We have described the application of MSM to combat time-dependent confounding variable
. The impact of time-dependent confounding is an important issue that must be seriously considered by researchers analyzing data from longitudinal observational studies with time-varying exposures.
Possibility#3: There is a third variable -- a confounding variable
-- which causes the increase in BOTH ice cream sales AND murder rates.
Race and overall GPA were found to be confounding variables
and their effects were therefore statistically removed in analyses.
The 2 measures of patient-centeredness were correlated with the outcomes of visits, adjusting for the clustering of patients by physician and controlling for confounding variables
Finally, physician practice location was identified by Dr Glaser as an additional confounding variable
. We agree that selecting community physicians from one location (northern Colorado) to compare with fellowship-trained physicians drawn from throughout the United States and Canada could have affected the results, although we have no specific reason to believe this variable would affect the level of physician involvement.
The researchers noted previous evidence that a lower prevalence of breastfeeding in blacks, compared with other ethnicities, might be a confounding variable
, but they said that the overall presence of a protective effect of breast-feeding against type 2 diabetes suggests that all populations might benefit it.
The second generation of pregnant women more often had high depressive symptom scores (relative risk, 1.51); the difference was not changed substantially with imputation for missing confounding variable
data and adjustment for confounding variables
The other first-stage model relates a putative confounding variable
"Their study ends at age 55; that's where our study begins.' And many more of the nurses had a history of oral contraceptive use, a possible confounding variable
, than the Framingham women.
One problem with some of the previous data, however, was that a possible confounding variable
was not controlled: The injury or illness itself may have caused people to become depressed.
OC use therefore may represent a confounding variable
in previous sleep studies that compare healthy and depressed patients, said Dr.
Investigators also assessed each participant's diet to evaluate their calcium intake as a potential confounding variable