About ACMC
The “Assessment of Capacity for Myoelectric Control” (ACMC) is an observational assessment developed to assess the ability of a prosthesis user to control a myoelectric prosthetic hand. During the administration of ACMC, the rater observes a myoelectric prosthetic user performing a daily bimanual activity, then rates the user’s capability to control the prosthesis on 22 items in 4 different areas: gripping, holding, releasing and re-adjusting the grip. During the assessment, the person is encouraged to perform the tasks using the prosthetic hand as actively as possible to enable assessment of the capability to operate the prosthetic hand.
Each item in the ACMC is an observable prosthetic hand movement, such as timing during grasping, or an observable prosthetic hand movement in relation to other body parts, such as uses the prosthesis in different positions away from the body.
The ACMC assesses how skillful a prosthesis hand user performs different prosthetic hand movements when performing a bimanual activity and therefore an ACMC assessment is carried out during the client’s performance of an everyday activity, live or video recorded. The activity is often selected according to the development and interest of the user and hence, the assessment is suitable for users of different ages, either prosthetic side and different prosthetic levels. Suggestions for activities have been developed for use during ACMC assessments.
The original ACMC (version 1.0, year 2004) consists of 30 items. The results from different Rasch analyses led to item combination, clarification of item definitions, and rating category redefinitions. Consequently, the current ACMC (version 3.2, year 2025) consists of 22 items, a redefined rating scale and the ACMC units are reported in a range of 0-100. Each person’s performance is rated on a 4-point capability scale:
0 – Not capable
1 – Somewhat capable
2 – Generally capable
3 – Extremely capable
More detailed information about scoring is available for certified ACMC raters.