A quitting study planned high power: that is not an effectiveness result

Find the statement in the design section

A power or sample-size paragraph usually explains what the investigators intended the study to detect. Check which outcome and follow-up it concerns. A figure designed for one endpoint cannot be borrowed for every secondary outcome, subgroup, or rare event mentioned elsewhere in the report.

NCI defines power as an anticipated probability conditional on design features, including sample size, endpoint, and test. NCCIH explains that study size can affect uncertainty and interpretation. These sources provide terminology, not an efficacy estimate for vaping support. This article does not recommend a sample size or design a clinical trial.

US National Cancer Institute: Statistical power — NCI Dictionary of Cancer Terms · US National Institutes of Health — NCCIH: How To Make Sense of a Scientific Journal Article: Size of the Study

Keep the assumed difference visible

For a hypothetical example, a protocol states that a study was planned to detect a specified difference between two support approaches at a particular follow-up. That planning statement is conditional on the assumed difference and other inputs. It does not establish that the assumed difference existed or that the study observed it.

If the article supplies a power percentage, do not rewrite it as the chance that a participant will benefit. Nor does the target number of participants prove that every planned participant enrolled or provided usable follow-up information. Identify the actual recruitment and analysis populations in the results before deciding how complete the study was.

Read the outcome even when the plan sounds strong

Look for the observed effect estimate and its confidence interval, alongside the study’s methodological limitations. A large study can estimate a small effect precisely, and design defects can persist despite a large sample. An impressive planned power statement cannot substitute for the result or establish that the effect is useful to an individual.

If the study recruited fewer people than planned or changed an assumption, check the authors’ explanation. Avoid calculating a retrospective success probability from the observed effect yourself. If the implications are unclear, ask a statistical question about the actual estimate and uncertainty instead of declaring the study proven or worthless from one planning number.

Use separate sentences for plan and finding

Your reading note can say: “The study was planned for this outcome under these assumptions; it actually reported this estimate with this uncertainty.” Keeping those sentences separate prevents a promotional summary from presenting an intended design capability as a demonstrated quitting benefit.

For individual treatment choices, ask an appropriate professional about the full evidence. This introductory distinction does not certify the trial, assess every assumption, or forecast your result. You can continue arranging practical support while the study remains uncertain. A personal tracking record cannot supply the randomized comparison or sample-size assumptions of a research trial.