The following is an excerpt from Encyclopedia of Gundam Wing Official MS Catalog (Comic BonBon Special 109) which came out in 1997 by Rapport Deluxe. On page 32, there is Trowa's character introduction as well as some ability stats.
TROWA BARTON
Mental Strength 120
Physical Strength 150
Intelligence 150
Infiltration 150
Sensitivity 120
Among the Gundam Pilots he is one of the most taciturn, disliking others prying into his heart and even his name is apparently a pseudonym. On the other hand, he is always searching for a place to return to and people to protect, and it seems that the circus troupe has become that for him. He is light on his feet and has even shown combat prowess that rivals Wufei.