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 Bone Mineral Density Study In Patients With Chronic Obstructive Pulmonary Disease. DISKUS® Inhaler is a Trademark of the GSK Group of Companies. (NCT00355342), a randomized phase 4 study. The primary outcome is Percent Change From Baseline in Bone Mineral Density (BMD) at the Lumbar Spine L1-L4.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00355342 |
| Phase | Phase 4 |
| Condition | Pulmonary Disease, Chronic Obstructive |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 186 |
| Arms in the primary outcome | n/a |
| Lead sponsor | GlaxoSmithKline |
| Results posted | Yes |
2. Clinical Question
Population
The trial enrolled subjects with chronic obstructive pulmonary disease (COPD). The registry reports enrollment of 186. The primary-outcome analysis population was narrower than all randomized participants: it included randomized participants who were at least 50% compliant with study drug and had a post-baseline bone mineral density (BMD) scan. Only participants available at the specified time points were analyzed.
Intervention
The intervention was fluticasone propionate/salmeterol 250/50 mcg, given by DISKUS inhaler as one inhalation twice daily, in the morning and evening. The arm description specifies treatment for 156 Weeks. Fluticasone propionate is the steroid component whose effect on bone density motivated the study question.
Comparator
The comparator was salmeterol 50 mcg, formulated with lactose and administered through the DISKUS inhaler as one inhalation twice daily, in the morning and evening, for 156 Weeks. This active-comparator design contrasts the combination product with salmeterol alone; it does not compare either treatment with no treatment.
Primary question
The primary question was whether percent change from baseline in BMD at the lumbar spine L1-L4 differed between the treatment groups across the scheduled assessments. The stated assessment times were baseline and Weeks 26, 52, 78, 104, 130, and 156. The registry record does not report the primary-outcome values or a treatment comparison, so the direction, size, and precision of any difference cannot be described.
The trial was registered as NCT00355342 and sponsored by GlaxoSmithKline. Its stated purpose was to evaluate the effect of the steroid component of an inhaled product on BMD in people with COPD. BMD is a measure of bone density, and the registry describes it as reflecting bone strength through calcium content. The clinical question is therefore about a measured bone-density outcome, not about lung function, fractures, or symptoms. Lung function tests are mentioned in the study summary, but they are not identified as the primary endpoint.
3. Trial Design
This was a phase 4, randomized, double-blind, parallel-group clinical trial. Participants were assigned to receive either fluticasone propionate/salmeterol 250/50 mcg twice daily or salmeterol 50 mcg twice daily, both through a DISKUS inhaler. Randomization means assignment was intended to allocate participants to study groups by chance; double blinding means the registry identifies the study as masked for participants and investigators, without describing who specifically remained unaware of assignment. The parallel-group model means participants were allocated to a treatment arm rather than described as switching between the study treatments.
The registry lists enrollment of 186 and status as completed. The start date was 2004-04-28 and primary completion was 2007-09-06. These dates describe the registered study timeline; they do not establish when individual participants completed treatment or follow-up. The arm descriptions specify treatment for 156 Weeks. The study summary says the study would last up to 3 years and describes clinic visits, lung function tests, and bone scans.
The comparison is between a combination product containing fluticasone propionate and salmeterol, and salmeterol alone. Both arms used the same inhaler device, which makes the contrast relevant to the additional steroid component, while the registry's outcome remains the measured BMD change. No placebo arm is listed. The record does not report allocation concealment procedures, the randomization sequence method, or details about which parties were masked.
The primary-outcome description specifies DEXA scans at baseline and every 26 weeks during the study, with acceptable baseline measurements obtained before the first randomized study-medication dose. Baseline was defined as collections taken on Day 1 of the treatment period. Although the record gives the outcome schedule and analysis-population definition, it does not report the numerical BMD findings or a between-arm estimate. It also does not report the statistical model used for the primary analysis.
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: A total of 247 participants were screened for this study, of whom 61 were screen failures and 186 participants were randomized in the study.
