Telephone Tinnitus Education for Patients With Traumatic Brain Injury (TBI): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Telephone Tinnitus Education for Patients With Traumatic Brain Injury (TBI) (NCT01129141), a randomized na study. The primary outcome is Tinnitus Functional Index.

2. Clinical Question

The trial was randomized, with a parallel-group design and no masking. Its enrollment was 205. These design features establish the broad framework for interpreting the comparison, but they do not supply the missing outcome estimates. In particular, the registry record does not report a single effect estimate, confidence interval, or test result for the primary outcome. The posted tables and plots may display calculated summaries, but the interpretation of those displays must remain distinct from a sponsor-reported analysis when the registry does not present that analysis.

3. Trial Design

This was a randomized, parallel-group trial with no masking. The registry lists enrollment of 205 and describes two procedures: Tele-PTM and Wait List Control. The study status is completed. The record lists a start date of 2011-01 and a primary completion date of 2015-09. The sponsor was the VA Office of Research and Development. The registry does not report the method used to generate or conceal the random allocation sequence, or whether allocation was stratified.

Tele-PTM adapted Progressive Tinnitus Management for delivery by telephone. The intervention description specifies seven appointments at approximately 1, 2, 3, 4, and 5 weeks, and 3 and 6 months after enrollment was finalized. It is described as a home-based program. The record does not report how much of the planned program participants completed, whether appointments could be rescheduled, or how adherence was measured.

Participants assigned to the wait-list group were told they could access available tinnitus services. The record says they would receive Tele-PTM after completing questionnaires at 3 and 6 months; it also describes receipt after completion of the 6-month questionnaires. This supports the broad characterization of a delayed-intervention comparison, but the details of any services used during the waiting period are not reported in the registry record.

The primary measure is named as the Tinnitus Functional Index, with a timeframe of baseline and 6 months. Although the registry lists one primary outcome measure, its skip note indicates that the outcome has several categories or time points and has not been reduced to one comparison. Accordingly, this page cannot describe a single registry-reported endpoint contrast. Details such as the planned statistical model, the principal analysis population, handling of missing scores, and any covariate adjustment are not reported in the registry record. The trial’s design description alone does not establish how those analytic choices were made.

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: Candidates must have had a hearing test within the previous 2 years. They were required to get hearing aids if recommended and wear them for at least 1 month before entering the study. Consented candidates were assessed for phone counseling suitability. If current suicidal ideation (SI) was expressed, the subject was excluded from the study.

Overall Study

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Tinnitus Functional Index, measured over Baseline, 6 months.

The primary endpoint is the Tinnitus Functional Index (TFI), a 25-item self-report questionnaire described in the registry as measuring the severity and negative impact of tinnitus. The registry says the measure has documented validity for assessing tinnitus severity and impact, as well as responsiveness to treatment-related change. Its total score ranges from 0 to 100, with higher scores indicating greater problems with tinnitus.

The TFI was selected as the primary outcome measure in this trial because it addresses the experience the telephone-based program was intended to manage. A repeated measure at baseline and 6 months can describe scores at the start and later in follow-up. However, those time points alone do not specify the exact estimand: a reported analysis could compare follow-up scores, changes from baseline, or a model using measurements over time. The registry record does not say which approach was used or report one reduced comparison.

The registry describes excellent internal consistency, with Cronbach's α = .97, and high test-retest reliability, with r = .86. It also reports that the authors of the TFI estimated that a 13-point decrease for an individual is likely to reflect a change that feels meaningful to that person. That individual-level interpretation should not be treated as a trial result or as a threshold automatically applicable to a difference between group averages. No group-level outcome estimate is reported.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What randomization contributes. Random allocation is intended to make the assigned groups comparable, on average, with respect to characteristics that might influence outcomes. This is a general statistical purpose of randomization, not evidence that every characteristic was balanced in this trial. The registry identifies the study as randomized, but does not report the sequence-generation or allocation-concealment procedures. It also does not report a baseline table that would permit a detailed review of group comparability.

What a parallel-group comparison represents. In a parallel design, participants are assigned to one group and followed under that assignment. Here the groups were Tele-PTM and Wait List Control. A primary analysis might compare TFI scores at follow-up, compare change from baseline, or use a model that incorporates repeated measurements. These are general analytic options; the registry record does not report which one was used. Because the outcome is described at baseline and 6 months and is not reduced to one comparison, the precise target of the reported analysis cannot be identified from the registry.

How to read a confidence interval. In general, a confidence interval communicates the uncertainty around an estimated effect. A relatively narrow interval indicates greater precision than a wide interval, while the interval’s position in relation to a no-difference value helps readers assess which effects are compatible with the data under the model. The registry record does not report a confidence interval for a single primary-outcome comparison, so precision cannot be assessed from that record. A p-value, if reported, would address a different question and would not show the magnitude or practical importance of an effect.

