Table 9 

Quantitative assessments of model adequacy. 

ShapiroWilks normality test performed on standardized residuals. 



W 
P 



Without outlier 
0.984 
0.06 

With outlier 
0.960 
0.0001 

T test to see if mean of standardized residuals was not zero. 

Mean 
T 
df 
P 

Without outlier 
0.003 
0.03 
158 
0.97 
With outlier 
0.003 
0.03 
159 
0.97 
Bartlett's test to see if the standardized residuals, divided into four groups by their corresponding fitted values, lacked constant variances. 

K^{2} 
Df 
P 

Without outlier 
4.43 
3 
0.22 

With outlier 
15.02 
3 
0.002 



Wachtel et al. BMC Cancer 2006 6:65 doi:10.1186/14712407665 