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 Visceral Manipulation in Patients With Chronic Low Back Pain (NCT03101020), a randomized na study. The primary outcome is Low Back Pain After 6 Weeks of Intervention.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03101020 |
| Phase | NA |
| Condition | Chronic Low Back Pain |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 20 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Sorocaba |
| Results posted | Yes |
2. Clinical Question
Population
The primary-outcome population is described as 20 participants with low back pain and visceral dysfunction. The condition listed for the trial is chronic low back pain. The record does not provide further eligibility criteria or participant characteristics, so the population cannot be described more narrowly from the registry record.
Intervention
The experimental group is described as receiving standard care physiotherapy plus active visceral manipulation. The registry summary presents visceral manipulation as a manual therapy intended to address mechanical, vascular and neurological dysfunctions of the viscera. It proposes that changes in visceral mobility might relate to low back pain, but this rationale is a hypothesis rather than an outcome finding.
Comparator
The control group is described as receiving standard care physiotherapy plus placebo visceral manipulation. The registry record does not describe the placebo procedure or give detail about the physiotherapy protocol. The comparison therefore concerns the addition of active rather than placebo visceral manipulation to the stated standard care.
Primary question
The stated primary outcome is low back pain after 6 weeks of intervention, measured in units on a scale using the mean and standard deviation. The registry describes an 11-point Numeric Pain Rating Scale, anchored at no pain and unbearable pain. The central question is whether pain scores at that follow-up differ between the two described groups. A single between-group result is not reported in the registry record: the outcome has several categories or time points and was not reduced to one comparison. Therefore the direction, size and precision of any group difference cannot be determined from the posted results.
3. Trial Design
The registry describes a randomized, single-masked, parallel-group trial of visceral manipulation in people with chronic low back pain. The record lists enrollment as 20 and gives the sponsor as the University of Sorocaba. The study status is completed. The recorded start date is 2017-06-01, and primary completion is recorded as 2017-07-06. These dates describe the registry record and do not, by themselves, explain when each participant received treatment or completed follow-up.
The two arms are called Experimental Group and Control Group. The experimental group is described as receiving standard care physiotherapy plus active visceral manipulation; the control group is described as receiving standard care physiotherapy plus placebo visceral manipulation. The allocation is randomized and the model is parallel, meaning the record describes participants assigned to one group rather than a crossover between treatments. The registry labels masking as single, but does not report who was masked or how masking was maintained. Details of the allocation procedure, concealment, treatment schedule and placebo procedure are not reported in the registry record.
The primary outcome is low back pain after 6 weeks of intervention. The registry also lists secondary outcomes for low back mobility using the Schober Test, disability due to low back pain, and functional activity, each described after 6 weeks of intervention. The record lists four outcome measures in total, but does not report a single numerical result for the primary outcome. It records zero analyses. The phase entry is NA; a development phase is not otherwise described.
The posted information establishes the planned comparison and broad outcome framework, but not the full protocol or analysis plan. In particular, eligibility rules beyond the stated population, participant flow, adherence, deviations from assigned treatment and the identity of the masked party 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: There were no events that occur after participant enrollment, but prior to assignment of participants to a group
Overall Study
| Stage | Experimental Group | Control Group |
|---|---|---|
| STARTED | 10 | 10 |
| COMPLETED | 9 | 7 |
| NOT COMPLETED | 1 | 3 |
Reasons for not completing this period:
| Reason | Experimental Group | Control Group |
|---|---|---|
| Lack of time to participate | 1 | 0 |
| Ran over by a car | 0 | 1 |
| Withdrawal by Subject | 0 | 2 |
Analysis population for the primary outcome, as defined in the registry: 20 participants with low back pain and visceral dysfunction
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: 20 participants with chronic low back pain and visceral dysfunction
| Characteristic | Unit | Experimental Group | Control Group | Total |
|---|---|---|---|---|
| Participants analysed | 10 | 10 | 20 | |
| Age, Continuous | years | 41.5 (SD 10.39) | 40.5 (SD 12.12) | 40.5 (SD 9.55) |
| Sex: Female, Male: Female | Participants | 9 | 10 | 19 |
| Sex: Female, Male: Male | Participants | 1 | 0 | 1 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: Brazil | participants | 10 | 10 | 20 |
| Visceral dysfunction | Participants | 10 | 10 | 20 |
6. Primary Endpoint
The registry lists the primary outcome as Low Back Pain After 6 Weeks of Intervention, measured over 6 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 low back pain after 6 weeks of intervention. It is assessed using an 11-point Numeric Pain Rating Scale (NPRS), described as running from 0 for no pain to 10 for unbearable pain. The registry expresses the outcome in units on a scale and specifies the mean as the summary measure, with standard deviation as the dispersion measure. This is a continuous outcome: the recorded value can vary across the scale rather than being limited to an event/no-event category.
