Mexico’s National Survey of Population Dynamics (known in Spanish as Encuesta Nacional de la Dinámica Demográfica [ENADID]) is funded by the National Council on Population (known in Spanish as Consejo Nacional de Población [CONAPO]) and INEGI. The purpose of ENADID is to provide information about the different components of population dynamics (e.g., fertility, mortality, internal and international migration). INEGI is responsible for questionnaire design, operational planning, survey execution, and data design, while CONAPO (along with a group of academic experts) participates in a conceptual review and validates the results before publication. ENADID was first fielded in 1992, with subsequent cross-sections in 1997, 2006, and 2009. In its origins, ENADID was one of the few national probability-based surveys that had instruments to measure international out- and in-migration.16
The target population of ENADID is the population permanently residing in private homes in Mexico. The sampling frame is INEGI’s National Households Frame 2002, based on cartographic and demographic information from the General Population and Housing Census 2000. Data from each of ENADID’s cross-sections come from samples aimed at reflecting characteristics of the whole country, each of the 31 states and the Federal District, and urban and rural areas (Instituto Nacional de Estadística y Geografía, undated-a, undated-b; Instituto Nacional de Salud Pública, 2008). Each cross-section of the ENADID aims to represent all household members at the time of the survey (including both Mexican- and foreign-born individuals) and all individuals who were members of the household roughly 5 years prior to the survey and who left the household to move to another country during this period, whether they returned to the sampled household or not.17 Sample sizes for the ENADID surveys have ranged between 40,000 and 100,000 households.
ENADID includes questions to measure international out- and in-migration. In the case of in-migration, all of the ENADID cross-sections use the relatively conventional retrospective question asking if people living in the household were living in another state or country 5 years prior to
16 Before 2000, the Mexican Census only measured in-migration; ENOE’s predecessors only occasionally included migration questions; the Survey of Migration at the Northern Border (see next section) had only started in 1993 and was not continuous (and it also had a different scope and use than the ENADID in terms of understanding international migration flows); and more detailed, non-representative surveys like the Mexican Migration Project (MMP) were only starting and had (more) limited coverage and sample sizes.
17 That is, they could remain in the United States or live elsewhere in Mexico, but only those moving abroad during the prior 5 years would be recorded in these questions.