TEAMS-BP (The Enhancement of Social Networks to Augment Management of Stroke-Blood Pressure): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for TEAMS-BP (The Enhancement of Social Networks to Augment Management of Stroke-Blood Pressure) (NCT05258890), a randomized na study. The primary outcome is Change in Systolic Blood Pressure for Patient-Subjects.

2. Clinical Question

3. Trial Design

TEAMS-BP was registered as a randomized, double-masked, parallel-group trial. The listed interventions were social network group counseling and individual counseling. The registry record lists enrollment as 64 and the study status as terminated. The start date was 2022-05-31, and the primary completion date was 2024-01-26. The reason for termination is not reported in the registry record.

Participants were described as stratified according to network size (<5 versus 5 or more) and randomized to one of the counseling approaches. The social network intervention involved the patient and influential social network members; the individual intervention involved the patient alone. Both descriptions specify remote meetings with a clinical research nurse 3 times over the course of 3 months. The record labels masking as double but does not identify which individuals or study personnel were masked, or explain how masking was maintained.

The posted primary outcome is change in systolic blood pressure for patient-subjects, measured at baseline and 3 months. Its statistical summary is a mean with standard deviation. The outcome description explicitly states that blood pressure was not collected for social network members. Two secondary outcomes are listed: achievement of a post-stroke hypertension treatment goal and patient-reported physical function. Numerical results for those secondary outcomes are not reported in the registry record.

The outcome entries report 24 patients in the social network counseling arm and 21 in the individual counseling arm. The record does not explain how those outcome entries relate to the enrollment figure or identify the analysis population. The trial’s original sample-size justification, detailed statistical analysis plan, and reason for stopping are not reported in the registry record.

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: A total of 47 patients enrolled, but 2 patients withdrew prior to randomization. Social network members were only enrolled in the social network counseling arm. All consented patients' social network members were collected in the baseline questionnaire, prior to randomization. For patients who were randomized to individual counseling (n=21), network members were not enrolled. For patients who were randomized to social network counseling (n=24), network members were enrolled (n=17).

Overall Study

Reasons for not completing this period:

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: Baseline Characteristics were not collected for social network members.

6. Primary Endpoint

The registry lists the primary outcome as Change in Systolic Blood Pressure for Patient-Subjects, measured over baseline and 3 months.

The primary endpoint is change in patient systolic blood pressure from baseline to 3 months, expressed in mmHg. The registry describes it as the mean change and gives a standard deviation for each arm. A negative change represents a decrease from baseline; the posted arm means are -10.82 for social network counseling and -5.31 for individual counseling. Blood pressure was not collected for social network members, so the endpoint reflects the patient-subjects rather than the broader social network.

Blood pressure is used as a continuous measure, allowing the comparison to retain the magnitude of change rather than reducing each patient’s result to a category. The registry also lists achievement of a post-stroke hypertension treatment goal as a secondary outcome. That categorical outcome can address whether patients reached a specified target, while the continuous endpoint describes the amount of measured change. Patient-reported physical function is another listed secondary outcome. Numerical findings for these secondary outcomes are not reported in the registry record.

Interpreting change requires attention to the measurement interval and to how the analysis handles baseline values, missing follow-up measurements, and any repeated measurements. Those details are not reported in the registry record. The primary outcome is specified at baseline and 3 months, but the record does not explain whether the posted group summaries include all randomized participants or only those with available measurements.

7. Results Posted in the Registry

• Individual Counseling: mean -5.31 versus -10.82 on control; difference 5.51 (95% CI 2.20 to 8.82), standardized effect d = 0.99; z-test p = 0.001.

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is continuous: systolic blood-pressure change is reported in mmHg as a mean and standard deviation for each arm. A mean describes the central value of the observations in an arm; a standard deviation describes variation among those observations. In general, these summaries are useful for comparing average changes, but they do not show the full distribution or reveal whether values were skewed, clustered, or influenced by unusual observations. The registry does not report individual-level data or distributional diagnostics.

The posted comparison is an unadjusted difference in means. Its reported direction is individual counseling relative to social network counseling, and the estimate is 5.51 mmHg. The arm means are -10.82 and -5.31 mmHg, respectively. An unadjusted comparison uses the reported group summaries without a stated covariate adjustment. The registry record does not report adjustment for baseline blood pressure, network-size stratum, or other characteristics, and it does not describe a model used for the comparison.

