Table 2. Bone turnover marker, serum calcium, 25-hydroxyvitamin D and PTH level at baseline in the two treatment arms.

	Morning arm	Night arm
Serum CTX (ng ml−1)	0.77 (0.56–0.97)	0.73 (0.54–0.91)
Urinary NTX/creatinine ratio	164.4 (102.2–226.6)	138.7 (85.6–191.8)
Urinary DPD/creatinine ratio	12.8 (10.1–15.6)	11.0 (8.9–13.1)
Serum bone ALP (U l−1)	34.6 (22.7–46.5)	26.3 (21.8–30.8)
Serum osteocalcin (ng ml−1)	11.9 (7.5–16.3)	9.9 (7.8–11.9)
Serum calcium (mg per 100 ml)	10.1 (9.5–10.7)	9.7 (9.4–10.1)
Serum PTH (pg ml−1)	43.1 (25.6–60.7)	50.7 (9.5–91.7)
Serum 25-hydroxyvitamin D (nM)	71.1 (54.9–87.3)	72.4 (56.7–88.0)

ALP=alkaline phosphatase; CTX=C-telopeptide of type-I collagen; DPD=deoxypyridinoline; NTX=N-telopeptide of type-I collagen; PTH=parathyroid hormone.

Data are means (95% confidence interval).