Mim-pong: a serious game for assessment and treatment of the lower limb in hemiparetic stroke patients.

The groups were not randomised. The researchers decided who went where, and the control group ended up with only 8 patients against 16, so the two groups may have differed in ways the study did not measure. Only 24 patients took part. All of them finished, so the per-protocol analysis did not leave anyone out, but a study this size cannot rule out a real difference between the treatments. The paper does not report any blinding. The strength and motor control measurements were taken by the same examiners, and the control group's training was delivered by the researcher, so the people measuring knew who had received what. Fatigue and motivation were not measured, even though motivation is the main reason the authors give for using a game. Patients were only measured before and after the ten weeks, so nothing is known about whether any gains lasted. Average time since stroke was 16.8 months and most participants were in the chronic phase, so these results may not carry over to people in the first weeks or months after a stroke. The game's score is worked out partly from muscle strength, as the authors themselves note, so the strong link between score and strength is not independent evidence that the score captures anything new. The conclusion that the game outperformed conventional therapy rests mainly on improvements within the game group and on the authors' comparison with a clinical-important-change threshold, not on significant differences between the two groups for strength, motor impairment or walking.

The authors declare that there is no conflict of interest. The text supplied does not name a funding source.

Do not read this as proof the game works better than conventional therapy. After ten weeks the two groups did not differ significantly on strength, motor impairment or walking speed; the only significant differences were in motor control, and the study was not randomised, with 16 patients against 8. A strong link between the game's score and leg strength is also partly built in, because the score itself is calculated in part from strength.