In general, randomization is intended to make treatment groups comparable on average, including with respect to measured and unmeasured factors. Randomization does not guarantee exact balance in a particular trial, especially when the number of observations is limited. The registry describes random allocation and stratification by network size, but it does not give the randomization procedure, allocation concealment details, or the method used to account for stratification in the endpoint analysis.

The record reports standard deviations of 5.08 and 6.1 for the social network and individual counseling arms. Those quantities describe spread within each group; they are not standard errors for the means. The record also gives a standard error for each arm mean, 1.037 and 1.331, respectively. A standard error describes the sampling uncertainty of an estimate under the statistical model used. The methods used to derive the posted standard errors and confidence interval are not described in the registry record.

In general, a confidence interval combines an estimate with its uncertainty to express a range of values compatible with the data under specified assumptions. The reported 95% confidence interval for the mean difference is 2.203 to 8.817 mmHg. It is not a probability statement that the true difference has a 95% chance of lying in that particular interval. Its interpretation relies on the analysis assumptions, including the way observations were selected and the model used to estimate uncertainty. Those details are not fully reported in the registry record.

The unadjusted p-value is 0.001. In general, a p-value measures how unusual data at least as incompatible with a specified null hypothesis would be under that hypothesis and the analysis assumptions. It is not the probability that the null hypothesis is true, nor a measure of clinical importance. The registry does not describe whether the p-value came from a t-test or another procedure, whether assumptions were checked, or whether the reported comparison was prespecified in a statistical analysis plan.

Missing-data handling is particularly relevant because the reported endpoint group sizes differ from the enrollment figure. The record does not state whether the analysis followed an intention-to-treat approach, whether participants without follow-up measurements were excluded, or whether any imputation or sensitivity analysis was used. In general, simply analyzing observed measurements can introduce bias if availability of follow-up is related to outcome or group assignment. The registry record does not provide enough information to evaluate that possibility.

For the primary endpoint, the record reports a baseline-to-3-month measurement interval. It does not state whether there were other blood-pressure measurements, how measurement procedures were standardized, or how repeated values were combined. It also does not report baseline arm summaries, which would help readers assess starting values and understand whether the change comparison was adjusted for baseline.

The trial is marked double-masked, but the masked roles and procedures are not reported. The interventions themselves involve different participation arrangements, and the record does not explain how masking applied to patients, clinicians, outcome assessors, or analysts. No statistical analysis plan, interim analysis information, or multiplicity procedure is reported in the registry record. These omissions limit assessment of prespecification and the interpretation of the unadjusted primary comparison.

Finally, the record lists two secondary outcomes but does not post numerical results for them. No multiplicity adjustment is reported. In general, considering multiple outcomes can increase the chance of at least one apparently notable result when each is tested separately. Without the analysis plan and complete secondary results, it is not possible to determine how the trial’s full set of outcome analyses was handled.

10. Confidence Intervals and Precision

The unadjusted estimated difference in mean systolic blood-pressure change is 5.51 mmHg, with a 95% confidence interval from 2.203 to 8.817 mmHg. The interval stays on the positive side of zero, in the direction of a less negative mean change for individual counseling relative to social network counseling. The unadjusted p-value is 0.001. These quantities describe the posted comparison; they do not resolve limitations in the reported analysis details.

In general, a confidence interval communicates precision by showing how much uncertainty surrounds an estimate under the statistical assumptions used. A narrower interval indicates greater precision than a wider interval, while an interval spanning a broad range leaves more uncertainty about the size of the contrast. The interval gives a range of plausible values under the analysis assumptions, rather than a guarantee about the true effect or a measure of the probability that any particular value is correct.

The registry record does not state the method used to construct the interval, whether it was adjusted for stratification, or how missing outcomes were handled. The arm summaries report standard deviations of 5.08 and 6.1, and standard errors of 1.037 and 1.331. The reported outcome counts are 24 and 21. The record does not explain whether these counts represent all randomized participants, participants with complete measurements, or another analysis population. That uncertainty affects how readers assess the interval’s applicability.

Precision is distinct from clinical importance. The registry record does not define a clinically important difference for this endpoint. The interval and p-value should therefore be interpreted as statistical descriptions of the observed comparison, not as evidence about whether a difference is important to patients or care decisions.

11. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are participants per arm, not total event counts. They are illustrations based on the observed difference and are not the trial’s original sample-size calculation. The stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Each planning row uses a stated fraction of the observed effect as the effect to detect.

For planning for 100% of the observed effect, the entries are 17 participants per arm for 80% power and 22 participants per arm for 90% power. For planning for 75% of the observed effect, the corresponding entries are 29 participants per arm and 39 participants per arm. For planning for 50% of the observed effect, they are 65 participants per arm and 87 participants per arm.

