The Quality of Life Index

A Literature Survey of the Usage and Results from the Ferrans and Powers QLI

Ferrans/Powers QLI

•The Ferrans/Powers QLI was created in 1984

•There are Five Scores, including an Overall Score and Four Domains

•There is a General Format as well as 14 Disease Specific Versions

•The QLI has been used in over 200 Published Studies

The Four Domains

•Health and Functionality

•Socioeconomic

•Psychological and Spiritual

•Family

How It Works

•Satisfaction / Importance

•Satisfaction data is centered, giving positive and negative numbers

•Satisfaction is multiplied by Raw Importance

•All numbers added together to produce final results

Level of Pain:

Satis. Imp.2 5

Centering: Satis. Imp.-1.5 5

Multiplication: Satis. Imp. =-1.5 5 -7.5

Cronbach’s Alpha

• A test to compare the sum of a given set of data to the expected sum within a generalized set of data

Alpha Results

•Alpha > .70 is generally considered Reliable

•QLI obtained Alphas from .73 to .99 through 48 studies

Common Sense

•Subjects who self-report Depression generally rank lower on QLI (Ferrans 1990)

•Subjects with Higher Incomes generally rank higher on QLI (Ferrans, Powers 1992)

Correlation

•Short-Form 36 (Another QOL Index)

•Disease Specific Wellness Indices

•e.g. Daytime Sleepiness (Hemodialysis), Jalowiec Coping Scale, 6MW (Pulmonary Rehab)

Consistency

•20 - SD 5 (Pulmonary Rehab)

•21.4 - SD 6.1 (Elderly ICU)

•22.8 - SD 4.0 (Hemodialysis)

•Scores can Easily range +/- 100