Table 4. The association between RPR (≥0.043) and disease severity.

Chi-square (χ²) = 41.7, Degrees of freedom (df) = 1

Chi-square p < 0.00000001, Fisher’s exact p = 2 × 10⁻¹⁰

High RPR (≥0.043) is very strongly associated with moderate/severe disease.

RPR group	Mild	Moderate / severe
High (≥0.04)	3	29
Low (<0.043)	23	2