Pain ratings are used to capture participants’ reported pain intensity at a specified follow-up. A group mean can describe the average reported score, while the standard deviation describes how much individual scores vary around that average. Neither statistic alone establishes how groups compare. A treatment comparison would ordinarily require a clearly defined between-group estimate, with its uncertainty, and an account of the analysis used. Those numerical results are not reported in the registry record.
The endpoint description names a scale and follow-up, but it does not explain how repeated assessments, if any, were handled or whether the primary analysis used an endpoint score, change from baseline, or another summary. Because the registry states that the primary outcome has several categories or time points and was not reduced to one comparison, a single primary contrast cannot be interpreted from this record. The scale description gives context for what the outcome is intended to measure; it does not provide evidence about the observed level of pain or a difference between groups.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies a primary outcome and the groups intended for comparison, but it does not report a single numerical comparison for low back pain after 6 weeks. The record specifically indicates that the primary outcome has several categories or time points and was not reduced to one comparison. No group means, standard deviations, between-group estimate, confidence interval or p-value for a primary comparison are reported in the registry record. Consequently, the direction and size of an observed difference, and the precision with which it was estimated, cannot be assessed from the posted results.
This absence of a single reported comparison is important for interpretation. A trial’s design and outcome definition describe what investigators intended to study; they are not substitutes for outcome results. The registry lists random allocation and two parallel groups, but does not provide a numerical result showing how pain scores compared. It would therefore be inappropriate to describe the intervention as beneficial, ineffective or equivalent to the comparator on the basis of this record.
The registry lists four outcome measures and names secondary outcomes concerning low back mobility, disability and functional activity after 6 weeks. It does not report numerical results for those outcomes in the record. The presence of outcome titles cannot establish whether measurements were collected, what values were observed, or whether groups differed. The entry of zero analyses reinforces that no analysis output is available in the posted registry results; it does not establish why results are absent or whether analyses were conducted elsewhere.
Precision cannot be judged without an effect estimate and a measure of uncertainty, such as a confidence interval. In general, a confidence interval communicates a range of effect values compatible with the data and analysis assumptions. A narrow interval indicates greater statistical precision than a wide interval, although precision alone does not establish importance. No such interval is reported for the primary outcome.
The record includes a planning illustration based on an observed effect and specified assumptions, but no resulting sample-size values are included in the available trial details. Such planning values, when reported, would not be observed power or evidence that a result was obtained. Since the observed primary effect is not reported, the planning illustration cannot fill the gap in the outcome evidence. Interpretation must remain limited to the documented design, outcome definitions and the absence of a single reported primary comparison.
9. Statistical Methods Explained
The registry describes randomized allocation, a parallel-group model and single masking. These terms identify broad design features, but they do not fully specify how the trial was conducted or analysed. Randomization is intended to allocate participants by chance, which can reduce systematic differences between groups at baseline. It does not guarantee that groups will be similar in every characteristic, particularly in a small trial. The record does not describe the sequence-generation or allocation-concealment procedures, so those methods cannot be evaluated.
What does a mean and standard deviation describe?
General statistical explanation: For a continuous outcome such as a pain-scale score, the mean is an average that describes the group’s central value. The standard deviation describes the spread of individual values around that average. They answer different questions: a mean does not show how varied the scores are, and a standard deviation does not show the difference between treatment groups. A complete comparison usually reports group summaries together with an estimate of the between-group effect and its uncertainty.
The registry identifies the primary outcome as a mean, with standard deviation, on the Numeric Pain Rating Scale after 6 weeks. However, the posted results do not provide the means or standard deviations needed to describe the observed scores. Nor is a single comparison reported. The record notes that the outcome has several categories or time points and was not reduced to one comparison. Without knowing which result was intended as the primary contrast, readers cannot select or reconstruct a unique estimate from the registry entry.
Why does a confidence interval matter?
General statistical explanation: A confidence interval expresses uncertainty around an estimated effect under the assumptions of the analysis. Its width conveys statistical precision: less uncertainty corresponds to a narrower interval, while more uncertainty corresponds to a wider interval. The interval also helps readers assess which effect sizes remain compatible with the data. It is not a guarantee that the true effect lies within the particular interval, and it does not by itself determine whether an effect is important.
No confidence interval for the primary comparison is reported in the registry record. A p-value is also not reported. A p-value, in general, describes how compatible the observed data are with a specified null hypothesis under a statistical model; it does not quantify the size or clinical importance of an effect. In the absence of the estimate and uncertainty, neither statistical significance nor precision can be assessed from the posted primary results.
What can the sample-size assumptions tell readers?
