This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for PDA+: A Personal Digital Assistant for Obesity Treatment (NCT00371462), a randomized na study. The primary outcome is Weight (Measured at Assessment Visits) and Pain Intensity and Pain Related Disability (NRS-I).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00371462 |
| Phase | NA |
| Condition | Obesity, Pain |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 70 |
| Arms in the primary outcome | n/a |
| Lead sponsor | VA Office of Research and Development |
| Results posted | Yes |
2. Clinical Question
Population
People with obesity and chronic pain, as described in the study summary. The registry record does not report further eligibility details or a demographic profile of participants.
Intervention
MOVE! level 2 group weight-loss counseling plus a personal digital assistant decision-support tool. The study summary also describes distance support, while the arm description names the decision-support tool; the details of that support are not reported in the registry record.
Comparator
MOVE! level 2 group weight-loss counseling alone, identified as VA standard care.
Primary question
Whether adding the PDA-based support to standard care would improve weight outcomes and reduce pain intensity and pain-related disability compared with standard care alone.
The study summary frames the primary hypotheses around weight loss at 6 months, maintenance of weight loss at 12 months, and changes in pain intensity and pain-related disability. It also lists secondary questions about quality of life, treatment adherence, and care utilization. These are planned research questions, not findings: the registry record says the study was terminated by VA and that no data were analyzed due to termination.
In general, a randomized comparison is intended to assess whether outcomes differ between assigned groups while reducing the influence of baseline differences. That design intent does not establish that groups were enrolled, followed, or analyzed as planned. The registry record does not provide outcome estimates or a comparison of the assigned strategies, so it cannot answer whether the added PDA support changed weight or pain outcomes.
3. Trial Design
The registry describes a randomized, parallel-group study with no masking. Enrollment is listed as 70. The sponsor is the VA Office of Research and Development. The study began in 2007-10, had a primary completion date of 2009-09, and is listed as terminated. The phase is recorded as NA.
One arm was MOVE! level 2 group weight-loss counseling alone, described as standard care. The other was MOVE! level 2 counseling plus a personal digital assistant decision-support tool. The intervention list calls this “Use of PDA + support to reduce weight and pain.” The brief summary refers to MOVE2! plus PDA plus support, while the arm description names the PDA tool without further detail. The exact content and delivery of any distance support are not reported in the registry record.
Random allocation means assignment is intended to use a chance-based process; parallel design means the assigned groups are compared over the same general study period rather than crossing participants between strategies. Those are general descriptions of the design labels, not evidence that the intended procedures were completed. The record does not report the randomization sequence, allocation concealment, or operational details of enrollment and follow-up.
The planned assessment schedule for the primary outcome lists baseline and 3, 6, 9, and 12 months. The record does not give a participant flow, the number who actually received each intervention, or the number completing assessments. Although enrollment is listed as 70, it should not be treated as the number randomized, analyzed, or observed at any follow-up time. The record explicitly states that no VA outcome data were available to report and that no data were analyzed because of termination.
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
| Stage | + Mobile | Standard-of-care |
|---|---|---|
| STARTED | 35 | 35 |
| COMPLETED | 27 | 27 |
| NOT COMPLETED | 8 | 8 |
Reasons for not completing this period:
| Reason | + Mobile | Standard-of-care |
|---|---|---|
| Withdrawal by Subject | 1 | 0 |
| Other | 7 | 8 |
Analysis population for the primary outcome, as defined in the registry: No data were analyzed due to termination of the 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.
Population: One subject withdrew from the study.
| Characteristic | Unit | Arm 1 | Arm 2 | Total |
|---|---|---|---|---|
| Participants analysed | 34 | 35 | 69 | |
| Age, Continuous | years | 57.7 (SD 13.5) | 57.7 (SD 10.2) | 57.7 (SD 11.9) |
| Sex: Female, Male: Female | Participants | 5 | 5 | 10 |
| Sex: Female, Male: Male | Participants | 29 | 30 | 59 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 3 | 4 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 33 | 32 | 65 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 9 | 8 | 17 |
| Race (NIH/OMB): White | Participants | 25 | 27 | 52 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | 34 | 35 | 69 |
| Weight (kg) | kg | 113.7 (SD 16.1) | 110.1 (SD 15.1) | 111.1 (SD 15.6) |
| BMI | kg/m2 | 36.9 (SD 5.4) | 35.8 (SD 3.8) | 36.3 (SD 4.6) |
| Waist circumference (cm) | cm | 120.4 (SD 14.0) | 120.4 (SD 8.9) | 120.4 (SD 11.7) |
6. Primary Endpoint
The registry lists the primary outcome as Weight (Measured at Assessment Visits) and Pain Intensity and Pain Related Disability (NRS-I), measured over baseline, 3, 6, 9, and 12 months.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary outcome is described as weight measured at assessment visits and pain intensity and pain-related disability measured using NRS-I. The listed assessment times are baseline and 3, 6, 9, and 12 months. The registry record does not specify a unit, a summary parameter, or a measure of dispersion for this outcome. It also does not clarify exactly how weight and the pain-related measures would be combined or compared for the primary analysis.
