Statement: the primary trial results imply that Zoledronic Acid 4 mg Upfront causes a +ve Change in Bone Mineral Density, whereas Zoledronic Acid 4 mg Delayed causes a smaller, but still positive change in Bone Mineral Density (within a certain patient demographic).
Primary_evidence: Outcome Measurement:    Percentage Change in Bone Mineral Density (BMD) of the Lumbar Spine (L2-L4) at 12 Months of Therapy.   Bone Mineral Density (g/cm^2) of the Lumbar Spine (L2-L4) as measured by energy x-ray absorptiometry (DXA).   Time frame: Baseline, 12 months Results 1:    Arm/Group Title: Zoledronic Acid 4 mg Upfront   Arm/Group Description: Zolendronic acid 4 mg Intravenous (IV) 15 minute infusion every 6 months for 5 years beginning on Day 1. All participants took Letrozole tablets 2.5 mg/day for 5 years beginning on Day 1.   Overall Number of Participants Analyzed: 423   Mean (Standard Deviation)   Unit of Measure: Percentage change in BMD  2.208         (3.4194) Results 2:    Arm/Group Title: Zoledronic Acid 4 mg Delayed   Arm/Group Description: Zolendronic acid 4 mg Intravenous (IV) 15 minute infusion every 6 months beginning when one of the following occurred: BMD T-score <= -2.0 SD at either the lumbar spine or total hip, any clinical fracture unrelated to trauma or an asymptomatic fracture discovered at the Month 36 visit. All participants took Letrozole tablets 2.5 mg/day for 5 years beginning on Day 1.   Overall Number of Participants Analyzed: 418   Mean (Standard Deviation)   Unit of Measure: Percentage change in BMD  -3.617         (4.2151)