Atlas:Text Messaging Program With Weather Alerts, Local Resources & Insights for Addressing Climate Change: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Atlas:Text Messaging Program With Weather Alerts, Local Resources & Insights for Addressing Climate Change (NCT06995755), a na na study. The primary outcome is Response Efficacy Scale.

2. Clinical Question

3. Trial Design

Atlas is a completed, single-group behavioral study of an interactive text messaging program about climate change. The registry record lists an enrollment of 54. All participants were provided access to atlas; there was no separate comparison arm. Allocation is listed as NA, and masking is listed as none. This design can describe what was observed among participants using the program, but it cannot separate changes over time from other influences as a controlled comparison could.

The intervention combined several components. It delivered information on current climate-related and environmental risks that might affect users’ health conditions, including examples such as high temperatures, air quality alerts and asthma triggers. It linked users to local ZIP-code-matched resources, with cooling centers and hurricane shelters as examples. It also tailored ongoing communications about human actions and extreme weather to users’ concern about and belief in climate change, and offered customized tips for action at individual, community and policy or advocacy levels according to motivation.

The primary outcome was the Response Efficacy Scale, measured at pretest and posttest, with the posttest scheduled at 30-day follow-up. The primary outcome population is described as users who completed both assessments and did not score 15, the maximum on the scale. The registry record lists 36 users in that population. The trial is marked completed, with start and primary completion dates of 2024-06-25 and 2024-08-21. The registry record does not report a control condition, allocation procedure beyond NA, or further details about how participants were recruited or followed.

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: 36 users completed baseline \& follow-up and did not have a maximum score on response efficacy measure (a score of 15), in which case they were excluded from the primary outcome analyses.

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 Response Efficacy Scale, measured over Pretest (baseline) and Posttest (30 day follow-up).

The primary endpoint was the Response Efficacy Scale, a 3-item measure of perceived efficacy for mitigating climate change at individual, community and governmental or policy levels. It uses a Likert scale with total scores ranging from 3 to 15; higher scores represent a better outcome according to the registry description. The measure is intended to capture whether people believe actions at these different levels can contribute to climate change mitigation.

Assessments were scheduled at baseline and at 30-day follow-up. Repeated measurement makes it possible to describe how scores differ between the two assessment times among users with measurements at both times. However, in a single-group study, a pretest-to-posttest difference by itself does not establish that the program caused a change. Other changes over time, participant expectations, or the experience of taking part may also be relevant, and there is no control group in this trial to distinguish these explanations.

The registry record states that users with the maximum score of 15 were excluded from the primary outcome analyses, along with the requirement to have completed baseline and follow-up. A maximum score leaves no room for a higher observed score on this scale, which can limit the ability to observe improvement for those users. Numerical scale results and the estimated change are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

For a continuous outcome such as a scale score, a mean describes the average score in a group, while a standard deviation describes the spread of individual scores around that average. The registry record identifies the primary outcome as a mean with standard deviation. Those summary statistics would help describe scores at baseline and follow-up, but the registry record does not report their values.

What does a pretest-to-posttest comparison represent?

When the same users are assessed at two times, an analysis may focus on within-person changes, or it may report the group mean at each time and a contrast between them. These approaches answer related but not identical descriptive questions. A within-person analysis uses the fact that repeated observations belong to the same person; a comparison of separate time-specific summaries may not express that pairing in the same way. The registry record does not report which analytical approach was used, or any estimate of change.

In general, a confidence interval describes a range of values compatible with the data and a specified statistical procedure. Its width conveys precision: wider intervals indicate less precision than narrower intervals. A confidence interval does not by itself establish that an effect is causal or practically important. No confidence interval for the primary outcome is reported in the registry record, so the precision of the outcome estimate cannot be assessed from it.

What can a single-group design tell us?

A single-group pretest and posttest design can describe how measured scores differ over time among participants who contribute assessments. It does not provide a concurrent untreated or alternative-treatment group. Consequently, any difference over time may reflect influences other than the intervention. This is a general limitation of the design, not evidence that any particular outside influence occurred in this study. Randomized allocation and a suitable comparison group can support stronger between-group causal comparisons, but this record describes neither a randomized comparison nor a second arm.

In this trial, the primary analysis population is defined by completion of both assessments and absence of the maximum score. Requiring both assessments means that users without a follow-up measure cannot contribute to a simple paired comparison. Excluding maximum scores also changes the target group for the primary analysis: the result would describe the specified eligible users, not necessarily everyone enrolled. The record does not report a separate analysis including users with maximum scores or a method for addressing incomplete measurements.

