This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Zometa on Bone Mineral Density in Prostate Cancer Patients Undergoing Androgen Ablation Therapy (NCT00582556), a randomized phase 2 study. The primary outcome is The Number of Subjects Who Had Either an Increase or Decrease on Bone Mineral Density of the Lumbar Spine and Femoral Neck in Men Undergoing Androgen Deprivation Therapy for Prostate Adenocarcinoma..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00582556 |
| Phase | Phase 2 |
| Condition | Prostate Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 44 |
| Arms in the primary outcome | 3 |
| Lead sponsor | University of Wisconsin, Madison |
| Results posted | Yes |
2. Clinical Question
Population
The trial enrolled men with stage D prostate cancer undergoing androgen deprivation therapy. The registry lists Prostate Cancer as the condition and reports enrollment of 44 participants. Its primary outcome description concerns men undergoing androgen deprivation therapy for prostate adenocarcinoma. Further eligibility details and the characteristics of enrolled participants are not reported in the registry record.
Intervention
Each group received a GnRH analogue as a three-month depot, scheduled every three months for one year. The schedules differed in the timing and frequency of Zometa, also called zoledronic acid in the secondary-outcome description. One group received a single 4 mg intravenous dose seven days before androgen deprivation therapy began. Another received a single 4 mg dose at month 6. The third received 4 mg monthly for six months, beginning in month 6.
Comparator
The registry compares the schedule starting seven days before androgen deprivation therapy with the schedule starting at month 6 and with the schedule given monthly during months 6–11. There was no listed group without Zometa: all three groups received a Zometa schedule as well as the GnRH analogue. The comparison therefore addresses timing and schedule, not Zometa versus no Zometa.
Primary question
The primary outcome asks how many participants had either an increase or a decrease in bone mineral density at the lumbar spine and femoral neck during a two-year timeframe. The description says measurements were made at four locations at six-month intervals for 24 months. The posted results count participants, but do not report the magnitude or direction of each change. Other stated interests include bone-turnover markers, immune markers, prostate-specific antigen measurements, and prostate antigen-specific IgG responses.
3. Trial Design
This is a randomized, phase II, parallel-group trial with no masking listed in the registry. Enrollment was 44. The study is marked completed; the registry lists its start as 2003-04 and primary completion as 2011-03. The sponsor is the University of Wisconsin, Madison. The trial compared three Zometa schedules, with all groups also receiving a GnRH analogue three-month depot every three months for one year.
The first schedule used a single 4 mg Zometa infusion over 15 minutes seven days before androgen deprivation therapy began. The second used a single 4 mg infusion over 15 minutes at month 6. The third used Zometa monthly for six months, beginning in month 6; its description also specifies administration over 15 minutes. The posted outcome counts are 14 participants for the first schedule and 15 for each of the other schedules.
These are active-schedule comparisons. The record does not list a placebo group or a group receiving androgen deprivation therapy without Zometa. Randomization is reported, but the method of sequence generation, allocation concealment, and any stratification are not reported in the registry record. The reason for choosing the enrollment target, including any sample-size justification, is not reported in the registry record. The treatment schedule descriptions do not establish adherence, crossover, or treatment discontinuation patterns; those details are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: Of the 44 subjects enrolled, one withdrew from the study prior to receiving any study treatment. As a result there were 43 subjects who received at least one dose of study medication.
