What is the most dangerous neighborhood in London? Safest?

Brixton and Stepney are considered dangerous. However, I was robbed in Knightsbridge and so I don't think it's very safe. There are a lot of tourists there which make it a pickpocket/mugging destination. Same for Piccadilly, Leicester Square, Covent Garden. With the opening of borders after the EU there has been an enormous influx of Eastern European criminals both petty and more organised, so keep a sharp eye on your belongings.