How should the scale be understood?

The Response Efficacy Scale has 3 items and a possible total from 3 to 15, with higher scores described as better. A score at the maximum cannot increase on the stated scale, so excluding users at 15 may avoid a ceiling constraint in the primary outcome analysis. However, exclusion also means the analysis does not represent users at that maximum. The registry record does not report how many of the users who completed both assessments had a maximum score, or the distribution of scores at either time.

The primary outcome is a continuous score, not a count of events or a time-to-event measure. The registry record gives no outcome analysis estimates, test statistics, p-values, or confidence intervals, and lists no analyses. It is therefore not possible to explain the result using an inferential test or determine whether an analysis adjusted for other variables. Such details are not reported in the registry record.

General sample-size planning often considers a target effect, variability, significance level, allocation and desired power. The registry record describes a planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms and a normal approximation. It also describes planning for fractions of the observed effect. These are planning assumptions, not evidence that this single-group trial had two arms or that its study design used those assumptions. Numerical planning outputs and the observed primary effect are not reported in the registry record. Planning illustrations should not be read as observed power or as a substitute for outcome estimates and their uncertainty.

Over-dispersion is a general concern for count outcomes when variability exceeds what a simple count model assumes; it can affect standard errors and confidence intervals if not handled appropriately. The primary endpoint in this trial is a continuous scale score, and the registry record does not describe a count-outcome analysis. No claim about over-dispersion methods or their use can therefore be made for this primary outcome. More broadly, the statistical analysis plan, model specification, handling of missing data and any adjustment strategy are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists two outcome measures: the primary Response Efficacy Scale and a secondary outcome named Confidence. It does not report the numerical results for either outcome, nor does it list analyses. The record does not report whether any multiplicity adjustment was planned or used. When multiple outcomes or multiple tests are considered, the chance of at least one apparently unusual result can increase; adjustment methods are one general way to address that issue. Without the analysis details and outcome results, it is not possible to determine whether multiplicity was relevant to any reported inference in this study.

The primary outcome population is defined as users who completed baseline and follow-up and did not have a maximum score of 15. The registry record identifies 36 users in this population. Enrollment is listed as 54, but the record does not separately quantify the number without follow-up and the number excluded for a maximum score. It also does not describe additional missing-data patterns or explain how any incomplete observations were handled.

In general, excluding participants with missing follow-up can produce a result that differs from one based on all enrolled participants if completion is related to their outcome. This is a methodological possibility, not a claim about why any user did or did not complete follow-up. The record does not report imputation, sensitivity analyses, or a broader analysis population that would show how conclusions might change under different assumptions about missing outcomes.

The maximum-score exclusion is a separate feature of the stated primary analysis population from missing follow-up. It limits the analysis to users with room to score higher on the scale, but also narrows the group described by the outcome analysis. The registry record does not report an analysis including users with a score of 15, so the results for that group cannot be assessed.

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.

The registry record lists serious adverse events and other adverse events for Atlas Users. For each category, 54 users are listed as at risk and 0 as affected. Deaths are listed as 0. No serious adverse event terms are listed. These are the event counts recorded for the study, not estimates of comparative risk between treatments.

Because the study has a single group, these figures do not allow a comparison with a control group or another intervention. A count of 0 recorded events means that no events in that category are listed as having affected participants in this registry record; it does not establish that the underlying risk is zero. The registry record does not provide a comparison group, a causal safety analysis, or further event descriptions. It also does not provide enough information to evaluate the completeness of event ascertainment or the precision of a risk estimate.

Adverse event summaries should be read separately from the primary response efficacy outcome. The event counts do not indicate whether response efficacy changed, and they do not measure the program’s effect on climate-related health risks. They describe only the adverse event information reported in the registry record.

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

Atlas was evaluated as an interactive text messaging program that combined weather and environmental risk information, ZIP-code-matched local resources, tailored communication and action tips. Its stated primary outcome was response efficacy for mitigating climate change, measured at baseline and 30-day follow-up. The registry record describes the measure, its scale and the primary analysis population, but does not report numerical outcome results.

Without baseline and follow-up summaries or an estimated change, the direction and magnitude of any difference cannot be determined. Without uncertainty estimates, the precision of a difference cannot be assessed. The record lists no analyses, so it does not support a conclusion about statistical significance. These absences do not mean that the measured score did not change; they mean that the change is not reported in the registry record.

