The<unk>  (SSI), of a bone, is a surrogate measure of bone strength determined from a cross-sectional scan by QCT or pQCT (radiological scan). The<unk>  is used to compare the structural parameters determined by analysis of QCT/pQCT cross-sectional scans to the results of three point bending test. __TOC__
Stress–strain index
Extraction ratio
Ejection fraction
Coronary flow reserve
Pressure reactivity index
Instantaneous wave-free ratio
E/A ratio
Oxygen enhancement ratio