Table 2: Median scores and scale reliability coefficients (Cronbach’s alpha).

Scale group 𝑁 Symptom scaleChemical intolerance scaleOther intolerance scaleLife Impact scale
Median (IQR)**Alpha***Median (IQR)AlphaMedian (IQR)AlphaMedian (IQR)Alpha

Patient sample18947 (30–64)0.8480 (62–91)0.9134 (20–53)0.8364 (45–80)0.89
Population130911 (5–23)0.8613 (4–30)0.9210 (3–19)0.772 (0–8)0.86

Population*
 −3020112 (5–23)0.8311 (4–24)0.8711 (3–19)0.644 (0–10)0.74
 30–4021811 (4–21)0.8515 (5–31)0.9311 (5–22)0.792 (0–8)0.86
 40–5028811 (6–22)0.8914 (5–30)0.9211 (5–18)0.792 (0–8)0.90
 50–6031212 (5–23)0.8614 (4–32)0.948 (3–17)0.781 (0–9)0.87
 60−29010 (4–23)0.8612 (1–29)0.935 (0–17)0.750 (0–5)0.81

*Population sample grouped by age.
**Interquartile range.
***Cronbach’s alpha.