Skip to main content

Table 3 Cost coefficients for different types of misclassification

From: Power and sample size calculations in the presence of phenotype errors for case/control genetic association studies

K

R*

p

C θ

C φ

0.005

0.5

0.05

0.01

540.29

  

0.15

0.01

458.99

 

1

0.05

0.01

478.32

  

0.15

0.01

432.67

 

2

0.05

0.01

440.18

  

0.15

0.01

415.60

0.05

0.5

0.05

0.09

51.59

  

0.15

0.10

43.82

 

1

0.05

0.08

45.67

  

0.15

0.10

41.31

 

2

0.05

0.08

42.03

  

0.15

0.10

39.68

  1. The column heading for this table are as follows: K = prevalence; R* = ratio of controls to cases; p = SNP minor allele frequency in affected population; C θ = Cost coefficient corresponding to misclassification parameter θ – this is a lower bound of the percent increase in sample size necessary to maintain constant asymptotic power for every 1% increase in θ C φ = Cost coefficient corresponding to misclassification parameter φ – this is a lower bound of the percent increase in sample size necessary to maintain constant asymptotic power for every 1% increase in φ. The cost coefficients are computed using equation (1).