More than one in five hospital patients report having persistent pain, with the condition causing depression and anxiety, a team of researchers have found.The study of 15 health centres in 14 countries found that an average of 22% of patients reported persistent pain lasting six months or longer. The proportion complaining of intermittent pain ranged between 5,5% and 33%. The report, based on World Health Organisation (WHO) interviews with 5 438 patients, primarily in capitals, found the highest rates of pain in Chile, Germany, Brazil and Turkey and the lowest in Nigeria, Japan, Greece and China.