Table 5: Sensitivity, specificity, and optimal cut-off values for the chemical intolerance scale and the Life Impact Scale.

Chemical intolerance cut-off scores Sensitivity (%) Specificity (%)  37 95.2 82.8  47 89.3 89.4  58 83.9 95.2 Life Impact Scale cut-off scores Sensitivity Specificity  14 95.8 86.2  21 91.0 90.9  31 86.8 95.2 Combined scale scores Sensitivity Specificity Chemical intolerance cut-off 35/Life Impact Scale cut-off 14 92.1 91.8