Identifying and Treating Depression in Hemodialysis Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Identifying and Treating Depression in Hemodialysis Patients (NCT03390933), a na phase 4 study. The primary outcome is To Determine the Impact of Directly Observed Weekly Fluoxetine Treatment on Remission of Depression Among Hemodialysis Patients..

2. Clinical Question

3. Trial Design

This is a completed, single-group Phase 4 clinical trial registered as NCT03390933. The registry lists MetroHealth Medical Center as sponsor, an enrollment of 16, no masking, and allocation as not applicable. The intervention is fluoxetine. The listed study dates are 2018-03-01 for study start and 2023-02-28 for primary completion.

The study summary describes a broader project with a cross-sectional Phase 1 followed by a single-arm clinical trial in Phase 2 at 17 dialysis facilities. It says Phase 1 was intended to assess depressive symptoms, dialysis-related complications, anxiety, and quality of life in about 1083 patients. The intervention description says approximately 96 patients would be enrolled in the Phase II fluoxetine group over the duration of the entire study. These are described plans; the registry lists actual enrollment as 16.

The single-group design means the record does not provide a randomized control group for comparison. As a result, the registered study structure does not separate changes associated with fluoxetine from changes that could arise over time or from other influences. The record lists no masking and does not identify a control intervention.

The registry identifies the primary outcome as depression remission at week 12, while its reported timeframe is 3 years. It does not explain how the week 12 outcome relates to that timeframe. The rationale for the planned sample size, details of the treatment schedule beyond weekly directly observed treatment, and the 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: Screened Via Chart Abstraction 1588 In person Screening Conducted 1248 Evaluated for Major Depression Disorder 110 Untreated for Major Depressive Disorder 27 Consented/enrolled into trial 16

Overall Study

Analysis population for the primary outcome, as defined in the registry: Enrolled 16 * 13 Female * 13 African American * 1 Hispanic

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 To Determine the Impact of Directly Observed Weekly Fluoxetine Treatment on Remission of Depression Among Hemodialysis Patients., measured over 3 years.

The stated primary endpoint concerns remission of depressive symptoms measured with the Patient Health Questionnaire 9 (PHQ-9). The instrument has 9 questions about how often a participant has experienced depressive symptoms over the last 2 weeks. Each question uses a 0-3 response scale, and the registry gives a total-score range of 0min to 27max. It defines remission as a week 12 total score below 5 and notes that a score of ≥10 is an established threshold for clinically relevant depressive symptoms.

A threshold-based definition makes the intended clinical state explicit: participants are classified according to whether their score falls below the remission cutoff. However, the registered outcome is also described as a continuous measure summarized by a mean and standard deviation. The record does not clarify whether the planned primary analysis was to compare mean PHQ-9 scores, the proportion meeting the remission threshold, or both. That distinction matters because a mean describes the group’s average score, while a remission proportion describes how many participants meet a defined criterion.

The registry record does not report the observed week 12 PHQ-9 scores, the number meeting the remission definition, or a treatment-effect estimate. The reason for choosing this endpoint beyond its stated focus on remission is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What the design can estimate. The trial is registered as single-group, with no masking and no randomized comparison. In general, a single-group study can describe outcomes among participants who received the intervention, but it cannot directly estimate the contrast between intervention and control groups when no control group is included. If scores were collected over time, a within-group change could describe how participants’ scores differed across assessments. It would not, by itself, distinguish an intervention effect from natural change, concurrent care, or other influences. The registry record does not report the actual primary outcome analysis or a statistical plan for handling this design.

Mean scores and remission classification. The registered endpoint is described as a continuous measure summarized by a mean and standard deviation, while its definition identifies remission using a PHQ-9 score below 5 at week 12. In general, a mean uses the scale’s numerical values to describe the group’s average score, and a standard deviation describes variability around that average. A remission classification instead counts participants who meet the stated cutoff. Neither summary fully substitutes for the other: a group mean does not reveal how many participants crossed the threshold, and a remission count does not show the distribution of scores within the group. The registry record does not state whether the analysis used the continuous score, the threshold classification, or both.

Confidence intervals and uncertainty. In general, a confidence interval expresses the range of values compatible with an estimate under a specified statistical procedure. A narrow interval indicates greater precision than a wide interval, while neither interval width nor statistical significance alone establishes clinical importance or causation. No confidence interval, standard error, p-value, or primary outcome estimate is reported in the registry record. The precision of the remission estimate therefore cannot be assessed from the posted results.

