Interest in a quantifiable global rating of functioning date back to as early as 1962 with the publication of the Health-Sickness Rating Scale (which was rated 0 to 100) by Luborsky et al. in the paper "Clinicians' Judgements of Mental Health".
The related SOFAS (Social and Occupational Functioning Assessment Scale) scale was initially described in a paper by Goldman et al. in 1992 in the paper "Revising Axis V for DSM-IV: A review of measures of social functioning."