Effect of Structured Info and Adapted Exercise in OA: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effect of Structured Info and Adapted Exercise in OA (NCT02022566), a non-randomized na study. The primary outcome is Level of Physical Activity/Sedentary Time.

2. Clinical Question

3. Trial Design

This completed study is described as an observational study with a control group. Its allocation is non-randomized, its masking is listed as none, and its design model is parallel. These features describe how the comparison was organized; they do not make the groups equivalent at baseline. Because treatment assignment was not randomized, differences between participants choosing or entering the program and those in the control group could influence observed differences over time.

The registry lists 317 participants as the enrollment. The sponsor is Lund University. The recorded start is 2009-04, and primary completion is 2014-12. The study status is completed. The phase is listed as NA. The program arm is described as treatment with a supported self-management program for osteoarthritis, while the control arm is described as receiving no intervention.

The study’s stated hypotheses concern change in physical activity after structured information and individually adapted exercise, and whether activity increases more for participants with knee osteoarthritis than for those with hip osteoarthritis. The primary outcome timeframe is baseline, 3 months and 12 months. The record does not report the recruitment process, allocation criteria, group-specific baseline characteristics, or details of follow-up and adherence. It also does not report a randomized design, so the control group should not be interpreted as a like-for-like randomized comparison.

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

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: The intervention group have been a part of a supported self-management of osteoarthritis and the control group were sign to meet a orthopedic doctor because of problems from knee or hip.

6. Primary Endpoint

The registry lists the primary outcome as Level of Physical Activity/Sedentary Time, measured over Baseline, 3 months and 12 months.

The primary outcome is level of physical activity and sedentary time, expressed in minutes and summarized using the median and inter-quartile range. Measurements are scheduled at baseline, 3 months and 12 months. The measure is intended to describe how much time participants spend in activity or sedentary behavior in ordinary life, rather than relying only on a participant’s recollection or rating.

The registry describes use of a GT1M Actigraph, a small uniaxial accelerometer that records vertical acceleration and deceleration. Its output is an activity count, a weighted sum of measured accelerations over a period such as 10 seconds. Participants are instructed to wear it at the waist, attached to a belt over the right hip, from morning until bedtime for seven consecutive days, except during water activities. Sedentary minutes are calculated, and the average number of minutes in one week is used.

General statistical context: accelerometers provide an objective measure of movement during the wear period, but the resulting measure still depends on wearing the device as instructed and on how the recorded activity is processed. The registry record does not report the observed medians, inter-quartile ranges, or changes in this primary outcome.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes the endpoint as a median with inter-quartile range. It does not report an outcome analysis method, a model for repeated measurements, an adjustment strategy, or a confidence interval procedure. The endpoint summary therefore should not be mistaken for a complete statistical analysis plan. The methods that were actually used to compare groups or time points are not reported in the registry record.

What do the median and inter-quartile range describe?

General statistical context: the median is the middle value when observations are ordered. It is less influenced by unusually high or low observations than the arithmetic mean. The inter-quartile range describes the spread of the middle portion of the observed values. Together, the median and inter-quartile range give a compact account of a distribution, but they do not by themselves quantify the uncertainty in a comparison between groups or the uncertainty in change over time.

For accelerometer minutes, distributions may be uneven: some participants may record much more activity than others, and sedentary time may cluster differently across people. A median-based summary can be useful in such circumstances. However, readers need the actual summaries and a clearly specified comparison method to judge whether a group difference is large relative to variation. Those primary outcome values are not reported in the registry record.

Why does the non-randomized design matter?

General statistical context: random allocation helps balance measured and unmeasured characteristics between groups on average. In a non-randomized study, participants may enter groups through processes related to health, motivation, access, or other factors. Those factors can also be related to physical activity. An observed contrast can therefore reflect differences in participant composition as well as any effect associated with the program.

Adjustment for measured characteristics can sometimes address part of this concern, but it cannot automatically remove confounding from unmeasured factors or errors in measurement. The registry record does not report an adjustment model, covariates, or a strategy for handling confounding. It also does not report whether baseline activity or other characteristics were compared across groups. The strength of any adjusted interpretation cannot be assessed from the information recorded.

How should repeated measurements be understood?

General statistical context: measurements from the same person over time are related. A statistical method for repeated measurements should account for this relationship if it estimates change across assessments or compares trajectories. Separate summaries at each assessment can describe the data, but they do not alone establish whether change differs between groups. The registry gives baseline, 3 months and 12 months as time points, but does not report how repeated observations were analyzed, whether all time points were included in a single model, or how incomplete follow-up was treated.

