Improving Resilience and Longevity for Workers Through Exercise: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Improving Resilience and Longevity for Workers Through Exercise (NCT03050320), a randomized na study. The primary outcome is Change in Lower Extremity Functional Scale.

2. Clinical Question

The central outcome is change in self-reported function, not a direct measure of joint structure or a broad assessment of every aspect of health. The LEFS asks about difficulty with mobility tasks ranging from transfers to running. Higher scores represent better self-reported physical function. The study summary also describes mobility, pain, physical capacity, and resilience as areas of interest, including among workers without joint pain.

The registry record describes the study as randomized, single-masked, and parallel. It lists Exercise and No Exercise as the two interventions. The posted primary result is a comparison of mean changes in the two arms. The registry record does not report which participants or study personnel were masked, nor does it provide a more detailed account of eligibility criteria. The primary result therefore addresses the between-arm difference in LEFS change for the reported analysis, not the effect for every worker with osteoarthritis or for all workplace exercise programs.

3. Trial Design

The registry record identifies this as a randomized, single-masked, parallel-group trial. Participants were allocated to an Exercise arm or a No Exercise arm. The parallel design means the arms were compared over the same study period rather than participants crossing from one intervention to the other. The registry record does not report the method used to generate the random sequence, how allocation was concealed, or who was masked.

Enrollment was 43. The primary outcome results use 20 participants in the Exercise arm and 21 in the No Exercise arm. Participants in the Exercise arm were asked to attend 3 group classes per week for 12 weeks. Five class times were offered per week, and classes were taught by a certified exercise instructor. The description says classes included a warm-up, static poses shown to decrease knee joint loading, and a cool down including flexibility. The posted description ends mid-sentence, so further class details are not reported in the registry record.

The No Exercise arm was asked to refrain from changing physical activity over 12 weeks and to maintain usual strategies for managing knee or hip pain. This was an instruction to avoid changes, rather than a separately described active exercise program. The record lists the study as completed. Its start date was 2017-02-08 and its primary completion date was 2017-06-30.

The primary outcome was change in LEFS from Weeks 1 and 13. The registry lists 13 outcome measures and 12 secondary outcomes. It records no reported analyses. The trial's original statistical analysis plan, its intended analysis population, details of follow-up, and procedures for handling missing outcome data are not reported in the registry record. The listed phase is NA.

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.

Population: There were no cross overs.

6. Primary Endpoint

The registry lists the primary outcome as Change in Lower Extremity Functional Scale, measured over Weeks 1 and 13.

The primary endpoint is change in the Lower Extremity Functional Scale (LEFS) between Weeks 1 and 13. The LEFS consists of 20 items about difficulty with mobility tasks, ranging from transfers to running. Each item is scored from 0, meaning extreme difficulty or inability to perform an activity, to 4, meaning no difficulty. The total score can range from 0 to 80, and scores closer to 80 indicate better self-reported physical function.

A change score focuses on how a participant's reported function differs between the two assessment times. The reported arm summaries are mean changes, with standard deviations describing the spread of individual changes around each arm mean. Comparing the average changes between randomized arms is intended to distinguish the change observed under the exercise assignment from change observed under the no-exercise assignment. The numerical comparison does not by itself establish why any change occurred.

The registry description says the LEFS is reliable and valid in knee osteoarthritis and has superior sensitivity to change compared with similar measures. That makes it a relevant self-report measure for mobility-related function in this study. It remains a report of perceived difficulty, however, rather than a direct measure of performance on every activity named in the scale. The result pertains to the posted LEFS change and should not be treated as a finding about all pain, resilience, physical capacity, or work outcomes.

7. Results Posted in the Registry

• No Exercise: mean -1.60 versus 5.30 on control; difference -6.90 (95% CI -12.26 to -1.54), standardized effect d = -0.79; z-test p = 0.012.

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.

Change in Self-reported Upper Extremity Pain

• 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:
  • No Exercise: mean 0.20 versus -1.60 on control; difference 1.80 (95% CI -1.15 to 4.75), standardized effect d = 0.38; z-test p = 0.231.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between No Exercise and the control. The interval gives the range of effects that remain compatible with the data.

Change in Cardiovascular Fitness

• 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:
  • No Exercise: mean 0.10 versus 1.00 on control; difference -0.90 (95% CI -2.03 to 0.23), standardized effect d = -0.49; z-test p = 0.120.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between No Exercise and the control. The interval gives the range of effects that remain compatible with the data.

