COLOMETRIC ANALYSIS

[The Big Guy]

Regarding :colormetric chemical analysis. 

What exactly is the difference between  how specific and/or sensitive a method 
is?
My understanding is a specific test will only detect a specific say chemical due to 
a specific color endpoint. A sensitive test  can be specific for that chemical but 
also sensitive or give similar results for other substances that react in the same 
way as the chemical the test is specific for.
For example: Is the colormetric analysis of phenolphthalein by alkalination with 
NaOH specific only for phenolphthalein? Even though it is sensitive for 
phenolphthalein's reaction of turning pink-red when alkalined with NaOH ,is it 
still specific for phenolphalein if it is sensitive in the fact that other substances 
can react with NaOH and the resulting color is very simliar to phenolphthalein's 
endpoint?  

Thanks for the help ahead of time!
Slightly confused,
Patty