#### statistics question - adjustment

S

can someone help to explain this to me --
this sentence "its worth noting that the association between head circumference and 3MS in the current study remained statistically significant after adjustment for IQ"
"after adjustment, head circumference was not statistically significant with all cognitive outcomes"

What does "adjustment" here mean? did they change the values or??

thanks

N

[quote] "its worth noting that the association between head circumference and 3MS in the current study remained statistically significant after adjustment for IQ"
to me, this statement means they statistically controlled for IQ and the association between head circumference and 3MS remained significant.

for example you might an association between two variables, but it was really explained by third variable, or you think it might be, so you control for it and see if the association remains. for example you might find an association between numbers of ice-creams sold and number of drownings, but really there are both explained by hot weather. so if you controlled for the weather (temperature) you find the association between ice-creams sold and drowning is not significant any more.

I dont know what 3MS means in your case, so you will be better able to understand the logic behind your particular case.

"after adjustment, head circumference was not statistically significant with all cognitive outcomes"

In regard to this second statement, I need more information... after adjustment for what?? it means they controlled for something (what?) and the association between head circumference and cognitive outcomes was not significant. if they controlled for IQ this might make sense... high IQ was associated with both larger brains and better cognition...

I feel I understand the stats, but not your topic area... I would be surprised to learn that higher iq was associated with an actual bigger brain...

anyway, hope this helps