School performance measures are published annually in England to hold schools
to account and to support parental school choice. This article reviews and
evaluates the Progress 8 secondary school accountability system for
state-funded schools. We assess the statistical strengths and weaknesses of
Progress 8 relating to: choice of pupil outcome attainment measures; potential
adjustments for pupil input attainment and background characteristics;
decisions around which schools and pupils are excluded from the measure;
presentation of Progress 8 to users, choice of statistical model, and
calculation of statistical uncertainty; and issues related to the volatility of
school performance over time, including scope for reporting multi-year
averages. We then discuss challenges for Progress 8 raised by the COVID-19
pandemic. Six simple recommendations follow to improve Progress 8 and school
accountability in England.Comment: 67 pages, 8 figure