Development and validation of a remote NIH stroke scale (rNIHSS) for caregiver-assisted telestroke assessments

Objectives

NIH stroke scale (NIHSS) assessment is crucial in Telestroke. However, certain NIHSS items demonstrated poor reliability when assessed remotely. We aimed to develop a modified remote version of the NIHSS (rNIHSS) for caregiver-assisted telestroke assessments.

Materials and methods

We evaluated 102 stroke patients. A neurologist conducted the NIHSS assessment remotely via smartphone, assisted by caregivers, and followed by bedside evaluation by another neurologist. The agreement for total NIHSS scores and each individual item was tested. The rNIHSS was developed by excluding unreliable items, followed by evaluation of its reliability and validity.

Results

Caregiver-assisted remote NIHSS assessments demonstrated limited reliability (84.3 % agreement). The rNIHSS was developed by excluding items with poor wK values: visual field, facial palsy, extinction/inattention, and ataxia. Remote rNIHSS assessments in mild stroke cases were equivalent to bedside assessments, with 98.2 % of the subjects having total scores that differed by ≤ 2 points; however, the reliability was limited in moderate and severe strokes (93.1 % and 77.8 % agreement, respectively). The correlation coefficients for the rNIHSS scores and bedside NIHSS scores, and the 90-day and 1-year modified Rankin scale scores were 0.97, 0.88, and 0.86, respectively (p < 0.01).

Conclusions

Caregiver-assisted rNIHSS remote assessment improved reliability in mild stroke patients but was limited in severe cases. Prospective validation of the rNIHSS is needed.