The initial lumbar spine and femoral neck BMD assessment and the determination of the patient's eligibility for entry into the screening phase will be made by the central quality assurance for BMD. The central quality assurance center will determine the patient's eligibility for enrollment into the treatment phase. If the L-1 vertebra cannot be analyzed due to artifacts, vertebral fracture, osteophytes, or other abnormalities, that vertebra should be excluded from the analysis.