Efficacy of Intralesional Sodium Thiosulfate Versus Intralesional Saline for Dystrophic and Idiopathic Calcinosis Cutis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy of Intralesional Sodium Thiosulfate Versus Intralesional Saline for Dystrophic and Idiopathic Calcinosis Cutis (NCT03639779), a randomized phase 4 study. The primary outcome is Lesion Size.

2. Clinical Question

3. Trial Design

The registry describes a Phase 4, randomized, double-blind, parallel-group trial comparing intralesional sodium thiosulfate with intralesional saline for calcinosis cutis. Random allocation is intended to reduce systematic differences between treatment groups at assignment, while a parallel design means participants are assigned to one treatment group rather than crossing between treatments. The record identifies saline as the control and describes the study as placebo-controlled.

Double masking means the record classifies the trial as designed to keep treatment assignment concealed from relevant parties. Which individuals were masked, how masking was maintained, and whether it was assessed are not reported in the registry record. Randomization methods, allocation concealment procedures, and any stratification factors are also not reported in the registry record. Those details matter when evaluating how assignment was generated and whether knowledge of treatment could have influenced care or assessment.

Enrollment is listed as 5. The record gives a start date of 2018-11-02, a primary completion date of 2019-12-31, and a status of terminated. It does not state why the trial was terminated or whether termination occurred before planned recruitment or follow-up was complete. The listed completion date should not be interpreted as evidence that all intended observations were collected.

The primary endpoint is lesion size at 3 months, but the outcome entry notes one participant was lost to follow up. The record also says the primary outcome has several categories or time points and was not reduced to one comparison. These details constrain interpretation: the design is described, but a single numerical contrast between treatment groups is not available 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: The study had to be close early due to lack of support and time resulting in a lower number of participants than hoped for. 5 participants began the study, 1 was lost to follow-up. Each participant had 2 study lesions, each assigned to a different study arm.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: One participant was lost to follow up

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.

6. Primary Endpoint

The registry lists the primary outcome as Lesion Size, measured over 3 months.

Lesion size is the primary endpoint, measured in square centimeters. The record describes the endpoint as a mean with full-range dispersion at 3 months, and says lesion size is measured in square centimeters. This endpoint represents the size of the calcinosis cutis lesion or lesions assessed by the study. The record does not specify the measurement technique, who performed measurements, whether assessors were masked, or how multiple lesions within a participant were combined.

As a general statistical point, a continuous measurement such as lesion area can retain information about the degree of change rather than reducing each participant’s experience to a yes-or-no response. A mean describes the group’s average measurement, while the full range conveys the smallest and largest recorded values. These summaries can help describe the distribution, but a range is sensitive to extreme observations and does not by itself quantify uncertainty in the estimated mean or in a difference between groups.

The stated 3-month timeframe identifies when the primary measurement was intended to be assessed. A baseline lesion-size value and a follow-up value can support analysis of change, or a follow-up comparison can be adjusted for baseline; the registry record does not report which approach was planned or used. It also does not give the numerical lesion-size results. Consequently, the endpoint definition is available, but the magnitude and precision of the observed treatment contrast are not.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The trial is recorded as randomized and parallel-group. In a randomized trial, treatment assignment is determined by a chance-based process rather than by participant or clinician choice. As a general statistical principle, randomization can make measured and unmeasured characteristics comparable on average across groups, but it does not guarantee exact balance in a small study. The registry record does not report the random sequence method, allocation concealment, or any stratification or blocking procedures, so those features cannot be evaluated.

The record classifies masking as double. Masking is intended to limit the influence of treatment knowledge on behavior, co-interventions, and outcome assessment. The record does not identify which parties were masked or report the procedures used to preserve masking. Since the primary endpoint is lesion size, the identity and masking status of the assessor could be relevant; those details are not reported in the registry record. The record’s designation alone does not establish how well masking worked in practice.

The endpoint is a continuous measurement in square centimeters, summarized as a mean with full-range dispersion at 3 months. As a general statistical explanation, the mean is the arithmetic average and can be influenced by unusually large or small observations. The full range gives the observed minimum and maximum, but it does not show the density or shape of the data between those endpoints. It also does not provide a standard error or confidence interval. A mean and range can describe the sample, but they are not a substitute for a group contrast with an uncertainty estimate.

A treatment comparison for a continuous endpoint might be expressed as a difference in means, a difference in change from baseline, or a model-based contrast. These choices answer related but not identical questions and can produce different estimates, particularly when baseline measurements vary. The registry record does not state whether the intended comparison used follow-up values, change scores, baseline adjustment, or another method. It also does not report assumptions about the distribution of lesion-size measurements, handling of multiple lesions, or any transformations.

As a general statistical point, model assumptions matter because the method used to estimate uncertainty depends on how the data are distributed and how observations relate to one another. If variability is greater than a model allows, uncertainty can be understated; if the assumptions are unsuitable, the estimated effect and its interval may be unreliable. For lesion-size measurements, the record does not report a model, residual checks, robust methods, or other diagnostics. It is therefore not possible to evaluate the suitability of a particular inferential method from the registry record.