Overall Study
| Stage | Salmeterol 50 mcg BID | Fluticasone Propionate/Salmeterol 250/50 mcg BID |
|---|---|---|
| STARTED | 94 | 92 |
| COMPLETED | 55 | 56 |
| NOT COMPLETED | 39 | 36 |
Reasons for not completing this period:
| Reason | Salmeterol 50 mcg BID | Fluticasone Propionate/Salmeterol 250/50 mcg BID |
|---|---|---|
| Adverse Event | 13 | 15 |
| Lost to Follow-up | 4 | 2 |
| Withdrawal by Subject | 14 | 11 |
| Sponsor terminated study | 2 | 2 |
| Overcompliant-PI discretion | 1 | 0 |
| Use of prohibited medication | 1 | 0 |
| COPD exacerbation | 1 | 1 |
| Dispensed wrong study drug kit | 1 | 0 |
| Non-compliance with Dexa scans | 1 | 0 |
| Withdrawal by participant and physician | 1 | 0 |
| Participant relocated | 0 | 1 |
| Participant discontinued study drug | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: The Safety population - Safety population was defined as all randomized participants who are at least 50% compliant with taking study drug and have a post-Baseline BMD scan. Only those participants available at the specified time points were analyzed.
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 | Salmeterol 50 mcg BID | Fluticasone Propionate/Salmeterol 250/50 mcg BID | Total |
|---|---|---|---|---|
| Participants analysed | 94 | 92 | 186 | |
| Age, Continuous | Years | 65.9 (SD 9.52) | 65.4 (SD 8.36) | 65.6 (SD 8.94) |
| Sex: Female, Male: Female | Participants | 35 | 37 | 72 |
| Sex: Female, Male: Male | Participants | 59 | 55 | 114 |
| Race/Ethnicity, Customized: Race – American Hispanic | Participants | 1 | 0 | 1 |
| Race/Ethnicity, Customized: Race – Black | Participants | 1 | 4 | 5 |
| Race/Ethnicity, Customized: Race – South Asian | Participants | 0 | 1 | 1 |
| Race/Ethnicity, Customized: Race – White/Caucasian | Participants | 92 | 87 | 179 |
6. Primary Endpoint
The registry lists the primary outcome as Percent Change From Baseline in Bone Mineral Density (BMD) at the Lumbar Spine L1-L4, measured over Baseline and Week 26, 52, 78, 104, 130, and 156.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Error |
| Unit | Percent Change |
| Endpoint classification | Continuous Endpoint |
The primary endpoint was percent change from baseline in BMD at the lumbar spine, measured across vertebrae L1-L4. BMD is a quantitative measure of bone density. The registry describes it as reflecting bone strength through calcium content and notes that BMD testing can detect osteopenia and osteoporosis. The outcome therefore captures a change in a bone-density measurement rather than a clinical event such as fracture.
DEXA was used to measure lumbar-spine BMD. The registry describes scans at baseline and at Weeks 26, 52, 78, 104, 130, and 156. Baseline was defined as measurements collected on Day 1 of the treatment period, and acceptable DEXA measurements were required before the first dose of randomized study medication. Change from baseline was calculated by subtracting the baseline value from the value at the indicated time point. The reported outcome parameter was the mean, with standard error as the stated dispersion measure.
In general, a continuous measure such as BMD can describe gradual changes in a biological quantity, rather than reducing the assessment to whether an event did or did not occur. Repeated scheduled measurements can show how the measure changes over follow-up. However, the registry record does not report the numerical endpoint results, so it is not possible to describe the observed mean change, compare the groups, or assess the precision of a treatment contrast. BMD is the endpoint studied; the record does not establish that it is a direct measure of fractures or other patient-important outcomes.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the endpoint and the planned measurement schedule, but it does not report the primary-outcome values. As a result, the posted results do not support a description of which arm had a larger or smaller mean percent change in lumbar-spine BMD, how large any difference was, or how uncertain the estimate might be. A direction of effect, treatment contrast, confidence interval, and significance test for the primary endpoint are not reported in the registry record. No conclusion about the primary comparison can be drawn from the endpoint description alone.
