The two most common would be above tab no 7 or tab no 5 and above and placed last start also broken into 1,2 or 1,2 3 combos or 1,2,3 ,4 last start

or beaten lengths last start 2 l under 1600 and 3l a 1600 and above ???

To let the tab no, sort class, bit rough but seems to work and try to see if the horse is in form rough again but not with out merit.