The 66-item Quality of Life Index (QLI)[46] measured participants’ self-rated quality of
life by assessing their satisfaction with and the importance of 33 life areas in four domains:
health and functioning, psychological/spiritual, social and economic, and family. Scale items
were rated on a 6-point Likert-type scale. The satisfaction scale ranged from 1 ‘very
dissatisfied’ to 6 ‘very satisfied’ and the importance scale ranges from 1 ‘very unimportant’
to 6 ‘very important.’ The satisfaction ratings were weighted by the importance ratings to
yield a total quality of life score and a score for each domain. The QLI has high internal
consistency across healthy and ill groups (Cronbach alpha of .93 and.90, respectively) and
strong test-retest correlations (.81 over 2 weeks and .87 over 1 month) [46]. The scale has
been widely used in the general population and among people with various chronic illnesses,
including mobility-limiting disorders such as spinal cord injury, multiple sclerosis, and
stroke, and has been found to have strong psychometric properties [47–49], including
sensitivity to change [50–52].
The 42-item Inventory of Felt Energy and Emotion in Life (I FEEL) assessed general
positive and negative affect[53]. The I-FEEL referenced the last two weeks, and asked
participants to rate how they felt on 42 single-words (e.g., ‘happy’) or short phrases (‘like no
one likes me’) using a 7-point Likert-type scale ranging from 1 ‘not at all’ to 7 ‘all the time.’
The I FEEL assessed feelings of loneliness, negative self-evaluation, somatic complaints,
lack of energy, and various anxiety dimensions (hostile anxiety, fearful anxiety, and nervous
anxiety). The I FEEL also assessed positive affective states such as feelings of social
connectedness, active energy, calmness, and positive self-evaluation. Each dimension has
demonstrated high levels of internal consistency (Cronbach alpha of .83–.95 with a median
of .91). The dimensions also have demonstrated high-levels of concurrent and predictive
validity [54].
Participant self-reports of engaging in moderate and vigorous physical activity were
obtained using several physical activity questions from the Behavioral Risk Factor
Surveillance Survey [55, 56]. Participants reported whether they engaged in moderate and
vigorous physical activity and how many days per week and minutes per day they did so.
The scale allowed for calculating the total weekly minutes spent in moderate and vigorous
activity.