Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement

Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.

Using the Patient Generated Index (PGI) To Measure Personalized Quality of Life (QoL) in Patients Undergoing Total Knee Arthroplasty (TKA).

Lopez-Olivo2,  Maria A., Kallen2,  Michael A., Pak2,  Chong H., Siff1,  Sherwin J., Landon1,  Glenn C., Edelstein1,  David, Robinson2,  Kausha C.

St. Luke's Episcopal Health System, Houston, TX
The University of Texas M.D. Anderson Cancer Center, Houston, TX
University of Texas, MD Anderson Cancer Center, Houston, TX


Personalized respondent-generated measures such as the Patient-Generated Index (PGI) can be used as an adjunct to other measures to assess individual quality of life, to improve patients' outcomes through interventions aimed at targeting patients' values for health, and to identify changes in individual responses. The objective of this study was to assess how patients redefine their components of quality of life after a total knee arthroplasty (TKA) during the first six months of recovery.


We interviewed 122 patients with knee osteoarthritis (OA) at baseline, 12 and 24 weeks post TKA. PGI, a semi-quantitative instrument that allows patients to select the areas of their lives that are most affected by their disease, and to rate them using ranking and ordinal scores. The PGI is made up of three stages; each stage is linked to the other stages in sequence: i) the first stage focuses on those areas of life affected by the patients' health; ii) the second stage rates how badly patients are limited by their condition; and iii) the third stage reduce ambiguity in the weighting of life areas by rating the relative importance of potential improvements in the area.


66% of the patients were female; mean age was 65 (8.9) yrs. 63% were married, 70% were White and 25% African American. At baseline, patients were able to select the areas of their lives that were most affected by their knee OA. Patients presented with different combinations problem areas. To reduce the amount of possible combinations, we use the same areas reported at baseline for the 12 and 24 weeks assessments. Five major areas were identified as the most salient: (i) family—this included relationships with family; (ii) physical function—e.g. walking, kneeling, activities of daily living; (iii) health—sleep, fatigue, personal care; (iv) professional life—work and school; and (v) spirituality—church, religious activities. There was a statistically significant difference between observed PGI total scores pre and post TKA: 2.5±1.2 at baseline, 4.2±1.4 at 12 weeks (p<0.001), and 4.3±1.4 at 24-weeks (p=<0.001). Mean score for each area are shown in table 1. Substantial variation was observed in the areas that patients described as affected. Additionally, we observed that the perception of the area that is most affected by the knee OA changed over the time in each patient.

Table 1. Weighted mean PGI scores specific to each domain – 6 months.

 Baseline12 weeks24 weeks24 weeks (fresh)
Physical function36%2.536%4.231%4.152%4.7
Gen health12%2.58%4.211%4.914%4.9
Professional life11%2.27%0.48%4.315%4.2
Other areas5%2.411%4.211%4.32%4.2


Physical function and interference with family life were the most frequent areas identified by patients as detrimental to their QoL. The PGI was responsive to changes in patient's chosen domains for QoL.

To cite this abstract, please use the following information:
Lopez-Olivo, Maria A., Kallen, Michael A., Pak, Chong H., Siff, Sherwin J., Landon, Glenn C., Edelstein, David, et al; Using the Patient Generated Index (PGI) To Measure Personalized Quality of Life (QoL) in Patients Undergoing Total Knee Arthroplasty (TKA). [abstract]. Arthritis Rheum 2010;62 Suppl 10 :178
DOI: 10.1002/art.27947

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