GOLimumab and Methotrexate Versus Methotrexate in Very Early PsA: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for GOLimumab and Methotrexate Versus Methotrexate in Very Early PsA (NCT04108468), a randomized phase 3 study. The primary outcome is Psoriatic Arthritis Disease Activity Score (PASDAS) at 24 Weeks.

2. Clinical Question

3. Trial Design

This was an investigator-initiated, phase 3, randomized, double-blind, parallel-group trial sponsored by The Leeds Teaching Hospitals NHS Trust. It compared methotrexate alone with golimumab plus methotrexate in very early psoriatic arthritis. The registry record reports enrollment of 84 and a completed status. The recorded start date is 2015-10-27, and primary completion is listed as 2023-07.

Random allocation is intended to make the treatment groups comparable on average at the time of assignment, while blinding can reduce the influence of treatment knowledge on participants' reports, care, and outcome assessment. Those are general features of trial design; the registry record does not describe the allocation sequence, concealment procedures, who was masked, or how masking was maintained. Parallel-group means participants were assigned to one treatment group rather than crossing between the groups in the design described.

The primary outcome was PASDAS at 24 weeks, analyzed for the full analysis set. The registry lists additional PASDAS and other disease-activity outcomes at different follow-up times. A total of 69 outcome measures and 69 analyses are recorded, while the secondary outcome information describes 68 posted secondary measures. Detailed protocol information, including treatment schedules, the original sample-size justification, interim analyses, and prespecified statistical-analysis procedures, is not reported in the registry record. The trial's completed status is a record status; it does not itself indicate how complete each outcome dataset was or how participants were handled in each analysis.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Full analysis set

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 Psoriatic Arthritis Disease Activity Score (PASDAS) at 24 Weeks, measured over 24 weeks.

The primary endpoint was the Psoriatic Arthritis Disease Activity Score (PASDAS) at 24 weeks. It is a continuous score on a scale from 0-10, where higher values represent a worse outcome. A continuous endpoint retains differences across the score range rather than reducing participants to a binary category such as improved or not improved. Reporting group means therefore describes average disease-activity scores, while the mean difference expresses the contrast between those group averages.

Clinical trials use outcomes such as PASDAS to represent a defined aspect of a condition at a specified follow-up time. The choice of a 24-week measurement gives the primary comparison a common time point, but the registry record does not explain why this particular endpoint or time was selected, or provide a threshold for interpreting a change as clinically important. Those details are not reported in the registry record.

For the primary outcome, the recorded group sizes were 41 for methotrexate and 43 for golimumab plus methotrexate. Their posted means were 3.09 and 2.7, respectively, with standard deviations of 1.32 and 1.38. The standard deviation describes variation among participant scores within each group; it is not the uncertainty interval for the estimated group difference. The endpoint consequently supports a comparison of group averages and their statistical precision, but does not describe the full distribution of individual responses.

7. Results Posted in the Registry

• Golimumab & Methotrexate: mean 2.70 versus 3.09 on control; difference -0.39 (95% CI -0.97 to 0.19), standardized effect d = -0.29; z-test p = 0.186.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Psoriatic Arthritis Disease Activity Score (PASDAS) at 12 Weeks.

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Golimumab & Methotrexate: mean 3.01 versus 3.70 on control; difference -0.69 (95% CI -1.32 to -0.06), standardized effect d = -0.47; z-test p = 0.032.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Golimumab & Methotrexate than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Psoriatic Arthritis Disease Activity Score (PASDAS) at 36 Weeks.

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Golimumab & Methotrexate: mean 2.93 versus 3.30 on control; difference -0.37 (95% CI -1.52 to 0.78), standardized effect d = -0.14; z-test p = 0.527.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Golimumab & Methotrexate and the control. The interval gives the range of effects that remain compatible with the data.

Psoriatic Arthritis Disease Activity Score (PASDAS) at 52 Weeks.

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Golimumab & Methotrexate: mean 3.42 versus 3.36 on control; difference 0.06 (95% CI -0.57 to 0.69), standardized effect d = 0.04; z-test p = 0.852.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Golimumab & Methotrexate and the control. The interval gives the range of effects that remain compatible with the data.

