Imbalances in the knowledge about infant mental health in rich and poor countries: too little progress in bridging the gap.

The vast majority of infants are born in poor countries, but most of our knowledge about infants and children has emerged from high-income countries. In 2003, M. Tomlinson and L. Swartz conducted a survey of articles on infancy between 1996 and 2001 from major international journals, reporting that a meager 5% of articles emanated from parts of the world other than North America, Europe, or Australasia. In this article, we conducted a similar review of articles on infancy published between 2002 and 2012 to assess whether the status of cross-national research has changed in the subsequent decade. Results indicate that despite slight improvements in research output from the rest of world, only 2.3% of articles published in 11 years included data from low- and middle-income countries--where 90% of the world's infants live. These discrepancies are indicative of the progress still needed to bridge the so-called 10/90 gap (S. Saxena, G. Paraje, P. Sharan, G. Karam, & R. Sadana,) in infant mental health research. Cross-national collaboration is urgently required to ensure expansion of research production in low-resource settings.