A case-control study is a type of medical research investigation often used to help determine the cause of a disease, particularly when investigating a disease outbreak or rare condition. If public ...

This is a preview. Log in through your library . Abstract A multiple-imputation method is developed for analysing data from an observational study where some covariate values are not observed. A ...

Whereas cardiovascular disease-related mortality has declined in most developed countries, its known prevalence is increasing worldwide, although few data on the causes of heart disease in the ...

Thyroid carcinomas in children and adolescents are rare tumors and the most common among them is papillary thyroid cancer (PTC). Its etiology is still under research and has not been clearly defined ...

Objective Physical activity (PA) is associated with a decreased incidence of dementia, but much of the evidence comes from short follow-ups prone to reverse causation. This meta-analysis investigates ...

A systematic bibliographic search of the medical literature published from 1 January 1960 until 1 June 2009 was conducted through electronic databases including Medline and Latin America & Caribbean ...