ASIAN HF Registry, A Prospective Observational Study: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for ASIAN HF Registry, A Prospective Observational Study (NCT01633398), a registered phase not stated study. The primary outcome is All Cause and Cause-specific Death.

2. Clinical Question

The broad aims described in the record include assessing the burden of mortality and sudden cardiac death, identifying risk factors, examining sociocultural barriers to preventive device therapy, and studying genetic variants associated with HFrEF versus HFpEF. These are aims, not reported findings. The posted primary outcome is a count of participants with deaths; it does not provide adjusted effect estimates, uncertainty intervals, or a causal comparison between heart-failure categories.

3. Trial Design

The ASIAN HF Registry is described as a prospective, multinational Asian observational study of patients with symptomatic stage C heart failure. It includes HFrEF and HFpEF, and has a broad focus on mortality, sudden cardiac death, risk factors, barriers to preventive device therapy, and genetic variants. The record lists saliva genetic testing, but does not describe an assigned treatment or randomized allocation. The allocation method is not stated.

The registry reports enrollment of 6329 and a completed status. Its listed start is 2012-09, and primary completion is 2020-03-06. These record dates describe the registry, not the timing of an individual participant’s follow-up or the period over which each death was counted.

The primary endpoint is titled “All Cause and Cause-specific Death” and is measured as participants. Its timeframe is listed as 2 years follow up. However, the population description says that patients with outcomes available at 1 year were examined for all-cause and cardiovascular death, with patients lost to follow-up excluded. How the 1-year description relates to the 2-year timeframe is not reported in the registry record.

The posted results separate HFrEF and HFpEF. This grouping allows the recorded death counts to be read by heart-failure category, but it does not establish that the groups are comparable with respect to other characteristics. The record does not report the countries, recruitment sites, eligibility details, methods for defining or confirming deaths, or participant characteristics needed to assess those comparisons.

The record lists two outcome measures and no analyses. It does not report a statistical analysis plan, model specifications, covariate adjustment, or a rationale for enrollment size. These omissions limit the interpretation of the reported counts as estimates of a broader mortality burden or as evidence about risk factors.

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

Analysis population for the primary outcome, as defined in the registry: Patients with outcomes available at 1 year were examined for all-cause and cardiovascular (CV) death. Patients who were lost to follow-up were excluded from the analysis.

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 All Cause and Cause-specific Death, measured over 2 years follow up.

The primary endpoint concerns all-cause and cause-specific death among patients with heart failure. The outcome unit is participants, and the endpoint description identifies the incidence of deaths as the quantity of interest. A death count is a direct way to describe how many participants in a defined population experienced the event during the specified observation period.

All-cause death captures deaths regardless of assigned cause. Cause-specific death separates deaths according to their classification, which can help characterize the types of mortality under study. The population description specifically says that all-cause and cardiovascular death were examined. The record does not report how causes of death were adjudicated, how uncertain causes were handled, or whether cardiovascular death was the only cause-specific category analyzed.

Endpoint timing matters. The timeframe field says 2 years follow up, while the analysis-population description refers to outcomes available at 1 year. The record does not explain whether the latter describes an interim observation, a data-availability rule, or the actual analysis period. Without that clarification, the counts should be interpreted as posted participant counts rather than as fully specified two-year incidence estimates.

Counts are useful for describing recorded events, but by themselves they do not express the precision of an estimated risk or account for differences between groups in follow-up duration. The registry record does not provide confidence intervals, time-to-event estimates, or adjusted comparisons for the primary endpoint. Accordingly, the endpoint supports a descriptive reading of the posted deaths, not a conclusion that one heart-failure category caused more deaths than another.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a participant count represent?

For a binary outcome such as whether a participant experienced death, the event count describes participants recorded with that outcome. The registry reports this kind of count for HFrEF and HFpEF. An event count is not itself a rate unless its denominator and observation period are clearly defined. Here, at-risk figures are reported, but the relationship between the stated 2 years follow up and the population description referring to 1 year is not explained in the registry record.

In general, a rate or risk estimate needs a clearly defined population at risk and a consistent period of observation. In studies with differing follow-up durations, time-to-event methods can account for the amount of time each participant is observed, provided the relevant data and methods are available. The registry record does not report time-to-event estimates or details sufficient to determine whether follow-up duration varied across participants.

Why does observational grouping matter?

In a randomized comparison, allocation can help balance measured and unmeasured characteristics across groups. This registry is observational, and allocation is not stated. HFrEF and HFpEF are clinical groupings, not assigned interventions. General statistical interpretation therefore distinguishes an observed association between category and outcome from a causal effect. The posted counts can describe outcomes within the recorded groups, but cannot show that heart-failure category caused any difference.

Adjustment in a statistical model can account for measured differences in participant characteristics, if the variables are recorded and the model is appropriate. Adjustment does not automatically remove bias: unmeasured factors, measurement error, and model assumptions can still affect results. The registry record reports no analyses, model specifications, covariates, adjusted estimates, or uncertainty intervals. No adjusted conclusion can therefore be drawn from the posted outcome counts.

