The smaller the Recovery Multiplier, the better.
On page 145, you can find the Healing Recovery Table, which is used to determine how long it takes a character to heal naturally from a given wound (this is based on the severity of the wound and the character's Con bonus, etc..)
This can generate recovery times from 1-100 days for a given injury. The racial mods would then adjust these times.
For example, say you have a Con bonus of 5, and a Recover Multiplier of 0.5 and you take a Severe injury (Organ damage). Rolling on the table on page 145, you roll low, a 23 for a total of 28, resulting 6 x 10 (Severe) days to heal the injury. Your Racial multiplier is then applied --> 60 x 0.5 = 30 days to heal the Organ damage.