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 Study of T3 for the Treatment of Fibromyalgia (NCT00903877), a na na study. The primary outcome is Visual Analogue Scale of Pain Intensity.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00903877 |
| Phase | NA |
| Condition | Fibromyalgia |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 51 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Stanford University |
| Results posted | Yes |
2. Clinical Question
Population
People with fibromyalgia were enrolled. The registry record lists an enrollment of 51. It does not report additional eligibility details or a separate description of the population included in the primary outcome analysis.
Intervention
The intervention was T3, described as the active form of thyroid hormone. The study sequence began with placebo for 4 weeks, followed by T3 at 25 mcg per day for 4 weeks and then T3 at 50 mcg per day for 4 more weeks.
Comparator
Placebo preceded T3 in the same described sequence. This was not a randomized comparison, and the registry record does not describe a separate concurrent control group. The phases should not be read as a like-for-like comparison between randomized groups.
Primary question
The primary measure was pain intensity on a visual analogue scale, assessed at baseline and during placebo and the two T3 dose periods. The study’s stated aims included assessing the feasibility and promise of a future prospective randomized controlled study. Numerical outcome results and analyses are not reported in the registry record.
The clinical question is therefore exploratory: the study sought to characterize the feasibility and promise of investigating T3 in fibromyalgia, while collecting repeated pain ratings across a planned sequence of study periods. The sequence allows ratings at different stages to be described, but it does not by itself establish what would have happened over the same period without T3. Without random allocation to concurrent treatment groups, changes across periods may reflect factors other than the treatment, including time or the order of the phases.
The record names a future controlled study as an aim, rather than documenting that the pilot itself was a randomized efficacy trial. Its clinical question and its design need to be read together: it recorded pain ratings during an ordered placebo-then-T3 sequence, while assessing whether a later controlled study could be conducted. The registry record does not report numerical changes in pain ratings or an estimated treatment effect.
3. Trial Design
The registry record describes a completed pilot double-blind non-randomized clinical trial, but its masking entry is NONE. Allocation is listed as NA, and the study model is single group. These entries indicate that the design is not a randomized, masked comparison of separate treatment groups. The term “double-blind” in the official title does not change the recorded masking entry.
The described sequence was placebo for 4 weeks, followed by T3 at 25 mcg per day for 4 weeks, followed by T3 at 50 mcg per day for 4 more weeks. The primary pain rating was collected at baseline and during the placebo and T3 periods. The listed primary outcome timeframe is 12 weeks. These periods form an ordered sequence; the placebo period is not a concurrent randomized control arm. Consequently, differences between ratings across periods would not isolate a treatment effect in the way a properly randomized comparison can.
The registry lists enrollment as 51 and identifies Stanford University as the sponsor. The study start is recorded as 2009-05, primary completion as 2011-06, and status as COMPLETED. These record entries describe registration and study status, not the number of participants who completed every phase or contributed data to the endpoint; those details are not reported in the registry record.
The stated purpose included determining the feasibility and promise of a future prospective randomized controlled study, including its feasibility, cost, obstacles, and promise. That aim is consistent with the pilot designation. However, a protocol, detailed operational account, and statistical analysis plan are not reported in the registry record. The record also does not explain how the planned sequence, outcome collection, or feasibility aims were implemented in practice.
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.
Overall Study
| Stage | Placebo Followed by T3 |
|---|---|
| STARTED | 51 |
| COMPLETED | 8 |
| NOT COMPLETED | 43 |
Reasons for not completing this period:
| Reason | Placebo Followed by T3 |
|---|---|
| Did not meet study criteria | 33 |
| Withdrawal by Subject | 3 |
| Adverse Event | 2 |
| Lost to Follow-up | 1 |
| Participation put on hold | 4 |
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.
Population: Each participant received placebo followed by 25 mcg of T3.
| Characteristic | Unit | Placebo Followed by T3 |
|---|---|---|
| Participants analysed | 51 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 51 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age, Continuous | years | 35.35 (SD 7.76) |
| Sex: Female, Male: Female | Participants | 50 |
| Sex: Female, Male: Male | Participants | 1 |
| Region of Enrollment: United States | participants | 51 |
6. Primary Endpoint
The registry lists the primary outcome as Visual Analogue Scale of Pain Intensity, measured over 12 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the Visual Analogue Scale of Pain Intensity. Participants rated pain on a scale ranging from 0, meaning no pain, to 10, meaning pain as bad as it can be. Ratings were described at baseline, during placebo, during T3 at 25 mcg, and during T3 at 50 mcg. The registry lists the measure as continuous and identifies the summary parameter as a mean with standard deviation, with a timeframe of 12 weeks.
