"In many geographic regions, both in developing and in developed countries, the number of health workers is insufficient to acheive population health goals. Financial incentives for return for service are intended to alleviate health worker shortages; A (future) health worker enters into a contract to work for a number of years in an underserved area in exchange for a financial pay-off...We carried out systematic literature searches..for studies evaluating outcomes of financial incentive programs published up to February 2009." (excerpts from Abstract)