CNC Properties

Independent interrater reliability calculated at three time periods was calculated at 0.97. Interrater intercorrelations were quite high, with the lowest correlation being 0.86 (item 8, nasal swab). Inter-item correlations were obtained including the alpha coefficient. Alpha coefficients were 0.43, 0.65, and 0.65 for CNC scores done at 1, 8, and 16 weeks post injury (Rappaport, 1992).

A rank order correlation between CNC and DRS scores was 0.69 (p<.02). The correlation between CNC and the degree of abnormality of the multisensory (auditory, visual, and somatosensory) evoked potential patterns (MEPA- Mean Evoked Potential Abnormality) was 0.52 (p<.05) (Rappaport, 1992).