Health and Wellbeing of Pregnant and Post-Partum Women During the COVID-19 Pandemic: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Health and Wellbeing of Pregnant and Post-Partum Women During the COVID-19 Pandemic (NCT04385238), a registered phase not stated study. The primary outcome is Number of Participants With Symptoms of Post-traumatic Stress Disorder.

2. Clinical Question

3. Trial Design

This completed study is described as an online survey of pregnant and recently postpartum women during the COVID-19 pandemic. The sponsor is Pregistry. The study start date is 2020-05-15, and the primary completion date is 2020-06-20. Enrollment is listed as 6894. The registry’s status is COMPLETED; that status does not by itself indicate that every enrolled person completed the survey or contributed to every outcome.

The record identifies two populations: pregnant women aged 18 years or older, and postpartum women aged 18 years or older who gave birth within the last 6 months. It lists no intervention beyond the online survey itself. The record does not state a randomization procedure, and the two groups are not a like-for-like control comparison. Their membership reflects pregnancy or postpartum status, rather than assignment to competing interventions.

The study’s stated purpose is to assess health and wellbeing during the pandemic. The primary outcome is a count of participants with PTSD symptoms, with a timeframe covering pregnancy or the period within 6 months after giving birth. The survey questions assess symptoms during the past 7 days. This difference between the broader outcome timeframe and the symptom-recall period is relevant when interpreting what the measure captures.

The registry lists two outcome measures and zero analyses. It does not report group-specific enrollment, response rates, the number of participants with the primary outcome, or a statistical analysis plan. Details of recruitment, survey completion, and handling of incomplete responses are not reported in the registry record. The population descriptions therefore define who the groups were intended to represent, but do not establish how representative respondents were of those populations.

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.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Symptoms of Post-traumatic Stress Disorder, measured over Anytime during pregnancy or within 6 months after given birth..

The primary endpoint is the number of participants with symptoms of post-traumatic stress disorder. The registry says symptoms are assessed with the Impact of Events Scale-6, a six-item measure that includes two items from each of three subscales: intrusion, hyperarousal, and avoidance. Participants report symptoms experienced in the past 7 days using a Likert scale from 0 (not at all) to 4 (extremely). The outcome timeframe is described as any time during pregnancy or within 6 months after giving birth.

In general, a symptom measure can make a broad psychological construct easier to assess consistently across survey respondents. A participant count can also be straightforward to communicate, provided the rule used to classify someone as having the outcome is clear. The registry record does not report the scoring rule, threshold, or other classification criteria used to convert item responses into the participant count. It also does not report the observed count or the denominator used for that outcome.

Thus, the endpoint description identifies the intended construct and instrument, but does not fully specify how responses became a binary outcome. The posted information does not allow the reader to independently reproduce the classification or evaluate the observed frequency. The second listed outcome measure is not described in the available record details.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a binary primary outcome in terms of participants with an event: participants classified as having PTSD symptoms. The listed parameter is a count of participants. A count alone does not express how common an outcome was unless its denominator is also known. The registry record does not report the observed count, the group-specific denominators, or the classification threshold. It therefore does not support a reproducible estimate of symptom frequency from the posted outcome details.

What a count and a proportion represent

In general, a count records how many observations meet a definition. A proportion relates that count to the number of people assessed under the same definition. Those quantities answer different questions: the count describes the number of observed cases in a dataset, while the proportion describes their share of the relevant population in that dataset. Interpreting either requires knowing who was assessed, who had usable data, and what qualified as an outcome. For this study, the record supplies the enrollment total but not the primary-outcome count or its denominator. Enrollment cannot be substituted for the number assessed on the endpoint.

How the instrument relates to the endpoint

The Impact of Events Scale-6 is described as six items covering intrusion, hyperarousal, and avoidance. Each item response is on a Likert scale from 0 (not at all) to 4 (extremely), with symptoms reported for the past 7 days. In general, item-level responses can be combined or classified according to a scoring rule. Different rules can yield different definitions of a positive outcome, so the scoring and threshold need to be stated to interpret a participant count. The registry does not report the rule used. It also does not explain how a recent symptom recall period corresponds to the broader pregnancy or postpartum timeframe attached to the outcome.

What an estimate of uncertainty would add

In general, a confidence interval describes a range of values compatible with an estimate under a specified statistical procedure. It helps communicate precision; it does not remove bias from participant selection, measurement, or missing responses. No confidence interval or other uncertainty estimate is reported for this primary endpoint. A p-value would address compatibility with a specified statistical hypothesis under a model, but it would not describe the size or importance of an outcome on its own. No p-value or hypothesis test is reported either.