What does uncertainty add?

In general, a confidence interval describes a range of values reasonably compatible with the data under a statistical model and its assumptions. It communicates estimation uncertainty, which a point estimate or count alone does not. The posted record does not report confidence intervals for the death outcome. It is therefore not possible to assess the precision of a mortality estimate from the registry record alone.

In general, a p-value evaluates how compatible observed data are with a specified null hypothesis under a statistical model. It does not measure the size or clinical importance of an effect, and it does not establish causation. No p-value or statistical comparison for the death counts is reported in the registry record.

How should planning calculations be understood?

General sample-size calculations estimate the information a future study might need under stated assumptions about the effect to detect, allocation, significance level, and statistical model. The record describes a planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. It also says that the effect to detect is a stated fraction of the observed effect. Those are planning assumptions, not evidence about the original registry’s design or its ability to detect an effect.

The record does not report the registry’s own sample-size justification or design assumptions. Any planning illustration based on an observed effect is hypothetical and should not be read as observed power or as a retrospective test of whether the registry “had enough” participants. The posted record gives no analysis results from which to judge the performance of such an illustration, and no calculated planning values are included in the record summarized in the registry.

What can be inferred from the endpoint definition?

The primary endpoint is a count of participants with all-cause and cause-specific death. Such a count is straightforward to interpret only when the outcome definition, ascertainment, follow-up interval, and analysis population are sufficiently clear. The record indicates that lost-to-follow-up patients were excluded and that patients with outcomes available at 1 year were examined, but does not give the exclusion count or explain the timing difference with the 2 years follow up field. Those details affect how a count should be generalized beyond the participants with available outcomes.

The record names Sudden Cardiac Death as a secondary outcome but provides no result for it. A secondary outcome can be statistically informative, but its interpretation depends on how it was defined, how many outcomes were assessed, and whether the analysis plan accounted for multiple testing. Those methods are not reported in the registry record. No conclusion about sudden cardiac death or multiplicity-adjusted evidence can be drawn from its listing alone.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and identifies Sudden Cardiac Death as a secondary outcome. It does not report a multiplicity strategy, such as a prespecified hierarchy or adjustment for testing several outcomes. Without that information, any statistical significance claims across multiple outcomes would need careful interpretation; in this record, no analysis results or p-values are reported.

The primary outcome description says that patients with outcomes available at 1 year were examined for all-cause and cardiovascular death, and that patients lost to follow-up were excluded. The number lost, reasons for loss, and amount of missing outcome information are not reported in the registry record. The record also does not explain how the 1-year outcome-availability statement relates to the listed 2 years follow up timeframe.

Missingness can affect interpretation if participants without recorded outcomes differ from those with available outcomes. In general, excluding participants with missing outcomes may bias an estimate when missingness is related to prognosis or outcome status. This is a general methodological concern, not a finding that bias occurred in this registry. The record does not report sensitivity analyses or methods for handling missing data.

The analysis population is described only as patients with outcomes available at 1 year, with those lost to follow-up excluded. The record does not report a detailed analysis population, participant flow, or the number contributing to each endpoint. It also reports no statistical analyses. These gaps limit assessment of outcome completeness and the relationship between enrollment and the posted death counts.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: death (10.6%).

The registry’s serious-adverse-event listing names Death as a top serious term and reports 10.6%. The record also reports death counts by heart-failure category: 500 in HFrEF and 60 in HFpEF. The denominator and precise context for the 10.6% figure are not reported in the registry record, so it should not be interpreted as a group-specific rate or compared directly with the category counts.

This is an observational registry, not a randomized treatment-safety comparison. The record does not describe an assigned treatment group, a control group, or an attribution process linking deaths to an intervention. The listed saliva genetic testing does not establish that the deaths were caused by testing. The record does not report whether adverse events were attributed to any intervention or how serious events were collected.

Death is also the primary outcome of interest, rather than an adverse event that can automatically be attributed to treatment. The serious-event listing and primary endpoint may reflect related outcome information, but the record does not explain their relationship or whether they use the same population and follow-up period. The 10.6% figure should therefore be read as a registry-listed serious-term summary, not as evidence of treatment-related harm or safety.

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

The posted record documents death counts in both HFrEF and HFpEF groups and gives the corresponding at-risk figures. It describes a prospective observational registry focused on mortality and other questions in Asian patients with symptomatic heart failure. These registry entries are useful for understanding what the registry set out to study and what outcome information it recorded.

The counts do not show that one heart-failure category causes higher mortality than another. The groups were not randomized, and the registry record reports no adjusted analysis, statistical test, or confidence interval. Differences between the groups may reflect characteristics or circumstances not addressed in the posted results. The record does not report the information needed to separate those possibilities.

