I thınk you can't avoid scam ICO's if it is in your faith 
because they can look legit and after six months past of their ico they can say we are done we can't deliver this product because of this because of that bla bla.. You can protect this situation with blockchain or nothing else. If you are not a risky person you need to go on with BTC LTC and Eth or really good proven altcoins.
Yes there is no sure way to ensure we get a successful ICO project. Because almost all ICOs will provide the best explanation they can. We can only read and speculate for good results. But there are important things that can be a reference, see who the people involved in the project. If these people are very reliable then do it because usually a dev who has a good reputation then he will use various ways to be able to produce a project that ended successfully. because they can look legit and after six months past of their ico they can say we are done we can't deliver this product because of this because of that bla bla.. You can protect this situation with blockchain or nothing else. If you are not a risky person you need to go on with BTC LTC and Eth or really good proven altcoins.