Bilateral actigraphic quantification of upper extremity movement in hemiparetic children with perinatal stroke: a case control study.

The sample size was modest (30 stroke participants), which limited the ability to fully define the utility of the measurements. There was a delay of several months between the collection of standard clinical test scores and the actigraphy data, which may have affected the correlation results. The actigraphy devices could not capture brief, small hand movements due to temporal resolution limits. Actigraphy measures movement counts, not functional use; impaired movement patterns might generate high counts that do not represent useful function. Standard clinical tests themselves are imperfect and may reflect different domains of function than actigraphy.

The study was supported by non-U.S. government funding. The authors declared no competing interests.

Do not assume that actigraphy scores directly measure functional ability. The devices count movement intensity, which can be elevated by non-functional, impaired movement patterns. Additionally, the strongest correlations with clinical tests occurred during sleep and rest, not active play, so these findings do not yet prove actigraphy is a superior measure of daily task performance.