Self- and proxy-report agreement on the Stroke Impact Scale.
OBJECTIVE
The purpose of this study was to examine proxy-patient agreement on the domains of the Stroke Impact Scale (SIS), as per the proxy-proxy perspective.


METHODS
Stroke patients were prospectively assessed by means of the NIH Stroke Scale, Barthel index, and modified Rankin scale. Proxies and patients answered the Hospital Anxiety and Depression Scale and the SIS 3.0. Comparisons of patient-proxy mean scores (paired t test), effect size, and intraclass correlation coefficients (ICC) were calculated for each of the SIS domains, and weighted kappa for individual items.


RESULTS
180 proxy-patient pairs were assessed. Proxies were younger (mean age: 43.1 versus 57.9 years) and had a higher education level (P<0.0001). The bias between patient-proxy mean differences was low (from 5.3, Strength, to 0.1, Communication). Proxies significantly scored patients as more severely affected in Strength (41.7 versus 36.6; P<0.0001) and ADL (46.2 versus 43.1; P=0.01) domains, and Composite Physical Domain (CPD; 39.7 versus 34.9; P<0.0001). The magnitude of difference was small (size effect: 0.21). ICC values for the SIS domains ranged from 0.17 (Emotion) to 0.79 (Hand function). The ICC value for the CPD was 0.83. Memory, Communication, Emotion, and Social Participation domains had ICC lower values. The weighted kappa values for the SIS items ranged from 0.09 (item 4e) to 0.80 (item 7d). Highest values (moderate/high agreement) were observed for the SIS-16 and CPD (kappa values: 0.31 to 0.80).


CONCLUSIONS
Agreement between stroke patients and proxies was acceptable for most SIS domains and SIS-16. Proxy's assessment of SIS subjective domains should be taken with caution.
Carod-Artal
Francisco Javier
FJ
Neurology Department, Sarah Hospital, Brasilia DF, Brazil. fjcarod-artal@hotmail.com
Ferreira Coral
Luciane
L
Stieven Trizotto
Daniele
D
Menezes Moreira
Clarissa
C
D000203:Activities of Daily Living; D000328:Adult; D000339:Affect; D001008:Anxiety Disorders / Q000175:diagnosis* / Q000453:epidemiology; D001294:Attitude to Health; D017028:Caregivers / Q000523:psychology; D003142:Communication; D003866:Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology; D004185:Disability Evaluation; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D015588:Observer Variation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019727:Proxy / Q000523:psychology*; D011594:Psychometrics / Q000379:methods; D011788:Quality of Life; D015203:Reproducibility of Results; D012647:Self-Assessment; D012720:Severity of Illness Index; D020521:Stroke / Q000453:epidemiology / Q000523:psychology*