The secondary outcomes include PASDAS at 12, 36, and 52 weeks, CPDAI at 12, 24, 36, and 52 weeks, and participant disease-activity visual analogue score at 24 weeks. The registry records 68 posted secondary outcome measures. These outcomes extend the assessment beyond the primary 24-week PASDAS endpoint, but they cover different instruments and follow-up times and should not be treated as repeated measurements of one single result.

Across the reported PASDAS analyses, the estimated differences do not follow one uniform pattern at every time point. The 12-week registry analysis has a 95% interval that does not include zero; the 36-week and 52-week registry analyses have intervals that do include zero. The primary 24-week analysis also has an interval that includes zero. This variation underscores why one secondary result should not be used alone to characterize the overall evidence or to override the primary endpoint.

Secondary outcomes can provide context about other aspects of disease activity and the course of scores over time. Their interpretation depends on the measurement, timing, analysis population, missingness, and prespecification. The registry record does not report a multiplicity adjustment or a hierarchy for these outcomes. When many outcomes and comparisons are examined, some apparently notable results can occur by chance even if there is no underlying difference. This general concern means unadjusted secondary p-values carry less weight than a clearly prespecified primary analysis and should be regarded as exploratory unless the analysis plan establishes otherwise.

Not all secondary result details are described in the record summary of outcomes. The broader count of posted measures also means that the named outcomes do not account for every secondary measure recorded. The complete analysis plan, selection rationale, and handling of multiple testing are not reported in the registry record. As a result, the secondary findings can indicate where estimates vary, but they do not support a single definitive summary of benefit or harm across all measured outcomes.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Psoriatic Arthritis Disease Activity Score (PASDAS) at 12 Weeks.
• Psoriatic Arthritis Disease Activity Score (PASDAS) at 36 Weeks.
• Psoriatic Arthritis Disease Activity Score (PASDAS) at 52 Weeks.
• Composite Psoriatic Disease Activity Index (CPDAI) at 12 Weeks.
• Composite Psoriatic Disease Activity Index (CPDAI) at 24 Weeks.
• Composite Psoriatic Disease Activity Index (CPDAI) at 36 Weeks.
• Composite Psoriatic Disease Activity Index (CPDAI) at 52 Weeks.
• Participant Disease Activity Visual Analogue Score at 24 Weeks.

9. Statistical Interpretation

10. Statistical Methods Explained

Statistical methods are useful when they connect the scientific question to an estimate and make its uncertainty visible. For this trial, the primary question concerns a difference in mean PASDAS at 24 weeks. The registry gives group means, standard deviations, and group sizes, and it also reports a linear-regression analysis of final values. These summaries and analyses answer related but not identical statistical questions.

What a mean difference represents

A mean is the arithmetic average of participant scores in a group. The unadjusted mean difference compares the average in one group with the average in the other, with the combination group contrasted against methotrexate in the posted recalculation. A negative estimate means the combination-group average is lower. Because higher PASDAS scores represent a worse outcome, that direction corresponds to a lower observed average score in the combination group. This is a statement about the direction of the group-level estimate, not a claim about the experience of each participant.

The simple recalculation uses the posted group summaries and does not account for other variables. It is therefore described as unadjusted. By contrast, the registry reports a linear regression analysis of final values. Regression estimates a contrast using a model, and may account for variables included in that model. The variables and full specification are not reported in the registry record. It is not possible to infer from the available description whether adjustment, missing-data handling, or other modeling choices explain the difference between the estimates.

Variation and uncertainty

The standard deviation describes how dispersed individual scores are around a group mean. The primary standard deviations are 1.32 for methotrexate and 1.38 for the combination group. Greater dispersion means individual observations are more spread out, but standard deviation is not itself a measure of uncertainty in the difference between the means. Uncertainty in an estimate is reflected by its confidence interval and is influenced by the amount of variation and the number of observations, among other features.

A confidence interval gives a range of values that are compatible with the data and the statistical procedure under its assumptions. It should be read alongside the point estimate: a narrow interval indicates more precision than a wide one, while an interval that includes zero for a difference does not exclude no difference at the confidence level used. The reported primary interval runs from -1.12 to 0.03 at 95% confidence. It includes zero, so the reported estimate does not rule out no mean difference at that interval level. An interval is not a guarantee that the true value lies inside it, nor does it provide a probability that a particular value is true.

