Assessment of capacity for myoelectric control: a new Rasch-built measure of prosthetic hand control.
OBJECTIVE
To report the results from a Rasch rating scale analysis of the Assessment of Capacity for Myoelectric Control (ACMC) implemented to evaluate internal scale validity, person response validity, separation reliability, targeting and responsiveness of the measures over time.


METHODS
Longitudinal data (18 months) from a prospective study of development of capacity for myoelectric control in children and adults were used for the analysis.


METHODS
A consecutive sample of 75 subjects (43 males, 32 females) with upper limb reduction deficiency or amputation and myoelectric prosthetic hands referred for occupational therapy from September 2000 to March 2002. Participants' ages ranged from 2 to 57 years.


METHODS
Outcome measure was the ACMC. Occupational therapists completed 210 assessments at an arm prosthesis centre in Sweden. A two-faceted rating scale analysis of the data was performed.


RESULTS
All 30 ACMC items and 96.2% of participants demonstrated goodness-of-fit to the rating scale model for the ACMC. Separation and SE values suggested adequate reliability of the item and person estimates.


CONCLUSIONS
The items demonstrated internal scale validity and the participants demonstrated person response validity. The ACMC was well targeted and sensitive enough to detect expected change in ability.
Hermansson
Liselotte M
LM
Limb Deficiency and Arm Prosthesis Centre, Orebro University Hospital, SE-701 85 Orebro, Sweden. liselotte.hermansson@orebroll.se
Fisher
Anne G
AG
Bernspång
Birgitta
B
Eliasson
Ann-Christin
AC
D000203:Activities of Daily Living; D000328:Adult; D000671:Amputation, Surgical / Q000523:psychology / Q000534:rehabilitation; D001132:Arm / Q000002:abnormalities / Q000503:physiopathology* / Q000601:surgery; D001186:Artificial Limbs; D002648:Child; D002675:Child, Preschool; D004576:Electromyography; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009788:Occupational Therapy; D011446:Prospective Studies; D011474:Prosthesis Design; D011594:Psychometrics; D016896:Treatment Outcome