More research with adequate controls required

We were interested to read the article by Tabak and Plummer-D’Amato (2010) entitled “Bilateral movement therapy post-stroke: underlying mechanisms and review”. We agree with their conclusion that future research is required to investigate the optimal characteristics of bilateral training interventions and to identify the individuals most likely to benefit from specific types of bilateral training. However many of the studies cited by Tabak and Plummer-D’Amato as providing strong evidence in support of bilateral training in fact demonstrate the considerable methodological limitations of having no control comparison group (Hesse et al 2003, Whitall et al.2000, McCombe Waller et al. 2004, Stinear and Byblow 2004). Lack of an adequate control comparison renders the studies prone to serious bias and potential overestimation of the effectiveness of bilateral training