How long will it take to drive to Columbia Presbyterian Medical Center
(168th Street and Fort Washington Ave in Manhattan) from the following
places in Queens if I need to be there between 7:30-8am? Where would I
encounter the most trafic (Grand Central? Triboro? Harlem River
drive?) Assume that I don't want to go through the Bronx and take the
Cross Bronx Expressway.

a) Forest Hills
b) Little Neck
c) Bayside
d) Douglaston 

Actual experience (i.e. someone who actually makes the drive) would be
much more helpful than a list of websites that have traffic
information.

Thank you.

What about putting the question on the center's bulletin board,
electronic or otherwise?  Maybe someone there drives the route.

the best way is GCP to triborogh bridge, then up harlem river drive,
going towred GW bridge, take the last exit ( 181 st) exit then go
south on river side drive , you are at the hospital. if you leave home
by 7.00 am you should be at the hospital before 8.00am. from any of
the 4 locations in queens. i know it i drive for living