A Surveillance and Azithromycin Treatment for Newcomers and Travelers Evaluation: The ASANTE Trial: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Surveillance and Azithromycin Treatment for Newcomers and Travelers Evaluation: The ASANTE Trial (NCT01767506), a randomized na study. The primary outcome is The Proportion of Communities With C. Trachomatis Infection Prevalence of 1% or Below.

2. Clinical Question

3. Trial Design

ASANTE was a randomized, parallel-group trial conducted at the community level. The registry record lists 52 communities and 26 communities in each arm. The intervention arm received usual care plus surveillance and azithromycin treatment for newcomer and traveler families; the comparator arm received usual care. The record lists masking as single, but does not report which people or roles were masked.

The registry lists the condition as trachoma and the study status as completed. The recorded start was 2013-01 and primary completion was 2015-12. The phase is listed as NA. The sponsor was Johns Hopkins University. The record does not report the method used to generate the random allocation sequence, how allocation was concealed, or whether communities were stratified before randomization.

Usual care included annual azithromycin MDA under infection and TF thresholds. The intervention added surveillance and treatment directed at newcomer and traveler families. The primary comparison was planned at 24 months and assessed whether communities had reached the specified infection-prevalence threshold. The trial summary also describes plans for follow-up at 30 months: following a Data Safety and Monitoring Committee recommendation in March 2015, 38 of the 52 communities identified as at risk of trachoma re-emergence at 18 months were to be surveyed at 30 months. The record defines at-risk communities at that survey as having infection rates of 1% or less or TF below 5%. This follow-up description is distinct from the primary outcome at 24 months.

The registry does not report a sample-size justification, the intended statistical model in a full protocol, or the identity of the people who carried out outcome assessments. Those details should not be inferred from the fact that the study was randomized or from the analysis label.

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: The trial was conducted at the community level and not at the participant level.Therefore, we are presenting the data only at the community level.

Overall Study

Analysis population for the primary outcome, as defined in the registry: The trial was conducted at the community level

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.

Population: We collected and analyzed data on community level. Age and sex were not part of final analysis.

6. Primary Endpoint

The registry lists the primary outcome as The Proportion of Communities With C. Trachomatis Infection Prevalence of 1% or Below, measured over 24 months.

The primary endpoint is the proportion of communities with C. trachomatis infection prevalence at 1% or below among children ages 1 to 9 years at the 24-month survey. The unit of analysis is the community. In the posted arm results, 7 communities in the intervention arm and 4 in the usual-care arm met the threshold, with 26 communities listed in each arm.

A threshold-based endpoint turns infection prevalence into a community-level classification: each community either met the stated cutoff or did not. The resulting proportion addresses how often communities reached the threshold under each assigned strategy. It does not describe the average infection prevalence across all children, the number of infected children, or each child’s chance of infection. Those are different quantities.

This endpoint fits the trial’s stated policy question about whether communities can stop mass treatment when infection prevalence is sufficiently low. It also supports comparison of the two community-level strategies at a common survey time. However, a threshold discards information about how far a community’s prevalence lies above or below the cutoff. The registry record does not provide community-level prevalence values or details about how the underlying infection measurements were collected. The posted result therefore supports interpretation of the threshold outcome, but not a fuller account of the distribution of infection prevalence within or across communities.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is a count-based community outcome: communities are classified according to whether infection prevalence among children ages 1 to 9 years is at or below 1% at the 24-month survey. General statistical explanation: a binary classification can be analysed by comparing the odds that a community meets the threshold in one arm with the odds in the other. The odds ratio expresses that relative comparison. An odds ratio of 1 represents equal odds; values above or below 1 point toward higher or lower odds in the first arm, according to the comparison’s direction.

The registry reports an odds ratio of 2.6 from logistic regression, with a 95% confidence interval of 0.56 to 11.9. General statistical explanation: logistic regression models the log odds of a binary outcome and can estimate an odds ratio for a group comparison. The registry’s short method label does not establish which covariates, if any, were included, how standard errors were calculated, or whether the analysis accounted for any additional community-level structure. Those specifications are not reported in the registry record.

A confidence interval describes the uncertainty around an estimated quantity under the analysis assumptions. The reported interval is broad and includes 1, the value corresponding to equal odds. That means the interval does not isolate a single direction of association: values on either side of 1 are compatible with the reported interval. A wide interval can indicate limited precision, but the registry record does not state why this interval is wide or provide a separate precision analysis. The p-value is reported as p >0.05. General statistical explanation: a p-value measures how unusual data at least as inconsistent with a specified null model would be if that model were true, subject to the analysis assumptions. It is not the probability that the null hypothesis is true, and it does not measure the size or practical importance of a difference.

Because communities were randomized, the assigned community is the unit relevant to the primary comparison. The children’s infection measurements contribute to the community-level prevalence classification, but the posted endpoint does not treat each child as an independent randomized unit. General statistical explanation: analyses should respect the unit of randomization; treating observations from the same randomized unit as independent can make uncertainty estimates inappropriate. The registry record does not report the underlying child-level data or the exact procedure used to calculate each community’s prevalence.