Overall Study
| Stage | Zometa Given 7 Days Prior to Beginning ADT | Zometa Given at Month 6 | Zometa Given Monthly x 6 Months |
|---|---|---|---|
| STARTED | 14 | 15 | 14 |
| COMPLETED | 14 | 14 | 12 |
| NOT COMPLETED | 0 | 1 | 2 |
Reasons for not completing this period:
| Reason | Zometa Given 7 Days Prior to Beginning ADT | Zometa Given at Month 6 | Zometa Given Monthly x 6 Months |
|---|---|---|---|
| Withdrawal by Subject | 0 | 1 | 1 |
| Physician Decision | 0 | 0 | 1 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Zometa Given 7 Days Prior to Beginning ADT | Zometa Given at Month 6 | Zometa Given Monthly x 6 Months | Total |
|---|---|---|---|---|---|
| Participants analysed | 14 | 15 | 14 | 43 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 11 | 11 | 10 | 32 |
| Age, Categorical: >=65 years | Participants | 3 | 4 | 4 | 11 |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 14 | 15 | 14 | 43 |
| Gleason Score of 8 or more | participants | 3 | 4 | 8 | 15 |
| Participants with evidence of osteopenia/osteoporosis | participants | 6 | 4 | 5 | 15 |
6. Primary Endpoint
The registry lists the primary outcome as The Number of Subjects Who Had Either an Increase or Decrease on Bone Mineral Density of the Lumbar Spine and Femoral Neck in Men Undergoing Androgen Deprivation Therapy for Prostate Adenocarcinoma., measured over 2 years.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is expressed as the number of participants who had either an increase or a decrease in bone mineral density of the lumbar spine and femoral neck while undergoing androgen deprivation therapy. Bone mineral density is relevant to the stated trial question because the study is examining skeletal measurements in the setting of this therapy and different Zometa schedules. The registry says bone mineral density was measured at four locations at six-month intervals for 24 months, with a two-year outcome timeframe.
The posted endpoint is a participant count rather than a continuous measurement of the amount of bone mineral density change. The available description does not define the threshold for a “significant” change, nor does it specify how an increase and a decrease are combined into the reported count. The arm results show counts equal to the listed arm sizes, and the comparisons encode an event proportion of 1.0 in both schedules being compared. However, they do not provide the underlying measurements, the direction of change for individual participants, or separate results by measurement location or visit.
As a result, the endpoint can describe the recorded occurrence of a change according to the registry’s coding, but it cannot by itself convey how large the changes were or whether they followed a common pattern across locations and time. Those details are not reported in the registry record.
7. Results Posted in the Registry
- Zometa Given at Month 6: 100.0% (15/15) versus 100.0% (14/14) on control; risk difference 0.0 percentage points (95% CI 0.0 to 0.0), risk ratio 1.00 (1.00–1.00); unadjusted two-proportion z-test p = n/a.
- Zometa Given Monthly, Months 6-11: 100.0% (15/15) versus 100.0% (14/14) on control; risk difference 0.0 percentage points (95% CI 0.0 to 0.0), risk ratio 1.00 (1.00–1.00); unadjusted two-proportion z-test p = n/a.
Risk difference: Zometa Given at Month 6
95% CI: 0.0 to 0.0 percentage points
Recalculated from the posted summary statistics
8. Statistical Interpretation
The registry reports 14 participants in the schedule receiving Zometa seven days before androgen deprivation therapy and 15 in each of the schedules starting at month 6. For the primary binary outcome, the posted count is 14 of 14 in the first schedule and 15 of 15 in each comparison schedule. The comparison of the month 6 schedule with the pre-therapy schedule has a risk difference of 0.0, with a confidence interval from 0.0 to 0.0. The comparison of the monthly months 6–11 schedule with the pre-therapy schedule also has a risk difference of 0.0, with a confidence interval from 0.0 to 0.0. Each comparison reports an event proportion of 1.0 in both arms and a risk ratio of 1.0.
These figures describe the coded event counts in the posted results. They do not show that the bone mineral density values were identical between participants or treatment schedules. The endpoint is described as counting people with either an increase or a decrease, and all participants in each arm are counted as having the event. That summary loses information about direction, magnitude, measurement location, and visit-specific pattern. The record does not state how “increase or decrease” was operationalized or what threshold defined a meaningful change.
The estimated risk differences and their reported intervals are exactly zero in these posted comparisons. That numerical precision should be read in light of the small arm counts and the way the binary outcome is reported. A confidence interval can reflect uncertainty under a statistical model and the data structure used in the calculation; it does not restore information absent from the endpoint coding. The registry does not explain why the reported intervals have zero width, and the underlying participant-level measurements are not reported in the registry record.
The comparisons are between active Zometa schedules. They do not estimate the contrast between Zometa and no Zometa, and they do not isolate the effects of androgen deprivation therapy from the effects of Zometa. The registry lists secondary interests in bone-turnover markers, immune markers, PSA, and prostate antigen-specific IgG responses, but the posted result details in this record do not provide estimates for those outcomes. The three secondary outcome descriptions are not enough to establish their observed results.