Why standard deviations matter. The primary outcome is continuous, and the registry describes its measure as a mean with standard deviation. In general, the mean summarizes the group’s average score and the standard deviation describes variation among individual scores. Variation is relevant to the uncertainty of a group comparison: larger variation can make an estimated difference less precise when other factors are held constant. The record does not provide a single reduced outcome comparison, so this page cannot explain a trial-reported estimate using those summaries.

Baseline and follow-up scores. When a continuous measure is recorded at baseline and follow-up, analysts may account for baseline values in different ways. Comparing follow-up scores with baseline adjustment can differ from comparing individual changes, particularly when baseline values and follow-up values are related. This is a general methodological point, not a claim about the analysis used. The registry does not report whether the primary analysis adjusted for baseline TFI, analyzed changes, or modeled measurements across time.

Repeated measures and within-person correlation. Measurements from the same participant are generally related rather than independent. General methods for repeated measures account for this relationship in different ways. A valid analysis must also make clear which measurements and participants contributed to the estimate. The registry provides the baseline and 6-month timeframe but does not report a repeated-measures model, covariance structure, or analysis population. Without those details, the registry description is insufficient to reconstruct the primary analysis.

Over-dispersion and model assumptions. Over-dispersion is a general concern when observed variability exceeds what a model assumes. It is often discussed for count outcomes, where extra variability can make standard errors too small if ignored. The primary outcome is a continuous score, not a count, and no evidence of over-dispersion is reported in the registry record. More broadly, every analysis depends on assumptions about the outcome distribution and model structure; those assumptions and their assessment are not reported.

Multiplicity. Testing multiple outcomes, time points, or contrasts can increase the chance of a chance finding if results are interpreted without accounting for the number of tests. This is a general statistical concern, not evidence that the investigators performed multiple tests. The registry lists one primary outcome measure but flags that it includes several categories or time points and was not reduced to one comparison. The analysis plan for handling multiplicity is not reported in the registry record.

Sample-size illustrations. The sample-size section accompanying this page is a planning illustration based on an observed effect, with equal allocation, a two-sided significance level of 0.05, and a normal approximation. It is not the trial’s own design justification and is not observed power. Its values describe hypothetical planning under the stated assumptions, not what the study was designed to detect or the probability that the trial found an effect. The registry does not report the trial’s sample-size justification or its assumptions.

Recalculated summaries. A recalculated result is an unadjusted calculation from posted summary statistics, not the sponsor’s analysis. It can help readers understand what follows from those summaries but may not match an analysis that adjusts for baseline, accounts for missing data, or uses another model. If there is a discrepancy, the sponsor’s own analysis takes precedence. In this case, the registry record does not report a single reduced primary comparison against which to make a comprehensive assessment of the analysis.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists one primary outcome measure, the TFI, with a timeframe of baseline and 6 months. Its note says the primary outcome has several categories or time points and was not reduced to one comparison. This makes it difficult to identify a single primary contrast from the registry record. The record does not describe whether the investigators treated the time points as separate tests, used a joint model, selected one time point for the principal contrast, or applied any multiplicity adjustment. None of those procedures should be assumed.

Missing outcome data can affect an estimate if the participants with observed follow-up scores differ systematically from those without them. General approaches include analyses based on available observations, imputation, and models that rely on assumptions about why data are missing. Different assumptions can lead to different interpretations. The registry does not report the number of participants with TFI data at each time point, reasons for missingness, an imputation procedure, or sensitivity analyses. The enrollment total and safety denominators do not establish how many participants contributed to the primary outcome analysis.

The registry record also does not identify the primary analysis population, such as whether all randomized participants were analyzed as assigned or whether exclusions were made. It does not report a protocol-defined analysis set or the handling of participants who did not complete the intervention. These details are important for understanding whether the analysis preserves the randomized comparison and how broadly the result applies. Because the record does not report a single reduced outcome result, this page cannot determine how multiplicity or missingness affected a treatment-effect estimate.

11. Safety Results

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

Other (non-serious) adverse events

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

The registry lists serious adverse events for 0 of 101 participants in the Tele-PTM group and 0 of 104 participants in the Wait List Control group. It also lists other adverse events for 0 of 101 and 0 of 104 participants, respectively. These are the event counts and at-risk denominators displayed in the record; they are not a measure of the TFI outcome.

Zero events in the posted counts means that no events in those categories are listed for these groups in this registry entry. It does not establish that no adverse experiences occurred, that the intervention has no risks, or that the two groups are equivalent in safety. The record does not report the event-collection timeframe, definitions, ascertainment procedures, or a statistical comparison of adverse events. Death counts are not reported in the registry record. The registry also lists no serious adverse event terms. Readers should interpret these figures as the specific event reporting shown, rather than as a comprehensive assessment of safety.

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

This trial record describes a randomized evaluation of Tele-PTM, a telephone-based adaptation of Progressive Tinnitus Management, compared with a wait-list control. It identifies people with tinnitus who have experienced TBI as the population of interest and the TFI as the primary outcome. These details explain the intervention, comparison, and measure that frame the research question.

