Regional Versus General Anesthesia for Promoting Independence After Hip Fracture: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Regional Versus General Anesthesia for Promoting Independence After Hip Fracture (NCT02507505), a randomized na study. The primary outcome is Death or Inability to Walk 10 Feet or Across a Room Without Human Assistance.

2. Clinical Question

The primary endpoint combines death with a measure of walking ability. It therefore captures whether a participant experienced either of these outcomes by the specified follow-up. It is a count of participants meeting the endpoint, rather than a measure of walking distance or the severity of disability among those unable to walk independently.

The registry record describes the trial’s purpose as determining whether the two types of standard-care anesthesia are the same or whether one is better for people with hip fractures. The posted primary result is a comparison of the observed endpoint counts and estimated risks. The record does not report an equivalence margin or a noninferiority margin, so the comparison should not be interpreted as a formal demonstration that the approaches are equivalent.

3. Trial Design

The registry record describes a completed, randomized, double-masked, parallel-group trial sponsored by the University of Pennsylvania. It lists regional anesthesia and general anesthesia as the two procedures under comparison. The recorded enrollment is 1848. The study began in 2016-02, and primary completion was recorded in 2021-06.

For the primary endpoint, the registry reports 132 participants with the event among 712 in the regional anesthesia arm and 132 among 733 in the general anesthesia arm. These are the denominators and counts posted for that outcome; the registry record does not explain how they relate to the overall enrollment. Other outcomes have different posted denominators, and their participant counts should be read separately rather than treated as a single analysis population.

The primary outcome was assessed by telephone interview approximately 60 days after randomization. The record also lists secondary outcomes concerning overall health and disability, return to home, chronic pain, cognitive function, all-cause mortality, assistive devices for walking, acute postoperative pain, and satisfaction with care. Additional outcome measures are posted, but the registry record does not describe a complete analysis plan for them.

Randomization supports a comparison of assigned groups, but the registry record does not report details such as the randomization procedure, the masking procedures, the eligibility criteria, or the planned handling of participants who did not complete follow-up. The original sample-size justification and the trial’s prespecified statistical analysis 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.

Before assignment: Of the 1848 participants who provided informed consent, 248 withdrew consent prior to randomization; 1600 participants were randomly assigned to a treatment group and continued in the study.

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 Death or Inability to Walk 10 Feet or Across a Room Without Human Assistance, measured over Approximately 60 days after Randomization.

The primary endpoint is the number of participants who died or were unable to walk 10 feet or across a room without human assistance, assessed approximately 60 days after randomization. It combines a fatal outcome with a functional outcome: a participant meets the endpoint if either condition applies. The registry describes assessment by telephone interview.

This kind of combined endpoint can represent more than one important dimension of a clinical course. In this case, it includes survival and the ability to walk without another person’s help. A combined measure can capture a broader outcome than either component alone, but it also means the overall result does not tell the reader which component contributed to the event count. The registry record does not post separate primary results for death and inability to walk without assistance.

The posted counts are 132 participants with the endpoint among 712 in the regional anesthesia arm and 132 among 733 in the general anesthesia arm. The endpoint is expressed as a count of participants, with the arm-specific denominators needed to interpret those counts. It does not describe the degree of walking difficulty among participants who could not walk independently, nor does the registry record report the endpoint’s component-specific results. The interpretation should therefore stay focused on the combined outcome as defined.

7. Results Posted in the Registry

• General Anesthesia: 18.0% (132/733) versus 18.5% (132/712) on control; risk difference -0.5 percentage points (95% CI -4.5 to 3.5), risk ratio 0.97 (0.78–1.21); unadjusted two-proportion z-test p = 0.794.

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.

Satisfaction With Care

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • General Anesthesia: 14.7% (97/661) versus 13.1% (85/647) on control; risk difference 1.5 percentage points (95% CI -2.2 to 5.3), risk ratio 1.12 (0.85–1.46); unadjusted two-proportion z-test p = 0.422.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between General Anesthesia and the control. The interval gives the range of effects that remain compatible with the data.

Postoperative Delirium

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • General Anesthesia: 19.7% (124/629) versus 20.5% (130/633) on control; risk difference -0.8 percentage points (95% CI -5.2 to 3.6), risk ratio 0.96 (0.77–1.20); unadjusted two-proportion z-test p = 0.715.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between General Anesthesia and the control. The interval gives the range of effects that remain compatible with the data.