Change in Mobility Performance (Six-Minute Walk Test)

• 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:
  • No Exercise: mean 18.40 versus 36.80 on control; difference -18.40 (95% CI -44.47 to 7.67), standardized effect d = -0.44; z-test p = 0.167.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between No Exercise and the control. The interval gives the range of effects that remain compatible with the data.

The registry lists secondary domains that include self-reported knee and hip pain, upper-extremity pain, knee strength, grip strength, cardiovascular fitness, and mobility performance. Mobility assessments include the Six-Minute Walk Test, stair ascent and descent, and the 30-second Chair Stand Test. Together, these measures cover outcomes related to symptoms, strength, fitness, and task performance, complementing the primary self-reported function measure.

For the secondary comparisons with numerical estimates in the registry record, the confidence intervals include zero. The estimates do not provide the same clear separation from zero as the primary LEFS contrast. Their directions are not uniform across all measured domains, and the outcomes use different scales, so they should not be combined into a single overall effect. The primary result concerns self-reported lower-extremity function; it does not establish parallel changes in pain, fitness, strength, or performance.

Secondary findings generally carry less evidential weight when many outcomes are examined without a reported plan for addressing multiple comparisons. The more comparisons considered, the greater the opportunity for an apparently notable result to arise by chance. The registry record does not report a multiplicity adjustment or a hierarchy for interpreting secondary endpoints. The secondary results are therefore best treated as exploratory context rather than independent confirmation of the primary finding.

The record lists 12 secondary outcomes, while numerical comparison details are not reported for every listed domain in the available registry information. The study also records no reported analyses. The pattern across secondary outcomes should consequently be interpreted with caution: it offers a broad view of measured areas, but it does not provide a complete, prespecified synthesis of effects across all outcomes.

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

• Change in Self-reported Knee and Hip Pain
• Change in Self-reported Upper Extremity Pain
• Change in Isometric Knee Extensor and Flexor Strength
• Change in Grip Strength
• Change in Cardiovascular Fitness
• Change in Mobility Performance (Six-Minute Walk Test)
• Change in Mobility Performance (Stair Ascent and Descent)
• Change in Mobility Performance (30-second Chair Stand Test)

9. Statistical Interpretation

10. Statistical Methods Explained

The primary result is a comparison of mean change in a continuous outcome. The registry reports the mean and standard deviation of change for each arm, then a mean difference between arms. The comparison is an unadjusted re-calculation from the posted summary statistics. The registry record lists no reported analyses, and it does not describe the trial's original statistical analysis plan. The stated comparison should not be mistaken for a documented adjusted or prespecified sponsor analysis.

What does the mean difference represent?

The contrast is defined as No Exercise minus Exercise. The No Exercise mean change is -1.6 and the Exercise mean change is 5.3; the reported contrast is -6.9. The negative sign does not mean that the Exercise arm's change was negative. It reflects the order of subtraction. Since higher LEFS scores represent better function, a more positive change indicates improvement in self-reported function; under this contrast convention, a negative difference indicates the Exercise arm had the larger mean change.

Random allocation is intended to make groups comparable, on average, with respect to factors that could affect the outcome. That general property depends on how randomization and allocation were conducted and on what happened after assignment. The registry record identifies randomization but does not report the sequence-generation method, allocation concealment, adherence, or a detailed flow of participants. It is therefore not possible to assess those safeguards from the record alone.

What do standard deviations describe?

The standard deviation describes how spread out individual change scores are around the arm mean. It is not the standard error of the mean and it is not a confidence interval. In this trial, the reported primary standard deviations are 9.0 for Exercise and 8.5 for No Exercise. A standard deviation helps readers understand how much participant outcomes vary, but arm-level summaries do not show the distribution's shape or identify individual outcomes.

General statistical explanation: the standard error quantifies the sampling uncertainty of an estimate, while the standard deviation describes variability among observations. A larger standard error generally yields a wider confidence interval, all else equal. The registry reports standard errors for the arms in the comparison calculations, but the intended original method for constructing the trial's analysis is not reported.

How should the confidence interval be read?

The 95% confidence interval for the primary mean difference runs from -12.26 to -1.536. General statistical explanation: a confidence interval is a range of values generated by a method that, over repeated studies under its assumptions, would contain the target parameter at the stated rate. It conveys uncertainty around an estimate; it is not a range containing a specified proportion of individual participant changes. The interval's position relative to zero helps describe whether the data are compatible with no mean difference under the calculation used. It does not address bias, clinical importance, or whether the analysis was prespecified.