In plain language, the 80% power column gives the approximate number of participants per arm that would be needed, under the stated assumptions, to have an 80% chance of detecting the chosen effect if that effect were real. The 90% power column describes the corresponding planning target for a 90% chance. These are prospective planning illustrations, not observed power for the completed trial. Smaller effects require more participants to detect under the same assumptions, which is why the entries increase as the assumed fraction of the observed effect decreases.

The curve presents the planning relationship visually under these assumptions. The figures depend on the observed effect used as their reference, which may be an unstable basis for planning in a small study. The trial’s own original design assumptions and sample-size justification are not reported in the registry record.

12. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = 5.510; pooled standard deviation σ = 5.578.
2. n = 2 × (1.96 + 0.842)² × 5.578² / 5.510² = 16.1, rounded up to 17 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- 5.51                      # observed difference in means
sigma <- 5.57766976433707                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(5258890)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 17 (80% power), 22 (90% power)
 75% of observed effect: n per arm = 29 (80% power), 39 (90% power)
 50% of observed effect: n per arm = 65 (80% power), 87 (90% power)
power.t.test: 17.1 
Simulated power at n = 17 per arm: 0.799 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

13. Multiplicity, Missing Data and Analysis Populations

The registry record lists the primary blood-pressure change outcome and two secondary outcomes: achievement of a post-stroke hypertension treatment goal and patient-reported physical function. Numerical results for the secondary outcomes are not reported in the registry record. No multiplicity adjustment or hierarchy for testing outcomes is described.

In general, testing multiple outcomes or multiple comparisons can increase the chance of observing a statistically notable result by chance if each test is interpreted separately. A prespecified plan can address this through a defined testing hierarchy or adjustment. The registry record does not report whether such a plan was used, so the unadjusted p-value for the primary comparison should not be treated as a complete account of the study’s outcome-testing strategy.

The registry does not identify the analysis population or explain how participants with missing blood-pressure measurements were handled. The enrollment field lists 64, while the primary endpoint entries give arm counts of 24 and 21. The reason for this difference and the relationship between these figures are not reported in the registry record. There is no reported account of withdrawals, missingness by arm, imputation, or sensitivity analyses.

The record also does not state whether analysis followed intention to treat, whether the comparison adjusted for baseline blood pressure or the network-size strata, or whether any per-protocol population was defined. The randomization and stratification description alone does not establish how those design features were incorporated into the outcome analysis.

The registry lists no posted statistical analyses, while giving an unadjusted comparison for the primary endpoint. This does not establish that no analyses were conducted; it means the registry record does not document a fuller analysis plan or set of results. Information on interim analyses, stopping rules, outcome deviations, and prespecified handling of missing data is not reported in the registry record.

14. 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: acute/subacute ischemic stroke (9.5%), planned surgery of carotid artery (4.2%).

The serious adverse event entries report 1 event among 24 participants at risk in the social network counseling group and 2 among 21 participants at risk in the individual counseling group. Deaths are recorded as 0 in each group. Other, non-serious adverse events are recorded as 0 in each group. These are the registry’s posted counts and should be read alongside the listed at-risk counts for each arm.

The registry lists acute/subacute ischemic stroke at 9.5% and planned surgery of carotid artery at 4.2% among its top serious-event terms. The record does not clearly state the denominator or arm attribution for these term percentages. It also does not provide detailed narratives, timing, relatedness assessments, or an explanation of how events were collected. These figures therefore describe the posted safety entries, not a complete account of event context or comparative risk.

In general, adverse-event counts are descriptive unless the study reports a specified comparative analysis. Differences in counts alone do not establish whether an intervention caused an event or whether the groups’ event experience differed beyond chance. No treatment recommendation follows from these registry entries.

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

The posted primary outcome shows mean systolic blood-pressure changes of -10.82 mmHg with social network counseling and -5.31 mmHg with individual counseling from baseline to 3 months. The unadjusted contrast is 5.51 mmHg for individual counseling relative to social network counseling, with a 95% confidence interval from 2.203 to 8.817 and an unadjusted p-value of 0.001. These statistics describe the recorded comparison for this trial.

The result does not by itself establish what would occur in other settings or populations. The registry does not report participant characteristics in enough detail to assess how representative the enrolled group was, and it does not explain how the primary endpoint analysis population was formed. The registry status is terminated, but the reason for termination is not reported. These limitations complicate assessment of how broadly the result can be applied.

