The research was carried out at Birmingham, London, Leicester and Manchester schools before and after bans were introduced (PDF). It factored in characteristics such as gender, eligibility for free school meals, special educational needs status and prior educational attainment. "Technological advancements are commonly viewed as increasing productivity," write Louis-Philippe Beland and Richard Murphy. "Modern technology is used in the classroom to engage students and improve performance. There are, however, potential drawbacks as well, as they could lead to distractions."