Table 2 

Variations in mean IQ, standard deviations and mortality rates: their affect on sample size calculation. 

Total trial size required assuming: 



30% mortality 
35% mortality 



Mean IQ in control group 
SD 
Mean IQ in cooled group 
SD 
Mean difference 
Number required to detect this difference (80% power, 5% siq.) 
80% follow up 
75% follow up 
80% follow up 
75% follow up 


75 
15 
82.5 
15 
7.5 
126 
225 
240 
243 
259 
80 
15 
87.5 
15 
7.5 

85 
15 
92.5 
15 
7.5 

75 
20 
82.5 
20 
7.5 
224 
400 
427 
431 
460 
80 
20 
87.5 
20 
7.5 

85 
20 
92.5 
20 
7.5 

75 
25 
82.5 
25 
7.5 
350 
625 
667 
673 
718 
80 
25 
87.5 
25 
7.5 

85 
25 
92.5 
25 
7.5 



Azzopardi et al. BMC Pediatrics 2008 8:17 doi:10.1186/14712431817 