The registry describes a planning illustration based on the observed effect, a two-sided significance level of 0.05, equal allocation between two arms and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. These are planning assumptions, not a report of the trial’s own design justification. The record does not report a sample-size justification for the trial, and the numerical outputs of the planning illustration are not included in the available information. The observed effect itself is also not reported as a single primary comparison.
General statistical explanation: A sample-size calculation estimates the number of participants needed to target a chosen level of power for a specified effect and set of assumptions. It depends on the chosen effect, outcome variability, significance level, allocation and analysis method. Changing the effect size targeted changes the planning requirement. Such calculations are not a measure of the power actually achieved after a study, and a post hoc calculation cannot replace an estimate with a confidence interval. Any planning illustration should therefore be read as conditional on its stated assumptions, not as an observed trial result.
Why can over-dispersion matter?
General statistical explanation: Over-dispersion occurs when observed variability is greater than a statistical model assumes. If a model understates variability, standard errors may be too small and uncertainty may appear less than it is. The registry identifies a continuous outcome summarized by a mean and standard deviation, but does not report a model, residual diagnostics or an over-dispersion assessment. It would be speculative to claim that over-dispersion was present or that any particular adjustment was used.
The record lists zero analyses and does not supply an analysis specification for the primary endpoint. It does not state whether comparisons were adjusted for baseline scores, how missing outcome observations were handled, or which analysis population was used. No recalculated estimate can be produced from the registry information because the required group summaries and a single comparison are absent. The sponsor’s own analysis cannot be compared with a recalculation because no sponsor analysis result is reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary outcome and three named secondary outcomes: low back mobility using the Schober Test, disability due to low back pain, and functional activity, all after 6 weeks of intervention. It also notes that the primary outcome has several categories or time points and was not reduced to one comparison. This makes the intended primary contrast unclear in the posted results. No multiplicity adjustment or plan for interpreting several outcomes or time points is reported in the registry record.
General statistical explanation: When several outcomes, time points or comparisons are examined, the chance of finding at least one apparently unusual result can increase if each is interpreted separately. A prespecified hierarchy or multiplicity adjustment can help define how evidence across comparisons should be interpreted. The record does not say whether such a strategy was planned or used. This uncertainty does not establish that the analysis was inappropriate; it means the approach cannot be evaluated from the registry entry.
Missing-data methods are not reported in the registry record. The entry does not state how many outcome observations were missing, why any were missing, whether participants were included according to randomized assignment, or whether another analysis population was used. The analysis population and handling of protocol deviations are likewise not described. These details matter because estimates can depend on which participants’ measurements are included and how unavailable measurements are addressed. No assumptions about these choices should be made from the outcome titles or trial status alone.
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 |
|---|---|---|---|
| Experimental Group | 0 | 10 | 0.0% |
| Control Group | 0 | 10 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Experimental Group | 0 of 10 |
| Control Group | 0 of 10 |
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 |
|---|---|
| Experimental Group | 10 of 10 |
| Control Group | 10 of 10 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Experimental Group | Control Group |
|---|---|---|---|
| Muscle soreness | Musculoskeletal and connective tissue disorders | 10 of 10 | 10 of 10 |
| Abdominal discomfort | Gastrointestinal disorders | 3 of 10 | 2 of 10 |
| Back Pain | Musculoskeletal and connective tissue disorders | 1 of 10 | 1 of 10 |
The registry lists serious adverse events for the Experimental Group as 0 affected among 10 at risk, and for the Control Group as 0 affected among 10 at risk. Deaths are listed as 0 in each group. The record lists no top serious-event terms. These entries describe the serious-event figures recorded in the registry; they do not establish that all possible harms were comprehensively assessed or reported.
For other adverse events, the registry lists 10 affected among 10 at risk in each group. The record does not define the event categories, explain whether the affected figure counts participants with one or more events, or give event descriptions and severity. Therefore the entry should not be interpreted as an event count or as evidence that every event had the same nature or importance. It also does not clarify the collection period or how events were solicited.
General statistical explanation: A zero count of recorded serious events does not show that the underlying risk is zero. Safety estimates are influenced by the amount of observation and the completeness of event ascertainment. Here, the registry provides only the listed group figures and does not report methods or detailed event narratives. The safety record can be described as reporting no serious adverse events or deaths in either group, while recognizing that the available information is limited and does not support broader conclusions about safety.
12. What the Result Does, and Does Not, Mean
The record establishes that investigators registered a randomized, single-masked, parallel-group comparison of active visceral manipulation plus standard care physiotherapy against placebo visceral manipulation plus standard care physiotherapy. It identifies chronic low back pain as the condition and low back pain after 6 weeks as the primary outcome. It also provides a scale description and names secondary outcomes. These details clarify the question the study was designed to address.
The posted results do not establish what happened to pain scores in either group or whether the groups differed. The registry does not report a single primary comparison, group means, standard deviations, an effect estimate, a confidence interval or a p-value. It would be inaccurate to infer benefit, lack of benefit, equivalence or harm from the missing primary result. The absence of reported results is a limitation of what can be concluded from this record, not itself evidence about the treatment effect.
The record’s explanation of a possible relationship between visceral mobility and low back pain describes the investigators’ rationale and hypothesis. It does not demonstrate that visceral dysfunction causes pain, that manipulation changes the proposed mechanisms, or that any such change affects symptoms. A mechanistic explanation is distinct from a measured clinical outcome, and the registry does not report mechanistic results.
The safety figures report zero serious adverse events and zero deaths in each listed group, alongside other adverse events recorded in both groups. The descriptions and ascertainment details are limited. These entries should be interpreted as registry-reported counts, not as a complete characterization of all possible adverse effects.
Overall, the registry is informative about the planned comparison and intended outcome measurement, but the available results do not permit an estimate of the primary treatment contrast. Further interpretation would require a clearly defined outcome comparison with numerical results and an account of the analysis and missing data.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the difference between a registered clinical question and an interpretable treatment-effect estimate. The design identifies the intended groups, outcome and follow-up, but a statistical conclusion about the primary question requires a reported comparison. Without a single primary result, readers cannot assess the observed direction or size of an effect, its precision, or how compatible the data are with different possible effects.
The record also shows why specifying outcomes and time points matters. It names several outcomes and states that the primary outcome has several categories or time points, but does not reduce them to a single comparison. When multiple measurements are possible, a clear analysis target helps readers understand which result answers the primary question and how other findings should be interpreted. Without that information, selective emphasis among potential results cannot be assessed, though the record does not establish that selective reporting occurred.
In general, a numerical estimate accompanied by uncertainty is more informative than a significance label alone. The estimate describes the scale and direction of a comparison; its uncertainty conveys how precisely it is known. Here, neither is reported for the primary comparison, so the clinical interpretation remains unresolved in this registry record. The listed planning assumptions cannot substitute for outcome results, and planning illustrations should not be mistaken for observed power.
The trial’s safety entries also require careful statistical reading. Zero reported serious events and deaths are descriptive findings in the registry, while the record gives limited detail about how adverse events were defined and collected. Statistical interpretation depends not only on counts but also on clear denominators, ascertainment and reporting. These considerations make the entry useful for understanding what was registered, while limiting the strength of conclusions that can be drawn from the posted results.
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 registry record does not provide a single primary-outcome comparison, despite naming low back pain after 6 weeks as the primary outcome. The reason recorded is that the outcome has several categories or time points and was not reduced to one comparison. As a result, the group-level outcome values, effect estimate, uncertainty and statistical test cannot be evaluated. The record lists zero analyses.
Several design details that would help assess risk of bias are not reported in the registry record. These include the randomization procedure, allocation concealment, who was masked, the placebo procedure and details of the standard care physiotherapy. The record does not provide eligibility criteria beyond the described population, baseline characteristics, participant flow, adherence or treatment deviations. It therefore does not support a detailed assessment of comparability or implementation.
The statistical plan is also not reported. There is no stated approach to baseline adjustment, outcome distributions, repeated measurements, multiplicity, missing data or analysis populations. The registry’s planning-illustration assumptions are not a substitute for the trial’s own design justification; the latter is not reported. Numerical planning outputs are not included among the registry entries.
Safety information is limited to group-level serious and other adverse-event figures. Event definitions, descriptions, ascertainment methods and observation periods are not reported. The other-adverse-event entries cannot be interpreted as a count of individual events based on the registry information. These omissions constrain both the assessment of safety reporting and the interpretation of the recorded figures.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Visceral Manipulation in Patients With Chronic Low Back Pain — NCT03101020.
- Registry record last updated 2020-08-19; status last verified 2020-08.
- Results first posted 2019-07-23.
- 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
NCT03101020 is a completed, randomized, single-masked, parallel-group trial titled “Visceral Manipulation in Patients With Chronic Low Back Pain.” The registry lists enrollment as 20 and identifies the University of Sorocaba as sponsor. It describes active visceral manipulation plus standard care physiotherapy compared with placebo visceral manipulation plus standard care physiotherapy.
The primary outcome is low back pain after 6 weeks, measured on an 11-point Numeric Pain Rating Scale and summarized as a mean with standard deviation. Secondary outcomes concern mobility, disability and functional activity. The registry does not report a single primary comparison or numerical primary results; it records zero analyses. Serious adverse events and deaths are listed as zero in both groups, while other adverse events are listed for both groups. Details needed to interpret outcome analyses, missing data and event ascertainment are not reported in the registry record.