Based on the available evidence , motor evoked potentials at rest were the only biomarker that predicted motor outcome in individuals with severe arm impairment following stroke .
To build an underst and ing of the neurobiology underpinning arm recovery in people with severe arm impairment due to stroke , we conducted a pooled individual data systematic review to : 1 ) characterize brain biomarkers ; 2 ) determine relationship(s ) between biomarkers and motor outcome ; and 3 ) establish relationship(s ) between biomarkers and motor recovery .
The PREP algorithm predicts potential for upper limb recovery after stroke.
Stroke is a leading cause of adult disability and the recovery of motor function is important for independence in activities of daily living . Predicting motor recovery after stroke in individual patients is difficult . Accurate prognosis would enable realistic rehabilitation goal - setting and more efficient allocation of re sources . The aim of this study was to test and refine an algorithm for predicting the potential for recovery of upper limb function after stroke . Forty participants were prospect ively enrolled within 3 days of ischaemic stroke . First ,  shoulder abduction and finger extension strength  were grade d 72 h after stroke onset to compute a shoulder abduction and finger extension score . Secondly , transcranial magnetic stimulation was used to assess the functional integrity of descending motor pathways to the affected upper limb . Third , diffusion-weighted magnetic resonance imaging was used to assess the structural integrity of the posterior limbs of the internal capsules . Finally , these measures were combined in the PREP algorithm for predicting an individual 's potential for upper limb recovery at 12 weeks , measured with the Action Research Arm Test . A cluster analysis was used to independently group patients according to Action Research Arm Test score at 12 weeks , for comparison with predictions from the PREP algorithm . There was excellent correspondence between the cluster analysis of Action Research Arm Test score at 12 weeks and predictions made with the PREP algorithm . The algorithm had positive predictive power of 88 % , negative predictive power of 83 % , specificity of 88 % and sensitivity of 73 % . This study provides preliminary data in support of the PREP algorithm for the prognosis of upper limb recovery in individual patients .  PREP may enable tailored planning of rehabilitation and more accurate stratification of patients in clinical trials
Based on the available evidence , motor evoked potentials at rest were the only biomarker that predicted motor outcome in individuals with severe arm impairment following stroke .
To build an underst and ing of the neurobiology underpinning arm recovery in people with severe arm impairment due to stroke , we conducted a pooled individual data systematic review to : 1 ) characterize brain biomarkers ; 2 ) determine relationship(s ) between biomarkers and motor outcome ; and 3 ) establish relationship(s ) between biomarkers and motor recovery .