The diagnosis of anxiety disorder is purely clinical. The examining doctor will take a detailed history of symptoms and try to clasify them. A detailed classification is required as there are many causes and different presentation of anxiety disorders. The presenting complaints of the patient may be mixed and needs to be sorted out before coming to the diagnosis.
Once the diagnosis of anxiety is made and classified into certain category of anxiety disorder the next step is to rule out the probable diseases that are known to cause anxiety. (refer the causes for clear understanding)
Due to its complex nature a detailed history of present and past medication, dietary habits, emotional stress, work and family life, family history, etc. will be taken.
Blood investigations can be done to rule out causative diseases like diabetes, thyroid disorders, etc. There is no specific test which can diagnose anxiety as earlier said it is diagnosed on clinical grounds.
There are few methods to schedule an interview with the patient in order to judge the level of anxiety.