A pain rating scale is used to turn a person’s reported experience into an ordered numerical measure that can be summarized and compared across assessment points. In general, continuous measures can be described by their average and by how dispersed individual observations are around that average. The mean gives a measure of the central level of reported pain, while the standard deviation describes variation among the observed ratings. Neither summary alone explains the full distribution or the experience of each participant.
Repeated ratings can describe how scores vary across the planned study periods. But the sequence matters: baseline, placebo, and T3 ratings were collected at different times, and the record describes a single-group sequence rather than randomized parallel groups. A change across measurements could therefore reflect treatment, time, period order, or other influences. Numerical means, standard deviations, changes, and uncertainty intervals for this endpoint are not reported in the registry record, so the magnitude and precision of any observed pattern cannot be assessed from the registry entries.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a primary pain-intensity measure and the planned sequence of assessments, but it does not report numerical outcome estimates or analyses. It lists one outcome measure and zero analyses. As a result, the record does not support a description of the direction or size of pain-rating changes, nor does it provide a confidence interval or other measure of statistical precision for the endpoint.
The design also limits what a change across assessment periods could establish. Participants moved from baseline to placebo and then to increasing T3 doses in a fixed order. Since the registry records a single group, no random allocation, and no separate concurrent control group, any difference between periods would combine treatment-period changes with possible time and sequence effects. A within-person sequence can be informative descriptively, but it does not supply the same counterfactual comparison as random assignment to treatment and control groups observed over the same period.
In general, an estimate describes the observed size and direction of a difference, while a confidence interval describes the range of values compatible with the data under the analysis assumptions. The interval helps readers assess precision; a point estimate without uncertainty can be misleading, especially in a pilot setting. Here, neither an endpoint estimate nor its uncertainty is reported in the registry record. Statistical significance, if it had been reported, would not by itself establish clinical importance; the record also does not define a threshold for a clinically important change.
The record’s stated purpose was to assess feasibility and the promise of a future prospective randomized controlled study. That purpose should not be conflated with demonstrating a treatment effect. A pilot can identify operational questions or motivate further research, but the posted registry entries do not give feasibility outcomes, such as recruitment or retention results, or details of obstacles and costs. Those results are not reported in the registry record.
Planning illustrations based on an observed effect are hypothetical design calculations, not observed power and not evidence of treatment benefit. The stated planning assumptions use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect set as a stated fraction of the observed effect. Such assumptions describe a possible future design, not the single-group sequence conducted in this study. Numerical planning estimates and the numerical observed effect are not reported in the registry record. The sponsor’s own analysis would take precedence if any recalculated result were discrepant, but no sponsor analysis is listed in the record.
Overall, the posted information establishes the endpoint, sequence, and broad design, but not the outcome pattern or its precision. It therefore allows a design-level interpretation, not a conclusion about the size, reliability, or clinical importance of pain changes during the study.
9. Statistical Methods Explained
The recorded outcome is continuous, summarized using a mean and standard deviation. The study has a single-group model and an ordered sequence of measurements. The registry record lists zero analyses, so it does not specify an analysis model, estimates, or inferential results. The concepts below explain how such data are commonly understood in general; they are not claims about an analysis performed in this trial.
What does a mean and standard deviation describe?
For a continuous outcome such as a pain rating, the mean is the arithmetic average of the observed ratings in the group or assessment period being described. The standard deviation describes how spread out the observations are around that mean. A smaller standard deviation indicates ratings are more clustered around the average, while a larger one indicates more variation. The mean and standard deviation are descriptive summaries; by themselves, they do not establish whether a difference between periods is attributable to treatment.
These summaries are most informative when considered alongside the number of observations contributing to each assessment and the distribution of scores. A mean can conceal differing patterns, such as a concentration near one end of the scale or a few unusually high ratings. The registry record does not report the period-specific means, standard deviations, or contributing observation counts. It therefore does not allow readers to inspect the distribution or judge the precision of these descriptive summaries.
Why does the sequence affect interpretation?
The recorded order places placebo before T3, with the T3 dose increasing between successive periods. Repeated measurement may reduce some between-person variability when describing how an individual’s ratings change. However, measurement order is linked to treatment period in this design. In general, time trends, expectations, carryover, changes in circumstances, or other period-related influences can contribute to a change between measurements. Without randomization or a concurrent comparison group, those influences cannot be separated from treatment effects using the design description alone.
A randomized parallel-group trial addresses a different question by assigning participants to separate groups and comparing outcomes over a common period. Random allocation is intended to make groups comparable on average, including on factors that are not directly measured. The registry record describes neither random allocation nor separate concurrent groups. The placebo phase in this study is part of the sequence, so it should not be interpreted as a randomized control arm.
What would an uncertainty interval add?
