Biweekly Schedule of Docetaxel and Cisplatin in High Risk Patients With Unresectable Non-small Cell Lung Cancer (NSCLC): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Biweekly Schedule of Docetaxel and Cisplatin in High Risk Patients With Unresectable Non-small Cell Lung Cancer (NSCLC) (NCT00995761), a na phase 2 study. The primary outcome is Response Rates Confirmed With CT or MRI.

2. Clinical Question

The study focused on a treatment schedule rather than a randomized comparison. Its background describes uncertainty about the dose and schedule of docetaxel and cisplatin, and notes concerns about toxicities with other schedules. The record’s primary endpoint is tumor response, not a direct comparison of survival or safety between treatment regimens.

The registry lists time to progression and overall survival as secondary outcomes to be confirmed through follow-up and observation after treatment. It does not report those outcome results. Nor does it give a comparison with a different schedule or a control group. As a result, the central question addressed by the design is descriptive: what responses were observed among participants receiving this biweekly schedule? The registry record does not provide the response percentage needed to answer that question numerically.

3. Trial Design

This was a phase II, single-group study sponsored by Gyeongsang National University Hospital. The registry lists an enrollment of 48 participants and identifies the intervention as docetaxel and cisplatin. The study is marked completed. Its start is recorded as 2009-10 and its primary completion as 2012-08.

The intervention was administered on a biweekly schedule within repeating 4-week periods: docetaxel 40mg/m2 on day 1 and day 15, and cisplatin 40mg/m2 on day 1 and day 15. The registry describes no masking. Allocation is recorded as NA, consistent with the single-group design. There is no randomized control arm in the record, so results cannot be interpreted as a head-to-head estimate against another schedule or treatment.

The primary outcome was response rate, assessed after every 2 cycles of treatment. The registry describes imaging assessment using RECIST v1.0, with CT or MRI mentioned in the outcome title and MRI specified in the endpoint description. The secondary outcomes were time to progression and overall survival, assessed through follow-up and observation after treatment.

The record says that sample size was calculated according to Simon's two-stage optimal design. It does not report the design’s response-rate thresholds, stage-specific enrollment rules, stopping criteria, or other numerical assumptions. It states that statistical evaluation used an ITT analysis and that descriptive statistics were reported as proportions and medians. Details beyond those statements, including the precise analysis populations for each outcome, 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: not specific problems

Overall Study

Analysis population for the primary outcome, as defined in the registry: The sample size was calculated according to Simon's two-stage optimal design.The statistical evaluation was performed based on an ITT analysis. Descriptive statistics are reported as proportions and medians. OS and TTP were assessed by the K-M method, and the 95% CI for the median time to events was computed.

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 Response Rates Confirmed With CT or MRI, measured over after every 2 cycles of docetaxel and cisplatin.

The primary endpoint is the percentage of participants with a tumor response, assessed after every 2 cycles of docetaxel and cisplatin. The endpoint description defines overall response as complete response (CR) plus partial response (PR). Under RECIST v1.0, CR means disappearance of all target lesions; PR means a decrease of at least 30% in the sum of the longest diameters of target lesions. The registry describes assessment by imaging and names CT or MRI in the outcome title.

Response rate is a binary summary at the participant level: each participant is classified according to whether they meet the response definition. Reporting the percentage makes the observed frequency understandable, while a confidence interval can communicate uncertainty around that estimate. This is a general statistical explanation; it does not establish how many participants responded in this study.

Tumor response is used to describe whether measurable disease has decreased according to prespecified imaging criteria. It is not the same outcome as time to progression or overall survival, which the registry lists separately as secondary outcomes. The response percentage and its 95% confidence interval are not reported in the registry record, so the magnitude and precision of the primary endpoint cannot be read from the posted results.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a single-group phase II design describe?