The registry record lists no analyses in its analysis count. It also does not report an inferential analysis plan, adjustment for repeated measurements, or an explanation of the comparison method. Thus, the numerical comparisons can be described as posted, but their assumptions and relationship to a prespecified analysis plan are not documented. These results are descriptive of the posted endpoint coding and should not be extended to unreported measurements or outcomes.
9. Statistical Methods Explained
Randomization assigns participants to treatment schedules by chance, which is intended to support fair comparisons of groups. The registry identifies the trial as randomized and parallel, but does not report how the random sequence was generated, how assignments were concealed, or whether the groups were balanced using stratification. Those implementation details are not reported in the registry record. Masking is listed as none, so the trial is described as unmasked. The record does not say whether outcome assessors were masked separately from participants or investigators.
What does a risk difference describe?
For a binary outcome, a risk difference is the event proportion in one group minus the event proportion in the comparison group. It is expressed on the probability scale, and a value of zero means the two reported proportions are equal. In these posted comparisons, each arm has an event proportion of 1.0 and the risk difference is 0.0. The risk ratio expresses one event proportion relative to the other; the posted value is 1.0 for each comparison. These are summaries of the reported binary counts, not summaries of the amount of bone mineral density change.
A binary endpoint simplifies a complex measurement into whether a participant is counted as having an event. That can be useful when the event definition is clinically or scientifically meaningful and consistently applied. It also removes detail: a small change and a large change may be counted alike, while an increase and a decrease may be combined if the endpoint is coded as “either.” The registry description does not give a threshold for change or separate the directions, so the interpretation of the event definition is limited.
Why can repeated measurements matter?
The record says measurements were taken at four locations at six-month intervals for 24 months. Repeated measurements on the same participant are related rather than independent observations. A method for longitudinal data can account for that within-participant relationship and make use of the measurement pattern over time. The record does not report whether such a model was used, how measurements at the locations were combined, or whether the primary analysis used a single visit, a change from baseline, or a summary across visits. Those details are not reported in the registry record.
The posted comparison is a binary count comparison, while the outcome description refers to repeated bone mineral density measurements. This difference in form makes the operational definition important: the reader needs to know how measurements became a participant-level event. That definition is not reported in the registry record. Without it, the count cannot be interpreted as a specific amount or trajectory of change.
What does a confidence interval contribute?
A confidence interval gives a range of estimates compatible with the data and the method used, under the assumptions of that method. It helps distinguish an estimate from its uncertainty. In these comparisons, the reported risk difference and both interval limits are 0.0. The record does not describe the interval calculation or explain the zero-width intervals. In general, when event proportions are at a boundary, the choice of method and data structure can matter. That is a general statistical consideration, not a claim about the specific calculation used for this registry result.
The posted comparisons are not accompanied by listed analyses in the registry’s analysis count. The method behind the comparisons, any adjustment for covariates, and any treatment of repeated measures are not reported in the registry record. No independent recalculation is needed to describe the results, and the record does not indicate a discrepancy between its reported result and a recalculated one.
How should planning illustrations be understood?
Sample-size planning asks how many participants might be needed under stated assumptions to detect an effect of interest with a chosen error rate and power. The planning assumptions described for this trial use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is expressed as a stated fraction of the observed effect. Such calculations are planning illustrations based on the observed effect, not the trial’s own design justification and not observed power. The registry does not report the trial’s original sample-size justification or its planning assumptions.
These illustrations depend on assumptions about the effect, allocation, outcome distribution, and analysis. They should not be interpreted as evidence that the trial had a particular probability of finding a result. In particular, calculations based on the observed effect do not change what the trial actually observed or compensate for the limited detail in the binary endpoint. Any original design calculation, interim-analysis plan, or formal statistical analysis plan is not reported in the registry record.
10. Confidence Intervals and Precision
The primary comparisons report risk differences of 0.0, with confidence intervals from 0.0 to 0.0, when the pre-therapy schedule is compared with either schedule beginning at month 6. Both comparisons also report event proportions of 1.0 in each arm and risk ratios of 1.0. These posted values indicate no difference in the coded event proportions in the comparisons as reported. They do not indicate that the underlying bone mineral density measurements were identical.
