But experts note that the real figure will definitely surpass 1 percent as many patients have not been diagnosed because of lack of awareness and knowledge.

"The awareness of OCD in China is very low. Many people have no idea about it though they may live with it for more than 10 years. This is correlated to public education," says Wang Zhen, a psychiatrist and mental health expert from Shanghai Mental Health Center, who has researched OCD for a long time.

Figures from Shanghai Mental Health Center show the number of OCD patients has risen at 20 percent annually in recent years. In 2013, the center had about 1,400 new patients.

The cause of OCD is not fully understood, but main theories believe it may be a result of changes in the balance of some brain chemicals or prompted by some genetic elements that have yet to be identified. Also, some environmental factors are suggested to play a role, but more research is needed to be certain.

Meanwhile, other factors may also increase the risk of developing or triggering OCD, such as family history and some stressful life events, according to Jin Haiyan, a psychiatrist from Shanghai Ruijin Hospital.

If people have experienced some traumatic events or tend to react strongly to stress from work, study or relationships, the risk may also increase. It will trigger the intrusive thoughts, emotional distress characteristic of OCD, Jin says.

People who are concerned that they may have OCD are encouraged to see a doctor as soon as possible because early treatment may help prevent OCD from worsening.

"Generally, OCD is treated through a combination of medication and psychological therapy with about 40 to 60 percent cure rate. We are now developing more personalized treatment plans, which are based on the patient's own condition. This will help improve the cure rate, allowing people to lead a normal life," Wang Zhen says.

Wang says many people with OCD are reluctant to see a doctor or tell anyone else about their symptoms.

"Some patients fear they will be thought as crazy, while some feel ashamed of their symptoms. And as a result, many patients delay their treatment and become depressed, which further worsens their condition," he says.

"More effective ways should be worked out to help people dismiss all doubts."