The Lancet, one of the oldest scientific medical journals in the world, published two peer-reviewed studies on the effect of the 2003 invasion of Iraq and subsequent occupation on the Iraqi mortality rate. The first was published in 2004; the second (by many of the same authors) in 2006. The studies estimate the number of excess deaths caused by the occupation, both direct (combatants plus non-combatants) and indirect (due to increased lawlessness, degraded infrastructure, poor healthcare, etc.).