Effect Of Ophiochepalus Striatus Extract On Serum IGF-1 And IL-6 Levels In Elderly Patients With Sarcopenia: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effect Of Ophiochepalus Striatus Extract On Serum IGF-1 And IL-6 Levels In Elderly Patients With Sarcopenia (NCT05869383), a randomized phase 2, phase 3 study. The primary outcome is IGF-1 Levels.

2. Clinical Question

3. Trial Design

The registry describes a randomized, double-masked, parallel-group trial, classified as Phase 2 and Phase 3. The sponsor is Universitas Sriwijaya. The condition and topic labels include sarcopenia, geriatric patients, muscle mass, muscle strength, and physical performance. The planned enrollment is 80 participants. The status is completed, with a listed start date of 2023-05-01 and primary completion date of 2023-09-30.

The intervention arm received Ophiochepalus striatus extract at 2x5 grams a day for 14 days. The control arm received placebo at 2x5 grams a day for 14 days. Although the design is described as double-masked, the registry record does not report which people were masked or how masking was maintained. It also does not describe the randomization sequence or allocation concealment.

The primary outcome is IGF-1 levels, measured in serum at 2 weeks. The posted summaries give a mean and standard deviation for each arm. The outcome summary lists 38 participants for placebo and 40 for the extract arm. These counts describe the posted endpoint summaries; the registry record does not explain the relationship between these counts and the planned enrollment, or identify an analysis population.

The registry summary also states questions about IL-6, SARC-F score, muscle mass, muscle strength, and physical performance. However, no secondary outcome results are posted, and no analyses are listed. The trial’s original sample-size justification, prespecified analysis plan, and details about participant flow are not reported in the registry record. Consequently, the posted results support a description of the IGF-1 summary and its uncertainty, but do not answer the additional questions listed in the study summary.

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

Reasons for not completing this period:

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 IGF-1 Levels, measured over 2 weeks.

The primary endpoint is serum IGF-1 at 2 weeks, expressed in ng/dl. The registry describes IGF-1 as a serum level measured using Cloud-Clone Corp® ELISA reagent with serial numbers 6854322BA3. The posted outcome is summarized as a mean and standard deviation in each treatment arm, with a mean difference and confidence interval for the comparison.

This endpoint is used because the registry identifies IGF-1 levels as the primary measure and asks whether the extract affects those levels over the intervention period. A continuous measure can be summarized by its average as well as the spread of individual measurements around that average. Comparing arm means offers a compact estimate of the difference in average measured levels, while the confidence interval indicates how uncertain that estimated difference is.

The registry summary also raises questions about other outcomes, including IL-6, SARC-F score, muscle mass, muscle strength, and physical performance. Those are not the posted primary endpoint result. No secondary outcome findings are reported in the registry record, so the IGF-1 comparison should not be treated as a result for those other measures.

7. Results Posted in the Registry

• Ophiochepalus Striatus Extract: mean 77.08 versus 78.92 on control; difference -1.84 (95% CI -11.30 to 7.62), standardized effect d = -0.09; z-test p = 0.703.

8. Statistical Interpretation

9. Statistical Methods Explained

The registry reports a continuous primary outcome: serum IGF-1 at 2 weeks, in ng/dl. For a continuous measure, the mean describes the average recorded value in an arm, while the standard deviation describes the spread of individual values around that mean. These are descriptive summaries. They do not, by themselves, show the range of individual participant values or how those values are distributed.

The placebo arm had a mean of 78.92 and standard deviation of 21.7, based on 38 participants in the posted summary. The extract arm had a mean of 77.08 and standard deviation of 20.9, based on 40 participants. The comparison is presented as extract versus placebo, with a mean difference of -1.84 ng/dl. The negative sign indicates that the extract-arm mean is lower than the placebo-arm mean in this reported comparison. The registry does not specify whether the estimate is adjusted for baseline measurements or other covariates.

What does the confidence interval describe?

A confidence interval gives a range of values compatible with the observed data under the method used to calculate it. It represents uncertainty in an estimated group difference, not a range containing a stated proportion of individual participants. The reported interval for the mean difference is -11.3 to 7.623 ng/dl. Because it includes zero, the interval is compatible with no average difference as well as differences in either direction. The interval’s width conveys that the estimate is not highly precise.