The record does not report a statistical model, adjustment variables, or a planned inferential comparison. It would therefore be inappropriate to describe a particular regression, variance estimator, or comparison procedure as the study’s method. The group labels alone do not establish a comparison analysis. They identify the populations, but the registry does not say that group differences were tested.

Why the planning assumptions are not study results

The planning illustration uses a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It is described as based on a stated fraction of an observed effect, with participant counts expressed per arm for the non-time-to-event calculations. Those assumptions concern a planning exercise, not the observed survey sample, and equal allocation in an illustration does not show that the study enrolled equal numbers in its population groups. The record does not describe those assumptions as the trial’s original design plan. Planning sample sizes are not observed power, and they do not replace a reported outcome estimate or its uncertainty.

In general, a planning calculation asks how much information might be needed under assumptions about an effect, allocation, and statistical procedure. Its output depends on those choices. It does not establish that the effect occurred, nor does it show that the study was capable of detecting an effect after data collection. The registry record does not report a sample-size justification for the survey itself.

Why a simple comparison would need caution

In general, a comparison between groups can be distorted when group membership is associated with characteristics that also relate to the outcome. Random allocation can help balance such characteristics in treatment comparisons, but this record does not report randomized allocation and the groups are defined by pregnancy status. A difference between these populations would therefore be descriptive unless a suitable design and analysis supported stronger interpretation. The registry does not report an adjusted analysis or information sufficient to assess confounding.

For count or proportion data, the analytic denominator and the way missing observations are handled are important. In general, missing responses can alter both the numerator and denominator, and a complete-case estimate can differ from an estimate using a method that accounts for missingness. The registry does not state whether responses were complete, how incomplete questionnaires were handled, or which analysis population was used. Accordingly, no specific statistical method can be attributed to the posted primary result.

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("Pregnant Women", "Post-partum Women")
n      <- c(5712, 1182)
events <- c(1028, 532)
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  Pregnant Women  5712  1028  18.0  17.0  19.0  17.0  19.0  17.0  19.0
ARM  Post-partum Women  1182  532  45.0  42.1  47.9  42.2  47.9  42.2  47.9

11. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and zero analyses. It does not report a multiplicity strategy, such as a hierarchy of outcomes, an adjustment for multiple testing, or a distinction between confirmatory and exploratory analyses. Without posted tests or a stated analysis plan, it is not possible to determine whether multiplicity was addressed or whether any reported inference was intended to be confirmatory. The record does not report a family of hypotheses or testing procedure.

Missing-data handling is also not reported. The enrollment total is 6894, but the record does not give the number completing the survey, the number with complete Impact of Events Scale-6 responses, or the denominator used for the primary outcome. It does not say whether partially completed surveys were included, excluded, or handled through an imputation or other method. These omissions prevent assessment of how missing answers might affect an outcome estimate.

In general, a missing-data method makes assumptions about why information is absent and how the observed data relate to the missing values. Those assumptions can affect conclusions, so the method and analysis population should be described. No such assumptions or methods are reported in the registry record. The population included in an analysis is also not specified: there is no account of eligibility exclusions, survey nonresponse, or participant-level outcome availability.

The record does not report sensitivity analyses for missing data or multiplicity. This is a reporting limitation, not evidence that such procedures were or were not conducted outside the registry. The posted information supports neither a claim that all enrolled participants were analyzed nor a claim that the stated enrollment is the endpoint denominator. With no outcome analyses listed, the effects of missingness and multiple testing on statistical inference cannot be evaluated.

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

The registry record supports a limited but clear description of the study’s purpose, population categories, survey approach, and intended primary measure. It describes an online assessment of health and wellbeing during the COVID-19 pandemic and identifies PTSD symptoms as the primary endpoint. It does not report the primary-outcome count, a proportion, a group contrast, or a precision estimate. Therefore, the posted information does not establish how frequently participants reported symptoms, whether the two groups differed, or how uncertain any estimate would be.

The record’s enrollment figure is not a result for the PTSD endpoint. It does not indicate how many participants completed the relevant items, how many responses were usable, or how many met an outcome threshold. Likewise, the completed status does not confirm that every enrolled participant contributed complete data. The zero entries in adverse-event fields are not a substitute for symptom results or a description of mental health experiences.

In general, a survey can describe answers from people who respond, but extending those findings to a wider population depends on how respondents were recruited and how participation relates to the outcomes. The registry does not report enough recruitment or response information to assess representativeness. This does not show that the sample was unrepresentative; it means that representativeness cannot be evaluated from the posted details.

