The Diagnostic Value of Neuropathy Symptom and Change Score, Neuropathy Impairment Score and Michigan Neuropathy Screening Instrument for Diabetic Peripheral Neuropathy

<b><i>Aims:</i></b> This study aims to evaluate the diagnostic capabilities of neuropathy symptom and change (NSC) score, neuropathy impairment score (NIS) and Michigan neuropathy screening instrument (MNSI) in diagnosing diabetic peripheral neuropathy (DPN). <b><i>Methods:</i></b> A total of 131 patients with type II diabetes received NSC, NIS and MNSI scoring systems. Electromyography/nerve conduction velocity (EMG/NCV) test was taken as gold standard. Correlations between EMG/NCV test and the 3 scorings, and their sensitivity, specificity, positive and negative predictive values, accuracy and kappa (&#954;) value were analyzed. <b><i>Results:</i></b> The prevalence of DPN was 43.5% according to EMG/NCV findings. EMG/NCV test was significantly positive correlated with all the 3 scorings, highest with NIS scoring (r = 0.653, p < 0.001). Compared with EMG/NCV test, NSC score was most sensitive (85.96%) but least specific (77.03%); NIS score had lower sensitivity (59.65%) but best specificity (98.65%) and accuracy (81.68%). Both had high concordance with EMG/NCV test (&#954; = 0.61). Sensitivity, specificity and accuracy of MNSI were highest (70.18, 98.65 and 80.15%) at the cutoff values of >1.0, >2.5 and >1.5, respectively (&#954; = 0.58). <b><i>Conclusions:</i></b> Both NSC and NIS were accurate and reliable diagnostic methods for DPN. The combined application of NSC and NIS was recommended in DPN diagnosis.