The primary outcome covers baseline and several follow-up times: Weeks 26, 52, 78, 104, 130, and 156. This is a repeated-measure setting, in which measurements from the same participant over time are related. In general, interpretation depends on whether the analysis compares groups at particular times, models the trajectory over time, or uses another prespecified summary. The registry record does not report which approach was used, and it does not identify a single time point as the sole primary comparison. The primary-outcome description alone therefore cannot establish whether any apparent change over time would represent a treatment-group difference.
The primary analysis population is described as the safety population, defined as randomized participants who were at least 50% compliant with study drug and had a post-baseline BMD scan. Only those available at the specified time points were analyzed. This definition is important when interpreting any reported outcome: the analyzed set was conditioned on adherence and availability of a post-baseline scan. The record does not provide the number analyzed at each time point or describe how missing measurements were handled beyond analyzing those available at the specified times.
Safety information is reported separately from the BMD endpoint. For serious adverse events, the registry lists 33 affected participants among 94 at risk in the salmeterol group and 32 among 92 at risk in the combination-product group. It also lists other adverse events and deaths. These figures describe safety counts, not the primary BMD comparison. They do not establish that an event was caused by study medication, and the record does not provide an adjusted comparison of the groups for these outcomes.
Overall, the available record permits a description of the trial design, treatment arms, endpoint, and analysis population, but not a numerical interpretation of the primary efficacy result. The sponsor's statistical analysis, primary estimates, uncertainty measures, and statistical test are not reported in the registry record. Without them, the results cannot be characterized as favoring either arm or as demonstrating a meaningful difference or similarity.
9. Statistical Methods Explained
The registry describes the endpoint as a mean of a continuous measure and gives standard error as its dispersion measure. It does not report the model or statistical test used to compare the arms. The distinctions below explain general statistical concepts relevant to interpreting this kind of outcome; they are not claims about the trial's unreported analysis.
What does the mean describe?
For a continuous endpoint, a mean summarizes the central value of measurements in a group. Here, the target quantity is percent change from baseline in lumbar-spine BMD. A mean change can convey the average pattern among participants included in the analysis, but it does not show the full distribution of individual changes. Participants may have changes that differ substantially from the group average.
A treatment comparison would generally require a contrast between the groups, such as a difference in their mean changes or a model-based estimate at a scheduled time. The registry lists the endpoint and its time points, but the comparison estimate is not reported in the registry record. The endpoint definition should not be mistaken for an observed result.
What does the standard error convey?
In general, a standard error describes the statistical precision of an estimated mean. It is not the same as the spread of individual participants' measurements: a standard deviation describes participant-to-participant variability, while a standard error concerns uncertainty in an estimated summary. The registry specifies standard error as the dispersion measure but does not report its numerical values for the BMD outcome.
A confidence interval is a range of values compatible with the data and the assumptions of the analysis, expressed with a stated confidence level. It can help readers judge both the possible magnitude and precision of an estimated treatment contrast. No confidence interval for the primary outcome is reported in the registry record. Without an estimate and interval, it is not possible to assess whether the data are compatible with a broad range of effects or a more narrowly estimated result.
Why does the measurement schedule matter?
The endpoint was assessed at baseline and Weeks 26, 52, 78, 104, 130, and 156. Repeated observations from a participant are generally correlated because they come from the same person. A statistical method that handles repeated observations should account for that dependence; treating each measurement as if it came from an unrelated participant can misrepresent uncertainty. This is a general consideration, not a description of the method used in this trial. The registry record does not report whether the analysis modeled repeated measurements, performed separate comparisons at each time, or used another approach.
In general, a trajectory analysis can estimate changes over time and compare patterns between groups, whereas a time-specific comparison focuses on a selected assessment. The choice affects the meaning of the estimate and the handling of multiple assessments. Since the registry lists multiple time points and does not report a single result or analysis method, the statistical interpretation cannot be reconstructed from the record.
What is over-dispersion, and is it relevant?
Over-dispersion describes variation in count data that is greater than a simple statistical model expects. It matters for outcomes such as counts of events, where ignoring excess variability can produce uncertainty estimates that are too small. The primary endpoint is a continuous BMD measure, not an event count, so over-dispersion is not the central issue for that outcome. In general, the appropriate variance assumptions depend on the outcome type and analysis model. The registry does not report enough detail to assess model assumptions for the BMD analysis.
