Moreover, two nonsignificant studies would be enough to nullify the association.
Thus, the adjustment for age would be expected to nullify the association between low eGFR and cataract strongly, given the already well known relationship between age and cataract.
We acknowledge that measurement error remains in our smoking assessment, and it is possible that a more perfect assessment could further attenuate or nullify this association.
The authors of this study subsequently demonstrated that the level of nondifferential asthma misclas-sification present in the Danish National Registry of Patients was not sufficient to nullify the association between asthma and various skin cancers that they examined.
Multivariate adjustment for other available confounders such as various forms of tobacco use, BMI, religion and mother tongue attenuated HRs but did not nullify the association for all-cause as well as CVD mortality in men and women.
However, as adjusting for confounding factors nullifies this association, we find no evidence for a unique association between cortisol and depression at either time point.
However, further adjustment for year of conception essentially nullified the association (adjusted OR = 0.98; 95% CI, 0.91 1.06).
Having nullified the association between C and D, how can matching result in net bias?
study 14 nullified the association with a new summary RR of 0.90 (95% CI: 0.77 to 1.05).
Additional adjustment for BMI nullified the association with CHF (0.97 [0.75–1.24]) but only modestly attenuated the relation to CVD incidence (1.23 [1.00–1.51], P = 0.052).
However, removing Connecticut and Massachusetts almost doubled the meta-regression coefficient for the PM2.5 PM10 ratio and nullified the association for median PM2.5 exposure levels, and the meta-regression estimate for median PM2.5 exposure levels was null after New Jersey was excluded.
