Background: There were an estimated 35.6million people with dementia in 2010, the numbers nearly doubling every 20years, with an expected 65.7million in 2030 and 115.4million in 2050. 58% of all people with dementia worldwide live in low and middle income countries, rising to 71% by 2050 (Alzheimer’s World Report, 2009).

Objectives: This study sets out to assess the international distribution of both included and excluded studies within published Cochrane Dementia and Cognitive Improvement Group (CDCIG) intervention reviews.

Methods: Over 100 reviews are to be assessed for this study. The following information will be extracted from each • the country of origin of both included and excluded • the country or countries of recruitment of participants from included and excluded studies • the absolute number of participants from each included and excluded study • the main diagnostic criteria used for each included study.Results: The final data collection for this study will be in July 2011. It is expected that less than 10% of included Cochrane dementia studies will be from low and middle income countries yet this is where proportionate increases in the number of people with dementia will be much steeper compared with high income countries.