shanahan,
You can build your own database, here's how.
Again, go to Equibase.
Under Search type in the trainer's name.
On the page that opens scroll to Statistics by Year,
then click 'View' in the year you choose.
All race stats will be displayed. For any claiming races open
where it says 'chart'(like previous post)and if the
horse was claimed return to the page and open the horse's
name. It's displayed just above where it said 'chart'.
You can now check all races after the claim and form your
opinion.
Sounds tedious but it goes quickly.
Good luck.
BH