This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Depression, Epinephrine, and Platelet Function (NCT00166114), a randomized phase 4 study. The primary outcome is Response of Participants, Defined by Change in the 21-item Hamilton Depression Rating Scale (HDRS) From Baseline to Week8.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00166114 |
| Phase | Phase 4 |
| Condition | Major Depressive Disorder |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 40 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Emory University |
| Results posted | Yes |
2. Clinical Question
Population
Men and women described as having experienced sexual and/or physical abuse before age 12, in a study concerning major depressive disorder.
Intervention
Escitalopram.
Comparator
Desipramine, the other listed drug intervention. The registry record does not describe a placebo group.
Primary question
How many participants fell into each listed response category on the 21-item Hamilton Depression Rating Scale from baseline to week 8?
The registry’s broader description concerns whether adult survivors of childhood adversity experience heightened negative emotions and physical responses to stress, and whether altered norepinephrine or serotonin systems might be involved. It states the investigators’ expectation that survivors would experience heightened emotional and physical responses to stress. That expectation is not itself a reported result.
The registered primary outcome is narrower than that broad research rationale. It records participants as showing no response, partial response, or response according to change in the Hamilton Depression Rating Scale between baseline and week 8. The registry describes the scale as measuring depression severity, with higher scores indicating greater severity. The outcome therefore concerns recorded symptom-score response categories; it is not a direct measure of stress-related physical responses, brain systems, or platelet function.
The registry lists escitalopram and desipramine as the study interventions, but the outcome counts and a direct statistical comparison between those groups are not reported in the registry record. The posted information therefore establishes the question and measurement framework, but does not establish how the response categories were distributed or whether the groups differed.
3. Trial Design
The registry identifies this as a phase 4, randomized, double-masked, parallel-group study. Escitalopram and desipramine are the listed drug interventions. The record lists an enrollment of 40 and a completed status. It gives a study start of 2002-02 and primary completion of 2009-01. These details describe the registered study, but do not establish how many participants contributed data to the primary outcome.
The population is described in the study summary as men and women who experienced sexual and/or physical abuse before age 12. Major depressive disorder is the listed condition. The registry does not report further eligibility criteria in the primary outcome information, nor does it provide arm descriptions beyond the intervention names. Details such as the drug regimens, duration of treatment, and procedures used to maintain masking are not reported in the registry record.
Randomized allocation means assignment to study groups was described as random. Double masking indicates that the registry characterizes the study as double-masked; which people were masked, and how masking was implemented, are not reported in the registry record. A parallel model indicates that the listed interventions were organized as parallel groups rather than as a crossover comparison. The registry does not describe allocation concealment or the allocation ratio.
The primary outcome timeframe is baseline to week 8. The registry describes the outcome as the number of participants in response categories based on the 21-item Hamilton Depression Rating Scale. Although the record lists one outcome measure and one analysis, it does not report the analysis method, group-specific primary outcome counts, or the estimated comparison. The study design labels alone cannot resolve those omissions or establish the precision of an intervention contrast.
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
| Stage | Escitalopram | Desipramine |
|---|---|---|
| STARTED | 21 | 19 |
| COMPLETED | 7 | 13 |
| NOT COMPLETED | 14 | 6 |
Reasons for not completing this period:
| Reason | Escitalopram | Desipramine |
|---|---|---|
| Protocol Violation | 2 | 1 |
| Withdrawal by Subject | 10 | 4 |
| Adverse Event | 2 | 1 |
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.
| Characteristic | Unit | Escitalopram | Desipramine | Total |
|---|---|---|---|---|
| Participants analysed | 21 | 19 | 40 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 21 | 19 | 40 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 8 | 6 | 14 |
| Sex: Female, Male: Male | Participants | 13 | 13 | 26 |
| Region of Enrollment: United States | participants | 21 | 19 | 40 |
6. Primary Endpoint
The registry lists the primary outcome as Response of Participants, Defined by Change in the 21-item Hamilton Depression Rating Scale (HDRS) From Baseline to Week8, measured over Baseline, Week 8.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants categorized as showing no response, partial response, or response on the 21-item Hamilton Depression Rating Scale (HDRS), comparing baseline with week 8. The registry describes the HDRS as a measure of depression severity. Its score ranges from 0 to 60, with higher scores indicating greater severity. The record describes items with different scoring ranges and says the total score is the sum across all 21 items.