Inpatient Mortality

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • General Anesthesia: 1.6% (13/790) versus 0.6% (5/782) on control; risk difference 1.0 percentage points (95% CI -0.0 to 2.1), risk ratio 2.57 (0.92–7.18); unadjusted two-proportion z-test p = 0.061.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between General Anesthesia and the control. The interval gives the range of effects that remain compatible with the data.

The secondary outcomes cover several domains, including satisfaction with care, postoperative delirium, and inpatient mortality, as well as broader areas such as health and disability, return to home, chronic pain, cognition, all-cause mortality, walking assistance, and acute postoperative pain. The posted measures therefore address outcomes that are related to, but not identical with, the primary combined endpoint. Some are functional or patient-reported, while others concern events during the hospital stay or early postoperative period.

The posted comparisons do not present a consistent pattern of clear separation between the anesthesia arms. Their estimates and intervals should be interpreted outcome by outcome, with attention to the differing definitions and follow-up periods. The primary result concerns the combined endpoint approximately 60 days after randomization; a secondary result at another time or on another construct does not replace that primary comparison. Nor can a single secondary measure explain which component drove the primary endpoint.

Unadjusted secondary results carry less weight when many outcomes are examined. Even when no real treatment differences exist, looking across many comparisons makes it more likely that some estimates will appear notable by chance. The registry record does not report a multiplicity adjustment or a prespecified hierarchy for interpreting secondary outcomes. It also lists no reported analyses for the posted secondary outcomes. These results are best treated as exploratory signals rather than as independent confirmation of a treatment effect.

Comparisons across outcomes also require caution because their denominators, assessment schedules, and event definitions differ. The record does not report why the analysis counts vary or how missing measurements were handled. Taken together, the secondary results offer context about several aspects of care, but they do not overturn or sharpen the primary finding without a fuller, prespecified analysis plan and appropriate consideration of multiple testing.

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

• Overall Health and Disability
• Ability to Return to Home
• Chronic Pain
• Cognitive Function
• All-cause Mortality
• Need for Assistive Devices for Walking
• Acute Postoperative Pain
• Satisfaction With Care

9. Statistical Interpretation

10. Statistical Methods Explained

The primary endpoint is binary at the participant level: a participant either meets the combined definition of death or inability to walk without human assistance, or does not. The posted arm results give the number with the event and the number assessed for that outcome. The estimated risks express those counts relative to their respective arm denominators. These quantities describe the observed data; they do not, by themselves, explain why an event occurred or establish that assignment caused an individual outcome.

What does the risk difference represent?

The risk difference compares the event risks between the two arms. In the posted comparison, the direction is general anesthesia minus regional anesthesia. A value below zero means the estimated risk is lower in the general anesthesia arm; a value above zero would mean it is higher. A value of zero represents no difference in estimated risk. The estimate is -0.005, with a confidence interval from -0.045 to 0.035.

The difference is expressed on the risk scale, making it a direct comparison of the estimated proportions with the endpoint. It is not a ratio. Other measures, such as risk ratios and odds ratios, describe the comparison on different scales. Those measures can be useful in other settings, but their numerical values do not have the same interpretation as a risk difference. The registry’s posted primary comparison includes a risk ratio of 0.971 with interval 0.781 to 1.208, and an odds ratio of 0.965 with interval 0.739 to 1.26.

How should a confidence interval be read?

A confidence interval describes the uncertainty around an estimated effect under the assumptions of the statistical method. It indicates which effect values are reasonably compatible with the observed data and the method. It does not give a probability that a particular effect is true, and it does not account automatically for every possible source of bias, missing data, or model error.

For the primary comparison, the interval includes zero and extends to values on either side. This means the posted data do not precisely distinguish a lower risk in one arm from a lower risk in the other. The interval’s width is relevant: a nonsignificant result with a wide interval can leave substantial uncertainty about the direction and size of the effect. The registry record does not report a prespecified clinically important difference, so the interval cannot be judged against such a threshold.

What does the p-value add?

The unadjusted p-value is 0.794. In general, a p-value measures how unusual data at least as discrepant as those observed would be under a specified null hypothesis and statistical model. It is not the probability that the null hypothesis is true, a measure of clinical importance, or evidence that the groups are exactly alike. It should be interpreted alongside the estimated effect and its interval.

The record lists no reported analyses for the posted secondary outcomes. The primary comparison is presented with an unadjusted p-value; the registry record does not describe adjustments for covariates, clustering, multiple testing, or other features of a statistical model. It also does not report the exact method used to calculate the posted confidence interval and p-value. Those details should not be inferred from the values alone.