The record lists three outcome measures and zero analyses. Those entries do not provide a statistical analysis plan, result estimates, or evidence about which analyses were conducted outside the registry record. The primary-outcome note states that there are several categories or time points and that the outcome was not reduced to one comparison. A single summary effect should not be inferred from that note. The planned contrast, if any, and the rationale for selecting a particular time point or category are not reported in the registry record.

Multiplicity arises when multiple outcomes, time points, categories, or statistical comparisons are examined. As a general matter, more opportunities to find an apparently unusual result can increase the chance of a false positive if tests are interpreted without accounting for that multiplicity. Possible approaches include designating a primary comparison, adjusting inferential thresholds, or treating secondary findings as exploratory. The record does not report a multiplicity strategy. With multiple categories or time points noted and no single comparison available, the interpretation of any unreported comparison cannot be reconstructed.

The sample-size assumptions describe a planning illustration based on an observed effect rather than the trial’s own design. They specify a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. Such calculations are hypothetical design scenarios, not observed power and not evidence that the trial had a particular probability of detecting an effect. The numerical planning outputs and the observed effect used for them are not reported in the registry record. A planning calculation cannot compensate for the absence of an outcome estimate or its uncertainty.

As a general statistical point, confidence intervals are useful because they show how precisely a treatment contrast is estimated, under the chosen model and assumptions. A narrow interval indicates greater precision than a wide interval, although precision does not by itself determine clinical importance. The registry record does not report a confidence interval for lesion size or for a treatment contrast. Likewise, no p-value for a primary comparison is reported, so neither statistical significance nor its absence can be inferred.

Finally, the recorded enrollment and outcome handling affect the information available for analysis. One participant is noted as lost to follow up, but the record does not describe an intention-to-treat analysis, a per-protocol analysis, imputation, or sensitivity analyses. These are not interchangeable choices: each defines which participants or measurements contribute and relies on different assumptions. Without an analysis description and outcome values, the results cannot be independently reconstructed or checked.

10. Multiplicity, Missing Data and Analysis Populations

The record lists three outcome measures and zero analyses. It also notes that the primary outcome has several categories or time points and was not reduced to one comparison. No statistical analysis plan, hierarchy of outcomes, choice of primary time point, or adjustment for multiple testing is reported in the registry record. As a general statistical point, examining multiple outcomes or time points can make an isolated result harder to interpret unless the comparisons and their inferential approach are specified.

One participant was lost to follow up, according to the primary-outcome entry. The registry record does not identify the participant’s group, say whether the missing information concerns the primary endpoint, or explain the reason for loss. It does not report imputation, a complete-case analysis, sensitivity analyses, or another approach to missing data. Because conclusions can depend on how missing outcomes are handled, the absence of these details limits interpretation of any group summary.

The analysis population is not reported in the registry record. In particular, the record does not say whether analyses were intended to include all randomized participants, only those who received treatment, or a different set. These definitions affect which participants contribute to an estimate and should not be assumed from the randomized design alone. The record also does not specify whether any participants were excluded after randomization or how protocol deviations were handled.

These omissions do not establish that no analyses or missing-data procedures occurred; they mean that the registry record does not describe them. With no reported primary comparison, analysis population, or missing-data method, statistical significance, robustness, and the influence of the participant lost to follow up cannot be evaluated from the registry record.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The safety entries list the sodium thiosulfate group with 5 participants at risk, zero serious adverse events, zero other adverse events, and zero deaths. The saline group is also listed with 5 participants at risk, zero serious adverse events, zero other adverse events, and zero deaths. These are the recorded figures for the groups and should be read as counts in the registry record, not as proof that no adverse events could occur.

The record does not provide event definitions, the observation period for safety, the method of collection, or details about whether events were actively solicited. It also does not list serious adverse-event terms. Without those details, the scope of the zero counts is unclear: they do not convey the completeness of reporting or the ability to detect uncommon events.

Enrollment is listed as 5, while the safety entries list 5 at risk in each group. The registry record does not explain how these figures relate. They should not be reconciled by assumption. The safety counts also cannot be treated as a comparative estimate of risk without a clearly described denominator and follow-up period. No inference about treatment safety beyond the recorded counts is supported by these entries.

12. What the Result Does, and Does Not, Mean

The registry record establishes that a randomized, double-blind, parallel-group study was registered to compare intralesional sodium thiosulfate with saline for dystrophic and idiopathic calcinosis cutis. It identifies lesion size in square centimeters at 3 months as the primary endpoint and lists enrollment of 5. The record is marked terminated, and one participant is noted as lost to follow up.

