The Independent Living Scale (ILS) was developed in a post-acute traumatic
brain injury (TBI) rehabilitation facility over a 15-year period to assess
three main areas: (1) activities of daily living, (2) behaviour, and (3) in
itiation. The purpose of this study was to examine the psychometric propert
ies of the ILS, including test-retest stability, construct validity, and st
atistical fit. Statistical analysis was completed on all weekly scores betw
een the years 1986-1995 (n = 5250). A previous study showed ILS inter-rater
reliability to be 0.85 and convergent validity 0.82-0.87. This study demon
strated a test-retest stability of 0.72, the Kaiser-Meyer-Olkin Measure of
Sampling Adequacy 0.94 (marvelous), and a Bartlett Test of Sphericity resul
t of 'scale items independent'. The ILS was shown to have good construct va
lidity, inter-rater reliability, internal consistency, instrument stability
, and convergent validity.