The registry defines no response as < 25% change in the depression rating scale score, partial response as < 50% to >25% change, and response as 50% or greater change. That wording is reproduced in the outcome description; additional detail on how change was calculated, including the precise direction and handling of boundary values, is not reported in the registry record.
A categorical response endpoint can make a symptom-score change easier to interpret as a participant count in each status group. It also reduces information compared with analyzing the underlying score, because participants with different score changes may fall into the same category. The registry does not give the category counts or a group comparison. Consequently, the endpoint definition is available, but the observed response distribution and its statistical precision are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted information establishes the study’s design labels, interventions, outcome definition, and certain adverse-event counts. It does not report the primary outcome counts for escitalopram or desipramine. It also does not report an effect estimate, confidence interval, test statistic, or p-value for the primary outcome. The central comparative result therefore cannot be interpreted from the registry record.
The endpoint is defined as participant counts in response categories based on change in HDRS score from baseline to week 8. A count in each category would describe the observed distribution in the study groups. A statistical comparison would additionally need to state how the groups were contrasted and quantify uncertainty. Neither group-specific response counts nor such a comparison are reported in the registry record. There is therefore no basis in the posted primary outcome information to characterize the difference between interventions as large, small, precise, or statistically distinguishable.
The record’s enrollment of 40 is a registered enrollment figure, not a statement of the number analyzed for the primary endpoint. The number of participants with available baseline and week 8 scores, and the number included in the primary analysis, are not reported in the registry record. Those quantities matter because missing outcome data can change both the observed category distribution and the uncertainty of a comparison.
The registry lists one outcome measure and one analysis, but the primary outcome description contains response categories and a baseline-to-week-8 assessment. The record’s skip note says the primary outcome has several categories or time points and was not reduced to one comparison. Thus, no single contrast should be inferred from the outcome description. No multiplicity adjustment or prespecified primary contrast is reported in the registry record.
Safety counts are separate from the primary efficacy endpoint. The registry lists one serious adverse event among 21 at risk in the escitalopram group and none among 19 at risk in the desipramine group. For other adverse events, the listed counts are 13 among 21 at risk and 18 among 19 at risk, respectively. These are descriptive counts; the registry does not report a statistical comparison or causal assessment for them. Death counts are not reported in the registry record.
Overall, the posted record supports a description of the trial question and the recorded outcome framework, but not a conclusion about comparative primary-outcome results. Absence of a reported result is not evidence that the groups were the same, nor evidence that one intervention produced a better outcome. The primary response data and their analysis are not reported in the registry record.
9. Statistical Methods Explained
Statistical interpretation depends on separating what the design says from what the outcome results show. The registry identifies randomized allocation, double masking, and a parallel model. These labels describe important features of the study design, but they do not substitute for an analysis result. The record does not describe the randomization procedure, how masking was maintained, or the planned statistical model.
What does a participant count represent?
As a general statistical explanation, an event count records how many people in a defined group meet a specified outcome. For a categorical endpoint such as the HDRS response classification, group-specific counts are meaningful only alongside the relevant denominators and the category definitions. The registry gives the categories and describes the endpoint as a count, but the primary category counts are not reported in the registry record. Without them, a response distribution or group contrast cannot be reconstructed.
The registry classifies the outcome as a count of participants with an event while its description distinguishes no response, partial response, and response. Those categories should not be collapsed into one binary result without a stated rule. The record’s skip note explicitly says the primary outcome has several categories or time points and was not reduced to one comparison. A reader should therefore avoid treating a particular pair of categories as the sole primary comparison.