What the record does not establish is the size or direction of any difference in lesion size between groups. It does not give numerical group means, a treatment-effect estimate, a confidence interval, or a p-value. The note that the outcome has several categories or time points and was not reduced to one comparison further means that a single treatment contrast cannot be read from the available record. No claim that either treatment performed better or worse is supported by the reported outcome information.

As a general statistical point, an absence of a reported comparison is not evidence that the treatments were equivalent. Equivalence requires a defined margin and an analysis capable of assessing whether the uncertainty around the difference lies within that margin. Those details and results are not reported in the registry record. Similarly, the absence of a reported p-value cannot be interpreted as a non-significant result.

The safety entries report zero serious adverse events, zero other adverse events, and zero deaths for each listed group, with 5 participants at risk in each. These counts describe what the registry record reports; they do not establish the absence of all harms or settle comparative safety. The record does not explain the relationship between the safety denominators and the enrollment entry.

Overall, the registry supports a description of the study’s question and design, but not a conclusion about efficacy, equivalence, or a precise safety difference. The terminated status, limited enrollment entry, missing outcome comparison, and unreported analysis details all constrain what can be inferred. Interpretation should remain limited to the design and counts explicitly recorded.

13. Why This Trial Matters Statistically

This trial is statistically notable because its registry entry describes a randomized, double-blind comparison but does not provide a numerical primary-outcome contrast. The design addresses a comparative question, yet the information needed to estimate the difference in lesion size and its uncertainty is not reported in the registry record. This distinction illustrates that a registered question and design do not, on their own, establish an answer to the question.

The enrollment entry is 5, and the trial is marked terminated. For a small study, estimates can be highly sensitive to individual observations, and uncertainty may be substantial. This is a general statistical consideration, not a calculated finding about this trial: the record contains no effect estimate or interval with which to quantify precision. The participant noted as lost to follow up adds a further reason to know how outcome data were handled, but that method is not reported.

The primary outcome note identifies several categories or time points and says the outcome was not reduced to one comparison. This matters because a reader needs to know which comparison represents the central question and how additional comparisons were treated. The record lists three outcome measures and zero analyses, and no multiplicity strategy or statistical analysis plan is reported.

The safety entries also illustrate why denominators and reporting context matter. They list 5 participants at risk in each group, while enrollment is listed as 5; the registry record does not explain the relationship. Zero event counts can be described, but their scope cannot be judged without information about ascertainment and follow-up.

These features make the study useful for examining the difference between trial design, outcome reporting, and inferential evidence. The record identifies the intended comparison and endpoint, while leaving the effect, precision, analysis population, and missing-data handling unresolved.

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 contains limited detail about the conduct of the trial. It does not report eligibility criteria beyond the target condition and forms of calcinosis cutis, participant characteristics, disease duration, or lesion characteristics. It also does not describe how lesions were selected or measured, how many lesions were assessed per participant, or how multiple lesion measurements were summarized.

The descriptions of sodium thiosulfate differ: the summary refers to 125mg/50ml, while the arm description refers to 50 ml vials of sodium thiosulfate (250mg/ml). The record does not clarify how these descriptions correspond to the administered preparation. It also does not report the injection schedule, treatment duration, or the amount delivered to each lesion. The saline arm is described as 0.9% sodium chloride, but administration details are not reported.

The trial is marked terminated, but the reason for termination and the intended enrollment are not reported in the registry record. Enrollment is listed as 5, while the safety entries list 5 participants at risk in each arm; the relationship between these entries is not explained. The primary outcome note records one participant lost to follow up, without identifying the group, missing measurements, or handling method.

Most importantly for statistical interpretation, numerical lesion-size results and an inferential comparison are not reported. The record does not state the analysis method, analysis population, confidence intervals, or statistical tests. It also does not specify how multiple categories or time points were handled, despite noting that the primary outcome was not reduced to one comparison. These limitations prevent assessment of effect magnitude, precision, and robustness from the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Efficacy of Intralesional Sodium Thiosulfate Versus Intralesional Saline for Dystrophic and Idiopathic Calcinosis Cutis — NCT03639779.
• Registry record last updated 2021-07-01; status last verified 2021-06.
• Results first posted 2021-07-01.
• 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.

18. Record Summary

NCT03639779 is a Phase 4, randomized, double-blind, parallel-group trial sponsored by the University of Central Florida. It compares intralesional sodium thiosulfate with intralesional saline for dystrophic and idiopathic calcinosis cutis. The registry lists enrollment of 5, a start date of 2018-11-02, a primary completion date of 2019-12-31, and a status of terminated.

The primary endpoint is lesion size in square centimeters, summarized as a mean with full-range dispersion at 3 months. The outcome entry notes one participant lost to follow up and says the primary outcome has several categories or time points, not reduced to one comparison. Numerical group results and a treatment-effect estimate are not reported in the registry record. Safety entries list zero serious adverse events, zero other adverse events, and zero deaths in each group, with 5 at risk in each group; the relationship of these counts to listed enrollment is not explained.