A confidence interval is generally used to communicate uncertainty around an estimate, conditional on the statistical method and assumptions. The reported intervals have no width, but the registry does not explain the interval method or why those limits coincide with the estimate. The event count is at the full arm size in each group. When an endpoint is recorded at a boundary in this way, inference may depend strongly on the method used; this is a general statistical point. The registry does not provide enough detail to assess the calculation behind the reported intervals.
Precision is also constrained by the size and content of the posted result. The arm counts are 14 and 15, and the outcome is a binary count of participants with a change rather than the amount of change. No standard deviations, distributions, individual measurements, or visit-specific estimates are reported. The registry description does not give the threshold used to define a change or separate increase from decrease. Therefore, the reported interval addresses only the risk difference for the coded event, not uncertainty about the magnitude or direction of bone mineral density change over time.
The confidence intervals should be read as part of the registry’s reported comparison, not as a complete account of precision for every aspect of the clinical question. The method and analysis population are not reported in the registry record.
11. Multiplicity, Missing Data and Analysis Populations
The trial description involves more than one outcome domain. Alongside the primary bone mineral density outcome, the registry lists secondary outcomes concerning peripheral blood markers of bone turnover, immune markers, and PSA decreases after zoledronic acid before androgen deprivation therapy. The study summary also mentions prostate antigen-specific IgG responses and serial PSA measurements. The registry reports four outcome measures and three posted secondary outcome descriptions, but the record does not describe a multiplicity strategy.
Multiplicity arises when several outcomes, treatment comparisons, measurement locations, or time points are examined. Considering many results can increase the chance that at least one appears noteworthy by chance. A prespecified hierarchy, adjustment method, or clear distinction between confirmatory and exploratory outcomes can help readers interpret multiple tests. Any such plan, including adjustment for the two reported comparisons or for the repeated measurements at different locations and visits, is not reported in the registry record. The posted results do not include analysis entries in the registry’s analysis count.
Missing-data handling is also not described. The registry gives outcome counts of 14, 15, and 15 for the three arms, but does not define the analysis population or explain whether all randomized participants were included, whether any measurements were unavailable, or how missing visits would be handled. The listed counts should not be assumed to establish complete follow-up at every measurement location and time point.
The record does not report an intention-to-treat definition, a per-protocol analysis, imputation procedures, sensitivity analyses, or reasons for missing measurements. It also does not explain whether participants who discontinued treatment remained in outcome follow-up. These omissions matter because repeated-measurement results can be affected by which observations are available and how incomplete follow-up is handled. Without those details, readers cannot assess the impact of missing data or determine which analysis population underlies the reported counts.
12. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Zometa Given 7 Days Prior to Beginning ADT | 2 | 14 | 14.3% |
| Zometa Given at Month 6 | 2 | 15 | 13.3% |
| Zometa Given Monthly x 6 Months | 2 | 15 | 13.3% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Zometa Given 7 Days Prior to Beginning ADT | 14 of 14 |
| Zometa Given at Month 6 | 15 of 15 |
| Zometa Given Monthly x 6 Months | 15 of 15 |
Most frequent serious adverse event terms
| Event term | Organ system | Zometa Given 7 Days Prior to Beginning ADT | Zometa Given at Month 6 | Zometa Given Monthly x 6 Months |
|---|---|---|---|---|
| Syncope (fainting) | Nervous system disorders | 1 of 14 | 1 of 15 | 0 of 15 |
| Low Platelets | Blood and lymphatic system disorders | 1 of 14 | 0 of 15 | 0 of 14 |
| Creatine phosphokinase | Metabolism and nutrition disorders | 1 of 14 | 0 of 15 | 0 of 14 |
| Hypercalcemia | Metabolism and nutrition disorders | 1 of 14 | 0 of 15 | 0 of 14 |