The single-group structure is important to interpretation. Even if a pretest-to-posttest difference were available, it would describe change over time in the analyzed group rather than a controlled comparison. It would not, on its own, establish that atlas caused the change. The record does not include a randomized or nonrandomized comparison arm against which to evaluate the program.

The endpoint is a measure of perceived efficacy across individual, community and governmental or policy levels. It is not a direct measure of climate-related illness, local weather exposure, use of community resources, behavior change, or environmental impact. The intervention description includes these topics and aims, but the registry record does not report numerical findings on those outcomes.

The record also identifies an analysis population that excludes users who had a maximum score of 15 and requires completion of both assessments. That definition affects whom the primary outcome is intended to describe. It does not, by itself, reveal why other enrolled users were not included. The reported adverse event counts are separate from efficacy and do not resolve the missing outcome information. The defensible interpretation is therefore limited to the recorded design, outcome definition, analysis population and adverse event counts; claims about benefit, lack of benefit or causal effects are not supported by the reported outcome results.

13. Why This Trial Matters Statistically

This trial raises useful statistical questions about how to evaluate an intervention whose components are tailored to users. Atlas combines environmental information, locally matched resources and behavior-change messages, while its primary outcome measures perceived efficacy for climate mitigation. The distinction between intervention content and measured endpoint matters: an outcome about perceived efficacy does not automatically establish changes in behavior, environmental exposure or health.

The design also illustrates the limits of interpreting change over time without a comparator. Baseline and follow-up measurements can describe an outcome trajectory among participants, but they cannot isolate the program’s contribution in the way a suitable controlled comparison can. This distinction is important when describing what a study can support, especially when the registry record does not report the numerical outcome estimates.

The stated analysis population highlights another issue. The primary outcome analysis requires completion at both times and excludes users at the score maximum. This can be relevant for understanding the group represented by any estimate, as well as how missing follow-up and scale ceilings affect interpretation. The registry record does not provide enough detail to quantify those separate features beyond its stated population and enrollment.

Finally, the record makes clear why reporting estimates and their uncertainty matters. An outcome definition and a study design alone do not reveal the direction, size or precision of a result. The registry record does not report numerical primary outcome findings or analyses, so a statistical assessment of the observed response efficacy result is not possible. The case is therefore informative about the questions readers should ask of a single-group pretest-posttest evaluation, while its posted outcome information remains insufficient to answer those questions about the result itself.

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 central limitation for interpreting the primary outcome is that numerical results are not reported in the registry record. The record does not give baseline or follow-up means, standard deviations, an estimated change, a confidence interval, or a test result. It lists no analyses. The size, direction and precision of any observed response efficacy change therefore cannot be evaluated.

The single-group design has no concurrent comparator and is not a randomized comparison. A difference between baseline and follow-up, if reported, would not by itself identify the effect of atlas. The registry record also does not report details of recruitment, participant characteristics, adherence to the messages, or use of the local resources, limiting assessment of who the findings might describe and how participants experienced the intervention.

The stated primary outcome population includes 36 users who completed both assessments and excludes users with the maximum score of 15. Enrollment is listed as 54. The record does not separate the number excluded because of incomplete follow-up from the number excluded for a maximum score, describe other exclusions, or report analyses that examine these groups. This prevents assessment of how the stated eligibility criteria may affect the outcome estimate.

The registry record does not describe the statistical analysis plan, handling of missing data, multiplicity procedures, or sensitivity analyses. It also does not provide numerical results for the secondary outcome named Confidence. The adverse event summary lists zero affected users for serious and other adverse events and zero deaths, but does not provide further event details or a comparison group. These limits restrict both efficacy interpretation and comparative safety assessment.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Atlas:Text Messaging Program With Weather Alerts, Local Resources & Insights for Addressing Climate Change — NCT06995755.
• Registry record last updated 2025-06-26; status last verified 2025-06.
• Results first posted 2025-06-26.
• 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 registry record describes Atlas as a completed, single-group behavioral study of an interactive text messaging program addressing climate change. Enrollment is listed as 54, and all participants were provided access to atlas. The study had no masking and no randomized comparison arm.

The primary outcome was the Response Efficacy Scale, a 3-item measure with scores from 3 to 15, measured at baseline and 30-day follow-up. The stated analysis population comprises 36 users who completed both assessments and did not have the maximum score of 15. Confidence is listed as a secondary outcome. Numerical outcome findings and analyses are not reported in the registry record.

The adverse event summary lists 0 serious adverse events, 0 other adverse events and 0 deaths. These are single-group counts and do not provide a comparative safety estimate. The design and missing numerical outcome results limit conclusions about efficacy or causation.