The adaption and evaluation of a Latvian version of the National Institutes of Health Stroke Scale

Objectives To determine the validity and reliability of a Latvian version of the National Institutes of Health Stroke Scale (LV-NIHSS) for evaluating Latvian stroke patients. Methods The adaption of the LV-NIHSS followed standard methods used for the adaption and validation of clinical assessment tools. The scale validity was tested by comparison with the Glasgow Coma Scale (GCS) and the modified Rankin scale (mRs). The reliability of the LV-NIHSS was evaluated by intra-rater and inter-rater agreement using intra-class correlation coefficient (ICC) analysis. Results A total of 296 stroke patients and 101 control subjects were evaluated. The mean age of the overall study population was 73.6 years (range, 37 - 94 years; 227 [57.2%] were female). The mean LV-NIHSS score of the patients with stroke was 8.4 ± 6.2. In terms of construct validity of the LV-NIHSS, it correlated with the GCS ( r = -0.571) and mRs ( r = 0.755). In terms of the reliability of the LV-NIHSS, the inter-rater agreement had an ICC of 0.99 and the intra-rater agreement had an ICC of 0.99. Conclusion The adaption of LV-NIHSS was successful and the evaluation showed that the scale was valid and reliable for evaluating Latvian stroke patients.