ASSESSING QUALITY-OF-LIFE AFTER STROKE - THE VALUE AND LIMITATIONS OFPROXY RATINGS

Background and Purpose Because many stroke survivors have cognitive an d communication disorders, self-reported information on a patient's qu ality of life (QL) cannot always be obtained. Proxy ratings may be use d to prevent exclusion of this highly relevant subgroup of patients fr om QL studies. The purpose of this study was to evaluate both the valu e and possible limitations of such proxy ratings. Methods The patient sample was composed of 437 patients who had suffered a stroke 6 months earlier. QL was assessed by means of the Sickness Impact Profile (SIP ). For 108 patients who were not communicative because of cognitive or linguistic deficits, proxy ratings on the SIP were provided by the pa tients' significant others. For 228 of the 329 communicative patients, both self-reported and proxy SIP ratings were obtained. Results When mean SIP scores for patients with both self-reported and proxy-derived data available were compared, the proxy mean scores were generally in close agreement with those of the patients. However, systematic diffe rences were noted for several SIP scales, with proxies rating patients as having more QL impairments than the patients themselves. Intraclas s correlations were moderate to high for most SIP subscales (average i ntraclass correlation coefficient [ICC]=.63), the physical (ICC=.85) a nd psychosocial dimensions (ICC=.61), and the total SIP score (ICC=.77 ). The proxy SIP scores were sensitive to differences in patients' fun ctional health, which supports the validity of these ratings. For all patients combined, more QL impairments were found for patients with su pratentorial cortical or subcortical infarctions and hemorrhages than for patients with lacunar infarctions and infratentorial strokes. Alth ough proxy respondents were more frequently needed for patients with t he first two types of stroke, we found no evidence of biased results a s a consequence of an unbalanced use of proxy respondents across the d ifferent types of stroke. Conclusions These results suggest that the b enefits of using proxy ratings for noncommunicative patients outweigh their limitations. The findings stress the need for inclusion of this important subgroup of patients in QL studies. Their significant others are able to provide useful information on these patients' QL.