Interpreting p-values

A p-value measures how incompatible the observed data are with a specified null model, assuming that model and the analysis assumptions hold. It is not the probability that the null hypothesis is true, and it does not measure the size or clinical importance of a difference. The registry's primary analysis reports p = 0.064. The simple unadjusted recalculation reports p = 0.186. These values belong to different analyses and should not be substituted for one another. Neither p-value alone describes the range of estimates compatible with the data; the confidence interval contributes that information.

Statistical significance is often assessed against a threshold chosen before analysis. The registry record does not state the trial's prespecified threshold or statistical plan, so interpretation should not assume that a particular threshold was designated by the investigators. Even when a threshold is known, crossing it is not a measure of the magnitude, reliability, or clinical relevance of a result. Estimates, intervals, study design, outcome definitions, and analysis choices all matter.

Why over-dispersion can matter

As a general statistical point, over-dispersion means that observed variability is greater than a model expects. When a model assumes less variation than is present, its standard errors can be too small and its confidence intervals too narrow, potentially making evidence appear more precise than it is. A model that accounts for the actual variability can produce more appropriate uncertainty estimates. This is a general explanation, not a claim that over-dispersion was detected or assessed in this trial. The registry record does not report an over-dispersion assessment.

Analysis populations and model details

The primary outcome population is called the full analysis set in the registry record. That label identifies the stated population for the primary endpoint, but the record does not give a definition of membership, the numbers with observed 24-week scores, or details of any imputation. The group counts in the posted primary summaries are 41 and 43. Those counts do not, without additional participant-flow or missingness information, establish whether every randomized participant contributed a score to every analysis.

The trial is recorded as randomized and double-blind, which are relevant design features, but a statistical interpretation also depends on implementation and analysis details. Random-sequence generation, allocation concealment, masking procedures, model covariates, handling of missing data, and protocol deviations are not reported in the registry record. The absence of those details limits independent evaluation of the analysis, but is not evidence that a particular procedure was or was not used.

11. Confidence Intervals and Precision

The primary estimate has meaningful uncertainty. The registry's linear-regression analysis reports a mean difference of -0.55 and a 95% confidence interval from -1.12 to 0.03. The interval includes zero and spans both a larger negative difference and a value slightly above zero. Thus, the posted estimate points toward a lower average PASDAS in the combination group, while the interval leaves uncertainty about the direction and size of the underlying difference.

The unadjusted recalculation gives a mean difference of -0.39, with a confidence interval that also includes zero. Its p-value is 0.186. The reported regression estimate and the recalculated estimate are based on different analyses, so their interval limits should not be combined or used as though they came from one model. The registry does not report enough model detail to explain the difference between them.

In general, a confidence interval represents the range of estimates compatible with the observed data under the method's assumptions. Wider intervals indicate less precision; narrower intervals indicate more precision. Whether an interval includes zero is relevant for a difference, but does not tell the reader whether all values inside the interval are clinically important. The record does not provide a threshold for clinical importance, so the clinical meaning of particular values within the interval cannot be determined from the posted information alone.

The reported standard deviations, 1.32 and 1.38, show variation in individual scores around the group means. The size of the group counts and the observed variation inform precision, but do not reveal all sources of uncertainty, including potential effects of missing outcomes or model choices. Participant-level data and fuller analysis details are not reported in the registry record. Precision should therefore be read from the confidence interval for each estimate, with attention to the method that produced it.

12. 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 illustrations are planning calculations based on the observed effect, rather than the trial's original design justification. The trial's own original sample-size assumptions and justification are not reported in the registry record. For the continuous-outcome calculations, the figures are participants per arm, not a combined total. The stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is set at the stated fraction of the observed effect.

The 80% power column describes the number of participants per arm that the calculation estimates would be needed to have an 80% chance of detecting the specified effect under those assumptions, if that effect and the assumptions applied. The 90% power column gives the analogous planning figure for a 90% chance. These are planning probabilities conditional on a hypothesized effect and model; they do not describe the probability that the trial's conclusion is correct. They are not observed power.

Rows that plan for 75% or 50% of the observed effect use smaller target effects than the full observed effect. Smaller effects are harder to distinguish from random variation, so the corresponding illustrations require more participants per arm. The figures are sensitive to the observed effect used as their starting point; they should not be mistaken for a recommendation or as evidence that the trial was designed to those values. The registry record does not report the original design assumptions, and the calculation assumptions should not be attributed to the investigators.

13. 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 = -0.390; pooled standard deviation σ = 1.351.
2. n = 2 × (1.96 + 0.842)² × 1.351² / -0.390² = 188.4, rounded up to 189 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 <- -0.39                      # observed difference in means
sigma <- 1.35106462086611                     # 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(4108468)
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 = 189 (80% power), 253 (90% power)
 75% of observed effect: n per arm = 335 (80% power), 449 (90% power)
 50% of observed effect: n per arm = 754 (80% power), 1,009 (90% power)
power.t.test: 189.4 
Simulated power at n = 189 per arm: 0.800 (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.

14. Analyses Reported by the Sponsor

The registry's own primary analysis is a linear regression of final values. It reports a mean difference of -0.55, a 95% confidence interval from -1.12 to 0.03, and p = 0.064. This is the analysis reported by the trial record. The posted summary means are 3.09 for methotrexate and 2.7 for golimumab plus methotrexate.

A separate recalculation from those summary statistics is unadjusted. It estimates the mean difference as -0.39 and reports p = 0.186; its confidence interval includes zero. This recalculation is not the same as the regression analysis. A regression estimate can differ from a raw comparison of group means, but the registry record does not provide the model details needed to identify why these estimates differ. The record marks no discrepancy between the posted and recalculated results.

Both analyses estimate a lower average final PASDAS in the combination group, and both leave uncertainty about whether the underlying difference is zero. The sponsor analysis should be read as the trial's reported model-based result, while the recalculation is a simple check using the summary statistics. Neither should be presented as though it replaced the other, and their p-values should remain tied to their respective analyses.

15. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when a study examines several outcomes, time points, treatment contrasts, or statistical tests. Even when each test uses a conventional significance threshold, the chance of at least one apparently notable result can increase as more tests are conducted. This is a general statistical issue, not evidence that any particular finding in this trial is false. It affects how much weight to place on isolated secondary results, especially when many measures are recorded.

The registry lists 69 outcome measures and 69 analyses, and 68 posted secondary outcome measures. It names several secondary disease-activity outcomes across multiple follow-up times. The record does not report whether the investigators used a multiplicity adjustment, a testing hierarchy, or another prespecified strategy for controlling interpretation across outcomes. It also does not report a complete statistical-analysis plan. Therefore, the posted secondary p-values should not be assumed to have a family-wise error adjustment, and the primary result should remain distinct from exploratory secondary comparisons.

Missing data are another important issue for continuous outcomes. If a participant does not have an observed score at a particular time, the analyzed group mean or model estimate may depend on how that missing value is handled. The record identifies the primary population as the full analysis set but does not define that set or report the number of observed scores at each time point, reasons for missingness, or imputation procedures. The listed group sizes are not a substitute for a participant flow description or a missing-data analysis.

Analysis-population labels also matter. Randomization describes the assignment process; an analysis population describes which participants and measurements enter a given estimate. The registry record does not report whether the primary analysis followed an intention-to-treat principle, how protocol deviations were handled, or whether sensitivity analyses assessed alternative missing-data assumptions. These omissions do not establish that such analyses were absent, only that they are not reported in the registry record. Without this information, readers cannot fully assess how robust the estimates are to missingness, population definitions, or multiple testing.

16. 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 counts are zero among 41 participants at risk in the methotrexate group and zero among 43 at risk in the golimumab-plus-methotrexate group. The record lists no serious adverse-event terms. Deaths are recorded as zero in both groups. These are counts for the posted safety record; they do not establish that no serious events could occur or that the groups have identical safety profiles.

Other adverse events are recorded for 38 of 41 participants in the methotrexate group and 41 of 43 in the combination group. The registry does not give further event definitions, severity breakdowns, event-specific terms, timing, or an account of how many events each participant experienced. These participant counts should not be treated as event counts or compared without considering how safety data were collected and classified.

Safety findings are descriptive in this record. Follow-up duration and the detailed safety-analysis methods are not reported in the registry record. The counts therefore describe what was posted, but they do not by themselves establish comparative risk or exclude uncommon events.

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

The primary results show lower average PASDAS in the golimumab-plus-methotrexate group than in the methotrexate group at 24 weeks. The score ranges from 0-10, and higher scores represent a worse outcome. The registry's regression estimate is -0.55, with a 95% confidence interval from -1.12 to 0.03. Because that interval includes zero, the posted analysis remains compatible with no mean difference as well as with differences in either direction within the interval.