The counts also do not resolve the stated follow-up period. The endpoint timeframe is 2 years follow up, while the population description refers to outcomes available at 1 year. The record does not explain the relationship, or report how many participants were lost to follow-up and excluded. Consequently, the figures should not be treated as a definitive estimate for a clearly specified period across the full enrolled population.

The registry’s aims concerning sudden cardiac death, risk factors, device-therapy barriers, and genetic variants are not equivalent to reported results. Sudden Cardiac Death is listed as a secondary outcome, but no result for it is reported. No risk-factor, genetic association, or device-barrier estimates are included in the record. The evidence described is therefore limited to the posted descriptive death information, not conclusions about the broader aims.

In general, observational registry findings can describe outcomes in the recorded population and generate questions for further study. They do not alone establish an intervention effect or explain why an outcome occurred. The record’s enrollment figure also should not be taken as the number included in each endpoint analysis, because the analysis population is described in terms of outcome availability and exclusion of lost-to-follow-up patients.

13. Why This Trial Matters Statistically

Statistically, this registry illustrates why the design and the endpoint definition must be read alongside event counts. The record reports deaths in HFrEF and HFpEF, but the categories are observational rather than randomized comparison arms. The counts are therefore descriptive, and a causal interpretation would require assumptions and analyses not reported in the registry record.

The distinction between enrollment and analysis population is also important. The registry reports enrollment of 6329, while the primary outcome population is described as patients with outcomes available at 1 year, excluding those lost to follow-up. The count contributing to each analysis is not reported. Readers should not assume that the enrollment figure is the denominator for the death results.

Follow-up definitions influence the meaning of any outcome estimate. The record lists 2 years follow up but also refers to 1-year outcome availability. Because this is not reconciled, readers cannot tell from the record whether the posted counts correspond to the listed endpoint timeframe. This is not a minor presentation detail: time observed and outcome completeness are part of the definition of a mortality estimate.

The record also demonstrates the difference between research aims and analyzed findings. It names sudden cardiac death, genetic variants, risk factors, and barriers to device therapy as areas of interest, but does not report analyses for them. A listed outcome or scientific objective does not by itself establish that a result was obtained or that an association was demonstrated.

Finally, uncertainty and adjustment matter when comparing groups. Without estimates, confidence intervals, or model details, the magnitude and precision of any group difference cannot be assessed from the posted record. The reported data can orient readers to the registry’s scope and event counts, while the missing analytic details define the limits of what those counts can support.

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 registry record does not reconcile the primary endpoint’s 2 years follow up timeframe with the population description referring to outcomes available at 1 year. The actual observation period represented by the posted counts is therefore unclear. The number of participants lost to follow-up or excluded from the analysis is not reported, nor are reasons for loss or methods for evaluating missing outcomes.

The record reports enrollment of 6329 but does not provide a single total for the primary endpoint analysis. It also does not report participant characteristics, country or site breakdowns, recruitment details, or eligibility criteria beyond the description of symptomatic stage C heart failure and the HFrEF and HFpEF categories. These omissions make it difficult to assess representativeness or evaluate differences between the groups.

Death ascertainment and cause classification methods are not reported in the registry record. Although the endpoint description refers to all-cause and cardiovascular death, the record does not explain adjudication, handling of unknown causes, or whether the same ascertainment methods were used across sites. The secondary outcome listing for Sudden Cardiac Death has no posted result.

No analyses are reported. The registry record does not provide adjusted estimates, uncertainty intervals, statistical tests, model covariates, a multiplicity plan, or sensitivity analyses. It also does not report the registry’s sample-size justification or its own statistical analysis plan. The planning assumptions described in the record should not be mistaken for the original study design.

As an observational registry, it does not provide a randomized treatment comparison. The record does not establish that the HFrEF and HFpEF groups are comparable on factors that may affect mortality. These limitations constrain causal interpretation and any attempt to generalize the counts beyond the participants whose outcomes were available.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: ASIAN HF Registry, A Prospective Observational Study — NCT01633398.
• Registry record last updated 2021-07-14; status last verified 2021-07.
• Results first posted 2021-07-14.
• 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

The record describes the ASIAN HF Registry as a prospective observational study of Asian patients with symptomatic stage C heart failure, including HFrEF and HFpEF. It reports enrollment of 6329, a completed status, a start of 2012-09, and primary completion on 2020-03-06. Saliva genetic testing is listed, but no randomized allocation or treatment comparison is described.

The primary endpoint concerns all-cause and cause-specific death, with a timeframe listed as 2 years follow up. The analysis population description refers to outcomes available at 1 year and excludes patients lost to follow-up. Posted group counts are 500 deaths among 4737 at risk in HFrEF and 60 among 1114 at risk in HFpEF. No analyses are reported. The record does not clarify the follow-up timing discrepancy or provide adjusted comparisons, uncertainty estimates, or a result for the listed secondary outcome of Sudden Cardiac Death.