The confidence interval’s interpretation depends on the statistical procedure and its assumptions. The registry record does not report the procedure used to construct this interval, whether the analysis was adjusted, or the assumptions checked. The comparison information includes a pooled standard deviation of 21.29 and a standardized difference of -0.086. These are additional descriptions of the observed contrast and variability; the record does not explain the method used for the standardized estimate. They do not replace the original scale of ng/dl, which is the direct scale for interpreting the endpoint.

How should the p-value be read?

The posted unadjusted p-value is 0.703. In general, a p-value describes how unusual data at least as incompatible with a specified statistical null hypothesis would be if that hypothesis and the test assumptions held. It is not the probability that the null hypothesis is true, nor does it measure the probability that the result occurred by chance. The registry does not identify the test that produced this value or state whether there were prespecified covariates. As the value is explicitly unadjusted, it should not be mistaken for a multiplicity-adjusted result.

The estimate, interval, and p-value answer related but distinct questions. The estimate gives the direction and scale of the observed contrast. The interval expresses uncertainty about that contrast. The p-value summarizes evidence against a statistical null under a test. Considered together, the posted summaries do not indicate a precise difference between arm means. They also do not show that the means are identical or exclude all potentially relevant differences.

Why does over-dispersion matter?

General: over-dispersion occurs when the variation in observed data is greater than a statistical model assumes. When a model understates variability, uncertainty estimates can be too small and tests can appear more conclusive than warranted. This concept is especially relevant to methods that impose a particular distributional model. The endpoint is summarized as a continuous measure with means and standard deviations, but the registry record does not report a model, diagnostic checks, or an assessment of over-dispersion. It is therefore not possible to say whether this issue applied to the analysis.

What does the sample-size illustration represent?

The planning illustration is based on the observed effect, with estimates for planning around 100% of that observed effect, 75% of the observed effect, and 50% of the observed effect. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. These are planning assumptions for the illustration, not documented assumptions from the trial’s original design. The original sample-size justification and design assumptions are not reported in the registry record.

The illustration gives participants per arm for the continuous-outcome comparison. Its estimates should not be read as the number needed to establish a clinical benefit, and they do not indicate the probability that the trial result is correct. Since the observed difference is small relative to its uncertainty, planning estimates based on fractions of that observed effect can require many participants. Such estimates are sensitive to the effect chosen for planning and to the stated statistical assumptions.

More broadly, a complete assessment of the analysis would require details that are not reported in the registry record: the prespecified analysis plan, the exact statistical test or model, the handling of baseline values, the analysis population, missing-data procedures, and any planned adjustment for multiple outcomes. The registry’s posted numbers allow the reported continuous endpoint comparison to be described, but they do not permit reconstruction of these methodological details.

10. Confidence Intervals and Precision

The mean difference in serum IGF-1 was -1.84 ng/dl for extract compared with placebo. Its confidence interval, from -11.3 to 7.623 ng/dl, spans negative and positive values and includes zero. This indicates substantial uncertainty about the direction and size of the underlying difference. The interval is not a prediction range for individual participants; it describes uncertainty around the estimated difference in arm means under the method used.

The interval allows for the possibility that the extract-arm mean was lower than the placebo-arm mean, but it also allows for a higher extract-arm mean. Its breadth means that the estimate does not pin down a narrow range of plausible differences. The posted standard deviations, 21.7 for placebo and 20.9 for extract, describe variation among measurements within each arm; they are not uncertainty intervals for the arm means.

The unadjusted p-value is 0.703. The interval and p-value are consistent with a comparison that does not distinguish the arm means clearly. They should not be interpreted as proof that the means are equal. Nor does the interval establish which possible differences would matter in practice: a clinically meaningful threshold is not reported in the registry record.

Precision is also affected by the available endpoint counts and by analysis choices. The reported summaries include 38 placebo participants and 40 extract participants. The registry record does not explain missing observations, the analysis population, baseline adjustment, or the interval-calculation method. Without those details, the reported interval can be described, but its construction and sensitivity to alternative choices cannot be independently assessed from the registry record.

11. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size estimates are planning illustrations for a continuous outcome, expressed as participants per arm. They are not total event counts. The calculations are based on the observed effect, use a two-sided significance level of 0.05, assume equal allocation between the two arms, and use a normal approximation. The planning effect is varied across 100% of the observed effect, 75% of the observed effect, and 50% of the observed effect. These assumptions describe the illustration; the trial’s own original design assumptions and sample-size justification are not reported in the registry record.