Why does the endpoint definition matter?

Combining death with inability to walk without human assistance makes the primary outcome a measure of whether either event occurred by follow-up. The analysis treats the combined endpoint as one binary outcome. That provides a single comparison, but it cannot identify the separate association with death or with walking ability. The record does not post a breakdown of the primary result by component.

Outcome timing and assessment also shape the interpretation. The primary endpoint is assessed approximately 60 days after randomization by telephone interview. It is a follow-up status measure, not a time-to-event analysis. The registry record does not report how missing interviews or uncertain reports were handled, whether outcome assessors remained masked, or whether the endpoint definition changed during the trial.

What can be inferred from the trial design?

Random allocation is intended to support a fair comparison by balancing factors across assigned groups on average. A parallel-group design means the arms are compared as separate groups. The registry identifies the study as double-masked, but does not report who was masked or how masking was maintained. These design labels alone do not establish that all potential sources of bias were prevented.

The registry reports enrollment of 1848, but the primary outcome denominators are 712 and 733. Since the record does not explain the relationship between enrollment and the endpoint denominators, the reason for the difference is not known. The original statistical plan, analysis-population definitions, and missing-data procedures are not reported in the registry record. These omissions limit assessment of whether the posted analysis followed a prespecified approach.

11. Confidence Intervals and Precision

The primary risk-difference estimate is -0.005, with a 95% confidence interval from -0.045 to 0.035. The interval includes zero, so the posted data are compatible with no difference as well as with differences in either direction. The estimate alone is not a precise statement of the effect: the range of values in the interval is important to its interpretation.

Precision concerns how narrowly an effect is estimated. A narrower interval would indicate less statistical uncertainty under the method used; a wider interval indicates more. The posted primary interval leaves uncertainty about both the direction and size of the difference. The unadjusted p-value of 0.794 is consistent with the interval crossing zero, but it does not replace the interval or establish equivalence.

The confidence interval does not account automatically for unreported design or analysis issues. The registry record does not report the original analysis plan, the handling of missing outcomes, or a clinically important threshold for the primary result. Without a threshold, it is not possible to determine from the interval alone whether every compatible effect would be considered unimportant. The reported interval describes statistical uncertainty, not the full uncertainty surrounding the conduct and interpretation of the trial.

There are also limits to what this interval captures about the endpoint. It applies to the combined outcome of death or inability to walk without human assistance at approximately 60 days. Separate component-specific estimates are not reported in the registry record. The interval should not be taken as a confidence interval for either component considered on its own or for outcomes at other follow-up times.

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 planning figures are participants per arm, not total participants and not total events. They are illustrations based on the observed effect, rather than the trial’s original design calculations. The listed assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect used for each illustration is a stated fraction of the observed effect.

The 80% power column gives the estimated participants per arm for a future study to have an 80% chance of detecting the specified effect under the planning assumptions, if that effect and the assumptions hold. The 90% power column uses a higher target chance of detecting that effect and therefore lists a larger planning requirement. These figures are not observed power for the completed trial.

The planning rows consider 100% of the observed effect, 75% of the observed effect, and 50% of the observed effect. The smaller the effect a study aims to detect, the more participants are generally needed to distinguish it from random variation under a fixed design and statistical threshold. The listed values illustrate that relationship for the primary comparison; they are not a recommendation or a statement of the trial’s original target.

The original sample-size assumptions and justification are not reported in the registry record. The planning figures use the posted observed effect and the stated illustration assumptions, so they should be read as hypothetical design calculations rather than evidence about whether the completed trial was adequately planned or powered.

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, p₀ and p₁ are the control and treatment proportions, and p̄ is their average.

Worked calculation for this trial

1. Control proportion p₀ = 0.185; treatment proportion p₁ = 0.180; average p̄ = 0.183.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.5465 = 1.0712.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.5465 = 0.4600.
4. n = (1.0712 + 0.4600)² / (-0.0053)² = 83,100.3, rounded up to 83,101 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
p0 <- 0.185393258426966                          # control proportion
p1 <- 0.180081855388813                          # treatment proportion
n_per_arm <- function(power, frac = 1) {
  q1 <- p0 + (p1 - p0) * frac               # smaller effect = fraction of the observed difference
  pbar <- (p0 + q1) / 2
  z_b <- qnorm(power)
  ceiling(round((z_a * sqrt(2 * pbar * (1 - pbar)) + z_b * sqrt(p0 * (1 - p0) + q1 * (1 - q1)))^2 / (q1 - p0)^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 (unrounded n per arm)
cat("power.prop.test:", round(power.prop.test(p1 = p0, p2 = p1, power = 0.80)$n, 1), "\n")

