Increasing Adherence to Prophylactic Swallowing Exercises During Head and Neck Radiotherapy: The Multicenter, Randomized Controlled PRESTO-Trial.

Adherence was measured differently between groups. In the paper and app groups it depended entirely on what patients recorded themselves, and the authors note some patients may not have wanted to disappoint their therapist by admitting they had not practised, which could mean real adherence was slightly lower than reported. This paper reports adherence only. Everyone did the same exercises for the same four weeks, so it cannot say whether the exercises improved swallowing function, muscle strength or quality of life. The authors say those analyses are planned next. The study was not powered for adherence at all. The sample size was calculated for a different outcome (MASA-C), and the authors state no power calculation was done for adherence. Experience of the app came from only 13 of the 46 patients in the app group, so the ratings of the tablet and app are weak evidence. The app group had more dropouts than the other groups, and about 11% of data was missing and not accounted for in the analysis. Exercises ran for only the first four weeks; the authors say there is no clear guidance on when the exercises should start or how long they should continue, and they do not know whether four weeks is enough to produce a benefit.

The named funder is Kom op tegen Kanker. The app was developed in collaboration with Cyborn, a commercial animation, app and game studio in Antwerp; the paper does not state what role, if any, the company had in designing, running or writing up the study.

Do not conclude from this trial that therapist-supervised exercises improve swallowing. It measured how many repetitions patients completed, not swallowing function, muscle strength or quality of life. Those outcomes were not reported here and the authors say they will be analysed separately.