The Berlin Bimanual Test for Tetraplegia (BeBiTT): development, psychometric properties, and sensitivity to change in assistive hand exoskeleton application.

Only 14 people were tested at baseline, and 10 used the exoskeleton, so the result is from a small sample. Four participants could not use the exoskeleton because of fit, pain, surgery risk, or skepticism, so the intervention result does not apply to everyone with tetraplegia. The baseline test was done before the exoskeleton test, and there was no control for sequence or fatigue, so learning could have helped the intervention scores. The exoskeleton was worn on one hand only, so this does not show what a two-hand system would do. The participants were limited to cervical injuries C4 to C6 and ASIA grades A to C, so it is unclear how the test performs in other injury levels or severities. Some daily-life categories have only one test item to keep the test short, so the test may not cover all bimanual activities equally. The authors say larger studies are needed before broad clinical acceptance.

Funders named include European Research Council, Bundesministerium für Bildung und Forschung, ERA-NET Neuron, Ministry of Education, Science and Technology, Einstein Stiftung Berlin, and Charité - Universitätsmedizin Berlin (3093). The supplied text does not include an author conflict-of-interest declaration.

Do not conclude that a brain-controlled exoskeleton improves all bimanual hand function. Total scores improved on average, but manipulation did not improve significantly, and the baseline was tested first, so learning effects may have contributed.