# Simulation: how often does the z-test reject at the 80%-power sample size?
set.seed(2507505)
n    <- n_per_arm(0.80)
reps <- 20000
x0 <- rbinom(reps, n, p0); x1 <- rbinom(reps, n, p1)
ph <- (x0 + x1) / (2 * n)
z  <- ((x1 - x0) / n) / sqrt(ph * (1 - ph) * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(z) > z_a, na.rm = TRUE), reps))

Output from running the code

100% of observed effect: n per arm = 83,101 (80% power), 111,248 (90% power)
 75% of observed effect: n per arm = 148,152 (80% power), 198,332 (90% power)
 50% of observed effect: n per arm = 334,276 (80% power), 447,501 (90% power)
power.prop.test: 83100.3 
Simulated power at n = 83,101 per arm: 0.795 (20000 replicates)

The simulation draws many pairs of event counts at the planned sample size and counts how often the two-proportion z-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. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when statistical tests are conducted for multiple outcomes or comparisons. If each test is considered separately without adjustment, the chance of at least one apparently unusual result can increase as more tests are examined. This matters when interpreting a set of secondary outcomes: an isolated result may be compatible with chance, particularly if it was not designated in advance as a key test.

The registry lists multiple secondary outcomes and reports 11 secondary measures. It does not report a multiplicity adjustment, a hierarchy of outcomes, or a plan identifying which secondary comparisons were confirmatory. The registry also lists no reported analyses for the secondary measures. Consequently, the posted secondary comparisons should not be treated as if each had been protected from the risks of multiple testing by a stated analysis strategy.

The record does not report an analysis-population definition for the primary or secondary outcomes, such as whether analyses followed randomized assignment regardless of treatment received. It also does not report how missing outcomes, incomplete follow-up, withdrawals, or deviations from assigned procedures were handled. The differences among the posted outcome denominators make those omissions particularly relevant to interpretation, but they do not establish why denominators differ or whether data are missing.

The registry record does not report the original statistical analysis plan, covariate adjustment strategy, interim analyses, or stopping rules. None of these details should be inferred from the posted results. Without them, readers cannot fully assess whether the reported analyses were prespecified, how potential missingness was addressed, or how the primary and secondary findings were intended to be prioritized. These gaps do not invalidate the posted counts, but they limit how confidently the results can be interpreted as confirmatory evidence.

15. 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 serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: death nos (8.3%), anemia (6.5%), transfusion (3.6%), fall (3.1%), urinary tract infection (2.5%).

The adverse-event record lists serious events affecting 255 participants at risk in the regional anesthesia group and 242 in the general anesthesia group. For other events, it lists 278 participants at risk in the regional group and 286 in the general group. The record also lists deaths of 98 and 92, respectively. These are separate posted figures; the registry record does not explain their relationship to each other or to the primary endpoint counts.

The serious terms most frequently listed include Death NOS (8.3%), anemia (6.5%), transfusion (3.6%), fall (3.1%), urinary tract infection (2.5%), and acute kidney injury (2.2%). The record does not specify the denominator or arm-specific distribution for these term percentages, nor does it provide a timeframe for the overall adverse-event figures. The terms and counts should therefore be read as registry safety reporting, not as proof that anesthesia caused an event or that one arm had a particular causal safety profile.

Safety interpretation would also require consistent definitions, timing, ascertainment, and analysis of events by randomized group. Those details are not reported in the registry record. The listed figures describe what was posted and do not by themselves establish comparative risk.

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

The primary result describes the observed comparison between randomized arms for a combined endpoint approximately 60 days after randomization. The estimated event risks were 0.185 for regional anesthesia and 0.180 for general anesthesia. The estimated risk difference was -0.005, with a confidence interval from -0.045 to 0.035 and an unadjusted p-value of 0.794. The interval includes zero and values on either side, so the result does not precisely establish which arm had the lower risk.

This finding does not demonstrate that the anesthesia approaches are equivalent. Equivalence requires a prespecified margin defining how much difference can be accepted, together with an analysis designed to assess that question. The registry record does not report such a margin. A nonsignificant test is not evidence that the effects are identical, and it does not establish that any possible difference is too small to matter.

