We use the concept of OLD - Operational Landing Distance, it's the new 'thing' apparently!
It's the ALD (Advisory Landing Distance) found in the PI section of the old QRH but has a 15% factor added to cater for us not all being test pilots. This factor sometimes increases to 30% if the conditions dictate (low temp/dewpoint split).
All of this background is in our company manuals.
Hope it helps.
B&S