Rasch Analysis of the Fullerton Advanced Balance (FAB) Scale.
OBJECTIVE
This cross-sectional study explores the psychometric properties and dimensionality of the Fullerton Advanced Balance (FAB) Scale, a multi-item balance test for higher-functioning older adults.


METHODS
Participants (n=480) were community-dwelling adults able to ambulate independently. Data gathering consisted of survey and balance performance assessment. Psychometric properties were assessed using Rasch analysis.


RESULTS
Mean age of participants was 76.4 (SD=7.1) years. Mean FAB Scale scores were 24.7/40 (SD=7.5). Analyses for scale dimensionality showed that 9 of the 10 items fit a unidimensional measure of balance. Item 10 (Reactive Postural Control) did not fit the model. The reliability of the scale to separate persons was 0.81 out of 1.00; the reliability of the scale to separate items in terms of their difficulty was 0.99 out of 1.00. Cronbach's alpha for a 10-item model was 0.805. Items of differing difficulties formed a useful ordinal hierarchy for scaling patterns of expected balance ability scoring for a normative population.


CONCLUSIONS
The FAB Scale appears to be a reliable and valid tool to assess balance function in higher-functioning older adults. The test was found to discriminate among participants of varying balance abilities. Further exploration of concurrent validity of Rasch-generated expected item scoring patterns should be undertaken to determine the test's diagnostic and prescriptive utility.
Penelope J. Klein, PT, EdD:  Faculty researcher and professor, Department of Physical Therapy, D'Youville College, Buffalo, New York.
Penelope J
PJ
Klein
Roger C
RC
Fiedler
Debra J
DJ
Rose
D003430:Cross-Sectional Studies; D006801:Humans; D004856:Postural Balance; D011594:Psychometrics; D012046:Rehabilitation; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires