Narcotics vs NSAIDs for Post-operative Analgesia in Outpatient Rhinoplasty: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Narcotics vs NSAIDs for Post-operative Analgesia in Outpatient Rhinoplasty (NCT03457116), a randomized phase 4 study. The primary outcome is Average Pain Score.

2. Clinical Question

3. Trial Design

The registry describes a randomized, parallel-group Phase 4 study of postoperative pain management in outpatient rhinoplasty. Participants were assigned to receive either an NSAID regimen or an opiate regimen. The NSAIDS arm is described as 400mg of ibuprofen; the Opiates arm is described as Norco (hydrocodone 5mg- acetaminophen 325mg). The registry lists an enrollment of 70 and reports arm counts of 41 for NSAIDS and 29 for Opiates. These are the counts attached to the posted outcome results; the record does not explain the relationship between enrollment and the outcome counts.

Masking is listed as none. Thus, the registry does not describe the study as blinded. The record identifies NYU Langone Health as sponsor and marks the study completed. The listed start date is 2018-01-30, and the primary completion date is 2020-11-02. These record dates do not by themselves provide information about when an individual participant completed the pain survey.

The primary outcome was Average Pain Score on Day 0. A postoperative pain management survey asked participants to rate pain on a scale of 1 to 10, with higher scores indicating worse pain. The record also lists a secondary outcome concerning participants in the NSAIDs group who were upgraded to opiates because of high pain levels. The registry does not report the detailed allocation process, eligibility criteria, adherence procedures, or the exact timing of Day 0 assessment beyond that label. The trial’s original sample-size rationale and its prespecified statistical plan 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.

Overall Study

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 Average Pain Score, measured over Day 0.

The primary endpoint is Average Pain Score, recorded on Day 0. The registry describes it as a score from a postoperative pain management survey: participants indicate how much pain they experienced on their pain regimen using a scale from 1 to 10. A score of 1 is defined as no pain and a score of 10 as the worst pain possible; higher scores mean worse pain. The registry reports the endpoint as a mean with standard deviation.

A numeric pain rating is a continuous measure in the sense that average scores can be compared across treatment arms, even though each participant responds using a bounded scale. The mean summarizes the group’s reported level, while the standard deviation describes how dispersed individual scores are around that mean. These summaries address different features of the results: the mean describes the average score, and the standard deviation indicates variability among reported scores.

Pain scores are used to characterize the symptom being studied directly. In this trial, the endpoint is intended to compare reported pain under the assigned postoperative regimens. The record does not give further details about how survey completion was timed within Day 0, whether participants could submit more than one rating, or how incomplete survey responses were handled. It also does not report additional measurement properties or a threshold for interpreting a difference as important to participants.

7. Results Posted in the Registry

• Opiates: mean 3.14 versus 2.54 on control; difference 0.60 (95% CI -0.20 to 1.40), standardized effect d = 0.36; z-test p = 0.141.

8. Statistical Interpretation

9. Statistical Methods Explained

The registry reports each arm’s average pain score and standard deviation, then gives an unadjusted mean difference and an interval for that contrast. The following explains these statistics generally and how they relate to the posted comparison.

What does a mean difference represent?

For a continuous outcome, the mean is the arithmetic average of participants’ recorded scores in an arm. A mean difference compares the arm averages. Here, the contrast is described as Opiates minus NSAIDS: 3.14 minus 2.54 is reported as a mean difference of 0.6. The sign depends on the order of subtraction. Since the scale is higher for worse pain, a positive value in this direction means the observed average is higher in the Opiates arm. A difference in means summarizes the group-level contrast; it does not imply that each participant’s score differed by that amount.

What does the standard deviation describe?

The standard deviation describes how dispersed participant scores are around an arm’s mean. The posted values are 1.57 for NSAIDS and 1.75 for Opiates. Larger spread means scores vary more around the group average. Standard deviation is not the same as the standard error or the confidence interval: it describes variation among individual observations, whereas standard error and confidence intervals concern uncertainty in an estimated quantity such as a mean or mean difference.

In general, dispersion matters because an average from highly variable observations is less precisely estimated than an average from less variable observations when other features are comparable. The arm counts also contribute to precision. The registry gives counts of 41 for NSAIDS and 29 for Opiates. The posted interval for the contrast reflects uncertainty in the estimated mean difference; the arm standard deviations alone do not communicate that uncertainty.

How should the p value be understood?

The unadjusted p value is 0.141. In general, a p value describes how unusual data at least as incompatible with a specified null model would be if that model and the test assumptions held. 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 record calls the value unadjusted and does not state a trial-specific threshold for judging statistical evidence. It also does not report the details of the test used or a prespecified analysis plan.

Why consider the interval as well?

A confidence interval gives a range of estimates compatible with the observed data under the method’s assumptions. Its width conveys precision: a wider interval leaves more uncertainty about the magnitude and possibly the direction of the contrast. The interval reported for this result includes values below and above zero. This indicates that the data do not restrict the plausible contrast to a single direction. The interval is more informative about uncertainty than the point estimate by itself, but its exact interpretation depends on the interval method and coverage level, which are not detailed in the registry record.

What does randomization contribute?

In general, random assignment is intended to make treatment groups comparable on average with respect to factors that could affect the outcome, including factors that were not measured. It does not guarantee identical groups in a particular trial. The registry identifies the design as randomized and parallel, but does not report the sequence-generation method, allocation concealment, or any adjustment for baseline characteristics. Masking is listed as none. Knowledge of the assigned regimen could affect reported pain or other aspects of study conduct; the record does not quantify whether or how that occurred.

The trial is identified as continuous-outcome research, and the primary summary is a mean with standard deviation. The record does not report a transformation, a model-based adjustment, or a method for handling unusual observations. General concerns about whether a mean adequately represents a bounded rating scale depend on the data distribution and analysis plan, neither of which is described in detail. The posted group summaries provide a useful description, but they do not show the individual score distribution.

The registry lists five outcome measures and no analyses. That distinction matters: posted summary results are present, but an analysis plan with model specifications, covariates, missing-data rules, and multiplicity procedures is not reported. In general, statistical interpretation is strongest when the outcome, contrast, analysis method, and handling of incomplete observations are prespecified and transparent. Those details cannot be reconstructed from the summary statistics alone.

10. Confidence Intervals and Precision

The mean difference is reported as 0.6 points, with Opiates minus NSAIDS as the comparison direction. Its confidence interval extends from a value below zero to a value above zero. Since zero represents no difference between the arm means, the interval includes both the possibility of a negative contrast and a positive contrast. The registry record’s interval therefore does not confine the estimated difference to one direction.

In general, a confidence interval represents uncertainty in an estimate under the assumptions of the method used to calculate it. It is not a range that contains every participant’s pain score, nor does it describe the distribution of individual scores. A narrower interval indicates greater precision about the contrast, while a wider interval indicates less precision. The registry record does not identify the interval’s coverage level or calculation method, so those features should not be assumed.

The arm means are 2.54 for NSAIDS and 3.14 for Opiates; their reported standard deviations are 1.57 and 1.75. The standard deviations describe score variation within each arm, while the interval addresses uncertainty in the between-arm mean difference. The posted arm counts are 41 and 29. These counts, along with the score variability, are relevant to the precision of the estimated contrast.

The point estimate is not the full result: an estimated difference of 0.6 coexists with an interval that spans zero and an unadjusted p value of 0.141. This means the observed contrast is estimated with uncertainty, and the registry result does not establish a precise direction or magnitude for the underlying difference. The record does not report a clinically important difference threshold, so statistical uncertainty cannot be translated into a judgment about practical importance.

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 figures are planning illustrations based on the observed mean difference, not counts from the trial. The listed values are participants per arm, not total events. The calculations assume a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. They use the stated fraction of the observed effect as the effect to detect. The trial’s original design assumptions and sample-size justification are not reported in the registry record.

For planning at 100% of the observed effect, the illustration lists 119 participants per arm for 80% power and 159 participants per arm for 90% power. For planning at 75% of the observed effect, it lists 211 participants per arm for 80% power and 282 participants per arm for 90% power. For planning at 50% of the observed effect, it lists 473 participants per arm for 80% power and 634 participants per arm for 90% power.

In general, power is the probability that a planned statistical test will detect an effect of the specified size under the assumptions used for planning. The 80% and 90% columns represent different target probabilities under those assumptions; the higher target generally requires a larger planned sample. The rows also illustrate that smaller effects need more participants to detect, all else equal. The associated curve should be read as a visual presentation of this same relationship, not as a result observed during the trial.

These are planning calculations, not observed power. They use the observed effect as an input, so they should not be interpreted as evidence about the probability that the completed trial detected a true effect. They also do not establish the sample size that the investigators originally intended to recruit; that rationale is not reported in the registry record.

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 = 0.600; pooled standard deviation σ = 1.647.
2. n = 2 × (1.96 + 0.842)² × 1.647² / 0.600² = 118.2, rounded up to 119 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 <- 0.6                      # observed difference in means
sigma <- 1.64650253210716                     # 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(3457116)
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 = 119 (80% power), 159 (90% power)
 75% of observed effect: n per arm = 211 (80% power), 282 (90% power)
 50% of observed effect: n per arm = 473 (80% power), 634 (90% power)
power.t.test: 119.2 
Simulated power at n = 119 per arm: 0.806 (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 record lists five outcome measures, identifies Average Pain Score as the primary outcome, and lists one secondary outcome concerning NSAIDs-group participants upgraded to opiates because of high pain levels. It reports no analyses in the registry analysis listing. Results for that secondary outcome and the other outcome measures are not reported in the registry record. The study summary also says potential contributing factors would be evaluated, but results of such evaluations are not reported.

Multiplicity is a general concern when a study examines several outcomes, time points, subgroups, or analytic approaches. Repeated testing can increase the chance of finding an apparently notable result by chance, depending on how the analyses are conducted. A prespecified hierarchy or an adjustment can help clarify how multiple results should be interpreted. The registry record does not report whether multiplicity was addressed, which outcomes were included in any planned multiplicity strategy, or whether the posted primary result was selected from a broader set of analyses.

The registry record does not report how missing pain scores were handled, whether all randomized participants contributed to the endpoint analysis, or which analysis population was used. The reported arm counts are 41 for NSAIDS and 29 for Opiates, but those counts alone do not establish the number of participants with complete endpoint data or the analysis rules. It is also not reported whether any participants changed regimens or withdrew, apart from the secondary outcome’s description of possible upgrades from NSAIDs to opiates.

In general, missing-data methods matter because an analysis based only on available scores can be affected if missingness is related to pain, treatment, or other participant characteristics. Analysis-population definitions matter because an intention-to-treat analysis, a per-protocol analysis, and a safety population can include different records and answer different questions. These are general methodological considerations; the registry does not identify which approach was used for the posted means or comparison. Consequently, the summary statistics should be interpreted without assuming a particular missing-data or population strategy.

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.

The registry reports serious adverse event counts, other adverse event counts, and deaths for the NSAIDS and Opiates arms. In the NSAIDS arm, the record gives 0 serious adverse events among 41 at risk, 0 other adverse events among 41 at risk, and 0 deaths. In the Opiates arm, it gives 0 serious adverse events among 29 at risk, 0 other adverse events among 29 at risk, and 0 deaths.

These are the event counts recorded in the registry, not evidence that no other symptoms or experiences occurred. The record does not provide event descriptions, severity breakdowns beyond the serious-versus-other categories, or additional detail about how events were collected. A count of zero means no events in that category were reported for the corresponding group in this record; it does not establish that an event is impossible or that the regimens have identical safety profiles.

In general, safety counts are interpreted alongside the number of participants monitored, the duration and completeness of follow-up, and the definitions and collection procedures used. Further details about follow-up duration and safety ascertainment are not reported in the registry record. The counts therefore describe only the adverse-event information posted, and should not be treated as a comprehensive safety comparison.

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

The posted primary result describes average pain scores on Day 0 under the assigned postoperative regimens. The NSAIDS mean is 2.54 and the Opiates mean is 3.14, with a reported mean difference of 0.6 for Opiates minus NSAIDS. Because larger scores indicate worse pain, the observed contrast points to a higher average score in the Opiates arm. The interval includes values below and above zero, and the unadjusted p value is 0.141, so the estimate remains uncertain in direction and magnitude.

This result does not establish that one regimen is better or worse for an individual participant. Arm averages do not describe every participant’s experience, and the study’s primary outcome is a pain rating rather than a measure of every aspect of recovery. The registry does not report a threshold for a clinically important difference, so the size of the observed contrast cannot be categorized as meaningful or unimportant on the basis of the posted record alone.

The result also does not answer every question raised by the study summary. The record mentions potential contributing factors and lists a secondary outcome about participants in the NSAIDs group upgraded to opiates, but it does not report results for these questions. The available primary endpoint summary cannot establish whether pain scores varied by participant characteristics, whether regimens were followed as intended, or how results might differ at times other than Day 0.

Finally, the posted adverse-event counts are zero in the serious and other adverse event categories for both arms, with zero deaths reported. These registry counts should not be interpreted as proof that no adverse effects occurred or as a complete safety comparison, particularly because event-collection and follow-up details are not reported. The soundest reading is limited to the posted pain-score comparison and the recorded adverse-event counts, with the uncertainty and reporting gaps kept in view.

16. Why This Trial Matters Statistically

This trial illustrates why an estimated difference, its uncertainty, and the outcome’s meaning need to be considered together. The point estimate is a 0.6-point higher average pain score in the Opiates arm relative to NSAIDS, but the interval spans zero. Looking only at the means could suggest a clear separation; considering the interval shows that the estimate does not precisely establish the direction of the underlying contrast.

It also illustrates the distinction between variability in individual scores and uncertainty about a group comparison. The standard deviations describe spread within each arm, while the confidence interval describes uncertainty in the mean difference. Reporting both helps readers distinguish the diversity of participant responses from the precision of an estimated average effect.

Randomization is an important design feature, but it does not replace transparent reporting of analysis choices. The record identifies randomization and no masking, yet does not report the allocation method, missing-data rules, analysis population, or multiplicity approach. Such details help readers assess how the posted estimate was generated and how much reliance to place on it.

The planning illustration offers a further statistical lesson: sample-size requirements depend on the effect a future study aims to detect. The listed scenarios show larger participant requirements when planning around smaller fractions of the observed effect. These calculations are distinct from the trial’s original design rationale, which is not reported, and do not turn the observed result into a power statement.

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.

Several trial-specific limitations of interpretation follow from what the registry reports and does not report. The design is listed as unmasked. Pain was recorded by participant survey, and the registry does not describe procedures to reduce the influence of participants’ knowledge of their assigned regimen on their reports. This does not show that reporting was biased, but it means the possibility cannot be assessed from the record.

The primary endpoint is limited to Average Pain Score on Day 0. The record does not define the precise survey timing within that day or report pain scores at other time points. It therefore does not establish how the arm comparison changed over time or describe the broader course of postoperative pain. The score is a 1-to-10 rating, but a threshold for a clinically important difference is not reported.

The posted arm counts are 41 for NSAIDS and 29 for Opiates, with means and standard deviations reported for each. The registry does not explain the flow from enrollment to the endpoint counts, provide participant-level distributions, or describe whether all randomized participants were included in the analysis. Eligibility criteria, adherence, withdrawals, and missing-score handling are not reported in the registry record.

The record also does not report the trial’s original sample-size assumptions, the detailed statistical plan, multiplicity handling, or analyses of potential contributing factors. The secondary outcome about NSAIDs-group participants upgraded to opiates is listed, but its result is not reported. These gaps limit assessment of the completeness and prespecification of the reported comparison. They do not alter the posted summary values, but they constrain conclusions that can be drawn from them.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: Narcotics vs NSAIDs for Post-operative Analgesia in Outpatient Rhinoplasty — NCT03457116.
• Registry record last updated 2021-11-23; status last verified 2021-10.
• Results first posted 2021-11-23.
• 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.

21. Record Summary

NCT03457116 is a completed, randomized, parallel-group Phase 4 study sponsored by NYU Langone Health. It compared 400mg of ibuprofen in the NSAIDS arm with Norco (hydrocodone 5mg- acetaminophen 325mg) in the Opiates arm for postoperative pain after outpatient rhinoplasty. Masking is listed as none. The record lists an enrollment of 70 and reports primary endpoint arm counts of 41 for NSAIDS and 29 for Opiates.

The primary outcome was Average Pain Score on Day 0, rated on a scale from 1 to 10, with higher scores indicating worse pain. The reported means were 2.54 for NSAIDS and 3.14 for Opiates. The mean difference for Opiates minus NSAIDS was 0.6; its confidence interval spans zero, and the unadjusted p value is 0.141. The registry lists five outcome measures and no analyses. It reports zero serious adverse events, zero other adverse events, and zero deaths in each arm.