Gallagher 2007.

Trial name or title	Vitamin D supplementation in younger women
Methods	Randomised, double‐blind, placebo‐controlled trial using parallel‐group design (five intervention groups)
Participants	Country: United States Estimated number of participants: 200 Inclusion criteria: premenopausal Caucasian or African American women, aged 25 to 45 years (women with hysterectomy and/or oophorectomy must have a premenopausal follicle‐stimulating hormone level); serum 25‐hydroxyvitamin D level 5 to 20 ng/mL; BMI < 45 kg/m2; willing to discontinue vitamin D supplements after entering the trial; negative pregnancy test before BMD and calcium absorption tests; willing to give signed informed consent form Exclusion criteria: cancer (exceptions: basal cell carcinoma or cancer that occurred more than 10 years ago) or terminal illness; previous hip fracture; hemiplegia; uncontrolled type I diabetes ± significant proteinuria or fasting blood sugar > 140 mg in type II diabetes; kidney stones more than two in a lifetime; chronic renal failure (serum creatinine > 1.4 mg/dL); evidence of chronic liver disease, including alcoholism; physical conditions such as severe osteoarthritis, rheumatoid arthritis, heart failure severe enough to prevent reasonable physical activity; previous treatment with bisphosphonates (longer than three months), parathyroid hormone (PTH) or PTH derivatives (e.g. teriparatide or fluoride) in the past six months; previous treatment within the past six months with calcitonin or oestrogen (except birth control pills); long‐term high‐dose corticosteroid therapy (> 10 mg/day) for over six months and not within the past six months; anticonvulsant therapy (Dilantin, phenobarbital); high‐dose thiazide therapy (> 37.5 mg); 24‐hour urine calcium > 290 mg on two baseline tests; serum calcium exceeding upper normal limit on two baseline tests; bone mineral density; T‐score less than ‐3.0 for spine or hip
Interventions	Participants will be randomly assigned to receive: Intervention group 1: vitamin D3 (400 IU) daily; Intervention group 2: vitamin D3 (800 IU) daily; Intervention group 3: vitamin D3 (1600 IU) daily; Intervention group 4: vitamin D3 (2400 IU) daily; or Intervention group 5 (control group): placebo daily for a period of one year
Outcomes	Primary outcome measures will be serum 25‐hydroxyvitamin D and parathyroid hormone. Secondary outcome measures will be serum and urine calcium levels
Starting date	October 2007; Expected completion: January 2012
Contact information	JC Gallagher, MD; tel: 402‐280‐4518; bones@creighton.edu
Notes