How should planning illustrations be understood?
Sample-size planning calculations are hypothetical design illustrations, not observed findings and not evidence that a completed trial had a particular probability of detecting an effect. The stated planning assumptions describe a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is described as a stated fraction of the observed effect. The registry record does not report its own sample-size justification or identify these planning assumptions as the trial's original design plan. Any planning illustration should therefore be read as conditional on its assumptions, not as the trial's observed power or as a replacement for the sponsor's analysis.
In general, a sample-size calculation asks how much information might be needed to detect a chosen effect under specified assumptions. The answer changes with the target effect, variability, significance level, power target, and design. A planning calculation cannot supply the missing primary-outcome estimate. It also does not resolve uncertainty about missing measurements or multiplicity.
What analysis details are missing?
The registry record does not report the primary statistical test, model specification, covariate adjustment, treatment-effect estimate, confidence interval, or p-value. It also does not describe whether the analysis used an intention-to-treat approach, how protocol deviations were handled, or whether interim analyses occurred. These items should not be inferred from the randomized, double-blind design or from the endpoint schedule. In general, such details help explain the target estimand, the assumptions supporting inference, and the handling of repeated observations and missing data. Their absence means the posted record supports a descriptive account of the trial question, but not a reconstruction of the primary statistical analysis.
10. Multiplicity, Missing Data and Analysis Populations
The primary endpoint was measured at baseline and at Weeks 26, 52, 78, 104, 130, and 156. The registry also lists percent change from baseline in BMD at the total hip as a secondary outcome. Multiple outcomes and assessment times can create multiplicity: in general, making several statistical comparisons increases the chance that at least one result appears notable by chance if no adjustment or prespecified testing strategy is used. The record does not report a multiplicity adjustment, a testing hierarchy, or which time point was designated as the principal primary comparison. Those details are not reported in the registry record.
Missing measurements are also relevant because the primary analysis population included participants with a post-baseline BMD scan and analyzed only those available at the specified time points. The registry does not report the number of participants contributing data at each assessment, reasons for missing scans, or a method for imputing missing measurements. In general, analyzing only observed measurements can be sensitive to why observations are missing. If availability is related to health status, adherence, or outcome values, the analyzed participants may not represent all randomized participants in the same way at each time point. This is a general caution, not evidence that any particular missingness mechanism occurred in this trial.
The defined analysis population required at least 50% compliance with study drug and a post-baseline scan. This is the registry's stated population definition; it is not described as an intention-to-treat analysis of all randomized participants. The record does not report a separate analysis population or sensitivity analysis. The way the primary analysis handled participants who did not meet the safety-population criteria is not reported in the registry record. Without the analysis details and outcome results, the influence of population selection, missing data, and multiple assessments cannot be evaluated.
11. 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 |
|---|---|---|---|
| Salmeterol 50 mcg BID | 33 | 94 | 35.1% |
| Fluticasone Propionate/Salmeterol 250/50 mcg BID | 32 | 92 | 34.8% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Salmeterol 50 mcg BID | 7 of 94 |
| Fluticasone Propionate/Salmeterol 250/50 mcg BID | 5 of 92 |
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 |
|---|---|
| Salmeterol 50 mcg BID | 63 of 94 |
| Fluticasone Propionate/Salmeterol 250/50 mcg BID | 72 of 92 |
Most frequent serious adverse event terms
| Event term | Organ system | Salmeterol 50 mcg BID | Fluticasone Propionate/Salmeterol 250/50 mcg BID |
|---|---|---|---|
| Chronic obstructive pulmonary disease | Respiratory, thoracic and mediastinal disorders | 11 of 94 | 11 of 92 |
| Pneumonia | Infections and infestations | 4 of 94 | 6 of 92 |
