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Table 4 Illustrative examples of FIS and SCDS BNT results corrected for selection bias.

From: Estimating uncertainty in observational studies of associations between continuous variables: example of methylmercury and neuropsychological testing in children

Scenario

Shift in Exposurea

Shift in outcomeb

Slope multiplierc

Regression slope

    

Observed

Corrected

FIS

     

Scenario 1

5%

10%

2.0

-0.019

-0.024

Scenario 2

5%

-10%

0.0

-0.019

-0.013

Scenario 3

-5%

-10%

1.5

-0.019

-0.021

Scenario 4

-5%

10%

2.0

-0.019

-0.027

Scenario 5

10%

10%

0.5

-0.019

-0.013

Scenario 6

10%

-10%

1.5

-0.019

-0.025

Scenario 7

-10%

-10%

0.0

-0.019

-0.009

Scenario 8

-10%

10%

0.5

-0.019

-0.018

SCDS

     

Scenario 1

5%

10%

2.0

-0.012

0.008

Scenario 2

5%

-10%

0.0

-0.012

-0.016

Scenario 3

-5%

-10%

1.5

-0.012

-0.004

Scenario 4

-5%

10%

2.0

-0.012

-0.030

Scenario 5

10%

10%

0.5

-0.012

0.014

Scenario 6

10%

-10%

1.5

-0.012

-0.037

Scenario 7

-10%

-10%

0.0

-0.012

0.017

Scenario 8

-10%

10%

0.5

-0.012

-0.031

  1. a Difference (expressed as a percent change) between the mean exposure among the sampled subjects (s) compared to the entire target population which includes both sampled and non-sampled subjects (s+n)
  2. b Difference (expressed as a percent change) between the mean outcome measure among the sampled subjects (s) compared to the entire target population which includes both sampled an non sampled subjects (s+n)
  3. cSlope modifier (ν) was used to allow for scenarios where the regression slope based on the non-sampled subjects was different from the slope based on the sampled subjects: bn = νbs