Weight is relevant to the stated study question because the study aimed to assess weight loss and its maintenance over follow-up. Pain intensity and pain-related disability address the additional question of whether the intervention was associated with changes in pain experience and its effects on functioning. These are general reasons such measures may be selected; they are not evidence that either outcome changed in this study.
The primary outcome is a planned measure, not a reported result. The registry record says the study was terminated by VA, no VA outcome data were available to report, and no data were analyzed due to termination. Consequently, there are no posted outcome values, between-group estimates, or uncertainty intervals to interpret for weight or pain. Details such as the exact weight summary, the scoring and direction of NRS-I, and the prespecified contrast are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the registry record reports no analyzed outcome data. It records the intended comparison between MOVE! level 2 counseling alone and counseling plus a PDA decision-support tool, but it does not provide an estimate of the difference between those groups for weight, pain intensity, or pain-related disability. The primary outcome description and assessment schedule indicate what the study planned to measure, not what participants experienced.
There is therefore no basis in the posted results for describing the size, direction, or precision of an intervention effect. No outcome estimates, confidence intervals, or p-values are reported in the registry record. A confidence interval, in general, expresses the uncertainty around an estimated quantity under a statistical model; without a reported estimate and interval, the data cannot show whether effects were small, large, or compatible with different possibilities.
The listed enrollment of 70 does not fill this gap. Enrollment is not an outcome, and the registry record does not establish how many people were randomized, received each intervention, completed follow-up, or contributed to an analysis. The adverse-event entries list 34 people at risk in the “+ Mobile” group and 35 in “Standard-of-care,” but those figures are not outcome-analysis denominators and should not be used to infer group completion or the primary analysis population.
The record also lists one outcome measure and zero analyses. It states that no data were analyzed due to termination, and the primary outcome description says there were no VA outcome data to report. The study status is terminated. These statements explain why the record offers no trial-effect estimate; they do not indicate that the intervention had no effect or that the comparison produced equivalent outcomes.
In general, a result that is not reported is different from an estimate near zero. An estimate near zero would still have a numerical value and some level of precision. Here, there is no posted estimate to evaluate. Similarly, the absence of reported adverse events in the registry entries should be read as a limitation of the available safety reporting, not as proof that no adverse events occurred during the study.
The study’s planned questions remain clinically and statistically distinct: weight at 6 months, maintenance at 12 months, and pain outcomes are not interchangeable endpoints. Because no outcome data were analyzed, the record cannot establish results for any of them, nor can it support conclusions about the secondary questions on quality of life, adherence, or care utilization.
9. Statistical Methods Explained
Randomized parallel-group comparison
The study is registered as randomized, with a parallel model and no masking. In general, random allocation is intended to make assignment independent of participant characteristics, so that a comparison between groups can estimate the effect of assignment more fairly than a comparison based on self-selection. A parallel design keeps participants in their assigned group for the study rather than switching them between strategies. These are general properties of the design labels; the registry record does not describe the randomization procedure, concealment, or whether the intended allocation process was completed.
No masking means the study is not described as blinded. In general, awareness of an assigned behavioral intervention can affect participants’ expectations, engagement, reporting, or delivery of care. Masking details for outcome assessors are not reported in the registry record. No claim can be made about the influence of these issues in this study because the record contains no analyzed outcome data.
What would an effect estimate represent?
For a randomized comparison, an effect estimate would quantify the difference between the groups on a defined outcome and at a defined time or across a defined set of times. The stated primary outcome includes measured weight and pain intensity and pain-related disability at baseline, 3, 6, 9, and 12 months. The summary emphasizes weight loss at 6 months, maintenance at 12 months, and pain outcomes. The registry record does not identify a single numerical contrast, define the summary parameter, or give an estimate for any time point.
In general, an estimate is more informative when reported with a measure of uncertainty. A confidence interval describes a range of values compatible with the data and assumptions of the analysis. Its width reflects precision: wider intervals indicate less precision, while narrower intervals indicate more precision. No confidence intervals or other precision measures for study outcomes are reported in the registry record, so neither the magnitude nor precision of a treatment comparison can be assessed.
