I believe it says ("self-reported integrity") that when asked to assess your own integrity, that women generally claim to have a higher standard of integrity than men.
The assesment question probably wouldn't be a direct, "How much integrity do you feel you have?" - it would be more like, "You've just found some money lying loose on a park bench. Would you report it to the police or try to find the owner if it were $1? $10? $1000? $10,000?" - and a woman might be more eager to say she would call the cops for a lower amount, for example.