The result also does not establish a clear difference. The estimate is close to zero on the risk-difference scale, but its confidence interval remains compatible with both directions of effect. The statistical uncertainty should be considered alongside clinical context, which cannot be resolved from the registry summary alone. In particular, the record does not state a clinically important threshold for this endpoint.

The endpoint combines death and inability to walk 10 feet or across a room without human assistance. The registry does not report the primary result separately for those components. The finding therefore cannot tell whether the groups differed for death, walking ability, or both. It applies to the specified follow-up and endpoint definition, not automatically to other outcomes, longer-term recovery, or other populations.

The posted results also do not establish that all potential sources of bias or missing-data effects were addressed. The registry record does not report the analysis populations, missing-outcome procedures, or complete statistical plan. A careful reading is therefore limited to the comparison and uncertainty described by the posted endpoint data, without extending the conclusion to claims the record cannot support.

17. Why This Trial Matters Statistically

This trial poses a clinically direct comparison between two anesthesia procedures used as standard care for people with hip fractures. Its primary endpoint brings together survival and an aspect of walking independence, making the statistical question about a patient-relevant outcome rather than only a laboratory or procedural measure.

The primary result illustrates why an estimate, an interval, and a test answer different questions. The estimated risk difference is -0.005, while its confidence interval ranges from -0.045 to 0.035. The p-value is 0.794. The test does not provide strong evidence against a null difference, but the interval shows that uncertainty remains about both the direction and size of the effect. Reporting only the p-value would conceal that uncertainty.

The trial also highlights the distinction between failing to detect a difference and demonstrating equivalence. The registry’s stated purpose refers to whether the anesthesia approaches are the same or one is better, but the record does not report an equivalence margin or a formal equivalence analysis. Statistical interpretation must follow the analysis and quantities actually reported rather than treating a nonsignificant comparison as proof of sameness.

Finally, the registry record makes clear why outcome definitions, denominators, and analysis plans matter. The primary endpoint is composite, the posted denominators vary across outcomes, and the record does not describe missing-data handling or the original analysis plan. These details affect what can be concluded from a numerical comparison. The example is a reminder that statistical evidence is strongest when estimates are interpreted with their uncertainty and with transparent reporting of design and analysis decisions.

18. 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 leaves several trial-specific questions unanswered. It does not report the eligibility criteria, detailed participant characteristics, or the full definition of the population represented by the primary endpoint. Without those details, the degree to which the result applies to other groups of people with hip fractures cannot be determined from this record alone.

The primary endpoint is a composite of death and inability to walk 10 feet or across a room without human assistance. Component-specific primary results are not reported, so the contributions of mortality and walking ability cannot be separated. The outcome is assessed by telephone interview approximately 60 days after randomization, and longer-term primary results are not reported.

The overall enrollment is recorded as 1848, while the primary endpoint denominators are 712 and 733. The record does not explain this difference, and denominators vary for other outcomes as well. It does not report whether these differences reflect missing assessments, eligibility for particular measures, or another reason. No inference about attrition or the cause of incomplete outcome counts is warranted from the numbers alone.

The registry record identifies the trial as double-masked but does not describe who was masked or how masking was maintained. It also does not report the randomization procedure, analysis populations, missing-data methods, covariate strategy, or the original statistical analysis plan. These omissions limit assessment of potential bias and of whether the posted analyses followed prespecified methods.

Finally, the record does not report an equivalence margin, a clinically important difference, or a multiplicity strategy for secondary outcomes. Those missing details restrict claims about equivalence, clinical importance, and confirmatory interpretation of secondary findings.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Regional Versus General Anesthesia for Promoting Independence After Hip Fracture — NCT02507505.
• Registry record last updated 2024-05-13; status last verified 2023-12.
• Results first posted 2024-05-13.
• 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.

22. Record Summary

The registry record describes a completed, randomized, double-masked, parallel-group trial sponsored by the University of Pennsylvania, comparing regional anesthesia with general anesthesia for people with hip fractures. Enrollment is recorded as 1848; the study began in 2016-02, and primary completion was recorded in 2021-06.

The primary endpoint was death or inability to walk 10 feet or across a room without human assistance approximately 60 days after randomization. The posted risks were 0.185 for regional anesthesia and 0.180 for general anesthesia; the risk difference was -0.005, with a confidence interval from -0.045 to 0.035 and an unadjusted p-value of 0.794. The interval includes zero and does not establish equivalence.

The record lists secondary outcomes and adverse-event figures, but does not report a full statistical analysis plan, analysis-population definitions, missing-data handling, or a multiplicity strategy. The original sample-size assumptions are not reported in the registry record.