The objective of the present study was to examine the short-term effectiveness of a 11-week chess training course for children with ADHD. This is a naturalistic, descriptive clinical intervention study.

Sample and procedure: Parents of 44 children between 6 and 17 of age with a primary diagnosis of ADHD consented to take part into the present study. Parents completed the Spanish version of the Swanson, Nolan and Pelham Scale for parents (SNAP-IV) and the the Abbreviated Conners Rating Scales for parents (CPRS-HI) prior to 11-week chess training course. Statistical Analyses: We used a paired t test statistic to compare pre- to post- intervention outcomes, and Cohen-d calculations to measure the magnitude of the effect. Statistical significance was set at p< 0.05.

After 11 weeks of these pilot programme, more than 80% of children showed improvement in the severity of ADHD. T-test revealed that children with ADHD improved in both the SNAP-IV (t=6.23; d.f.=41; p< 0.001) and the CPRS-HI (5.39; d.f.=33; p< 0.001). Our results suggest a large effect in decreasing the severity of ADHD as measured by the SNAP-IV (d=0.96) and the CPRS-HI (d=0.92)