Quality of Life Index (QLI, Ferrans & Powers)
The QLI was designed to measure subjective quality of life in terms of satisfaction within different life domains. It originates from Flanagan’s perception of life satisfaction, which holds that two aspects, importance and satisfaction, must be addressed when measuring QOL (Ferrans & Powers 1998). The original QLI is comprised of 4 domains: health and functioning, psychological/spiritual, social and economic, and family.
Number of items: Original (32 items)/ SCI version (37 items)
Procedure/Administration:The QLI can be administered in an interview or by client self-report. The scales (satisfaction and importance) are on a 6-point Likert scale, ranging from 1 (very dissatisfied / very unimportant) to 6 (very satisfied / very important). Five scores are generated (i.e. total and 4 domains) on a 0 - 30 scale.
How scored: Scoring instructions are available on the instrument website (see below).
Interpretability: Importance ratings are used to weight the satisfaction responses, such that scores reflect the respondents’ satisfaction with the aspects of life they value. Items that are rated as more important have a greater impact on scores than those of lesser importance. Scores represent the satisfaction with different aspects of life. Norms are available for the general population, as well as different groups with disabilities.
Acceptability: Psychometric properties for
Time to administer: ~10 minutes
Time to score: N/a
Training required: None.
Availability: The QLI is a copyright instrument that can be used (no charge) in non-profit research or clinical practice and copies can be downloaded from the QLI website http://www.uic.edu/orgs/qli/.
Equipment required: None
The QLI can provide good information to guide interventions on an individual basis. For this purpose, it may be advisable to use the two scales independently in order to establish the precise importance and satisfaction of the specific life domains.
Construct: Green light
Note: TR= Test re-test; IC= Internal Consistency;Inter-O=Inter-observer; Intra-O=Intra-observer; SS=Sensitivity/Specificity; N/a= No information.
Red light= A single study involving SCI subjects which has less than adequate findings of reliability, validity, and/or responsiveness.
Yellow light= A single study involving subjects with SCI which has adequate to excellent findings of reliability, validity, and/or responsiveness.
Green light= At least 2 studies involving subjects with SCI which have adequate to excellent findings of reliability, validity, and/or responsiveness.
- Ferrans C, Powers C. Quality of Life Index; 1998.
- Ferrans C, Powers M. Quality of life index: development and psychometric properties. Adv Nurs Sci 1985;8:15-24.
- Ferrans C, Powers M. Psychometric assessment of the Quality of Life Index. Res Nurs Health 1992;15:29-38.
- May L, Warren S. Measuring quality of life of persons with spinal cord injury: Substantive and structural validation. Qual Life Res 2001;10:503-515.