The posted primary endpoint is not the same as achievement of a treatment goal or patient-reported physical function. Although both are listed as secondary outcomes, their results are not reported in the registry record. The available numerical findings therefore cannot answer whether either secondary outcome differed between groups.

The estimate and confidence interval are statistical summaries, not direct measures of importance to patients. The registry record does not specify a clinically important difference for systolic blood-pressure change. The unadjusted p-value does not express the probability that either counseling approach is beneficial, nor does it establish that the observed group contrast is causal under every possible source of bias.

In general, interpretation of a randomized trial also depends on complete outcome reporting, the analysis population, adherence, missing data, and whether the reported analysis matches a prespecified plan. Several of those details are not reported in the registry record. The posted results are best understood as evidence about the recorded mean changes and their unadjusted comparison, with uncertainty about analysis details and the unreported secondary outcomes.

16. Why This Trial Matters Statistically

TEAMS-BP addresses a statistical question that goes beyond whether counseling was delivered to patients individually or with network members present: it compares mean change in a continuous clinical measure between randomized groups. The endpoint preserves the magnitude and direction of blood-pressure change, while the listed secondary outcomes address a treatment-goal category and patient-reported function. These outcome types answer related but distinct questions.

The registry describes randomization and stratification by network size. In general, stratification can help balance a factor considered relevant to outcomes, while randomization supports a fair comparison. To interpret that design fully, however, readers need to know how the analysis accounted for the strata, what population was analyzed, and how missing measurements were handled. Those details are not reported in the registry record.

The comparison also illustrates why an estimate should be read together with its confidence interval. The posted difference is 5.51 mmHg, and its 95% confidence interval ranges from 2.203 to 8.817 mmHg. The interval gives information about precision that the p-value alone does not convey. At the same time, neither statistic establishes clinical importance, which is not defined in the registry record.

The record’s missing analysis details and absent secondary results matter statistically because they limit assessment of multiplicity, selection into the analyzed sample, and the completeness of outcome reporting. The planning illustrations further show that sample-size requirements depend on the effect chosen for planning: smaller assumed effects require more participants per arm under the stated assumptions. This distinction helps separate the observed estimate from prospective study planning.

17. 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 explain why the trial was terminated. It gives an enrollment figure of 64, while the primary outcome entries report 24 observations for social network counseling and 21 for individual counseling. The relationship between these numbers, the analysis population, and any missing follow-up measurements is not reported. Without that information, readers cannot assess whether the posted endpoint summaries represent all randomized participants or a subset.

Baseline arm-level blood-pressure values are not reported, and the record does not describe whether the comparison adjusted for baseline or for the network-size strata. The method used to estimate the confidence interval and p-value is also not specified. The masking label is double, but the masked roles and procedures are not described. These omissions limit evaluation of the analysis and potential sources of bias.

The two listed secondary outcomes have no numerical results in the registry record. The record does not report a multiplicity strategy, missing-data procedures, sensitivity analyses, interim analyses, or a detailed statistical analysis plan. The original sample-size justification is not reported; the available planning illustrations are based on the observed effect and are not the trial’s own design calculation.

The record provides limited context for safety events. It lists serious adverse event counts and top event terms, but does not clarify the denominator or arm attribution for the term percentages, or provide details about timing and relatedness. Further participant characteristics, adherence information, and reasons for any unavailable outcomes are not reported in the registry record.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: TEAMS-BP (The Enhancement of Social Networks to Augment Management of Stroke-Blood Pressure) — NCT05258890.
• Registry record last updated 2025-03-26; status last verified 2025-03.
• Results first posted 2025-03-26.
• 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.

21. Record Summary

TEAMS-BP is a randomized, double-masked, parallel-group trial comparing social network counseling with individual counseling for blood-pressure management after stroke. The registry lists enrollment as 64, a start date of 2022-05-31, a primary completion date of 2024-01-26, and terminated status. The reason for termination is not reported in the registry record.

The primary outcome is mean change in systolic blood pressure from baseline to 3 months. The posted means are -10.82 mmHg for social network counseling and -5.31 mmHg for individual counseling. The unadjusted mean difference is 5.51 mmHg, with a 95% confidence interval from 2.203 to 8.817 and an unadjusted p-value of 0.001. Two secondary outcomes are listed, but their numerical results are not reported in the registry record.

Important details about the analysis population, missing data, adjustment, multiplicity, masking procedures, and the trial’s original sample-size rationale are not reported in the registry record. The primary comparison should therefore be interpreted as a summary of the posted outcome data, with those limitations in view.