AIM
To examine which instruments used to assess participation of children with acquired brain injury (ABI) or cerebral palsy (CP) align with attendance and/or involvement constructs of participation; and to systematically review measurement properties of these instruments in children with ABI or CP, to guide instrument selection.

METHOD
Five databases were searched. Instruments that quantified ‘attendance’ and/or ‘involvement’ aspects of participation according to the family of participation-related constructs were selected. Data on measurement properties were extracted and methodological quality of the studies assessed.

RESULTS
Thirty-seven instruments were used to assess participation in children with ABI or CP. Of those, 12 measured attendance and/or involvement. The reliability, validity, and responsiveness of eight of these instruments were examined in 14 studies with children with ABI or CP. Sufficient measurement properties were reported for most of the measures, but no instrument had been assessed on all relevant properties. Moreover, most psychometric studies have marked methodological limitations.

INTERPRETATION
Instruments to assess participation of children with ABI or CP should be selected carefully, as many available measures do not align with attendance and/or involvement. Evidence for measurement properties is limited, mainly caused by low methodological study quality. Future studies should follow recommended methodological guidelines.