| Musculoskeletal/Soft Tissue - Other (Complication of prior hip replacement) | Musculoskeletal and connective tissue disorders | 1 of 14 | 0 of 15 | 0 of 14 |
| Chest Pain (non-cardiac and non-pleuritic) | General disorders | 1 of 14 | 0 of 15 | 0 of 14 |
| Musculoskeletal-Other (fracture) | Musculoskeletal and connective tissue disorders | 0 of 14 | 1 of 15 | 0 of 14 |
| Creatinine | Renal and urinary disorders | 1 of 14 | 0 of 15 | 0 of 14 |
| Infection without neutropenia | Infections and infestations | 0 of 14 | 1 of 15 | 0 of 14 |
| Musculoskeletal-other (shoulder) | Musculoskeletal and connective tissue disorders | 1 of 14 | 0 of 15 | 0 of 14 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Zometa Given 7 Days Prior to Beginning ADT | Zometa Given at Month 6 | Zometa Given Monthly x 6 Months |
|---|---|---|---|---|
| Hot flashes | Endocrine disorders | 11 of 14 | 11 of 15 | 11 of 15 |
| Fatigue | General disorders | 6 of 14 | 8 of 15 | 7 of 15 |
| Arthralgia | Musculoskeletal and connective tissue disorders | 7 of 14 | 5 of 15 | 3 of 15 |
| Bone pain | Musculoskeletal and connective tissue disorders | 6 of 14 | 3 of 15 | 5 of 15 |
| Myalgia | Musculoskeletal and connective tissue disorders | 6 of 14 | 3 of 15 | 3 of 15 |
| Edema | Cardiac disorders | 3 of 14 | 5 of 15 | 2 of 15 |
| Pain - other | Musculoskeletal and connective tissue disorders | 2 of 14 | 3 of 15 | 4 of 15 |
| Nausea | Gastrointestinal disorders | 1 of 14 | 1 of 15 | 6 of 15 |
| Neuropathy-sensory | Nervous system disorders | 4 of 14 | 2 of 15 | 2 of 15 |
| Constipation | Gastrointestinal disorders | 1 of 14 | 3 of 15 | 3 of 15 |
Serious events with the highest arm-level rate: low platelets (7.1%), creatine phosphokinase (7.1%), hypercalcemia (7.1%), musculoskeletal/soft tissue - other (complication of prior hip replacement) (7.1%), chest pain (non-cardiac and non-pleuritic) (7.1%).
The registry lists 2 participants with serious adverse events in each treatment group. The corresponding groups at risk are 14 for the schedule given seven days before androgen deprivation therapy and 15 for each schedule beginning at month 6. Other adverse events are recorded for 14 of 14, 15 of 15, and 15 of 15 participants, respectively. These are reported participant counts; they do not establish that every event was caused by treatment.
The serious-event terms listed include Low Platelets, Creatine phosphokinase, Hypercalcemia, Musculoskeletal/Soft Tissue - Other (Complication of prior hip replacement), Chest Pain (non-cardiac and non-pleuritic), and Creatinine. Each term is listed with 7.1%. The record does not clarify whether the terms refer to distinct participants, whether participants could contribute more than one event, or the denominator used for each term. No death count is reported in the registry record.
These safety figures describe what is recorded and should not be treated as a comparative safety analysis. The groups are small, all participants received an active Zometa schedule, and the record does not provide event timing, severity grading beyond the serious-event category, attribution, or detailed follow-up. The counts alone do not establish causal relationships or rule out uncommon events.
13. What the Result Does, and Does Not, Mean
The posted primary results show the same coded event proportion in each of the three Zometa schedules: all listed participants in each arm are counted as having the binary outcome. The two comparisons against the schedule given seven days before androgen deprivation therapy report risk differences of 0.0, confidence intervals from 0.0 to 0.0, and risk ratios of 1.0. This is a description of the registry’s binary outcome coding, not a statement that bone mineral density values were unchanged or identical.
The endpoint wording combines an increase or a decrease, and the record does not report the amount or direction of change. It also does not provide separate estimates for lumbar spine and femoral neck, the four measurement locations, or the repeated time points. Consequently, the posted count does not reveal the trajectory of bone mineral density or whether patterns differed by location or time.
The study compares timing and frequency among active Zometa schedules while participants also receive a GnRH analogue. It does not compare Zometa with no Zometa, and the posted primary result cannot answer whether Zometa itself changes bone mineral density relative to no Zometa. The secondary outcomes are listed, but their numerical results are not described in this record.
