Condition or Disorder Intervention vs. Control Outcome Follow-up Duration Event Rates % NNT (95% CI)
CER EER
Nonvertebral fractures in community living elderly persons1 Calcium and Vitamin D Supplementation vs.placebo Nonvertebral fractures 3 years 13 6 15 (8 to 12)
Nonvertebral fractures and bone loss2 Calcium and vitamin D vs.placebo Nonvertebral fractures 3 years 13 6 15 (8 to 12)
Alzheimer disease3 Donepezil vs.placebo Nausea 12 weeks 8 22 8 (5 to 17)
Insomnia 5 18 9 (6 to 18)
Diarrhea 3 13 10 (6 to 20)
Non-vertebral fractures and bone loss in the elderly4 Elemental calcium+vitamin D vs. placebo Non-vertebral fractures verified by radiographs or hospital records 3 years 12.9 5.9 15 (8 to 12)
Hip fractures in nursing home patients55 External hip protectors vs. control(no hip protector) Hip fracture 1 month 7.4 3.2 24 (13 to 183)
New fractures in postmenopausal women who had low bone-mineral density and existing vertebral fractures6 Alendronate sodium vs. placebo New vertebral fractures confirmed by radiography 3 years < 75 years of age: 13 < 75 years of age: 6 < 75 years of age: 15 (11 to 27)
≥75 years of age: 18 ≥75 years of age: 11 ≥75 years of age: 15 (8 to 21)
Postmenopausal77 Alendronate sodium vs. placebo ≥1 day of bed rest 3 years 15 11 23 (15 to 56)
≥7 days of bed rest 9 4 21 (17 to 32)
≥7 days of limited activity 44 41 23 (12 to 308)
Postmenopausal women with osteoporosis8 Oral risedronate vs. placebo New vertebral fractures 3 years 16 11 20 (11 to 111)
Non-vertebral fractures 8 5 32 (17 to 250)
Residents in nursing homes9 Pharmacist medication review vs. no review Deaths from 5 to 8 months (intervention phase) 8 months 9 4 17 (9 to 213)
Hip fracture patients with mild to moderate dementia10 Intensive geriatric rehabilitation (advice, training, drug treatment, physiotherapy, occupational and speech therapy) vs. control group (discharge to a local hospital) Independent living at 3 months-mild dementia 1 year 67 91 5 (3 to 16)
Independent living at 3 months -moderate dementia 1 year 17 63 3 (2 to 9)
Vertebral fractures in men with osteoporosis11 Alendronate vs. placebo Incidence of vertebral fractures 2 years 7 1 16 (7 to 56)

  1. N Engl J Med 1997; 337:670-6 
  2. N Engl J Med 1997 Sep 4;337(10):670-6 
  3. Arch Intern Med 1998 May 11;158(9):1021-31 
  4. N Engl J Med. 4 Sept 1997; 337: 670-6 
  5. Lancet. 2 Jan 1993; 341: 11-3 
  6. Arch Intern Med. 8/22 Dec 1997; 157: 2617-24 
  7. Arch Intern Med. Jan 10, 2000; 160: 77-85 
  8. JAMA. Oct 13, 1999; 282: 1344-52 
  9. Br J Psychiatry. Jun 2000; 176: 563-7 
  10. BMJ. Nov 4, 2000; 321: 1107-11 
  11. N Engl J Med. Aug 31 2000: 343: 604-10