The arm results list 7 communities meeting the threshold in the intervention group and 4 in usual care, with 26 communities in each arm. Those counts describe the observed endpoint. They should not be mistaken for the logistic-regression estimate: the odds ratio is the reported model-based comparison, and its confidence interval and p-value express inferential uncertainty. A separate unadjusted recalculation is not reported in the registry record.

General statistical explanation: when outcomes are counts or proportions, variability may differ from the assumptions of simple models. Over-dispersion means that observed variation exceeds what a model’s assumed distribution predicts; accounting for it can affect standard errors and confidence intervals. The registry does not report whether over-dispersion was assessed or whether an adjustment for it was used. It would be inappropriate to claim that it was present or absent based on the posted summary.

The record gives a superiority classification for the analysis. In a superiority framework, the analysis asks whether the intervention strategy differs in the intended direction from the comparator under the chosen statistical test. The record does not provide a full statistical analysis plan, the precise null and alternative hypotheses, or a prespecified minimum important effect. The reported p-value above 0.05 and confidence interval including 1 do not establish superiority in this analysis.

The registry’s sample-size assumptions describe planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is expressed as a fraction of the observed effect. Such calculations are planning illustrations, not observed power and not evidence about the trial’s original design. The registry record does not report the original sample-size justification or state that the planning assumptions were the trial’s design assumptions.

Finally, statistical interpretation depends on how outcomes, populations, missing observations, and model choices were handled. The registry record does not report a detailed analysis population, handling of missing outcome data, or sensitivity analyses. Those omissions limit the ability to assess whether the reported estimate is robust to alternative analytic choices.

10. Analyses Reported by the Sponsor

The posted comparison is the registry-reported logistic regression result: odds ratio 2.6, 95% confidence interval 0.56 to 11.9, and p >0.05. A separate unadjusted recalculation is not reported in the registry record. The posted arm counts alone do not provide the same model-based result or its uncertainty, and no additional recalculated estimate should be substituted for the sponsor’s reported analysis.

The registry record does not identify a discrepancy between a recalculation and the sponsor’s analysis. The sponsor’s own analysis therefore remains the relevant reported inferential result. It is imprecise, with a confidence interval that includes 1, and the reported p-value is above 0.05. The point estimate is not, by itself, evidence that the intervention caused a difference. More detailed model specifications or a fuller sponsor analysis are not reported in the registry record.

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists one primary outcome and two secondary outcomes. The primary outcome is the proportion of communities with C. trachomatis infection prevalence at 1% or below at 24 months. The secondary outcomes concern the proportion of communities with clinical trachoma prevalence of 5% or below and the mean prevalence of active trachoma (TF) in communities in both arms. Results for the secondary outcomes are not included in the posted results described in the record.

Multiplicity arises when several outcomes, comparisons, or analyses are examined. General statistical explanation: with multiple statistical tests, the chance of at least one apparently positive result can increase unless the analysis plan addresses that issue. The registry record does not report whether multiplicity adjustments were planned, whether one outcome was designated as the sole basis for a confirmatory claim, or how the secondary outcomes were intended to be interpreted. No adjustment or testing hierarchy should be assumed.

The record does not report how missing outcome data were handled, whether any communities lacked a 24-month assessment, or whether sensitivity analyses were conducted. It also does not report the analysis population in detail, such as whether the primary analysis followed assignment regardless of subsequent participation or treatment. These omissions matter because missing outcomes and analysis-population decisions can affect both the estimated comparison and its uncertainty.

The registry states that 38 of the 52 communities identified as at risk at 18 months were to be surveyed at 30 months, following a Data Safety and Monitoring Committee recommendation in March 2015. This is a description of later follow-up and should not be interpreted as a statement about missing 24-month primary-outcome data. The record does not give further reasons for the follow-up arrangement or its implications for the primary analysis.

The full statistical analysis plan, interim-analysis procedures, and any rules for handling deviations from the planned analysis are not reported in the registry record. As a result, the available information does not establish whether multiplicity, missingness, or analysis-population choices were addressed in a prespecified way.

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 0% reporting threshold.

The registry reports zero serious adverse events affecting participants in each arm. It lists 26 participants at risk in the intervention group and 26 in the usual-care group, with zero serious events in each. It also lists zero other adverse events affecting participants in each arm and zero deaths in each arm.

These figures are counts as recorded, not evidence that no adverse effects of any kind occurred. The registry record does not provide serious-event terms, event definitions, collection procedures, severity grading, or follow-up details. It lists no top serious-event terms. The absence of listed events should therefore be interpreted as no events reported in these registry fields, rather than as proof that the strategies have no safety risks.

The record also does not explain whether the safety assessment covered all participants for the same duration or how events were attributed to an intervention. The arm-level counts are descriptive and do not provide a detailed comparative safety analysis. They should be read separately from the primary infection-prevalence outcome.