Planning illustrations. The stated sample-size assumptions describe a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the target effect is expressed as a fraction of the observed effect. Such calculations are planning tools, not observed trial outcomes or observed power. The record characterizes non-time-to-event sample sizes as participants per arm and time-to-event calculations as total events. However, the trial itself is single-group, and the registry record does not report a control arm or the trial’s own sample-size justification. The assumptions behind a two-arm illustration should not be mistaken for the design actually registered.

Distributional assumptions. A normal approximation is a general mathematical simplification used in some calculations. Whether it is suitable depends on the outcome and analysis. For a continuous score, the distribution of participant scores and the way repeated observations are handled can matter. For a threshold outcome such as remission, the analysis would concern a proportion rather than a mean. The registry record does not report diagnostic checks, model details, or an approach to possible departures from assumptions. Over-dispersion is a general concern when observed variation exceeds what a model expects; whether it is relevant to an analysis of this outcome cannot be determined because no model is described.

Interpretation of statistical tests. In general, a p-value measures how compatible observed data are with a specified null model under the assumptions of the test. It does not measure the probability that a treatment works, and it does not communicate the size or precision of an effect on its own. No p-value or test result for the primary endpoint is reported in the registry record. The listed count of analyses is 0, so the posted record does not give a primary analysis result to interpret.

What is missing from the analysis description. The registry record does not report how baseline scores were used, whether follow-up scores were analyzed among all enrolled participants or only those with observed outcomes, how missing assessments were handled, or whether any covariates were included. It also does not report an interim-analysis plan, a detailed statistical analysis plan, or a sample-size justification. These omissions prevent reconstruction of the intended inferential procedure from the record alone.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Fluoxetine Group")
n   <- c(16)
m   <- c(6.6)
sp  <- c(2)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Fluoxetine Group  16  6.600  2.000  5.534  7.666

11. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when an analysis tests or estimates several outcomes, time points, subgroups, or treatment contrasts. In general, making many statistical comparisons can increase the chance of finding an apparently notable result by chance unless the analysis plan addresses that issue. The registry lists one outcome measure and 0 analyses, but the record does not provide an analysis plan specifying which outcome form, time point, or tests were intended as primary. A multiplicity adjustment strategy is not reported in the registry record.

The endpoint description refers to remission at week 12 and also lists a 3 years timeframe. The record does not explain whether other time points were analyzed or how any repeated assessments were handled. It likewise does not report whether subgroup analyses were planned. Without that information, the scope of the intended comparisons and any multiplicity strategy cannot be determined.

Missing-data methods are also not reported in the registry record. The posted information does not state how many participants had a week 12 PHQ-9 assessment, whether any participants discontinued or missed assessments, or how missing scores were treated. It does not describe imputation, complete-case analysis, or sensitivity analyses. No analysis population is specified, such as an intention-to-treat or per-protocol population.

These omissions matter because an outcome estimate can depend on which participants contribute data and how missing assessments are handled. They also limit assessment of whether the reported enrollment and the analyzed population would match. The registry record does not report the details needed to evaluate these issues.

12. 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 1% reporting threshold.

Most frequent non-serious adverse event terms

The registry lists 16 participants at risk in the Fluoxetine Group for serious adverse events and 0 affected. It also lists 16 participants at risk for other adverse events and 1 affected. The death count is 0. No serious adverse event terms are listed.

These are counts in the posted safety record. They do not describe the type, timing, duration, or severity of the other adverse event, and the registry record does not provide further detail about it. The serious-event count and the other-adverse-event count are separate categories; the one participant listed as affected by an other adverse event should not be treated as a serious adverse event based on this record.

In general, a count of zero recorded events is not evidence that an event is impossible, and safety counts from a single-group study do not provide a comparative estimate against an untreated or control group. The record does not report additional safety analyses or a detailed account of adverse-event collection and attribution. These figures should therefore be read as the counts reported for this study, not as a comparative safety assessment.

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

The registry record describes a study of directly observed weekly fluoxetine in hemodialysis patients, with depression remission defined using a week 12 PHQ-9 score below 5. It reports enrollment of 16 and safety counts, but does not report the primary outcome results. There is no reported remission count, mean PHQ-9 score, change from baseline, confidence interval, or statistical test result in the registry record.

That absence limits what can be concluded from the posted information. It does not show that participants did or did not reach remission, and it does not establish whether scores improved, worsened, or remained similar. The record also cannot quantify the precision of an outcome estimate when no estimate or uncertainty interval is reported.