A single-group study follows participants receiving one intervention and describes outcomes in that group. Here, the registry identifies a phase II study with an enrollment of 48 and no separate comparator. The design can document the observed response and safety experience under the stated schedule, if those results are reported. It does not, by itself, provide a randomized estimate of how outcomes differ from another regimen. General statistical context: a between-group treatment effect requires a comparison, while a single-group percentage is a description of the participants observed under that study’s conditions.

The registry says the sample size was calculated according to Simon's two-stage optimal design. This is a general type of phase II planning approach that can specify a staged enrollment and decision rules based on response. The particular response assumptions and decision thresholds are not reported in the registry record. It is therefore not possible to reconstruct the intended operating characteristics or determine what response pattern would have led to a particular study decision.

What does the response percentage measure?

The endpoint is the percentage of participants with a complete or partial response after every 2 cycles. The outcome description defines CR as disappearance of all target lesions and PR as a decrease of at least 30% in the sum of the longest diameters of target lesions. The response category is assessed according to RECIST v1.0. The registry describes repeated clinical and laboratory assessments during treatment and imaging every two cycles to assess response, with earlier imaging if required to document progression.

For a binary endpoint, a participant contributes to the response category or does not. A percentage summarizes the share classified as responders, but its interpretation depends on how the analysis handles participants without an evaluable assessment. The record states that statistical evaluation used an ITT analysis, but does not report the response numerator, denominator used for the estimate, or detailed handling of missing response assessments. The response percentage and 95% confidence interval are not reported.

Why is a confidence interval useful?

In general, a confidence interval expresses uncertainty around an estimate under a specified statistical method. It is not a guarantee that the true value lies inside the particular interval, nor does it establish clinical importance. Its width is influenced by the amount of information and the observed data, among other factors. The registry names a 95% confidence interval for the primary response outcome but does not post its value. Without the estimate and interval, the result’s precision cannot be assessed.

How are time-to-event outcomes different?

The registry lists time to progression (TTP) and overall survival (OS) as secondary outcomes and states that they were assessed by the Kaplan–Meier method. In general, Kaplan–Meier estimation uses the timing of events and accounts for participants whose event time is not observed before follow-up ends or who are otherwise censored. The resulting curve represents estimated event-free probability over time, subject to the assumptions and quality of follow-up data. The registry also mentions 95% confidence intervals for median times to events, but the record’s methods description is incomplete and the secondary outcome results are not reported.

Time-to-event analyses depend on clear definitions of the event, the time origin, and censoring. The registry names TTP and OS but does not provide enough detail to assess those elements fully. It does not state the event counts, follow-up duration, median estimates, or confidence intervals. Accordingly, no numerical interpretation of these outcomes is possible from the posted record.

What does over-dispersion mean in general?

Over-dispersion is a general concern for some count-data models when observed variability exceeds what the model assumes. It can make standard errors too small if ignored, leading to confidence intervals that are too narrow and tests that appear more certain than warranted. The primary outcome in this study is described as a percentage of participants with an event, rather than a count-rate model, and the registry does not report use of an over-dispersion adjustment. This concept does not establish that over-dispersion was present or relevant to the study’s posted analyses.

What can planning illustrations establish?

Sample-size illustrations based on an observed effect are planning scenarios, not observed trial outcomes and not a measure of the probability that the study detected a real effect. The registry’s own design description refers to Simon's two-stage optimal design, whereas the planning assumptions describe hypothetical two-arm calculations with equal allocation and a normal approximation. Those illustrations do not change the study’s actual single-group design. No numerical sample-size illustration is repeated because the registry record does not give the observed response estimate needed to interpret such a scenario alongside the clinical result.

