Intraobserver and interobserver reliability of assessments of impairments and disabilities.
OBJECTIVE
The purpose of this study was to evaluate the interobserver and intraobserver reliability of assessments of impairments and disabilities.


METHODS
One physical therapist's assessments were examined for intraobserver reliability. Judgments of two pairs of therapists were used to examine interobserver reliability. Reliability was assessed by Cohen's kappa.


RESULTS
Of the 42 impairments and disabilities assessed by the physical therapist in the intraobserver reliability study, kappa values could be calculated for 33 items. For 31 items (94%), kappa values ranged from .40 to .91, and 2 items (6%) had kappa values of less than .40. To determine interobserver reliability, 37 items were assessed in one practice. Kappa values could be calculated for 34 items, with 30 items (88%) having kappa values ranging from .41 to .80 and 4 items (12%) showing "poor" agreement. In the second practice, 47 items were assessed for interobserver reliability. Kappa values could be calculated for 40 items, with 11 items (27.5%) having kappa values ranging from .41 to .84. Poor agreement was shown for the remaining 29 items (72.5%).


CONCLUSIONS
Assessments of impairments and disabilities are potentially reliable. The differences between practices of the interobserver reliability study can be explained by the fact that one of the therapists did not receive training in the use of the assessment form. More generalizable conclusions will require further study with more subjects and therapists.
Hendriks
E J
EJ
Dutch National Institute of Allied Health Professions, Amersfoort, The Netherlands.
Brandsma
J W
JW
Heerkens
Y F
YF
Oostendorp
R A
RA
Nelson
R M
RM
D000293:Adolescent; D000328:Adult; D004185:Disability Evaluation; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation