Skip to main content

Advertisement

Table 2 A hypothetical population without bias

From: Detecting and correcting the bias of unmeasured factors using perturbation analysis: a data-mining approach

Level of U (i) Population number (m i ) U is associated with neither E nor D U is not associated with E U is not associated with D
Exposure prevalence (p i ) Disease risk among the unexposed ( r i u ) Relative risk ( r i e / r i u ) Exposure prevalence (p i ) Disease risk among the unexposed ( r i u ) Relative risk ( r i e / r i u ) Exposure prevalence (p i ) Disease risk among the unexposed ( r i u ) Relative risk ( r i e / r i u )
1 3,000 0.40 0.30 1.50 0.40 0.40 1.54 0.80 0.30 1.50
2 2,500 0.40 0.30 1.50 0.40 0.30 1.52 0.60 0.30 1.50
3 2,500 0.40 0.30 1.50 0.40 0.25 1.45 0.40 0.30 1.50
4 2,000 0.40 0.30 1.50 0.40 0.20 1.42 0.20 0.30 1.50
Total 10,000 Crude relative risk (crude RR) = 1.50 Crude relative risk (crude RR) = 1.50 Crude relative risk (crude RR) = 1.50
Standardized relative risk (SRR) = 1.50 Standardized relative risk (SRR) = 1.50 Standardized relative risk (SRR) = 1.50