Low statistical power undermines the purpose of scientific research; it reduces the chance of detecting a true effect. Perhaps less intuitively, low power also reduces the likelihood that a ...

Based on onboard water samples gathered over three years, the report evaluated airlines for contamination, federal safety ...

In a clinical research program involving genetic analysis, the taking of a blood or tissue sample for analysis may be the first and only physical involvement of a subject in the genetic aspects of the ...

The National Children's Study (NCS) is a longitudinal, observational, birth-cohort study that will seek to identify the foundations of healthy adulthood by examining the effects of a broad range of ...

Pew Research Center designed this study to assess the current state of online survey sampling methods – both probability-based and opt-in – and determine their accuracy on general population estimates ...