In general, a planning calculation depends on assumptions about the target effect, significance level, power, allocation, and statistical model. Changing those assumptions changes the resulting planning requirement. Such calculations should not be described as observed power, and they do not compensate for absent outcome estimates. For this study, the posted registry record does not provide enough response-result information to connect a planning scenario to an observed clinical endpoint.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Biweekly Schedule of Docetaxel and Cisplatin")
n      <- c(48)
events <- c(31)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Biweekly Schedule of Docetaxel and Cisplatin  48  31  64.6  49.5  77.8  50.4  76.6  50.4  76.6

11. Multiplicity, Missing Data and Analysis Populations

The registry identifies response rate as the primary outcome and lists time to progression and overall survival as secondary outcomes. It does not report a multiplicity adjustment or describe a hierarchy of testing across these outcomes. In general, testing several outcomes can increase the chance of at least one apparently notable result under a null hypothesis. Whether an adjustment is appropriate depends on the intended claims and analysis plan. Since no outcome results or complete statistical plan are posted, the impact of multiplicity on interpretation cannot be assessed.

The record states that statistical evaluation was based on an ITT analysis. In general, an intention-to-treat approach aims to analyze participants according to their assigned study group, preserving the comparison created by randomization. This trial has a single group and no randomized allocation, so the record’s ITT statement does not create a comparison group. The exact operational definition of the analysis population and its application to each endpoint are not reported in the registry record.

Missing outcome data can affect a response percentage if participants do not have an evaluable assessment. The registry does not describe the number of participants with missing response assessments, how such cases were classified, or whether any sensitivity analyses were conducted. The missing-data approach for TTP and OS is also not reported in sufficient detail to assess censoring practices.

The record does not report interim analyses, a full statistical analysis plan, or details of any adjustments for multiple looks at the data. These items should not be inferred from the phase II label or from the statement about Simon's two-stage design. Without the outcome values, analysis-population details, and missing-data methods, readers cannot independently evaluate the robustness of the posted endpoint estimates.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: anemia (14.6%), diarrhea (10.4%), infection (10.4%), leukopenia (8.3%), neutropenia (6.2%).

The registry lists 48 participants at risk in the biweekly schedule group and 7 affected in the serious adverse events figure. It also lists 48 at risk and 0 affected in the other adverse events figure. The record provides no death count; deaths are not reported in the registry record.

The listed serious adverse event terms and percentages are anemia, 14.6%; diarrhea, 10.4%; infection, 10.4%; leukopenia, 8.3%; neutropenia, 6.2%; and asthenia, 6.2%. These are descriptive entries, not a comparison with a different treatment schedule. The record does not clarify whether participants could contribute to more than one term, so the percentages should not be added together or read as mutually exclusive categories.

Serious adverse events are distinct from all adverse events. The listed term percentages should not be interpreted as the total frequency of every symptom or laboratory abnormality. The registry does not give event timing, duration, severity grades for each term, relationship to treatment, or participant-level detail. The figures therefore offer a limited description of recorded serious events rather than a complete safety profile.

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

The registry record supports a clear description of the study’s question and design: a phase II, single-group evaluation of docetaxel and cisplatin on a biweekly schedule in 48 participants with unresectable NSCLC. It defines a primary response endpoint using RECIST v1.0, with assessment after every 2 cycles, and lists TTP and OS as secondary outcomes. These details establish what the study set out to measure and how the schedule was given.

However, the record does not report the primary response percentage or its 95% confidence interval. It also does not report numerical results for the secondary outcomes. Consequently, it is not possible to state the observed response frequency, judge the precision of that estimate, or describe the survival outcomes from this registry record. The missing estimates are not evidence that no responses or events occurred; they mean the registry does not report those results.

The single-group design also limits what any observed outcome could establish. A response percentage in one group does not quantify a difference from a three-weekly schedule, weekly schedule, or other treatment. Without randomization and a concurrent comparison group, differences from other settings could reflect differences in participants, treatment delivery, assessment, or follow-up rather than the schedule itself.

The record includes selected serious adverse event figures, but those figures do not supply a complete accounting of safety or a comparative assessment. The event terms and percentages should be read as descriptive registry entries, with the limitations of missing detail about timing, severity, relatedness, and overlap.