The 80% power column gives the number of participants per arm that the illustration estimates would be needed to detect the chosen effect under its stated assumptions, with an 80% chance of detecting it if that effect were the true one and the assumptions held. The 90% power column expresses the same planning idea with a higher target chance of detection. These figures are not observed power and do not describe the probability that the posted result is true.

For planning around 100% of the observed effect, the estimate is 2,103 participants per arm for 80% power and 2,815 for 90% power. For planning around 75% of the observed effect, it is 3,738 participants per arm for 80% power and 5,004 for 90% power. For planning around 50% of the observed effect, it is 8,410 participants per arm for 80% power and 11,258 for 90% power. The illustration requires more participants when the effect to be detected is smaller. These figures depend on the observed effect and the assumptions used, and should be read as planning scenarios rather than as a reassessment of the trial’s completed enrollment.

12. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = -1.840; pooled standard deviation σ = 21.293.
2. n = 2 × (1.96 + 0.842)² × 21.293² / -1.840² = 2,102.3, rounded up to 2,103 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- -1.84                      # observed difference in means
sigma <- 21.2932284763811                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(5869383)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 2,103 (80% power), 2,815 (90% power)
 75% of observed effect: n per arm = 3,738 (80% power), 5,004 (90% power)
 50% of observed effect: n per arm = 8,410 (80% power), 11,258 (90% power)
power.t.test: 2103.2 
Simulated power at n = 2,103 per arm: 0.798 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

13. Multiplicity, Missing Data and Analysis Populations

The registry summary identifies several research questions: serum IGF-1, serum IL-6, SARC-F score, muscle mass, muscle strength, and physical performance. The primary outcome result posted is IGF-1 at 2 weeks. No secondary outcome results are posted, and the registry lists no analyses. The record does not report whether the other outcomes were prespecified as secondary endpoints, how they were measured, or whether they were analyzed.

When a study examines multiple outcomes or makes multiple statistical comparisons, the chance of obtaining at least one apparently notable result can increase. Statistical approaches can account for multiplicity, depending on the design and analysis plan. The registry record does not report a multiplicity strategy or explain how the primary and other questions were prioritized in the analysis. The posted p-value is unadjusted, so it should not be described as adjusted for other comparisons.

The registry record also does not report the analysis population or how participants were handled if they did not complete the intervention or lacked an endpoint measurement. It lists 38 participants in the placebo outcome summary and 40 in the extract outcome summary, but does not explain whether these are all randomized participants, participants with available measurements, or another analysis set. The record does not describe missing-data assumptions, imputation, exclusions, or sensitivity analyses.

Baseline IGF-1 summaries, baseline-adjusted comparisons, protocol deviations, and participant-flow details are not reported in the registry record. These omissions matter because they limit the ability to assess whether the groups were compared as planned, how incomplete observations affected the estimate, and whether analytic decisions could have changed the result. The available record supports interpretation of the posted endpoint summaries, but not a full audit of multiplicity, missing-data handling, or analysis-population choices.

14. 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.

Most frequent non-serious adverse event terms

The serious adverse event summaries list 0 affected participants among 38 at risk in the placebo arm and 0 among 40 at risk in the extract arm. Deaths are listed as 0 in both arms. The record lists 6 participants with other adverse events among 38 at risk in the placebo arm and 8 among 40 at risk in the extract arm. No serious adverse event terms are listed.

These figures are counts from the registry record. They do not describe event severity beyond the serious-versus-other categorization, event timing, duration, or causal attribution. The record does not report definitions used for adverse events, whether events were actively solicited, or whether the counts represent people with at least one event or a count of event occurrences. The figures should therefore be read according to the registry’s participant-count presentation, without assuming details that are not reported.

A finding of zero listed serious adverse events or deaths is not proof that such events cannot occur. The trial’s planned enrollment was 80, and the endpoint summaries list 38 and 40 participants in the two arms. These safety counts describe what the registry reports for this trial; they are not, by themselves, a comprehensive assessment of safety.

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

The posted primary result is a comparison of mean serum IGF-1 levels at 2 weeks. The placebo mean was 78.92 ng/dl and the extract mean was 77.08 ng/dl. The mean difference was -1.84 ng/dl, with a confidence interval from -11.3 to 7.623 ng/dl and an unadjusted p-value of 0.703. The interval spans zero and values in both directions, so the result does not precisely establish the direction or size of an average difference.

This result does not show that the arm means are exactly equal. The estimate is uncertain, and the confidence interval remains compatible with a range of differences. The registry record does not report a threshold that would define a meaningful IGF-1 change, so the statistical summaries alone cannot establish the practical importance of any possible difference.

