I believe the current medium - large size SUV crach test winner is the Highlander for 2002 but I think it will change for 2003.
The Highlander hasn't been tested by NHTSA yet, but it has been tested by IIHS. It did well, but some other SUV's did better.
In the Insurance Institute of Highway Safety crash test, the highest-scoring small SUV to date is the Honda CR-V, with the Subaru Forester in second place:
In their tests of mid-sized SUV's, the highest ranking vehicle is the BMW X5, with the MDX second:
The Highlander weighs significantly less than some of the other SUV's that scored higher than it. That likely means that the Highlander would do worse than than those other vehicles in a collision with, say, a heavier 4,800 lb vehicle.
IIHS runs an offset crash test, which is more demanding on the vehicle's structure The government (NHTSA) runs a full-frontal crash test, which places more emphasis on the restraints. NHTSA also runs a side-impact crash test. Both the Pilot and MDX are expected to get 5 stars in the NHTSA's tests.
Here are NHTSA results for mid-sized SUV's tested (2002 model year):