Upper limb use differs among people with varied upper limb impairment levels early post-stroke: a single-site, cross-sectional, observational study.

: There is limited knowledge on the upper limb (UL) use early post-stroke by impairment levels.: To 1) To characterize paretic UL use in people with different UL impairment levels early post-stroke during and outside therapy; 2) compare UL use in people early post-stroke to age-matched controls.: A prospective cross-sectional study of inpatients with first-time stroke ≤4-weeks (n=60, 61±12 years) categorized by Fugl-Meyer UL score for impairment subgroups: mild (51-66), moderate (23-50) and severe (0-22) was conducted. Age-matched, community-dwelling individuals without a history of stroke were recruited (n=30, 60±11 years). Bilateral wrist-worn accelerometers measured the duration of paretic UL use and use the ratio of paretic/non-paretic and non-dominant/dominant UL.: Sixty-three percent of stroke participants with mild impairment used their paretic UL >6 h/day (median (IQR): 6.7(3.3); use ratio 0.9(0.3)). Those with moderate impairment demonstrated wide variation of use; 13.3% achieving >6 h use/day (median (IQR): 4.5(3.8); use ratio 0.5(0.2)). People with severe impairment demonstrated limited use. None achieved >6 h/day of use (median (IQR): 1.7(0.7); use ratio 0.3(0.2)). Paretic UL use and use ratio were greater during therapy compared to outside therapy in moderate and severe groups (<.002). Age-matched controls used their non-dominant UL for 8.7(3.0) hours, significantly more than all stroke participants (<.002).: Patterns of UL use differed by severity of impairment. Moderate and severe groups used their paretic UL more during therapy, inferring that it is possible to increase paretic use despite motor impairment. Future research stratifying by impairment across multinational sites is warranted to generalize findings.