The Notameter is an ICAO research tool that takes a look at NOTAM Quality.

Weʼve set criteria – like the length of the NOTAM, timeframe, format, Q-codes -and use these criteria for a simple pass/fail. A NOTAM Quality score can therefore be seen for country, showing the percentage of satifactory Notams (all criteria met). The scores are updated every 4 hours.

UK is currently scoring a 31.72% NOTAM satisfaction rating:-

More details about NOTAMETER and the criteria it uses are available here: