Even with glazed doors, a lot of different factors contribute to how secure the doors are. Things you should look at include:
Locks
One incredibly important factor is the locking system on your door. Current building regulations highlight the minimum level of security a door should provide, but you should always look for a five-lever mortice deadlock. These are a lot more secure than a simple cylinder lock.
Cylinder locks are commonly used in uPVC doors but are generally considered a security risk as the lock can easily be snapped off. If this does happen, the lock is left useless and will not stop anyone from entering your property. A mortice lock is a lot more secure as it makes multiple points of connection.
Door Frame
Another important step to having a secure door is having a strong, secure door frame. This is not something homeowners necessarily consider when weighing up the security of their home, but it can be as important as the door itself, particularly wooden ones.
You should regularly inspect your door frame to check for any damage or weak spots. You can also install a reinforcer which will add extra support to your frame against impact.
Hinges
External doors should be hung with their hinges on the inside of your home as standard. You should also make sure your hinges use screws that are at least 2 1/2 inches long. These will help anchor the hinge to the door better, helping it hold up to impact
You can also install hinge bolts as a further way of reinforcing your hinges.