St Augustine's Priory, an all-girls school, was one of only two schools to conform to the 10 criteria set out by independent safe-guarding campaigner Jonathan West.
Sixty schools had been randomly selected for the study, which formed part of research for a BBC radio programme.
Head teacher Sarah Raffray, who was appointed last year, said that she has "come in with a big agenda for change at St Augustine's" and made safeguarding a priority so that it is "embedded in every single thing that we do".
The school had been linked to allegations of sexual abuse at Ealing Abbey and nearby St Benedict's School.