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

The primary result describes whether communities crossed a specified infection-prevalence threshold at the 24-month survey. The posted arm counts were 7 communities in the intervention arm and 4 in usual care, out of 26 listed in each arm. The registry’s logistic-regression estimate was an odds ratio of 2.6, with a 95% confidence interval from 0.56 to 11.9 and p >0.05. The interval is broad and includes equal odds, so the estimate is not precise enough to establish a clear difference in the reported superiority analysis.

These results do not show that the intervention caused more communities to meet the threshold. Random assignment supports a comparison of assigned strategies, but the registry-reported estimate remains uncertain. Nor do the results establish that the strategies are equivalent: an inconclusive result is not the same as evidence of no difference. The registry does not report an equivalence or non-inferiority design.

The outcome is a community-level threshold, not an individual-level clinical outcome. It does not show the average infection prevalence among children, the number of children infected, how far each community was from the cutoff, or the duration of any change. The record also does not provide the underlying prevalence measurements needed to assess those questions.

The trial compares usual care with usual care plus a newcomer/traveler surveillance and treatment program. It does not compare mass drug administration with no treatment: the MDA rules are described for both arms. Interpretation should therefore focus on the added program within that care framework, not on azithromycin treatment in general.

The registry’s secondary outcomes are listed without results, and details on missing data, model specifications, and multiplicity are not reported. Those gaps limit broader conclusions about other aspects of trachoma prevalence or the reliability of alternative analyses. The posted data support a cautious reading of one community-level comparison at one stated survey time; they do not settle wider questions about treatment policy or individual health outcomes.

14. Why This Trial Matters Statistically

This trial is statistically useful because its randomization and primary outcome operate at the community level. The intervention is a community strategy added to usual care, and the endpoint asks whether communities meet a prevalence threshold. Keeping the unit of randomization and the unit of the endpoint clear is essential: the result is not a comparison of individually randomized children.

The study also illustrates how threshold outcomes can align with practical program decisions while simplifying the underlying data. A cutoff such as infection prevalence at 1% or below gives a clear classification, but it does not retain information about how close a community is to the threshold or how prevalence varies within a community. That distinction helps explain why the endpoint should not be interpreted as a comparison of average infection burden.

The uncertainty is an important part of the result. The reported odds ratio is 2.6, but the confidence interval from 0.56 to 11.9 is broad and crosses 1, with p >0.05. Reading the point estimate without the interval would overstate precision. The result also demonstrates that a non-significant analysis does not establish equivalence or rule out a potentially important difference.

Finally, the registry record makes clear why detailed reporting matters. Without the analysis plan, handling of missing data, model specification, and results for secondary outcomes, readers cannot fully assess the scope or robustness of the conclusions. The trial’s community-level question is clear, but the posted information leaves important parts of the statistical interpretation unresolved.

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 registry record gives limited detail about the statistical analysis. It identifies logistic regression but does not report the full model specification, any adjustment variables, the method used for standard errors, or whether the analysis accounted for additional community-level structure. The randomization sequence and allocation concealment are also not described. These omissions restrict independent assessment of the reported odds ratio and its uncertainty.

The primary endpoint reduces prevalence to a threshold classification. The record does not provide the underlying community prevalence values, so readers cannot assess how close communities were to the cutoff or compare the distribution of prevalence between arms. The endpoint also does not report child-level infection outcomes as a separate result.

The registry does not report a detailed analysis population, missing-data methods, sensitivity analyses, or multiplicity procedures. Results for the two listed secondary outcomes are not included in the posted results described in the record. The reason for the broad confidence interval is not reported, and the available summary does not establish whether alternative analytic approaches would change the estimate.

The 30-month follow-up description concerns 38 communities identified as at risk at 18 months and follows a Data Safety and Monitoring Committee recommendation in March 2015. The registry does not provide the later outcome results in the registry record for this analysis. That follow-up information cannot fill gaps in the 24-month primary comparison.

Finally, the arm descriptions are truncated in the registry record, and the operational details of surveillance and treatment for newcomer and traveler families are not fully reported. The available description is sufficient to identify the intended contrast, but not to assess implementation fidelity or variation in how the added program was delivered across communities.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Surveillance and Azithromycin Treatment for Newcomers and Travelers Evaluation: The ASANTE Trial — NCT01767506.
• Registry record last updated 2017-10-09; status last verified 2017-10.
• Results first posted 2017-10-09.
• 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

ASANTE was a completed, randomized, parallel-group community trial in Kongwa, Tanzania, with 52 communities listed. It compared usual care with usual care plus surveillance and azithromycin treatment for newcomer and traveler families. The primary outcome was the proportion of communities with C. trachomatis infection prevalence at 1% or below among children ages 1 to 9 years at 24 months.

The registry reports that 7 of 26 intervention communities and 4 of 26 usual-care communities met the threshold. The logistic-regression odds ratio was 2.6, with a 95% confidence interval of 0.56 to 11.9 and p >0.05. This estimate is imprecise and does not establish a statistically significant difference in the reported superiority analysis. Details on missing data, multiplicity, and the full analysis specification are not reported in the registry record.