Why does uncertainty matter?
As a general statistical explanation, an estimate summarizes an observed difference or distribution, while a confidence interval describes the range of values reasonably compatible with the data under the analysis assumptions. A narrow interval indicates greater precision than a wide interval; an interval that includes values representing no difference may leave substantial uncertainty about the direction or size of a contrast. These interpretations require an estimate and interval. Neither is reported for the primary outcome in the registry record.
A p-value, when reported, addresses how compatible the observed data are with a specified statistical model and null hypothesis. It does not measure the size or importance of an effect, and it does not by itself establish a causal explanation. No primary-outcome p-value or test is reported in the registry record, so statistical significance cannot be assessed from the posted primary outcome information.
What does randomization contribute?
As a general explanation, random assignment can help balance measured and unmeasured characteristics between groups on average, supporting a causal comparison when the study is conducted and analyzed appropriately. Randomization does not guarantee exact balance in a particular trial. It also does not address missing outcome measurements automatically. The registry’s randomized label is relevant, but details of the allocation process, analysis population, and handling of missing data are not reported in the registry record.
Double masking can reduce some risks of biased behavior or assessment when masking is successfully maintained. The registry gives the design label but does not say who was masked or how masking was assessed. The HDRS involves a rating of symptoms; the record does not specify who performed the ratings or whether the assessors were among those masked. Those details should not be inferred from the label alone.
How should the response thresholds be read?
The endpoint description uses percentage-change thresholds to assign response categories. The stated rules are no response at < 25% change, partial response at < 50% to >25% change, and response at 50% or greater change. The registry does not provide the calculation details that would clarify the boundaries and direction of change. The scale’s higher scores indicate greater severity, but the record does not give a more complete operational definition of the percentage change. Readers should retain the registry’s stated wording rather than silently reinterpret it.
Converting a continuous score to categories can aid communication, but it discards distinctions among score changes within the same category and can make results sensitive to the chosen thresholds. This is a general property of categorization, not a finding about this trial. The record does not report a continuous-score analysis alongside the categorical outcome.
What can planning calculations establish?
The registry describes a sample-size planning illustration based on a fraction of the observed effect, a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation. It also states that the illustrations are not the trial’s own design and are not observed power. These are planning assumptions, not evidence that the trial had a particular power or that a primary result was statistically persuasive. The actual planning outputs and the observed primary effect are not reported in the registry record. In particular, an observed effect cannot be evaluated from the primary outcome counts because those counts are absent.
As a general explanation, a planning calculation asks how much information a future study might need to detect an assumed effect under chosen assumptions. It is not a substitute for analyzing observed data. Calculations based on an observed effect are especially dependent on how that effect was estimated. None of those planning concepts fills the gap left by absent primary outcome results.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one outcome measure and one analysis, but the primary outcome description includes multiple response categories and specifies assessment from baseline to week 8. The registry’s skip note says the outcome has several categories or time points and was not reduced to one comparison. A prespecified contrast among categories, or a stated approach to testing multiple contrasts, is not reported in the registry record.
Multiplicity arises when several outcomes, time points, subgroups, or comparisons are tested. As a general statistical matter, conducting multiple tests can increase the chance of at least one apparently notable result unless the analysis plan accounts for that. Whether an adjustment is appropriate depends on the planned questions and testing framework. The registry does not report a multiplicity strategy, so no adjustment or hierarchy should be assumed.
The record does not report the number with observed HDRS data at baseline and week 8, reasons for missing measurements, or how missing outcomes were handled. It also does not state whether the primary analysis used an intention-to-treat population, a per-protocol population, or another analysis set. Enrollment of 40 does not establish the analysis denominator. Without these details, the completeness of the primary outcome data and the impact of missingness cannot be assessed.