General statistical explanation: the unadjusted p-value describes how unusual data at least as discrepant as those observed would be under a null model of no difference, given the calculation's assumptions. It is not the probability that the null hypothesis is true, nor the probability that the result occurred by chance. The posted primary p-value is 0.012. The registry record does not report whether that value was adjusted for other endpoints or analyses, so it is described as unadjusted.

Why does over-dispersion matter?

General statistical explanation: over-dispersion occurs when observed variability is greater than a model expects. If a method assumes less variability than the data contain, it can understate uncertainty and make intervals too narrow. For a continuous outcome, the reported standard deviations provide information about spread, but the registry record does not report a distributional assessment or a specific model used in the original analysis. No claim about over-dispersion can be made from these summaries alone.

Mean-based comparisons are often useful when the scientific question concerns average change. Their interpretation can be sensitive to skewness, unusual values, and the distribution of outcomes, particularly when groups are small. A mean difference also does not reveal whether a similar shift occurred across participants or whether the mean reflects a mixture of different patterns. The posted summary statistics cannot answer those questions.

What is not established by the statistical record?

The registry record does not report the original statistical plan, whether the primary endpoint and analysis were specified before results were examined, or how missing observations were handled. It does not state whether the comparison adjusted for baseline LEFS or other covariates, or identify an intention-to-treat, per-protocol, or other analysis population. No adjustment for multiplicity is reported. These omissions limit assessment of the full analysis process. They do not change the arithmetic meaning of the posted unadjusted contrast, but they restrict how confidently it can be interpreted as the trial's definitive analysis.

General statistical explanation: a valid interpretation depends not only on the estimated difference and its precision, but also on design, measurement, follow-up, model assumptions, and the analysis choices made. An interval can quantify sampling uncertainty under a calculation while leaving systematic error and missing-data bias unresolved. Readers should keep those distinct forms of uncertainty separate.

11. Confidence Intervals and Precision

The primary mean difference is -6.9, with a 95% confidence interval from -12.26 to -1.536. The interval gives a range of estimates compatible with the posted calculation and its assumptions. It is entirely below zero. Under the No Exercise minus Exercise convention, negative values correspond to a larger mean LEFS change in the Exercise arm. The interval's width also shows that the estimate is not exact: values nearer either endpoint remain compatible with the data under the interval procedure.

The confidence interval is more informative about precision than the point estimate alone. The point estimate is the single best estimate from the posted comparison; the interval describes sampling uncertainty around it. It does not account for uncertainty due to possible missing data, measurement limitations, selective reporting, or unreported analysis choices. The registry record does not report enough information to evaluate those sources of uncertainty.

The comparison uses 20 participants in the Exercise arm and 21 in the No Exercise arm. The primary standard deviations are 9.0 and 8.5. With a modest number of observations and individual variation, the mean difference remains an estimate of an underlying group contrast rather than a precise description of every participant's experience. The record does not report a clinically important difference threshold for the LEFS, so the interval cannot be classified against such a threshold from the registry information.

A confidence interval that excludes zero is not by itself evidence that an effect is important, unbiased, or reproducible. Nor does the interval indicate the probability that the true effect lies in the particular range. It expresses statistical precision conditional on the method and assumptions. The trial's original interval method is not reported in the registry record; the posted comparison is an unadjusted re-calculation from summary statistics.

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 for a two-arm comparison. They are not total event counts: the event-count convention applies to time-to-event outcomes, while this is a continuous outcome. The planning illustration assumes a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It uses the stated fraction of the observed effect as the effect to detect.

The 80% power column gives the approximate participants per arm for a design with an 80% chance of detecting the specified effect under those assumptions, if that effect is the true one. The 90% power column describes the corresponding planning target for a 90% chance. These are design calculations, not statements about what happened in the completed trial. The trial's original sample-size justification and design assumptions are not reported in the registry record.

The scenarios consider planning for 100%, 75%, and 50% of the observed effect. The smaller the effect a future study is designed to detect, the more participants per arm it generally needs, all else equal. This is why the displayed participant requirements rise as the assumed effect becomes smaller. The illustration uses the observed result as its reference, so it should be treated cautiously: an observed effect from a small trial can be an uncertain basis for planning a later study.