The measure asks about symptoms in the past 7 days, while the outcome timeframe refers to pregnancy or the period within 6 months after giving birth. These descriptions should not be treated as equivalent without the scoring and timing rules. The record does not explain how an item response was converted into a participant-level classification.

Accordingly, the result should be understood as an outcome that the study intended to assess, not as a reported finding about symptom prevalence or a causal effect. The record does not describe an assigned intervention or a randomized comparison. It cannot support conclusions about whether a treatment changes symptoms. More broadly, absence of reported analysis is not evidence of no association, no symptoms, or no uncertainty.

13. Why This Trial Matters Statistically

This record illustrates why a detailed outcome definition and a reported analysis are both needed to interpret clinical research. The endpoint is named, the instrument is identified, and the item domains and response scale are described. Yet the registry does not state the rule that converts responses into a count of participants with symptoms. Without that rule, readers cannot reproduce the endpoint classification or know precisely what a positive outcome represents.

It also illustrates the distinction between enrollment and the analytic sample. Enrollment is listed as 6894, but the number with complete primary-outcome data and the outcome denominator are not reported. That distinction is important for any survey estimate: a total enrollment figure alone does not tell readers how much information supported a particular result.

The two populations are clinically and contextually distinct, but they are not described as randomized treatment arms. Statistical comparisons between them, if made, would need interpretation as comparisons of groups whose membership is based on pregnancy status, not as effects of assigned care. The record does not report whether any such analysis was conducted. Explicitly recognizing the design prevents a descriptive contrast from being mistaken for a causal treatment effect.

Finally, precision and missingness are central to assessing a result. No endpoint estimate or uncertainty measure is posted, and missing-data procedures are not described. These are not cosmetic details: they determine what can be inferred from responses and how broadly the estimate might apply. The study’s stated focus on health and wellbeing during the pandemic makes transparent reporting especially useful, while the registry information alone remains insufficient to quantify its primary finding.

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 direct limitation for interpreting this study is that the registry record does not report the primary outcome result. Although the measure and its timeframe are described, the number of participants meeting the symptom definition, the denominator, and any estimate of uncertainty are absent. The registry lists zero analyses, so no statistical comparison or inferential result is available to assess.

The endpoint classification is not fully reproducible from the description. The record identifies the Impact of Events Scale-6 and its six items, but does not report the scoring procedure or threshold used to classify participants as having symptoms. It also pairs a broad timeframe—during pregnancy or within 6 months after giving birth—with a past-7-days symptom recall period, without explaining how these were linked in the analysis.

Enrollment is listed as 6894, but the record does not give the number of respondents in each group, the number with complete outcome data, or response rates. Recruitment procedures, survey nonresponse, and handling of incomplete questionnaires are not reported. As a result, the analytic sample and the potential influence of missing responses cannot be evaluated.

The groups are not a like-for-like control comparison and no randomized allocation is stated. The record does not report adjustment for differences between pregnant and postpartum participants. Any group contrast would therefore require caution and could not be interpreted as a treatment effect on the basis of this record. The registry also does not report a sample-size justification for the study itself, a prespecified analysis plan, or a multiplicity approach.

These are limits of the information recorded; they do not prove that additional analyses or procedures were not undertaken elsewhere. They do, however, define what can be concluded from the registry record: the study’s stated survey purpose and outcome can be described, but its primary finding and statistical precision cannot be evaluated.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Health and Wellbeing of Pregnant and Post-Partum Women During the COVID-19 Pandemic — NCT04385238.
• Registry record last updated 2021-01-07; status last verified 2021-01.
• Results first posted 2021-01-07.
• 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.

18. Record Summary

NCT04385238 is a completed online survey sponsored by Pregistry, with enrollment listed as 6894. The study began on 2020-05-15 and reached primary completion on 2020-06-20. Its stated purpose was to assess health and wellbeing during the COVID-19 pandemic among pregnant and recently postpartum women.

The registry describes pregnant women aged 18 years or older and postpartum women aged 18 years or older who gave birth within the last 6 months. There was no intervention beyond the survey. The primary outcome is the number of participants with PTSD symptoms, assessed using the Impact of Events Scale-6, with a stated period during pregnancy or within 6 months after giving birth and questions about symptoms in the past 7 days.

The registry lists two outcome measures and zero analyses. It does not report the primary outcome count, its denominator, a group comparison, or an uncertainty estimate. The symptom classification rule, missing-data handling, analysis populations, and multiplicity procedures are not reported in the registry record.