As a general explanation, missingness can affect estimates when the availability of an outcome is related to participant characteristics or outcomes. Different handling strategies rely on different assumptions; those assumptions should be described rather than inferred. The registry record does not give a missing-data method, sensitivity analysis, or analysis-population definition. The reported category counts and their denominators are also not available, preventing assessment of how much information contributed to the primary comparison.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Escitalopram | 1 | 21 | 4.8% |
| Desipramine | 0 | 19 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Escitalopram | 13 of 21 |
| Desipramine | 18 of 19 |
Most frequent serious adverse event terms
| Event term | Organ system | Escitalopram | Desipramine |
|---|---|---|---|
| Suicide gesture (superficial lacerations to wrists with a razor) | Psychiatric disorders | 1 of 21 | 0 of 19 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Escitalopram | Desipramine |
|---|---|---|---|
| Headache | Nervous system disorders | 3 of 21 | 3 of 19 |
| Dry Mouth | Skin and subcutaneous tissue disorders | 2 of 21 | 2 of 19 |
| Constipation | Gastrointestinal disorders | 0 of 21 | 2 of 19 |
| Indigestion | Gastrointestinal disorders | 1 of 21 | 1 of 19 |
| Upper Respiratory Infection | Infections and infestations | 1 of 21 | 1 of 19 |
| Fatigue | Nervous system disorders | 2 of 21 | 0 of 19 |
| Orthostatic Tachycardia | Cardiac disorders | 0 of 21 | 1 of 19 |
| Rash | Skin and subcutaneous tissue disorders | 0 of 21 | 1 of 19 |
| Pruritis | Skin and subcutaneous tissue disorders | 0 of 21 | 1 of 19 |
| Heartburn | Gastrointestinal disorders | 1 of 21 | 0 of 19 |
Serious events with the highest arm-level rate: suicide gesture (superficial lacerations to wrists with a razor) (4.8%).
The registry lists serious adverse events separately for the two intervention groups. For escitalopram, 1 participant with a serious adverse event is listed among 21 at risk. For desipramine, 0 participants with a serious adverse event are listed among 19 at risk. The registry also lists other adverse events for 13 of 21 at risk in the escitalopram group and 18 of 19 at risk in the desipramine group. These are recorded counts, not estimates of treatment effects.
The registry identifies “Suicide gesture (superficial lacerations to wrists with a razor)” as a top serious adverse-event term and lists 4.8%. The record does not link that term to a particular group in the provided adverse-event information, so it should not be attributed to either intervention based on these entries alone. Death counts are not reported in the registry record; a missing death count should not be interpreted as a confirmed absence of deaths.
As a general statistical point, adverse-event counts describe events recorded under the registry’s reporting conventions. They do not by themselves establish that an intervention caused an event, and small counts can leave considerable uncertainty about comparative risk. The registry does not report a formal safety comparison, event timing, severity details beyond the listed term, or an assessment of causality. The counts should therefore be read descriptively and kept distinct from the unreported primary HDRS outcome.
12. What the Result Does, and Does Not, Mean
The registry record describes a randomized comparison of escitalopram and desipramine in a study concerning men and women with childhood abuse and major depressive disorder. It specifies a primary outcome based on HDRS response categories from baseline to week 8. The posted record does not include the response counts for either group or a statistical comparison. It therefore does not establish whether the groups differed on the registered primary outcome.
This absence should not be interpreted as evidence of no difference, and it should not be taken as evidence that either intervention was superior. A comparative conclusion would require observed outcome data, an analysis definition, and an account of uncertainty. Those primary outcome results are not reported in the registry record.
The trial’s broad rationale concerns emotional and physical responses to stress and possible norepinephrine or serotonin system changes among adult survivors of childhood adversity. The registered HDRS endpoint addresses depression severity through score-based response categories; it does not directly test all of those broader biological or stress-response questions. The posted outcome definition should not be stretched into claims about platelet function, brain mechanisms, or medical illness.
