The 10/90 divide in mental health research: trends over a 10-year period.

A search (precision value 94%, recall value 93%) of the ISI Web of Science database (1992-2001) revealed that mental health publications accounted for 3-4% of the health literature. A 10/90 divide in internationally accessible mental health literature was evident and remained undiminished through 10 years as low- and middle-income countries (n=152) contributed only 6%, high-income countries (n=54) 94%, and 14 leading high-income countries (with more than 1% contribution for majority of years under consideration) contributed 90% of internationally accessible mental health research. Steps should be taken to improve the research infrastructure and capacity to conduct and disseminate mental health research in general, and on a priority basis in low- and middle-income countries.