Evaluation Of Missed Osteoporosis Diagnoses, And Preference Between Once Monthly Ibandronate And Once Weekly Alendronate

Inclusion Criteria: * Women registered with a GP, without a prior history of osteoporosis. According to a case-finding procedure, osteoporosis will be diagnosed or excluded. Exclusion criteria: * Abnormalities of the esophagus which delay esophageal emptying such as stricture or achalasia. * Inability to stand or sit in the upright position for 60 minutes. * Previous use of bone active agents (e.g. strontium, PTH). * Significant medical condition which may preclude the patient's ability to complete the study. * History of alcohol or drug abuse. * Hypersensitivity to any component of the bisphosphonates alendronate and ibandronate. * Administration of any investigational drug within 30 days preceding the first dose of the study drug. * Serum total calcium \> 10.5 mg/dL or \< 8.0 mg/dL (equivalent to 2.63 mmol/L and 1.99 mmol/L). * Osteoporosis by secondary causes, will be excluded especially when an isolated deformity of the vertebral body is detected during x-ray analysis.