The design further restricts interpretation. A single-group study without a randomized comparator can describe outcomes in the treated group, but it cannot provide a direct randomized estimate of how those outcomes differ from what would have happened under a control condition. No masking is listed. Thus, even if outcome values were reported, the design would need to be considered when interpreting whether changes could be attributed to the intervention.

The registry’s outcome description also leaves an analysis ambiguity: remission is defined by a threshold, while the measure is characterized as a continuous mean and standard deviation. The record does not clarify which summary or test was used. It does not report how missing outcome assessments, analysis populations, or multiple analyses were handled.

The appropriate reading is limited to the information recorded: the study was completed, enrolled 16 participants, named a week 12 PHQ-9 remission endpoint, and reported the listed safety counts. The effectiveness and precision of the primary outcome are not reported in the registry record. No treatment recommendation or causal conclusion follows from these entries alone.

14. Why This Trial Matters Statistically

This trial raises a statistical challenge that is relevant to studies of symptoms that can overlap across conditions. The study summary describes overlap between depressive symptoms and hemodialysis-related complications, including fatigue, appetite change, sleep difficulty, nausea, and cramps. In such settings, how an outcome is defined can influence what the measurement represents. The registry identifies PHQ-9 remission as the primary question, but does not report the primary outcome result or clarify whether the analysis treated remission as a threshold outcome, a continuous score, or both.

The design also makes the distinction between description and causal inference especially important. A single-group study can report what happened among its participants, but the absence of a randomized comparator prevents a direct treatment-versus-control contrast. Recognizing that limitation is essential when interpreting an intervention study, particularly when the record reports no inferential analysis.

Enrollment is another practical consideration. The study summary describes approximately 96 participants for the intervention phase, whereas the registry lists 16 enrolled. The record does not explain this difference or report a sample-size rationale. Without a primary outcome estimate and its uncertainty, readers cannot assess how much precision the final enrollment supported.

Finally, the registry record illustrates why endpoint definitions, analysis plans, and outcome reporting need to align. A remission threshold is readily interpretable as a participant-level classification, while a mean and standard deviation describe the score distribution differently. Clear reporting of the chosen analysis, missing-data approach, and uncertainty would help readers assess what the results can support. Those details are not reported in the registry record.

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 primary limitation for interpreting this trial is that the registry record does not report the primary endpoint result. No week 12 PHQ-9 summary, remission count, treatment-effect estimate, or uncertainty interval is listed. The statistical analysis is also not reported, so the intended comparison or summary cannot be reconstructed from the record.

The study is single-group, with allocation listed as not applicable and masking listed as none. It therefore lacks a randomized control group for estimating a comparative effect. The record does not describe how outcome assessment was conducted or how potential influences apart from the intervention were considered.

The endpoint has an unresolved reporting distinction: it defines remission using a week 12 score below 5, but also describes the outcome as a continuous measure summarized by a mean and standard deviation. The reported timeframe is 3 years. How that timeframe relates to the week 12 endpoint is not explained in the registry record.

The registry lists enrollment of 16, while the study summary describes approximately 96 patients planned for the Phase II intervention group. The record does not explain this difference or give the sample-size justification. It also does not report the number assessed at week 12, missing-data handling, analysis populations, adherence information, interim analyses, or a detailed statistical plan.

The safety record gives counts but little detail about the other adverse event. No serious adverse-event terms are listed, and the record does not provide descriptions or timing for that event. These limitations restrict both outcome and safety interpretation to the limited information recorded.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Identifying and Treating Depression in Hemodialysis Patients — NCT03390933.
• Registry record last updated 2024-10-17; status last verified 2024-10.
• Results first posted 2024-10-17.
• 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

NCT03390933 is a completed, single-group Phase 4 study sponsored by MetroHealth Medical Center. The registered intervention is fluoxetine, described in the study summary as weekly treatment under direct observation. The registry lists enrollment of 16, no masking, and allocation as not applicable.

The primary question concerns depression remission among hemodialysis patients, defined as a week 12 PHQ-9 total score below 5. The outcome is also characterized as a continuous measure summarized by a mean and standard deviation; the record does not clarify the intended primary analysis. It reports 0 serious adverse events among 16 at risk, 1 other adverse event among 16 at risk, and 0 deaths.

The registry record does not report a primary outcome estimate, statistical test, confidence interval, missing-data method, or detailed analysis plan. It therefore describes the design, endpoint definition, enrollment, and safety counts, but does not establish the observed remission outcome or its precision.