Table 2

 Comparison of findings among patients with NF1 with different estimated numbers of dermal neurofibromas

Number of external neurofibromas
*Serum 25-hydroxyvitamin D concentration.
10–99100–999⩾1000
Number of patients16247
Age in years (mean (SD))37.2 (10.7)43.2 (7.5)50.4 (7.8)
Statistical significanceF2,44 = 5.7, p = 0.006
Vitamin D* (ng/mL)
    Geometric mean (SD)19.5 (1.4)13.1 (1.5)8.2 (1.6)
    Statistical significanceF2,44 = 12.7, p<0.0001 (unadjusted)
F2,43 = 9.7, p = 0.0003 (adjusted for age)
    Proportion <20 ng/mL9/16 (56%)20/24 (83%)6/7 (86%)