| Myocardial infarction | Cardiac disorders | 0 of 94 | 5 of 92 |
| Chest pain | General disorders | 1 of 94 | 2 of 92 |
| Coronary artery disease | Cardiac disorders | 3 of 94 | 0 of 92 |
| Lobar pneumonia | Infections and infestations | 2 of 94 | 1 of 92 |
| Syncope | Nervous system disorders | 1 of 94 | 2 of 92 |
| Anaemia | Blood and lymphatic system disorders | 1 of 94 | 1 of 92 |
| Atrial fibrillation | Cardiac disorders | 1 of 94 | 1 of 92 |
| Bronchitis | Infections and infestations | 1 of 94 | 1 of 92 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Salmeterol 50 mcg BID | Fluticasone Propionate/Salmeterol 250/50 mcg BID |
|---|---|---|---|
| Nasopharyngitis | Infections and infestations | 21 of 94 | 28 of 92 |
| Sinusitis | Infections and infestations | 15 of 94 | 12 of 92 |
| Upper respiratory tract infection | Infections and infestations | 11 of 94 | 10 of 92 |
| Cough | Respiratory, thoracic and mediastinal disorders | 11 of 94 | 8 of 92 |
| Pharyngolaryngeal pain | Respiratory, thoracic and mediastinal disorders | 6 of 94 | 10 of 92 |
| Bronchitis | Infections and infestations | 7 of 94 | 8 of 92 |
| Arthralgia | Musculoskeletal and connective tissue disorders | 9 of 94 | 5 of 92 |
| Back pain | Musculoskeletal and connective tissue disorders | 7 of 94 | 7 of 92 |
| Headache | Nervous system disorders | 6 of 94 | 8 of 92 |
| Hypertension | Vascular disorders | 6 of 94 | 6 of 92 |
Serious events with the highest arm-level rate: chronic obstructive pulmonary disease (12.0%), pneumonia (6.5%), myocardial infarction (5.4%), coronary artery disease (3.2%), chest pain (2.2%).
The registry reports serious adverse events for each arm as affected participants and participants at risk. In the salmeterol 50 mcg BID arm, 33 of 94 were affected; in the fluticasone propionate/salmeterol 250/50 mcg BID arm, 32 of 92 were affected. The registry also reports other adverse events: 63 of 94 in the salmeterol arm and 72 of 92 in the combination-product arm. Deaths are listed as 7 and 5, respectively. These are separate safety counts and should not be confused with the BMD outcome.
The registry lists serious-event terms with percentages, including chronic obstructive pulmonary disease at 12.0%, pneumonia at 6.5%, myocardial infarction at 5.4%, coronary artery disease at 3.2%, chest pain at 2.2%, and syncope at 2.2%. The record does not specify the denominators for these listed percentages in the information, so they should be read as registry-listed values rather than recalculated group-specific risks.
In general, an adverse event recorded during a trial is not automatically caused by the treatment. These counts do not establish causality, and the registry does not report an adjusted statistical comparison for the safety outcomes. The death counts likewise do not indicate cause or treatment attribution in the record.
12. What the Result Does, and Does Not, Mean
The trial's question concerned the effect of adding fluticasone propionate to salmeterol on BMD in people with COPD. Its primary endpoint was percent change from baseline in lumbar-spine BMD at L1-L4, measured on a schedule extending through Week 156. The design and endpoint are described, but numerical results for the primary outcome are not reported in the registry record. Consequently, the posted information does not establish the size or direction of the observed treatment contrast, nor how precisely it was estimated.
This limitation is important when distinguishing a study question from a study finding. A registered objective explains what investigators intended to evaluate; it does not, by itself, show what the data demonstrated. The use of randomization and blinding describes features of the design, but those features cannot substitute for an effect estimate and uncertainty measure. The record does not report the primary comparison's p-value, confidence interval, or analysis method, so it is not possible to characterize statistical evidence for a difference from the information recorded.
The outcome itself also has a defined scope. BMD is a measure of bone density, and the registry describes it as related to bone strength through calcium content. The primary endpoint is not a direct report of fractures, symptoms, or quality of life. A change in a measured BMD value should not be treated as equivalent to a change in those other outcomes. The registry does not report results for those outcomes in the information described.
The safety counts offer additional information, but they do not answer the primary BMD question. The serious and other adverse-event counts are descriptive registry figures; they are not proof that the study medication caused or prevented any event. Nor do the counts alone provide an adjusted comparison or explain event timing and attribution.
