Accidental Falls--prevention & control Activities of Daily Living Age Factors Aged Aged, 80 and over Bone Density--physiology Confidence Intervals Cross-Sectional Studies Fear Female Fractures, Spontaneous--diagnostic imaging Geriatric Assessment Humans Multivariate Analysis Odds Ratio Osteoporosis, Postmenopausal--complications Pain Measurement Postural Balance Quality of Life Radiography Risk Assessment Severity of Illness Index Spinal Fractures--diagnostic imaging