Reliability and Validity of the International Standards for Neurological Classification of Spinal Cord Injury in Patients With Non-traumatic Spinal Cord Lesions
Conditions: Spinal Cord Injuries
Sponsor: I.R.C.C.S. Fondazione Santa Lucia

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RELIABILITY 
AND 
VALIDITY 
OF 
THE 
INTERNATIONAL 
STANDARDS 
FOR 
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NEUROLOGICAL CLASSIFICATION OF SPINAL CORD INJURY IN PATIENTS WITH 
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NON-TRAUMATIC SPINAL CORD LESIONS 
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PROJECT 
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PATIENTS AND METHODS 
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All patients with non-traumatic SCI consecutively admitted to three Italian SCI centers (IRCCS 
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Fondazione Santa Lucia, Montecatone Rehabilitation Hospital and Istituti Clinici Scientifici 
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Maugeri IRCCS of Pavia) between January 1st 2017 and June 30th 2020 have been prospectively 
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enrolled in the study. 
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The study has been registered at Clinicatrials.gov.     
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The study was approved by the ethic committee of IRCCS Fondazione Santa Lucia and all the 
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patients signed an informed consent to the study. 
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Inclusion criteria were: having a non-traumatic SCI in the acute / subacute phase with any level and 
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severity (ASIA Impairment Scale) of injury and having a cognitive status that allows collaboration 
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in the exam. 
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Exclusion criteria were the presence of dementia or cognitive decline; having a pathology of the 
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peripheral nervous system that may affect the evaluation of ISNCSCI; having a multiple sclerosis. 
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The following data were prospectively recorded: 
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- Recording of demographic and clinical history data. Concerning the onset of lesion, for the 
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ischemic and inflammatory groups reference was made to the appearance of the first symptoms, 
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2 
 
while for the neoplastic and spondylogenetic myelopathies we referred to the date of surgical 
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intervention which is usually accompanied by a worsening of the clinical picture. 
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- Evaluation of neurological conditions according to the International Standards For Neurological 
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Classification of Spinal Cord Injury (ISNCSCI) (Revision 2015) (23) with registration of right and 
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left motor and sensory level and of the Neurological Level of Injury (NLI), of the total motor score 
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(MS), of upper extremities (UEMS) and lower extremities (LEMS) motor scores, light touch and 
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pin prick sensory scores, and ASIA Impairment Scale (AIS). This assessment was carried out by 
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two different experienced examiners (Table 1) in each center, 48-72 hours apart. One of the two 
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examiners also assessed the functional status of the patients through the Spinal Cord Independence 
30 
Measure (SCIM) version 2 or 3 (24). 
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- The patients were evaluated at admission with the possibility of repeating the evaluation also 
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during rehabilitation stay and at discharge,. 
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3 
 
Statistics 
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Descriptive statistics: mean and standard deviation (SD) for quantitative data; frequencies and 
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percentages for qualitative ones. Normality of data was assessed by Shapiro-Wilk test. The NLI and 
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the AIS grade have been transformed into numbers and treated as ordinal variables. For the NLI the 
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level C1 corresponds to 1, and the level S4-5 to the number 29. For the AIS grade A correspond to 1 
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and grade E to 5.  
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Validity and reliability represents the main measurement psychometric properties of instruments. 
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The validity of instrument means that it measures what it is intended to measure. (25) while 
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reliability refers to its stability over time (26).  
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Different aspects of reliability were assessed with appropriate tests: correlation (Spearman), test-
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retest reliability (Krippendorf’s Alpha) and internal consistency (Cronbach's Alpha) (27, 28). For 
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motor and sensory scores, we also compared the data of the two examiners by means of Wilcoxon 
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matched pair test to evaluate if there was any significant difference.  
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As to the levels of injury (Neurological Level of Injury, left and right sensory and motor level of 
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injury) and AIS grade the agreement between the two examiners regarding was assessed through the 
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Krippendorff’s Alpha. Furthermore, for the assessment of the levels, we compared the levels 
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established by the two examiners, by counting the difference (1 level, 2 or move levels) in cases 
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where assessments differed.  
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We evaluate psychometric properties of AIS scale on all sample and in each pathology subgroups. 
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As currently there is no gold standard for the neurological evaluation of persons with SCI other than 
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the ISNCSCI, we have evaluated the convergent construct validity of the Standards through a 
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Spearman correlation between the total motor scores, the upper and lower extremities motor scores 
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and the total SCIM score as well as the subscores "Self-care" and "Mobility”. This correlation was 
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performed by means of Spearman test.  
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According to Landis and Koch (29), we interpreted ICC values and the level of agreement by 
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Kappa-values as follows:  
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0–0.1-virtually none 
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0.1–0.4-slight 
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0.41–0.6-fair 
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0.61–0.8-moderate 
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0.81–1-substantial 
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All analyses were performed with SPSS 22. 
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Significance was set at p<0.05 
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Data have been reported according to the Guidelines For Reporting Reliability And Agreement 
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Studies (GRRAS) (supplemental material, Table 15).  
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