The IMHS is a nationally representative survey of 4,332 adults (18 years +) carried out simultaneously with the Iraq Family Health Survey (IFHS).An additional weight was used to adjust for differential probability of household selection across strata and for differential probability of within-household selection as a function of number of household adults.The IMHS was administered in the central and southern governorates during August and September, 2006, in Anbar during October and November, 2006, and in the Kurdistan region during February and March, 2007.These strata were made up of three in each of the 17 governorates outside of Baghdad (metropolitan, representing the governorate capital; other urban area outside the capital; and rural area) and five in Baghdad (three parts of the city representing Sadar City, Rusafah side, and Al-Karkh side; all other urban areas in the city; and all rural areas outside the city in the metropolitan area).Both surveys were completed in 2006-7 under the direction of the Iraq Ministry of Health, the Iraq Central Organization for Statistics and Information Technology (COSIT), the Ministry of Health of the Kurdistan region (MoHK), and the Kurdistan Regional Statistics Office (KRSO).The measures of segment size were modified based on this new enumeration and the data weighted to adjust for discrepancies between expected and observed numbers of households.Some segments in the Al-Karkh stratum in Baghdad and in the Anbar and Nineveh governorates were replaced due to security problems.Both the IFHS and IMHS were administered face-to-face in a nationally representative sample of the Iraqi household population.Eighteen such segments (9 pairs) were selected with probabilities proportional to size in each of the 56 population strata.As the sampling frame was based on administrative data, a new household listing was carried out before selecting households in each segment.Iraq was divided into 56 different strata for purposes of selecting this initial sample.Five households were then selected randomly within each segment, and one adult (ages 18+) was selected using Kish tables for interview within each household.Each stratum was divided into block-level sample segments that were paired for purposes of sample selection.These replacement segments were over-sampled in anticipation of low response rates.Finally, a post-stratification weight was applied to the data to match the joint distribution of the sample on age, gender, and geography to the population distribution.The sample for the IMHS was a subset of the block-level sample segments used in the IFHS.The IMHS response rate was 95.2%.