This is not observed power. It is a planning illustration based on stated assumptions, not a retrospective measure of whether the completed trial had a particular probability of finding its result. The figures do not demonstrate that the trial was adequately or inadequately designed, because its own planning assumptions are not reported.

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 = -6.900; pooled standard deviation σ = 8.747.
2. n = 2 × (1.96 + 0.842)² × 8.747² / -6.900² = 25.2, rounded up to 26 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 <- -6.9                      # observed difference in means
sigma <- 8.74716071150065                     # 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(3050320)
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 = 26 (80% power), 34 (90% power)
 75% of observed effect: n per arm = 45 (80% power), 61 (90% power)
 50% of observed effect: n per arm = 101 (80% power), 136 (90% power)
power.t.test: 26.2 
Simulated power at n = 26 per arm: 0.796 (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. Multiplicity, Missing Data and Analysis Populations

The registry record lists a primary endpoint and multiple secondary outcomes, but it does not report how multiplicity was handled. Multiplicity arises when several outcomes or statistical comparisons are examined. General statistical explanation: as the number of opportunities to identify a result increases, so does the chance of at least one apparently unusual finding under a collection of null effects. Methods such as prespecified outcome hierarchies or adjustment procedures can address this concern, but the record does not say whether either was used.

The posted p-value for the primary comparison is unadjusted. The registry record does not report whether the primary endpoint was designated in advance in a protocol or analysis plan, whether additional analyses were conducted, or how the secondary outcomes were prioritized. It also records no reported analyses. These gaps mean that the reader cannot determine from the registry whether the posted endpoint represents the full set of analyses or how the investigators intended to interpret multiple results.

Missing-data procedures are also not reported. The primary outcome summaries use 20 participants in Exercise and 21 in No Exercise, while enrollment was 43. The reason for this difference is not reported in the registry record. It is not possible to tell whether outcome observations were missing, whether participants were excluded from a particular analysis, or whether the counts reflect another reporting convention. No imputation method, sensitivity analysis, or follow-up accounting is described.

The record does not identify an intention-to-treat, per-protocol, or other analysis population. It also does not report how adherence to the exercise classes was assessed or how participants who changed activity were handled. These details matter because analysis population and missingness can affect the interpretation of a randomized comparison. The posted mean differences remain descriptive of the reported arm summaries, but the record does not establish how closely those summaries reflect all randomized participants.

General statistical explanation: randomization supports causal interpretation when assignment is preserved in the analysis and post-randomization differences, attrition, and outcome measurement do not introduce important bias. Without information on participant flow, missing outcomes, and analysis choices, those conditions cannot be fully assessed from the registry record. This limitation is separate from the sampling uncertainty represented by the confidence interval.

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.

The registry reports serious adverse events for 21 participants at risk in the Exercise arm and 22 at risk in the No Exercise arm. It records 0 serious adverse events affecting participants in either arm and 0 deaths in either arm. These are the serious-event figures reported for the groups; they do not establish that no other types of health events occurred.

The registry also records 0 other adverse events affecting participants among 21 at risk in Exercise and among 22 at risk in No Exercise. No serious-event terms are listed. The outcome and safety counts are not identical: the primary LEFS summaries use 20 and 21 participants, while the adverse-event record uses 21 and 22 at risk. The registry does not explain the difference.

Zero reported events should be read as no events recorded in these groups, not as proof that an intervention carries no risk. With a limited number of participants, uncommon events may not be observed. The registry record does not report detailed event definitions, surveillance procedures, or exposure-adjusted analyses. These figures describe the posted safety reporting and do not support broader conclusions about safety beyond the study.

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

The primary result is an unadjusted comparison of mean LEFS change from Weeks 1 and 13. The Exercise arm's mean change was 5.3, compared with -1.6 in the No Exercise arm. The No Exercise minus Exercise difference was -6.9, with a 95% confidence interval from -12.26 to -1.536. Since higher LEFS scores indicate better self-reported function, the estimate is consistent with greater average improvement in the Exercise arm during the study period.

This result does not show that every participant improved, or that the same change would occur for every worker with knee or hip osteoarthritis. The arm means summarize groups and conceal individual variation. The standard deviations, 9.0 and 8.5, describe that variation but do not identify who improved or by how much. The registry record also includes workers with no joint pain in the study summary, and the primary outcome result does not separately report results by condition or pain status.

