What causes variability in school-level GCSE results year-on-year?

The article focuses on the research published by Office of Qualifications and Examinations Regulation (Ofqual) of Great Britain regarding the pattern of variability in school and college General Certificate of Secondary Education (GCSE) results. It discusses the factors associated and not associated with the variability such as free school meals, deprivation index, and student proportion with English as an additional language. It also mentioned the impact of grade inflation.