In short, the registry describes a treatment schedule, a response definition, and selected analysis methods. It does not provide the outcome estimates needed to assess response magnitude, precision, or time-to-event results. It therefore supports description of the study’s structure, not a quantitative conclusion about comparative benefit or the full safety profile.

14. Why This Trial Matters Statistically

This study is statistically interesting because its registry record combines a single-group phase II design with a stated Simon two-stage sample-size design. Simon's two-stage optimal design is, in general, a way to plan a phase II study with staged enrollment and decision rules based on response. Yet the registry does not provide the response assumptions, stage boundaries, or stopping criteria. That gap illustrates why naming a design method is not enough to reproduce its planning logic or assess its operating characteristics.

The distinction between the trial design and planning illustrations is also important. The trial itself is single-group, with allocation recorded as NA. Any hypothetical two-arm sample-size illustration is not a feature of the observed design and cannot be treated as a comparison made in the study. Planning requirements are conditional on assumptions; they are not observed outcomes or retrospective proof of power.

The endpoint also highlights the role of reporting. A response definition can be specified precisely, but the definition alone cannot reveal the number of participants who met it or the uncertainty around that number. With no response estimate or confidence interval in the registry record, readers cannot connect the method to a quantitative result.

Finally, the study illustrates the limits of interpreting single-group data. Descriptive response and safety information can characterize a treated group, while claims about differences between schedules require a suitable comparison. The posted record states enough to identify the intended statistical framework, but not enough to evaluate response precision, time-to-event findings, or comparative effects. That separation between design description and accessible results is central to careful clinical-trial interpretation.

15. 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 most immediate limitation is that the registry record does not report the primary response percentage or its 95% confidence interval. It also gives no numerical results for TTP or OS. The study’s central efficacy outcomes therefore cannot be evaluated quantitatively from the posted record.

The single-group design has no randomized comparator. It can describe outcomes among participants receiving the biweekly schedule, but cannot estimate a randomized difference from another schedule or treatment. The registry also does not report the eligibility criteria in detail, despite describing the participants as high risk, so the scope of the population represented is not fully clear.

Several design and analysis details are absent. Although the record says sample size was calculated according to Simon's two-stage optimal design and that evaluation used an ITT analysis, it does not state the design thresholds, stage rules, analysis-population details, or response handling for missing assessments. It does not report whether interim analyses or multiplicity procedures were used. The endpoint description and statistical-method statement therefore do not amount to a complete analysis plan.

For the secondary time-to-event outcomes, the record does not give event counts, follow-up summaries, median estimates, confidence intervals, or sufficient detail about event definitions and censoring. Safety reporting is also limited: selected serious adverse event terms are listed, but information about timing, duration, grade, relationship to treatment, and participant-level overlap is absent. The record does not report a death count.

These limitations concern what can be learned from the registry record; they do not establish that additional analyses or records do not exist elsewhere. They do mean that the posted information is insufficient for a complete assessment of efficacy, precision, follow-up, or safety.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Biweekly Schedule of Docetaxel and Cisplatin in High Risk Patients With Unresectable Non-small Cell Lung Cancer (NSCLC) — NCT00995761.
• Registry record last updated 2014-03-03; status last verified 2014-02.
• Results first posted 2014-03-03.
• 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.

19. Record Summary

NCT00995761 is a completed phase II, single-group study sponsored by Gyeongsang National University Hospital, with enrollment listed as 48. It examined docetaxel 40mg/m2 and cisplatin 40mg/m2 on day 1 and day 15 of every 4 weeks in participants with unresectable NSCLC.

The primary outcome was response rate after every 2 cycles, assessed using RECIST v1.0. The registry says sample size was calculated according to Simon's two-stage optimal design and that statistical evaluation used an ITT analysis. TTP and OS were listed as secondary outcomes.

The registry record does not report the primary response estimate, its 95% confidence interval, or numerical secondary outcome results. It lists selected serious adverse event terms and percentages, but does not provide a full safety account. The single-group design does not provide a randomized comparison with another schedule.