Prince (1968) found virtually no depression in most Asian and African countries. However, psychologists such as Zhang and Kleinman have found disorders with similar symptoms, but different names. For example, in the 1980s, Zhang found that in China, there was little mention of depression. However, instead, a disorder called Neurasthenia was far more common. When interviewing Neurasthenia patients, Zhang found that their symptoms matched the symptoms of depression by over 80%. While the term "depression" was practically unheard of in China, Neurasthenia could well have been a similar disorder – or the same thing.