Dear Daniel 

Comparisons of the proportion of good and outstanding schools over time 

Thank you for your letter on 18 April regarding the comparison of the proportion of good and outstanding schools over time by the Department for Education (DfE). You raised several points about the comparison between 2023 and 2010, and whether this should be considered misleading.  

We agree that there are a number of factors that have likely influenced the number of good and outstanding schools over time. These include changes made to the inspection frameworks as outlined in your letter, as well as other factors such as the impact of Covid-19 and the exemption of outstanding schools from inspections between 2012 and 2020.  

It is our view that the proportion of good and outstanding schools can be a useful indicator of school performance over time. However, as with any high-level comparison, the nuanced nature of any changes may not be fully reflected when used across an extended timeseries. 

We have reviewed the information provided in Ofsted’s methodology information for state-funded schools inspections and outcomes. This document notes that “The overall effectiveness judgement has remained broadly comparable across the different frameworks since 2005” but also that “A range of factors affect both how and when we inspect and limit the comparability of inspection outcomes over time”. It is our view that these messages could appear to be conflicting to users. 

We welcome the updated line Ofsted has now published in the methodology information and hope that this will support future communications of these figures when comparisons are made over long periods. If you have any additional concerns or if you would like to discuss this matter further, then please contact us.  

Yours sincerely  


Ed Humpherson
Director General, OSR