In general, interpreting a completed randomized trial requires the estimated effect, its precision, the analysis population, and the methods used to address repeated measurements and missing data. Here, the record supports an account of the registered question and design, plus selected safety counts, but not a conclusion that either treatment produced a particular BMD result. It also cannot establish that the treatments were equivalent or that any difference was clinically important.
13. Why This Trial Matters Statistically
This trial is statistically instructive because its main outcome is a continuous measure repeated over time. The registry identifies percent change from baseline in lumbar-spine BMD and specifies assessments through Week 156. Such a design raises familiar questions about how to compare groups across follow-up: whether the target is a contrast at a specific time or a difference in the pattern over time, how repeated measurements from the same participant are handled, and how incomplete follow-up affects the analysis.
The registry also illustrates why an endpoint definition is not the same as a result. It states the measurement, time points, summary measure, and population definition, yet the primary outcome values and inferential statistics are not reported in the registry record. Readers can understand what was intended to be measured without being able to evaluate the observed effect or its precision. This distinction is important when reading registry entries alongside clinical conclusions.
The analysis population is another statistically relevant feature. It was defined by randomization, at least 50% compliance, and having a post-baseline scan, with only participants available at each time point analyzed. Such criteria determine which observations contribute to estimates. Without counts analyzed by time point and information about missing-data handling, the consequences of availability and adherence criteria remain uncertain.
Finally, the registry lists both a primary outcome with several time points and a secondary total-hip BMD outcome. Multiplicity and endpoint selection can influence the interpretation of statistical tests, but the record does not report a testing strategy or adjustment. The case underscores that design labels, outcome schedules, and safety counts are not enough to reconstruct the statistical evidence. Transparent reporting of estimates, uncertainty, analysis populations, and methods is needed to make the primary comparison interpretable.
14. 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 main limitation for statistical interpretation is that the registry record does not report numerical results for the primary endpoint. It also does not report a between-arm estimate, confidence interval, p-value, or the primary statistical test. Although the endpoint schedule is specified, the record does not identify a single primary assessment time or explain how results across the repeated assessments were combined or compared.
The analysis population was restricted to randomized participants who were at least 50% compliant with study drug and had a post-baseline BMD scan. Only those available at the specified time points were analyzed. The record does not provide the number analyzed at each assessment, details about reasons for missing measurements, or a missing-data method. It also does not report whether additional analysis populations or sensitivity analyses were used.
The registry lists a secondary total-hip BMD outcome as well as the primary lumbar-spine outcome, but does not report a multiplicity strategy. It does not provide details of the statistical model, covariate adjustment, randomization implementation, allocation concealment, or which parties were masked. It does not report a sample-size justification, interim analyses, or a full statistical analysis plan. These omissions prevent an assessment of the assumptions and inferential procedures used for the main comparison.
Safety information is limited to reported counts and selected serious-event terms with percentages. The record does not provide adjusted comparisons or enough detail to attribute events to treatment. These limitations do not negate the registered study design; they define the boundaries of what can be concluded from the information reported.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Bone Mineral Density Study In Patients With Chronic Obstructive Pulmonary Disease. DISKUS® Inhaler is a Trademark of the GSK Group of Companies. — NCT00355342.
- Registry record last updated 2018-07-02; status last verified 2018-03.
- Results first posted 2018-03-20.
- 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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18. Record Summary
NCT00355342 was a completed, randomized, double-blind, parallel-group phase 4 trial sponsored by GlaxoSmithKline. It enrolled 186 people with chronic obstructive pulmonary disease and compared fluticasone propionate/salmeterol 250/50 mcg twice daily with salmeterol 50 mcg twice daily, both delivered through a DISKUS inhaler.
The primary outcome was mean percent change from baseline in lumbar-spine BMD at L1-L4, measured by DEXA at baseline and Weeks 26, 52, 78, 104, 130, and 156. The primary analysis population required at least 50% study-drug compliance and a post-baseline scan, with only participants available at specified time points analyzed.
The registry reports selected adverse-event counts but does not report numerical primary-outcome results, a treatment-effect estimate, or inferential statistics. Missing-data methods, multiplicity procedures, and the primary statistical model are not reported in the registry record.