The stated hypothesis involving knee versus hip osteoarthritis raises an additional comparison across condition groups. To interpret such a question, the analysis would need to distinguish changes by condition and by intervention group. The registry does not report the statistical model or the planned contrast for this hypothesis. It is therefore not possible to infer how this question was tested.

What do the planning assumptions mean?

The record describes planning illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. These are assumptions for planning illustrations, not evidence that the study was designed using those assumptions. The registry record does not report the trial’s own sample-size justification, the observed effect value used for the illustrations, or numerical planning counts.

General statistical context: a planning calculation estimates the sample size associated with a chosen target effect and statistical assumptions. It does not measure the probability that a completed study has detected a real effect, and it is not observed power. When an illustration is expressed as participants per arm for 80% power, that is a planning quantity rather than a result about the enrolled participants. The registry record does not report the original design justification or whether any such calculations informed the study.

A two-sided significance level describes a decision threshold for a test that considers departures in either direction. A normal approximation relies on a mathematical approximation to the sampling distribution. Equal allocation is an assumption about the planned group sizes. These general concepts do not show that the analysis actually used a particular test or model. The registry record does not report the inferential procedures, test statistics, p-values, or interval estimates for the primary outcome.

Why can spread affect statistical methods?

General statistical context: when variability is greater than a model assumes, standard errors based on that model can be too small, making uncertainty appear lower than it is. Over-dispersion is one example of a mismatch between observed variability and a model’s assumed variability. A suitable analysis may need to account for that extra variation. The registry describes accelerometer counts and minute-based summaries but does not report a distributional model or diagnostics, so no claim can be made about whether over-dispersion was assessed or relevant to the analysis.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists seven outcome measures and two analyses. It names health-related quality of life, visual analog scale for pain, and the Arthritis Self-efficacy Scale/Pain among the secondary outcomes. The primary outcome is level of physical activity and sedentary time. The record does not report how the two listed analyses relate to the outcomes, which outcomes were included in each analysis, or whether additional comparisons were planned.

Multiplicity arises when several outcomes, time points, subgroups, or contrasts are tested. General statistical context: as the number of statistical tests increases, the chance of at least one apparently noteworthy result can rise if no adjustment or other strategy is used. Whether adjustment is appropriate depends on the analysis objectives and testing plan. The registry record does not report a multiplicity strategy, such as an adjustment procedure, a hierarchy of outcomes, or a prespecified primary contrast. It is not possible to determine how multiple tests were handled.

The record specifies baseline, 3 months and 12 months for the primary outcome, but it does not report how missing accelerometer observations or missing follow-up assessments were handled. The amount and pattern of missing data are not reported in the registry record. It also does not state whether analyses used only participants with complete observations, included available measurements, or used an imputation approach.

The analysis population is not reported in the registry record. The enrollment is listed as 317, but the record does not give the number analyzed for each outcome, assessment, or group. Without those details, readers cannot determine how many participants contributed to a particular estimate or whether exclusions after enrollment could have affected the comparison.

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 adverse-event record lists the supported self-management group with 195 participants at risk and the control group with 69 participants at risk. For both groups, the record lists zero participants with serious adverse events, zero with other adverse events, and zero deaths. These are the safety figures recorded for the groups; they are not evidence about the primary physical-activity outcome.

General statistical context: a zero count means no events were recorded in the specified category among the participants counted as at risk. It does not establish that the underlying event risk is zero, nor does it show how completely events were monitored or reported. The registry record does not provide event terms, further safety definitions, or additional information about ascertainment. No serious-event terms are listed.

The at-risk counts should not be treated as the numbers with complete accelerometer measurements. The registry record does not report whether the safety and outcome populations were identical, or how safety follow-up was conducted. The recorded zero counts are best read as the posted adverse-event figures, without extending them to broader conclusions about safety.

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

The record documents a research question about physical activity and sedentary time after a supported self-management program for osteoarthritis. It identifies the intervention, a no-intervention control group, the non-randomized design, and an accelerometer-based measurement plan at baseline, 3 months and 12 months. Those details allow readers to understand what the study set out to examine.

The record does not report the primary outcome results. It therefore does not show whether physical activity increased, whether sedentary time changed, how large any group difference was, or how uncertain an estimate might be. The hypotheses about an increase after the program and a greater increase in knee than hip osteoarthritis are expectations, not findings in the registry record.