In general, a confidence interval accompanies an estimate and conveys its statistical uncertainty under the chosen model and assumptions. A narrower interval indicates greater precision; a wider interval indicates less precision. An interval also helps readers assess which effect sizes remain compatible with the observed data. It does not correct a biased design, remove confounding, or guarantee that the model assumptions are appropriate. No numerical interval or endpoint estimate is reported in the registry record, so precision cannot be evaluated for the primary outcome.
What do planning calculations mean?
Sample-size calculations are planning tools. They describe how many participants per arm a future study might require under specified assumptions about the effect to detect, significance level, allocation, and statistical method. The assumptions recorded for the planning illustration are a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect set to a stated fraction of the observed effect. This hypothetical two-arm plan is not the design recorded for the pilot, which is listed as single group.
These calculations are not “observed power.” Observed power is not a substitute for reporting an estimate and its uncertainty; planning calculations instead show how design choices relate to a target effect and precision. A planning estimate based on the observed effect can be unstable when the pilot estimate is uncertain. It should therefore be read as an illustration under assumptions, not as a forecast or evidence that a future study will achieve a particular result. Numerical planning estimates are not reported in the registry record.
What is not specified?
The registry record does not report a statistical analysis plan, a method for handling repeated measurements, an approach to missing observations, or an analysis population definition. It also does not report whether model assumptions were assessed or whether adjustments were planned. These details matter because they determine how repeated ratings are combined, which participants contribute to each estimate, and how uncertainty is calculated. Without them, no specific inferential method should be attributed to the trial.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one outcome measure, the Visual Analogue Scale of Pain Intensity, and zero analyses. It does not report a set of analyzed endpoints, hypothesis tests, or a statistical plan. The primary outcome description includes ratings at baseline, placebo, T3 at 25 mcg, and T3 at 50 mcg, but the record does not specify which period contrasts were intended for formal testing or how those contrasts would be ordered.
In general, multiplicity arises when several outcomes, time points, groups, or comparisons are tested. The more opportunities there are to find a statistically notable result, the more important it becomes to define the analysis plan and interpret results in that context. Adjustment procedures can control certain error rates, while a clearly prespecified primary comparison can help distinguish confirmatory questions from exploratory ones. The registry record does not report a multiplicity strategy, so none can be attributed to this study.
Missing-data handling is also not reported in the registry record. The enrollment entry does not establish how many participants contributed ratings at each period, whether any values were missing, or how missing ratings were treated. In general, missingness can affect both the estimated outcome and its uncertainty, particularly when the chance that a rating is missing relates to a participant’s experience or treatment period. The record does not report a method for addressing this possibility.
An analysis population is not reported in the registry record. It is therefore not possible to determine from the posted information whether the primary analysis was intended to include everyone enrolled, participants who began treatment, or participants with measurements at specified periods. These omissions limit reproducibility and make it difficult to evaluate whether any analysis, if conducted outside the registry record, followed a prespecified approach.
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 |
|---|---|---|---|
| Placebo Followed by T3 | 1 | 51 | 2.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Placebo Followed by T3 | 0 of 51 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Placebo Followed by T3 | 1 of 51 |
Most frequent serious adverse event terms
| Event term | Organ system | Placebo Followed by T3 |
|---|---|---|
| Tachycardia | Cardiac disorders | 1 of 51 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Placebo Followed by T3 |
|---|---|---|
| General | General disorders | 1 of 51 |
Serious events with the highest arm-level rate: tachycardia (2.0%).
The registry record lists 51 participants at risk for serious adverse events and 1 affected. It also lists 51 at risk for other adverse events and 1 affected, with 0 deaths. The top serious adverse event term is tachycardia, recorded as 2.0%. These entries describe the safety figures as posted; they do not provide a detailed case narrative, timing, severity grading beyond the serious-event classification, or an assessment of relationship to treatment.
The serious-event count and the listed top term should be read as separate registry entries. The record does not explain the relationship between the affected count and the term percentage, so no further reconciliation or event-level interpretation is warranted. The figures also do not establish how adverse events were collected across the placebo and T3 periods or whether exposure time differed by period.
In general, safety counts are descriptive. They can indicate what was recorded in a study, but interpretation depends on definitions, ascertainment, follow-up, and the completeness of reporting. A small pilot study may be unable to characterize uncommon events precisely; this is a general consideration, not a claim about an unreported event rate in this trial. The posted record does not support a causal conclusion about the listed events or a comparison with an external group.
12. What the Result Does, and Does Not, Mean
The record documents a pilot study of T3 in fibromyalgia with a single-group, ordered placebo-then-T3 sequence and repeated pain ratings. It also states that the study aimed to assess the feasibility and promise of a future prospective randomized controlled study. These features make the study relevant as an exploratory investigation of a research question and its potential future evaluation.
