Background The study objective was to compare the Newcastle–Ottawa Scale (NOS) and
the RTI item bank (RTI-IB) and estimate interrater agreement using the RTI-IB within a …

OBJECTIVE: Large health care utilization databases are frequently used in variety of
settings to study the use and outcomes of therapeutics. Their size allows the study of …

A goal of many health studies is to determine the causal effect of a treatment or intervention
on health outcomes. Often, it is not ethically or practically possible to conduct a perfectly …

Background Nonexperimental studies are increasingly used to investigate the safety and
effectiveness of medical products as they are used in routine care. One of the primary …

Background: Adjusting for large numbers of covariates ascertained from patients' health care
claims data may improve control of confounding, as these variables may collectively be …

Importance Radioactive iodine (RAI) has been used extensively to treat hyperthyroidism
since the 1940s. Although widely considered a safe and effective therapy, RAI has been …

The concept of bias is the lack of internal validity or incorrect assessment of the association
between an exposure and an effect in the target population in which the statistic estimated …

Background—Current observational studies on warfarin use and the risk for stroke and
bleeding in patients with atrial fibrillation (AF) undergoing dialysis found conflicting results …

Background Large health care utilization databases are frequently used to analyze
unintended effects of prescription drugs and biologics. Confounders that require detailed …

Background A number of recent case reports and series have identified a subgroup of
atypical fractures of the femoral shaft associated with bisphosphonate use. A population …