This study demonstrated that training on a tablet, for on average 19 hours across 20 weeks, improved basic arithmetic skills after training in the math conditions compared to control / placebo conditions. The effects were medium sized at post assessment. There was a fadeout of effects at 6 months follow-up, where small effects were shown, and the effects decreased further at 12 months follow-up.
Children with lower non-verbal IQ seemed to gain significantly more at follow- ups than children with higher non-verbal IQ. Furthermore, persistent long-term effects were found for children with lower non-verbal IQ were found. Similar patterns, although not significant, were demonstrated for children with low socioeconomic status and children attending schools with high levels of diversity.
The study found no additional effects of combining working memory training and math training.