Why the analysis plan matters
Repeated assessments raise general analysis choices, such as whether to compare groups at each visit, model trajectories over time, or define a particular follow-up contrast as primary. Those choices can lead to different estimands and interpretation. The registry record lists the assessment schedule but does not report the statistical model, covariate adjustments, handling of baseline values, or a prespecified strategy for repeated measurements. Since the record says no data were analyzed, there are no model results to interpret.
In general, a statistical analysis plan also clarifies which participants are included, how deviations from assigned treatment are handled, and how missing measurements are addressed. Those choices matter because estimates can depend on the analysis population and assumptions about unavailable observations. The registry record does not report an analysis population or missing-data method. The stated reason for not reporting results is termination and the absence of analyzed data; the record does not quantify missing observations.
What planning calculations can and cannot say
General sample-size illustrations describe how many participants might be needed under specified assumptions to detect a chosen effect with a chosen error rate and power. They are planning calculations, not evidence about the observed outcomes and not a measure of the probability that a completed study found an effect. The record describes planning assumptions involving a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect expressed as a fraction of an observed effect. It also distinguishes participants per arm from total events for time-to-event calculations. However, no outcome effect was analyzed or reported in this trial. Those general assumptions cannot supply a trial result, and no planning illustration should be interpreted as observed power.
In general, a p-value evaluates how unusual data at least as incompatible with a specified null hypothesis would be under the model assumptions, if that null hypothesis were true. It does not measure the size or clinical importance of an effect. The registry record reports no p-values for the primary outcome. There is therefore no hypothesis-test result to interpret, and no basis for labeling the study positive or negative on statistical significance grounds.
Finally, the record’s zero analyses and statement that no data were analyzed are central to method interpretation. Statistical methods can describe how a valid comparison might be constructed, but methods alone cannot produce evidence about an intervention. Without analyzed outcomes, the registry supports description of the planned design and reporting gap, not an estimate of efficacy or a conclusion about the relative outcomes of the groups.
10. Multiplicity, Missing Data and Analysis Populations
The study summary lists several primary hypotheses: weight loss by 6 months, maintenance of weight loss at 12 months, and reduction in pain intensity and pain-related disability. It also lists secondary hypotheses involving quality of life, treatment adherence, and care utilization. Multiple outcomes and assessment times can create multiplicity: in general, testing more than one hypothesis increases the chance of at least one apparently notable result arising by chance when all null hypotheses are true. Statistical plans may address this by defining a primary contrast, ordering tests, or adjusting interpretation, but the registry record does not report a multiplicity strategy.
Because no data were analyzed, the record contains no test results across which multiplicity could be evaluated. It also does not identify a hierarchy among the stated primary hypotheses or specify how the repeated assessments would contribute to a single primary analysis. These details are not reported in the registry record.
Missing-data methods are likewise not reported. The assessment schedule spans baseline and 3, 6, 9, and 12 months, but the record does not say how many observations were available at those visits or why measurements might be absent. In general, missing-data assumptions matter because estimates based on incomplete follow-up can depend on why values are missing and on the method used to account for them. Here, the record states that no data were analyzed due to termination, so no missing-data method or sensitivity analysis can be assessed.
The analysis population is not reported in the registry record. It is not possible to determine whether analyses were intended to follow randomized assignment, include only participants who received treatment, or use another definition. The listed enrollment does not establish the analyzed population. These omissions are especially important for interpreting a planned randomized comparison, but they do not change the primary limitation: no outcome analyses or results are reported.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| + Mobile | 0 | 34 | 0.0% |
| Standard-of-care | 0 | 35 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| + Mobile | 0 of 34 |
| Standard-of-care | 0 of 35 |
The adverse-event entries list 34 people at risk in the “+ Mobile” group and 35 in the “Standard-of-care” group. For serious adverse events, the entries report 0 affected in each group. For other adverse events, the entries also report 0 affected in each group. The death counts are recorded as null rather than as a numeric count, so deaths are not reported in the registry record.
These are registry counts, not proof that no events occurred among all study participants. The record does not explain the safety reporting period, event definitions, ascertainment procedures, or whether the at-risk figures represent all enrolled, randomized, treated, or followed participants. The group label “+ Mobile” differs from the treatment arm description, which refers to a PDA decision-support tool; the registry record does not clarify that labeling.
In general, an event count of zero in a reported group means that no affected participants are listed for that entry. It does not establish that an intervention has no safety risks, particularly when the study was terminated and outcome data were not analyzed. The safety figures should therefore be read narrowly as the recorded counts, with the denominator and reporting context unresolved in the registry record.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized, parallel-group study was planned to compare MOVE! level 2 counseling alone with counseling plus a PDA decision-support tool for people with obesity and chronic pain. It also documents the intended weight and pain assessments, the enrollment listing, the sponsor, and the study’s terminated status. These details describe the study question and design.