The record does not provide a single reduced comparison for the TFI across baseline and 6 months. It therefore does not show the magnitude or direction of a between-group result, its precision, or whether a statistical test found evidence of a difference. The record cannot be used to claim that Tele-PTM improved TFI scores, that it did not, or that the groups were equivalent. An unreported result is not the same as a result of no effect.

The TFI description offers context for understanding the measure: it is a self-report scale whose higher scores indicate greater tinnitus problems, and the registry describes a 13-point decrease for an individual as likely to feel meaningful to that person. This is background about interpretation of the instrument, not evidence that a change of that size occurred in the trial. Nor does an individual-level interpretation automatically establish the meaning of a difference between group averages.

The design and implementation details also set boundaries on what can be inferred. The study was randomized and had no masking, but the registry does not report allocation procedures, adherence, outcome missingness, or the primary analysis model. The intervention schedule and wait-list arrangements are described, though the registry gives slightly different wording about when control participants received Tele-PTM. These limitations leave important questions about the actual analysis and exposure unanswered.

The most defensible reading is that the registry documents the trial’s structure and its intended outcome assessment, but does not report enough outcome analysis to determine the comparative result. The posted displays may offer additional summaries, but they should not be mistaken for an unreported sponsor analysis. Any planning illustration is hypothetical and should not be interpreted as observed power or as proof that the study could or could not detect an effect.

13. Why This Trial Matters Statistically

This trial is statistically notable for pairing a randomized parallel-group design with a patient-reported continuous outcome. Such a design can support a comparative assessment when the outcome, time point, analysis population, and statistical method are clearly specified. Here, the registry names the TFI and gives baseline and 6-month assessment times, but does not reduce those measurements to one primary contrast. That gap illustrates why a registered endpoint description is not the same as a report of an interpretable effect estimate.

The TFI also illustrates the distinction between measurement properties and trial findings. The registry describes validity, reliability, and an individual-level interpretation of a 13-point decrease. These details help explain why the instrument may be useful, but they cannot substitute for group means, variability, a treatment contrast, or an uncertainty interval. Statistical interpretation requires both an outcome measure and a reported analysis of the trial data.

The study’s open-label design is another important context for a self-report outcome. Participants and providers were not masked, according to the registry. This fact does not determine the direction or size of any bias, and it does not invalidate the outcome. It does mean that expectations and knowledge of assignment may be relevant considerations when interpreting reported self-reported outcomes. The registry does not describe procedures intended to address those considerations.

Finally, the record demonstrates why reporting of missing data, analysis populations, and multiplicity matters. Without those details and a single primary comparison, readers cannot fully assess precision, robustness, or how the analysis maps to the original question. The trial design is informative, but a transparent statistical result is needed before readers can judge what the observed data indicate.

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.

A central limitation of the registry entry is that it does not provide a single reduced primary-outcome comparison. The TFI is listed with baseline and 6-month time points, and the record explicitly notes that the outcome has several categories or time points. Without a reported contrast, estimate, and uncertainty measure, the comparative result cannot be interpreted from the registry record alone.

The entry does not report the primary analysis method, adjustment for baseline scores, analysis population, handling of missing data, or multiplicity procedure. It also does not give the number of participants with observed TFI scores at each assessment. These omissions limit assessment of whether the analysis corresponds to the randomized comparison and how sensitive it may be to incomplete follow-up or analytic choices.

The study had no masking, and the primary outcome was self-reported. Those features are relevant context when considering possible influence of expectations or awareness of assignment. They do not establish that bias occurred or indicate its direction. The registry does not report an approach for minimizing or evaluating these potential influences.

The arm descriptions differ slightly in their wording about when wait-list participants received Tele-PTM: one description refers to completing the 3- and 6-month questionnaires, while another refers to completing the 6-month questionnaires. This leaves the precise timing less clear in the registry. The entry also does not report details of intervention adherence, use of other tinnitus services, or the complete eligibility criteria. Finally, safety event definitions and collection timeframe are not reported, and death counts are not reported in the registry record. These are reporting limits, not proof that the procedures or data were absent from the study itself.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Telephone Tinnitus Education for Patients With Traumatic Brain Injury (TBI) — NCT01129141.
• Registry record last updated 2017-01-26; status last verified 2016-11.
• Results first posted 2016-11-23.
• 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 describes a completed randomized, parallel-group trial with no masking, enrollment of 205, and two assigned groups: Tele-PTM and Wait List Control. The intervention was a telephone-based adaptation of Progressive Tinnitus Management with seven planned appointments. The primary outcome was the Tinnitus Functional Index, recorded at baseline and 6 months.

The registry does not report a single reduced primary-outcome comparison, its statistical method, or an effect estimate and uncertainty interval. It also does not report the primary analysis population or handling of missing outcome data. Safety reporting lists 0 serious and 0 other adverse events in each group; death counts are not reported in the registry record. The available information supports a description of the trial’s design and outcome measure, but not a conclusion about the comparative TFI result.