The adverse-event figures provide descriptive information on recorded serious and other adverse events among those listed as at risk. They do not supply a formal comparative safety estimate or establish causation. The reported serious-event term and percentage do not identify a group in the posted details. Death counts and further safety-analysis methods are not reported in the registry record.
The record’s completed status and enrollment figure document the registered study’s status and enrollment, but do not reveal the number contributing to each outcome analysis. Without denominators and outcome results for the primary endpoint, neither magnitude nor precision of a comparative effect can be judged. The defensible reading is limited to the design description, measurement definition, and adverse-event counts that the registry records.
13. Why This Trial Matters Statistically
This trial illustrates why a registered endpoint definition and an observed endpoint result are different kinds of information. The registry explains how HDRS scores were intended to map to response categories and gives the assessment timeframe. But without category counts, denominators, and a stated comparison, readers cannot estimate the observed response distribution or its uncertainty.
The outcome also highlights the statistical consequences of categorization. The HDRS is described as a severity scale with a total score, while the primary endpoint reports participant counts in threshold-based groups. Categorization may make a result easier to communicate, but it can conceal variation among participants assigned the same category. The registry does not report a complementary analysis of score changes, so the relationship between the category result and the underlying score distribution cannot be assessed.
The record also distinguishes trial design labels from details needed to judge analysis quality. Randomization, masking, and a parallel model are useful design information, but the registry does not describe the analysis population, missing-data handling, or statistical test. Those omissions matter for understanding the strength and limits of a reported comparison. Here, the primary comparison itself is not reported in the registry record.
Finally, the adverse-event counts underscore the need to separate descriptive safety reporting from causal or comparative conclusions. Counts and denominators can inform a descriptive reading, but they do not by themselves quantify uncertainty or establish attribution. This study is statistically informative as an example of how much interpretation depends on reporting the outcome data and analysis details alongside the protocol-level description.
14. 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 consequential limitation of the posted record is that it does not report the primary outcome counts. The registry gives the endpoint definition and timeframe, but not the response distribution by intervention group, the analysis denominator, an effect estimate, or its uncertainty. Comparative efficacy therefore cannot be assessed from the record.
The response threshold wording is not fully operationalized in the outcome description. It specifies percentage-change boundaries but does not explain the exact calculation or clarify the direction of change and boundary handling. The HDRS scoring description identifies higher scores as greater severity, but the registry does not provide additional details needed to reproduce the response classification independently.
Important design and analysis details are also absent. The record does not report drug regimens, treatment duration, the allocation ratio, the randomization procedure, who was masked, or the primary statistical method. It does not define the analysis population or explain missing outcome handling. These omissions limit assessment of bias, completeness, and precision.
The study summary gives a broad biological and stress-response rationale, while the registered primary endpoint is HDRS response categorization. The outcome data needed to evaluate even that narrower question are not reported in the registry record, and the endpoint is not a direct measure of every mechanism described in the rationale. Safety information is also limited to listed counts and a serious-event term; timing, causality assessment, and a formal group comparison are not reported. Death counts are not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Depression, Epinephrine, and Platelet Function — NCT00166114.
- Registry record last updated 2015-07-23; status last verified 2015-07.
- Results first posted 2015-07-23.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry identifies NCT00166114, “Depression, Epinephrine, and Platelet Function,” as a completed phase 4 randomized, double-masked, parallel-group study sponsored by Emory University. It lists an enrollment of 40, a start of 2002-02, and a primary completion of 2009-01. Escitalopram and desipramine are the listed interventions, and major depressive disorder is the listed condition.
The primary outcome is the number of participants classified by change in the 21-item HDRS from baseline to week 8. The registry defines no response, partial response, and response using percentage-change thresholds, but primary category counts and the statistical comparison are not reported in the registry record. Serious and other adverse-event counts are listed by intervention group; deaths are not reported. The record does not describe the primary analysis method, analysis population, missing-data handling, or multiplicity approach.