The study summary also asks whether the extract changes IL-6, SARC-F score, muscle mass, muscle strength, and physical performance. No secondary results are posted. The IGF-1 result cannot be used to infer what happened to these other outcomes, and the record does not report evidence for or against effects on them.

The adverse-event record lists no serious adverse events and no deaths in either arm, alongside other adverse-event counts of 6 in placebo and 8 in extract. These are registry counts, not proof that an event is impossible or a complete account of safety. Details about event definitions and collection are not reported in the registry record.

Overall, the registry supports a cautious description of the observed IGF-1 summaries, their reported uncertainty, and the recorded adverse-event counts. It does not provide the analysis details needed to evaluate every statistical choice, and it does not settle the additional outcome questions raised in the study summary.

16. Why This Trial Matters Statistically

This trial illustrates why an estimated difference should be read together with its uncertainty. The extract and placebo arm means are close in the posted summaries, but the central issue is not simply whether the point estimate is negative. The confidence interval extends from -11.3 to 7.623 ng/dl, including zero and values on either side. That range makes clear that the observed estimate does not precisely determine the direction or magnitude of the difference.

It also illustrates the distinction between a study’s observed results and a planning exercise. The registry includes sample-size estimates based on the observed effect under stated assumptions. Those estimates can show how strongly planning requirements depend on the effect chosen: smaller target effects require more participants. They are not a substitute for the original design justification, which is not reported in the registry record, and they are not observed power.

The registry’s reporting scope is important for statistical interpretation. It describes several questions about muscle-related and blood measures, yet no secondary results are posted and no analyses are listed. This makes it necessary to separate the primary IGF-1 comparison from questions that remain unanswered in the posted results. The unadjusted p-value also cannot be interpreted as a multiplicity-adjusted finding when the record does not report a multiplicity plan.

Finally, the reported endpoint counts and adverse-event summaries are useful but incomplete without details about analysis populations, missing observations, and event collection. These are not technical footnotes: they affect how confidently readers can interpret the estimates and their coverage. The case is a practical example of reading numerical results alongside the information the registry does and does not document.

17. 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 provides a limited account of the statistical methods. It reports arm means, standard deviations, a mean difference, a confidence interval, and an unadjusted p-value, but does not identify the statistical test or interval method. The record does not state whether the comparison adjusted for baseline IGF-1 or other variables, or whether any assumptions were checked.

The outcome summaries list 38 participants for placebo and 40 for extract, while planned enrollment is 80. The record does not explain participant flow, the analysis population, or whether every randomized participant contributed an endpoint measurement. Missing-data procedures, exclusions, and sensitivity analyses are not reported in the registry record.

The registry summary raises questions about IL-6, SARC-F score, muscle mass, muscle strength, and physical performance, but no secondary results are posted. The record does not report a multiplicity approach, outcome-specific analysis methods, or a clinically meaningful threshold for the primary IGF-1 result. The original sample-size rationale and statistical analysis plan are also not reported.

Although the design is described as randomized and double-masked, details about the randomization process, allocation concealment, and who was masked are not reported. The record states that adverse events were recorded but does not report event definitions, collection procedures, or causal assessments. These limitations do not alter the posted numbers, but they constrain how fully the results can be evaluated and how far they can be interpreted.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: Effect Of Ophiochepalus Striatus Extract On Serum IGF-1 And IL-6 Levels In Elderly Patients With Sarcopenia — NCT05869383.
• Registry record last updated 2025-01-31; status last verified 2025-01.
• Results first posted 2025-01-31.
• 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.

21. Record Summary

NCT05869383 is a completed randomized, double-masked, parallel-group Phase 2 and Phase 3 trial sponsored by Universitas Sriwijaya. It planned enrollment of 80 elderly patients with sarcopenia and compared Ophiochepalus striatus extract, 2x5 grams a day for 14 days, with placebo at the same schedule.

The primary endpoint was serum IGF-1 at 2 weeks. The posted means were 78.92 ng/dl for placebo and 77.08 ng/dl for extract. The reported mean difference was -1.84 ng/dl, with a confidence interval from -11.3 to 7.623 ng/dl and an unadjusted p-value of 0.703. No secondary results are posted. The registry lists 0 serious adverse events and 0 deaths in each arm, with other adverse-event counts of 6 in placebo and 8 in extract.

Important details about analysis methods, missing data, analysis populations, multiplicity, and the original sample-size justification are not reported in the registry record.