Risk of bias in observational studies using routinely collected data of comparative effectiveness research: a meta-research study.
Van Thu NguyenMishelle EngletonMauricia DavisonPhilippe RavaudRaphael PorcherIsabelle BoutronPublished in: BMC medicine (2021)
Reporting of essential information of study design in observational studies remained suboptimal. Selection bias and immortal time bias were common methodological issues that researchers and physicians should be aware of when interpreting the results of observational studies using routinely collected data.