The Neurological Impairment Scale: reliability and validity as a predictor of functional outcome in neurorehabilitation

Abstract

PurposeTo examine the construct validity and inter-rater reliability of the Neurological Impairment Scale (NIS) and compare ratings by medical and multidisciplinary teams in a mixed neurorehabilitation sample. To assess its concurrent and predictive validity as a predictor of outcome and functional gains during inpatient rehabilitation.MethodsThe NIS was rated in a consecutive cohort of patients (n = 428) recruited from nine specialist neurorehabilitation units in London. Dimensionality and internal consistency were explored through principal components analysis with Varimax rotation. Inter-rater reliability and the relationship between NIS and functional outcome (UK Functional Assessment Measure (FIM + FAM)) were analysed in a sub-sample (n = 94) from one centre.ResultsFactor analysis identified two principal domains (“Physical” and “Cognitive”) together accounting for 35% of the variance: their Cronbach’s alpha values were 0.76 and 0.67, respectively. Inter-rater reliability was excellent for overall scores between doctors (ICC = 0.95 (95% CI = 0.91–0.97)) and acceptable between the medical and multidisciplinary team (ICC = 0.92 (95% CI = 0.88–0.95)). Change in NIS-physical score predicted 29% of the variance in functional gain (FIM + FAM change).ConclusionThese findings provide the first formal evidence for the validity and reliability of the NIS as a measure of neurological impairment for use in general neuro-rehabilitation settings. Its further application and exploration are now warranted.Implications for RehabilitationThe extent of neurological recovery occurring during rehabilitation can make an important contribution to functional gains. In order to interpret measurement of functional outcome, we need to be able to identify changes at the level of impairment.Many of the available tools to measure severity of impairment are condition specific. The Neurological Impairment Scale (NIS) was developed for use across a broad range of disabling conditions alongside the UK FIM+FAM.This first formal examination of its psychometric properties provides evidence for its scalability, reliability and validity.The NIS has potential to provide useful information for case-mix adjustment and as a predictor of functional gain in general neurorehabilitation settings.

An enriched environmental programme during inpatient neuro-rehabilitation: A randomized controlled trial

“…The secondary outcomes included: • Impairment: the Neurological Impairment Scale (NIS-version 8) (27), comprises 17 items (each rated 0-2 or 0-3, giving a total score range 0-50), to assess neurological impairments. It recorded severity of functional impairments across 13 domains mapped onto the ICF.…”

A longitudinal, multicentre, cohort study of community rehabilitation service delivery in long-term neurological conditions

“…The NIS comprises a brief 17-item checklist of the major neurological impairments (motor/sensory loss, cognitive, communication, emotional, behaviour) that make up a complex presentation in people with LTNCs 19. Item severity scores range from 0 to 3 to assess the impact of these impairments at a functional level, giving a total score range 0–50.…”

“…Item severity scores range from 0 to 3 to assess the impact of these impairments at a functional level, giving a total score range 0–50. Originally developed as part of the core minimum dataset alongside the UK Functional Assessment Measure,26 the NIS is shown to be a valid and reliable measure of neurological impairment suitable for use across a wide range of neurological conditions 19. It forms a part of the UK Rehabilitation Outcomes Collaborative (UKROC) national clinical dataset for specialist rehabilitation services (for further information see http://www.csi.kcl.ac.uk/ukroc.html; accessed 9 January 2014).…”

Pediatric survivors of out-of-hospital ventricular fibrillation: Etiologies and outcomes

“…After resuscitation, the patient's neurologic status was evaluated using the standardized Neurologic Impairment Scale, which provides a basic assessment of both cognitive and physical function. 7 A score of 0 indicates normal function; 1 implies mild impairment, affecting high-level function only; 2 implies moderate impairment, with significant impairment but useful function; and 3 implies severe impairment of either cognitive or physical function, with limited rehabilitative potential. Patients who did not survive to hospital discharge were not included in this portion of the analysis.…”

“…Based on prior known diagnoses as well as subsequent evaluation after admission, the following diagnostic categories were determined: primary electrical disease (15), cardiomyopathy (12), congenital heart defect (5), other (6), and unknown (7). Two patients, initially discharged with an unknown cause of OOH-VF, were subsequently determined to have catecholaminergic polymorphic ventricular tachycardia based on clinical phenotype in 1 and genetic testing in the second, which demonstrated compound pathogenic heterozygous triadin mutations.…”