The Total Film cover for Shutter Island shares alot of synergy with the poster. There is the use of dark blue to incite fear and danger. Thuse use of red is also prominent again. The magazine has evidently tried to stick to only using red white and blue and also a hint of yellow (the lighthouse and the eye in the avatar image, and the art preview at the top).
This is used to put focus on the idea of danger in the film. The yellow is probably used to portray madness (since the setting is a mental asylum)
The magazine is trying to portray the image of horror and fear that will be prominent in the film .