Fig. 4.

Serum vitamin D [25(OH)D] levels of patients with malignant compared to benign bone tumours grouped according to age (age < 20 years n = 4 for malignant, n = 27 for benign; 20–29 years n = 5 for malignant and n = 26 for benign; 30–39 years n = 7 for malignant and n = 27 for benign; 40–49 years n = 9 for malignant and n = 19 for benign; 50–59 years n = 20 for malignant and n = 23 for benign; 60–69 years n = 17 for malignant and n = 13 for benign; 70 + years n = 21 for malignant and n = 7 for benign).