Even if a difference between groups were reported, this design would require cautious interpretation. Because allocation was non-randomized, group differences could reflect pre-existing characteristics or other influences alongside participation in the program. Without reported adjustment methods and group characteristics, the extent to which a comparison could separate those influences is not assessable from the record.

General statistical context: statistical evidence about a difference depends on both the estimate and its uncertainty, while causal interpretation also depends on the study design and potential sources of bias. A completed study status does not fill in missing result estimates. The posted information supports a description of the design and intended measurement, but it does not support a conclusion that the program did or did not change activity.

The safety figures list no serious adverse events, other adverse events, or deaths in either group. Those registry counts describe recorded events; they do not substitute for primary outcome results or resolve the limitations of a non-randomized comparison. The registry record is therefore informative about study structure but insufficient for judging the size, precision, or causal meaning of the primary comparison.

13. Why This Trial Matters Statistically

This study is statistically interesting because its primary outcome is behavior measured outside a clinic using an accelerometer. The protocol describes a week of device wear at baseline and at follow-up, with sedentary minutes calculated from device output. Such an endpoint raises practical questions about compliance with wear instructions, valid measurement days, and how activity counts are converted into minutes. The registry describes the measurement procedure but does not report adherence or data-processing details beyond the stated calculation.

The non-randomized control-group design also makes the interpretation of change especially important. A before-and-after change in the program group alone would not separate change associated with the program from change over time for other reasons. A comparison with a control group can add context, but non-random allocation leaves the possibility of systematic group differences. The registry record does not report methods for addressing those differences.

The planned assessments at baseline, 3 months and 12 months invite questions about both immediate and longer-term patterns. Yet the record does not report the outcome values or the analysis of repeated observations. It also states a hypothesis comparing participants with knee and hip osteoarthritis, which poses a distinct subgroup question that requires a clear analysis approach.

For statistical readers, the record illustrates the difference between a detailed measurement description and a report of statistical findings. The measurement protocol and study hypotheses are stated, but the primary estimates, their uncertainty, missing-data handling, and analysis methods are not reported. The distinction matters: design information can clarify what was intended without showing what the data demonstrated.

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 most important limitation for interpreting the posted record is that primary outcome results are not reported. There are no outcome summaries, group comparisons, estimates of change, or measures of statistical uncertainty in the registry record. Consequently, the intended question cannot be answered from the recorded results.

The observational, non-randomized allocation limits causal interpretation. The registry does not report how participants entered each group, the baseline comparability of the groups, or methods for addressing confounding. The control group received no intervention, but the record does not establish that it represents a comparable counterfactual for participants receiving the program.

The measurement description specifies a GT1M Actigraph, placement over the right hip, wear from morning until bedtime for seven consecutive days, and exclusion of water activities. However, the record does not report device adherence, the proportion of usable measurements, processing rules beyond the stated sedentary-minute calculation, or outcome data completeness. These details would help readers assess how representative the measured week was of participants’ usual activity.

The registry record does not report the statistical analysis plan, model for repeated measures, adjustment for potential confounding, handling of missing data, analysis population, or approach to multiple outcomes and comparisons. It also does not report the original sample-size justification. The enrollment figure alone cannot establish how many participants contributed to each analysis or whether the study had adequate precision for its intended comparisons.

The safety information is limited to counts of participants at risk and recorded event counts. Further event definitions and ascertainment details are not reported in the registry record. These limitations concern the available record and should not be treated as findings about the study’s unreported analyses.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Effect of Structured Info and Adapted Exercise in OA — NCT02022566.
• Registry record last updated 2022-03-03; status last verified 2021-12.
• Results first posted 2022-03-03.
• 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

NCT02022566 is a completed, non-randomized observational study with a control group, sponsored by Lund University. The registry lists 317 participants enrolled, no masking, and a parallel model. The recorded start is 2009-04, and primary completion is 2014-12.

The study evaluates a supported self-management program for osteoarthritis against a no-intervention control group. Its primary outcome is accelerometer-measured physical activity and sedentary time, summarized as median and inter-quartile range at baseline, 3 months and 12 months. The stated hypotheses concern increased activity and a potentially larger increase among participants with knee rather than hip osteoarthritis.

Primary outcome estimates, analysis methods, missing-data handling, and the analysis population are not reported in the registry record. The adverse-event record lists zero serious adverse events, zero other adverse events, and zero deaths in both groups.