The estimate does not establish the size of a clinically important benefit. The registry record gives the LEFS scale range and interpretation, but it does not report a threshold for meaningful change. The confidence interval quantifies sampling uncertainty under the calculation; it does not resolve uncertainty from missing outcomes, possible selection, measurement, or analysis choices. Those matters are not reported in the registry record.

Nor does the LEFS finding establish effects on all the other study aims. Pain, strength, cardiovascular fitness, and mobility performance are distinct outcomes. Available numerical secondary comparisons have intervals that include zero, and the registry record does not report a multiplicity strategy. The primary result should not be generalized to all those outcomes, to exercise programs delivered outside this workplace context, or to periods beyond the assessment described.

The appropriate reading is limited: the posted data show a difference in mean self-reported LEFS change between the two assigned arms, with an interval that excludes zero under the unadjusted calculation. The record does not provide enough detail to settle the full analysis plan, missing-data handling, or clinical importance of the estimated difference.

17. Why This Trial Matters Statistically

This trial is statistically instructive because it links a familiar randomized comparison to an outcome that is a mean change on a continuous scale. The sign of the mean difference depends on the subtraction order, so readers must connect the contrast definition to the score direction. Here, higher LEFS scores indicate better function, while the comparison is No Exercise minus Exercise; the negative estimate therefore corresponds to a larger mean change in the Exercise arm.

The primary confidence interval is also a useful reminder that a point estimate and its precision are different pieces of information. The estimate is -6.9, while its 95% confidence interval ranges from -12.26 to -1.536. Reading the estimate without the interval would hide the range of uncertainty; reading the interval without the scale direction would obscure the interpretation. Neither alone addresses the clinical meaning of the change.

The record also illustrates the gap between a trial's posted outcome summaries and a complete statistical account. Randomization and a primary endpoint are identified, but the original analysis plan, missing-data procedures, analysis population, and multiplicity handling are not reported. Those omissions matter when assessing whether a result is prespecified and how it fits with secondary findings. A numerical result can be interpreted correctly as an unadjusted group contrast while still leaving important design and analysis questions unanswered.

Finally, planning figures based on observed effects need a different interpretation from observed trial outcomes. They illustrate how assumed effect size and power targets relate to planned participants per arm under stated assumptions. They do not describe the probability that the completed trial found its result, and they do not substitute for the trial's unreported original sample-size rationale.

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 primary outcome summaries cover 20 participants in Exercise and 21 in No Exercise, compared with total enrollment of 43. The registry does not explain the difference or report participant flow, so the extent and handling of missing outcome information cannot be determined. The analysis population is not specified, and adherence to the requested exercise schedule is not reported.

The record identifies a single-masked design but does not say who was masked or how masking was maintained. It also does not report the randomization method or allocation concealment. The exercise description is truncated after mentioning a cool down including flexibility, so the full content of the classes is not available. The no-exercise instructions are described, but compliance with them is not reported.

The primary result is an unadjusted comparison calculated from posted summary statistics. The trial's original statistical analysis plan, covariate adjustments, and method for constructing the original analysis are not reported. There is no reported multiplicity approach despite multiple secondary outcomes, and no detailed results are available for every secondary domain listed. The registry also does not report a clinically important LEFS change threshold.

The primary result concerns mean change at the assessment times recorded, rather than longer-term outcomes. Follow-up beyond Weeks 1 and 13 is not reported. The sample is described as workers with knee or hip osteoarthritis and workers without joint pain, but the registry does not provide the primary result separately for those groups. These limitations restrict assessment of the result's precision, completeness, and applicability beyond the reported comparison.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Improving Resilience and Longevity for Workers Through Exercise — NCT03050320.
• Registry record last updated 2018-08-10; status last verified 2017-11.
• Results first posted 2018-08-10.
• 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, single-masked, parallel-group study of workplace exercise for workers with knee or hip osteoarthritis and workers with no joint pain. Enrollment was 43. The Exercise arm was asked to attend group classes for 12 weeks, while the No Exercise arm was asked to avoid changing physical activity.

The primary outcome was change in LEFS from Weeks 1 and 13. Mean change was 5.3 in Exercise and -1.6 in No Exercise; the No Exercise minus Exercise mean difference was -6.9, with a 95% confidence interval from -12.26 to -1.536 and an unadjusted p-value of 0.012. The registry record lists 12 secondary outcomes, reports no analyses, and does not report the original analysis plan, missing-data procedures, or multiplicity handling.