The record does not report numerical pain outcomes or analyses. It therefore cannot establish whether average pain ratings increased, decreased, or stayed similar across the study periods, how large any change was, or how precisely it was estimated. There is no reported confidence interval with which to judge statistical uncertainty, and the registry record does not define a clinically important change for the scale.
The study design also cannot provide a randomized treatment-versus-control estimate. Placebo came before T3, and the record lists no random allocation or separate concurrent control group. A difference across phases, if reported elsewhere, could reflect period order or time-related influences as well as treatment. The registry entries do not permit those possibilities to be separated.
The safety entries list serious and other adverse-event counts and identify tachycardia as the top serious term. They do not provide enough detail to establish causality or characterize the events by treatment period. The study’s completed status should not be mistaken for evidence that all enrolled participants completed every assessment or that the endpoint results are available in the registry record.
Thus, the posted information describes the study’s question, sequence, endpoint, and selected safety counts, but does not report an efficacy result. It does not show that T3 did or did not change pain, and it does not establish whether a future randomized study would confirm a particular effect. Its stated role is pilot and feasibility-oriented, with the numerical outcome findings and detailed methods not reported in the registry record.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the distinction between a pilot study’s research purpose and the evidence needed for a treatment-effect estimate. The stated aims include assessing whether a future prospective randomized controlled study is feasible and promising. That is different from a definitive randomized comparison designed to estimate a causal effect.
The design makes that distinction especially important. The registry records a single-group sequence, no random allocation, and no separate concurrent control group. Repeated pain ratings can describe variation across baseline, placebo, and T3 periods, but period order is tied to the intervention sequence. Statistical analysis cannot, on its own, remove the resulting ambiguity about whether changes are due to treatment or other time-dependent influences.
The record also illustrates why a named endpoint is not the same as a reported result. The pain scale, measurement points, summary type, and timeframe are specified, but the record lists zero analyses and gives no numerical outcome estimates. Without estimates and uncertainty, readers cannot judge effect size, precision, or whether a pattern would be compatible with no change or with a range of changes.
Finally, planning calculations and trial findings answer different questions. The recorded planning assumptions describe a hypothetical future two-arm design, while the pilot itself is listed as single group. Such calculations can help frame future design choices but are not evidence that an effect was established, nor are they observed power. Keeping these distinctions clear prevents exploratory design information from being mistaken for confirmatory clinical evidence.
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.
Several limitations follow directly from the registry description. The study is listed as single group, with allocation recorded as NA and masking recorded as NONE. The official title calls it double-blind, but the registry’s masking entry does not document blinding. The record does not explain this difference, so the study should not be characterized as masked on the basis of the title alone.
The intervention sequence is fixed: placebo precedes T3, and the T3 dose increases between periods. There is no concurrent randomized control group in the record. This means period, time, and treatment are difficult to disentangle, limiting causal interpretation of any phase-to-phase change. The placebo period is not a like-for-like randomized comparison with the T3 periods.
The registry identifies the primary endpoint and its scale but reports no numerical outcome results and zero analyses. Period-specific means, standard deviations, missing observations, and uncertainty estimates are not reported in the registry record. Consequently, the size, direction, and precision of outcome patterns cannot be assessed from these entries.
Additional protocol and analysis details are not reported in the registry record. These include eligibility criteria, the analysis population, the approach to repeated measurements, handling of missing data, and a statistical analysis plan. The record also does not report feasibility findings, costs, or obstacles, despite naming those topics as study aims. Enrollment and completed status alone do not establish how many participants completed each phase or contributed endpoint data.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study of T3 for the Treatment of Fibromyalgia — NCT00903877.
- Registry record last updated 2017-07-14; status last verified 2017-06.
- Results first posted 2017-07-14.
- 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
The registry record describes NCT00903877, “Study of T3 for the Treatment of Fibromyalgia,” as a completed pilot, non-randomized, single-group study sponsored by Stanford University. Enrollment is listed as 51. The study began in 2009-05, with primary completion in 2011-06.
The described sequence was placebo for 4 weeks, T3 at 25 mcg per day for 4 weeks, and T3 at 50 mcg per day for 4 more weeks. The primary endpoint was Visual Analogue Scale of Pain Intensity, rated from 0 to 10, with a 12 weeks timeframe. The outcome was specified as a continuous measure summarized by mean and standard deviation.
The registry lists one outcome measure and zero analyses. Numerical endpoint results and a statistical analysis plan are not reported in the registry record. Safety entries list 1 serious adverse event affected among 51 at risk, 1 other adverse event affected among 51 at risk, 0 deaths, and tachycardia as the top serious term at 2.0%. The stated study aim included assessing feasibility and promise for a future prospective randomized controlled study.