and the correlation may vary in different classes. In such survival analyses, heterogeneity among clusters for shared and specific classes can be accommodated by incorporating parametric frailty terms into the model. In ...

OBJECTIVE To discuss models of care for frail seniors provided in primary care settings and those developed by Canadian FPs. SOURCES OF INFORMATION Ovid MEDLINE and the Cochrane database were searched from 2010 to January 2014 using the terms models of care, family medicine, elderly, and geriatrics. MAIN MESSAGE New models of funding for primary care have opened opportunities for ways of ca...

Models of unobserved heterogeneity, or frailty as it is commonly known in survival analysis, can often be formulated as semiparametric mixture models and estimated by maximum likelihood as proposed by Robbins (1950) and elaborated by Kiefer and Wolfowitz (1956). Recent developments in convex optimization, as noted by Koenker and Mizera (2014b), have led to dramatic improvements in computational...

BACKGROUND Time to first pregnancy (TTFP) has never been studied in an Iranian setting. Lifestyle, occupational and environmental factors have been suggested to affect the female reproduction. OBJECTIVE This study was conducted to measure TTFP in the south of Iran and survey the effects of several similar factors on TTFP by frailty models. MATERIALS AND METHODS The data on TTFP were availab...

It is assumed for the Cox’s proportional hazards model that the survival times of subjects are independent. This assumption might be violated in some situations, in which the collected data are correlated. The well-known Cox model is not valid in this situation because independence assumption among individuals is violated. For this purpose Cox’s proportional hazard model is extent to the analys...