This result does not establish that treatment works or does not work. A statistical estimate is not a recommendation for an individual, and a group average does not predict the score or response of every participant. The registry record does not give a clinically important difference threshold, so it does not establish whether a particular difference in PASDAS would be important to participants or clinicians.

The evidence is also limited to the measured outcome, its specified follow-up time, and the people represented in the analysis. It does not answer questions about other outcomes, longer-term results, or groups not represented by the trial description. Although several secondary outcomes are listed, their multiplicity and analysis details are not reported sufficiently to combine them into a single definitive conclusion.

The reported regression analysis and the unadjusted recalculation are related but distinct. Both point toward a lower average score in the combination group, while both leave uncertainty. The posted estimates should therefore be read with their intervals, the stated analysis method, and the limitations of the registry information, rather than as a binary verdict based only on a p-value.

18. Why This Trial Matters Statistically

This trial provides a useful setting for distinguishing an estimated difference from the certainty of that estimate. The primary group means point in one direction, but the confidence interval crosses zero. That combination illustrates why statistical interpretation should consider the point estimate, the uncertainty interval, and the analysis method together rather than reduce the result to a single p-value.

The record also makes clear that a direct comparison of summary means and a regression result can produce different estimates. These analyses address related questions, but the model-based estimate may depend on details not included in the record. Transparent reporting of model specifications, analysis populations, missing-data procedures, and the original design assumptions would help readers understand how results were generated and how robust they are.

Multiple outcome measures and follow-up times raise a separate interpretive challenge. Secondary results can add context, but without a reported multiplicity strategy it is difficult to assess how much evidential weight to give an isolated result among many comparisons. The distinction between primary and secondary questions is therefore statistically important, not merely a matter of presentation.

Finally, planning calculations based on an observed effect are illustrative rather than a record of the trial's original design process. Keeping those calculations separate from trial outcomes prevents planning scenarios from being misread as evidence about the study's achieved certainty. Overall, this record supports careful reading of estimates and uncertainty while making several relevant design and analysis details unavailable.

19. 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 posted primary result has a confidence interval that includes zero, so the estimate is not precise enough to rule out no mean difference under the reported analysis. The enrolled sample was 84, with group sizes of 41 and 43 in the primary summaries. This does not by itself explain the trial's precision; the original sample-size justification is not reported in the registry record.

Important implementation and analysis details are absent from the registry record. These include the eligibility criteria beyond the description of very early psoriatic arthritis, treatment doses and schedules, allocation concealment, masking procedures, the regression covariates, and the full statistical-analysis plan. The record also does not report the definition of the full analysis set, participant flow by time point, missing-data methods, or sensitivity analyses. These limitations prevent a complete independent assessment of how design and analysis choices may affect the estimates.

The record includes many outcome measures and analyses, but does not report a multiplicity strategy. This limits the confidence that can be placed in isolated secondary findings. Detailed secondary results are not all described in the record summary, and the relation between the posted outcomes and any prespecified hierarchy is not reported.

Safety information is also limited to posted counts. Event definitions, timing, severity details beyond the serious-event distinction, and exposure duration are not reported in the registry record. Finally, a clinical-importance threshold for PASDAS is not given. These gaps do not prove that the trial lacked the relevant procedures or assessments; they limit what can be concluded from the registry record alone.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: GOLimumab and Methotrexate Versus Methotrexate in Very Early PsA — NCT04108468.
• Registry record last updated 2025-12-02; status last verified 2025-11.
• Results first posted 2025-12-02.
• 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.

23. Record Summary

The GOLMePsA study was a completed, phase 3, randomized, double-blind, parallel-group trial sponsored by The Leeds Teaching Hospitals NHS Trust. It enrolled 84 participants with very early psoriatic arthritis and compared methotrexate with golimumab plus methotrexate. The primary endpoint was PASDAS at 24 weeks in the full analysis set.

The registry's linear-regression analysis reported a mean difference of -0.55, with a 95% confidence interval from -1.12 to 0.03 and p = 0.064. The interval includes zero. The simple unadjusted recalculation also has an interval including zero. The posted record lists additional disease-activity outcomes and safety counts, but does not report several details needed to assess multiplicity, missing data, model specification, or the original sample-size plan.