It does not establish whether the added support changed weight, maintenance of weight loss, pain intensity, or pain-related disability. No VA outcome data were reported, and no data were analyzed due to termination. There is no effect estimate or uncertainty interval from which to judge the direction, magnitude, or precision of a group difference. The absence of an estimate is not evidence that the two approaches had the same outcomes, and it is not evidence that either approach was superior.
The record also cannot answer the listed secondary questions about quality of life, treatment adherence, or care utilization. It does not report participant-level follow-up, analysis populations, or a statistical analysis plan. Accordingly, the planned assessments and hypotheses should not be mistaken for completed analyses or findings.
The serious and other adverse-event entries report zero affected participants in the two listed groups, while deaths are not reported in the registry record. These entries do not provide enough context to conclude that no adverse events occurred during the study or to compare safety reliably. They are a limited record of what was entered, not a complete account of clinical experience.
In general, a terminated study can still contribute useful information about the research question and the obstacles to obtaining an estimate. For this record, however, the statistical conclusion is limited: the planned comparison is documented, but its outcome remains undetermined in the registry record.
13. Why This Trial Matters Statistically
This study matters statistically because it illustrates the distinction between a registered research question and an answer supported by analyzed data. The record specifies a randomized comparison, a population described as having obesity and chronic pain, a behavioral intervention, a standard-care comparator, and repeated planned measurements. Those features define what investigators intended to evaluate. They do not substitute for outcome estimates.
For clinical researchers, the record also highlights the importance of clear endpoint definitions. Weight, pain intensity, and pain-related disability are listed together, and the summary emphasizes several hypotheses across different follow-up times. A statistical analysis plan would ordinarily clarify the target contrast, priority of outcomes, handling of repeated measurements, and approach to multiplicity. Those details are not reported in the registry record, and no analyses were conducted according to the record.
Enrollment alone does not tell readers how much information was available for an outcome analysis. The listed enrollment is 70, while the safety entries list different at-risk counts. Without participant flow and analysis-population details, those figures cannot establish the number of participants contributing to each planned assessment. The record’s termination and lack of analyzed outcome data make this distinction particularly important.
Finally, a lack of results should not be translated into a null effect. Statistical evidence requires an estimate and information about its uncertainty; neither is reported for the primary outcome. The record is therefore informative about the intended design and the limits of the available evidence, but it cannot resolve the comparative effectiveness question it set out to study.
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 principal limitation is explicit: the study was terminated by VA, no VA outcome data were available to report, and no data were analyzed due to termination. As a result, the registry record contains no primary or secondary outcome estimates with which to assess the planned comparisons.
Details needed to evaluate trial conduct are also not reported in the registry record. These include the number actually randomized, participant flow, intervention receipt, follow-up completion, reasons for termination, and the analysis population. The listed enrollment should not be interpreted as a count of participants with usable outcome data.
The primary outcome description combines weight and pain measures but does not specify the summary parameter, unit, dispersion, exact NRS-I scoring, or a single prespecified contrast. Although the record lists assessments at baseline and 3, 6, 9, and 12 months, it does not report the analysis model, adjustment strategy, missing-data handling, or multiplicity plan. The protocol or statistical analysis plan is not reported in the registry record.
The intervention descriptions are not fully aligned: the summary mentions MOVE2! plus PDA plus support, while the arm description identifies MOVE! level 2 counseling plus a PDA decision-support tool. The details of distance support are not reported in the registry record. The “+ Mobile” safety label is not reconciled with the arm description.
Safety reporting is limited because the registry does not define the reporting period or clarify the denominator represented by the at-risk counts. Deaths are not reported in the registry record. These limitations restrict interpretation of both the planned comparison and the adverse-event entries.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: PDA+: A Personal Digital Assistant for Obesity Treatment — NCT00371462.
- Registry record last updated 2016-10-07; status last verified 2016-08.
- Results first posted 2016-10-07.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT00371462, “PDA+: A Personal Digital Assistant for Obesity Treatment,” is recorded as a randomized, unmasked, parallel-group study sponsored by the VA Office of Research and Development. The registry lists enrollment of 70, a start date of 2007-10, a primary completion date of 2009-09, and status as terminated.
The planned comparison was MOVE! level 2 group weight-loss counseling alone versus counseling plus a PDA decision-support tool. Planned primary measures were weight and pain intensity and pain-related disability at baseline and 3, 6, 9, and 12 months. The registry record states that the study was terminated by VA, no VA outcome data were available to report, and no data were analyzed due to termination. It reports zero serious and other adverse-event counts in the listed groups; deaths are not reported in the registry record.