evidence: The research, by Professor John Jerrim and Sam Sims, looked at more than 1,800 children from grammar school areas in England and Northern Ireland. It found those from families in the bottom quarter of household incomes in England have less than a 10% chance of attending a grammar school. This compares to around a 40% chance for children in the top quarter of household incomes. [...] The analysis from Jerrim and Sims was based upon the UK's Millennium Cohort Study (MCS). A total of 1,039 children from Northern Ireland and 819 children from grammar school areas in England were tracked from nine months through to age 14. The academics were therefore able to consider how factors such as family income, prior academic achievement, private tutoring and parental attitudes and aspirations were associated with children's chances of attending a grammar school. Other key findings from the study include: [...] - An even stronger association between family income and grammar school attendance was found in Northern Ireland. Children from high-income families were 33 percentage points more likely to attend a grammar school than low-income children of equal academic ability.