Background Systematic reviews and meta-analyses of observational studies are frequently
performed, but no widely accepted guidance is available at present. We performed a …

The Social Norms Approach is a widely used intervention strategy for promoting positive
health-related behaviors. The Approach operates on the premise that individuals …

INTRODUCTION: Insight into the characteristics of populations from which research samples
are drawn is essential to understanding the generalizability of research findings. This study …

Interrupted time series analysis differs from most other intervention study designs in that it
involves a before-after comparison within a single population, rather than a comparison with …

Much biomedical research is observational. The reporting of such research is often
inadequate, which hampers the assessment of its strengths and weaknesses and of a …

In the assessment of the effect of a treatment or potential risk factor—termed an exposure—
on a patient outcome, the possibility of confounding by other factors must be considered. 1 …

Los estudios observacionales (EO) corresponden a diseños de investigación cuyo objetivo
es" la observación y registro" de acontecimientos sin intervenir en el curso natural de estos …

Comments on the editorial by Peter Griffiths & Ian Norman (see record 2013-10991-001).
The editorial summarized many important points. The Medical Research Council guidance …

Abstract Background Randomised controlled trials (RCTs) are considered the gold standard
when evaluating the causal effects of healthcare interventions. When RCTs cannot be used …

Background: Propensity score (PS) analysis is increasingly being used in observational
studies, especially in some cancer studies where random assignment is not feasible. This …