Crimewatch

[Joanne]

Does Crimewatch really work or does it just frighten everyone?
I quite like crimewatch and especially the solved programmes, however I think it's said it only shows 1 in 5 cases it features. Why would people be more inclined to call following a tv prgramme rather than call when they have information before it's aired? Or is it that people don't know they've seen anything of importance?