Portuguese translation and validation of the Patient Generated Index (PGI) instrument for patients with Chronic Obstructive Pulmonary Disease: individualized quality of life assessment.

Objective: To translate, adapt and validate the Patient Generated Index (PGI) for Brazilians with chronic obstructive pulmonary disease (COPD). Methods: 50 volunteers with COPD, mostly men (74%), with 73.1 +/- 8.9 years of age, FEV1 of 52.3 +/- 14.5% of predicted and FEV1 / FVC of 56.2 +/- 8.6% of predicted responded to PGI, to the Saint George Respiratory Questionnaire (SGRQ) and to perform Glittre Activities of Daily Living test (Glittre ADL). After 1-2 weeks, PGI was again applied for the analysis of relative and absolute reliability. Results: The translation occurred without changes in the questionnaire. The score obtained in PGI had weak correlation with the SG RO total score (r = -0.44, p <0.001) and with the impact domain (r = -0.40, p <0.05), presented a moderate correlation with the symptoms domain of the SGRQ (r = -0.55, p <0.001) and weak correlation with the activity domain (r = -0.31, p <0.05). A weak correlation was observed between PGI and Glittre ADL (r = -0.30; p <0.05). It was observed high reliability among the measures of PGI (ICCr = 0.94). Conclusion: This study shows that the Brazilian version of PGI is a reliable and valid instrument to measure health-related quality of life (HRQL) in patients with COPD. It is a new and individualized form of evaluation of COPD patient-centered quality of life.