The result does not establish equivalence of the schedules. A claim of equivalence would require a defined margin and an analysis designed to assess whether differences fall within that margin; such a margin and analysis are not reported in the registry record. The reported zero differences are specific to the binary event proportions as posted. Nor does the result establish that there was no change in bone mineral density: the primary endpoint counts participants with either direction of change, and all are recorded as having an event.
Overall, the record offers a limited summary of participant counts across three schedules. The underlying measurements, operational definition, analysis plan, and details of follow-up are not reported in the registry record, limiting what can be concluded beyond those counts.
14. Why This Trial Matters Statistically
This trial is statistically informative as an example of how endpoint definition shapes interpretation. Bone mineral density is measured repeatedly and at multiple locations according to the registry description, but the primary result is presented as a participant count for either an increase or a decrease. That binary summary does not preserve the direction, size, or timing of change. Clear reporting of how continuous measurements are translated into a binary event is essential for readers to understand what the estimate represents.
The design also highlights the distinction between comparing active schedules and comparing a treatment with no treatment. Each group received Zometa, with differences in timing and frequency, alongside a GnRH analogue. The comparisons therefore address schedule contrasts. They do not answer a Zometa-versus-no-Zometa question, regardless of how similar the posted event proportions appear.
Repeated outcomes create further statistical questions: how measurements within a participant are modeled, how visits and locations contribute to the primary endpoint, and how incomplete follow-up is treated. The registry does not report those methods. In a small phase II trial with 14 or 15 participants per posted arm, the definition and analysis of each outcome are particularly important for understanding the limits of the estimates.
Finally, a confidence interval with identical limits and estimate may look exceptionally precise, but precision must be judged in relation to the outcome coding and calculation method. The record does not describe why the intervals have zero width. Transparent reporting of the analysis method, uncertainty calculation, and measurement-level results would help distinguish a boundary-coded binary summary from evidence about the underlying continuous measurements.
15. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The primary outcome description leaves key interpretive details unspecified. It refers to participants with either an increase or a decrease in bone mineral density, but does not define the threshold for a change, say whether the directions were combined, or explain how a participant was classified across multiple measurement locations and visits. The posted counts therefore cannot be translated into a measure of change magnitude or direction.
Although measurements are described at four locations at six-month intervals for 24 months, results are not reported by location or visit. The record does not provide baseline values, change scores, distributions, or variability measures. It also does not explain how repeated measurements were analyzed or whether the primary endpoint was based on a particular visit or an overall participant-level rule.
The posted comparisons involve small groups, with 14 participants in one arm and 15 in each other arm. The record does not report the original sample-size justification, randomization procedure, allocation concealment, or a statistical analysis plan. It does not describe the analysis population, missing-data handling, attrition, adherence, or any crossover. These omissions limit assessment of bias, precision, and the effect of incomplete follow-up.
All arms received a Zometa schedule, so there is no listed no-Zometa comparator. The primary comparisons cannot isolate the effect of Zometa from the background therapy or assess a contrast against no Zometa. The registry lists several secondary outcome domains, but the corresponding numerical results and any multiplicity plan are not reported in the registry record. These limitations concern what can be interpreted from the record and do not establish that any particular method or result was absent from other study materials.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Zometa on Bone Mineral Density in Prostate Cancer Patients Undergoing Androgen Ablation Therapy — NCT00582556.
- Registry record last updated 2019-11-26; status last verified 2014-06.
- Results first posted 2014-05-12.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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19. Record Summary
NCT00582556 is a completed randomized, unmasked, parallel phase II trial sponsored by the University of Wisconsin, Madison. It enrolled 44 participants with prostate cancer undergoing androgen deprivation therapy. The three groups received a GnRH analogue for one year and differed in the timing and frequency of Zometa administration.
The primary outcome counts participants with either an increase or a decrease in bone mineral density of the lumbar spine and femoral neck over a two-year timeframe. The posted arm counts are 14, 15, and 15, with every listed participant counted as having the event. Both comparisons against the pre-therapy Zometa schedule report a risk difference of 0.0 and a risk ratio of 1.0. The record does not provide the amount or direction of bone mineral density change, detailed analysis methods, or results for the listed secondary outcomes.