Methodology

This page explains Missing Migrants Project’s methodological framework and serves as a guide for those using its data, as well as for actors interested in collaborating with the Project. For this reason, this page provides information on the challenges of collecting data on migrant fatalities and describes the main definitions, sources, and variables used for data collection.

What is included in Missing Migrants Project data?

Missing Migrants Project counts migrants who have died at the external borders of states, or in the process of migration towards an international destination, regardless of their legal status. The Project records only those migrants who die during their journey to a country different from their country of residence.

Missing Migrants Project data include the deaths of migrants who die in transportation accidents, shipwrecks, violent attacks, or due to medical complications during their journeys. It also includes the number of corpses found at border crossings that are categorized as the bodies of migrants, on the basis of belongings and/or the characteristics of the death. For instance, a death of an unidentified person might be included if the decedent is found without any identifying documentation in an area known to be on a migration route. Deaths during migration may also be identified based on the cause of death, especially if is related to trafficking, smuggling, or means of travel such as on top of a train, in the back of a cargo truck, as a stowaway on a plane, in unseaworthy boats, or crossing a border fence. While the location and cause of death can provide strong evidence that an unidentified decedent should be included in Missing Migrants Project data, this should always be evaluated in conjunction with migration history and trends.

What is excluded?

The count excludes deaths that occur in immigration detention facilities or after deportation to a migrant’s homeland, as well as deaths more loosely connected with migrants´ irregular status, such as those resulting from labour exploitation. Migrants who die or go missing after they are established in a new home are also not included in the data, so deaths in refugee camps or housing are excluded. The deaths of internally displaced persons who die within their country of origin are also excluded. There remains a significant gap in knowledge and data on such deaths. Data and knowledge of the risks and vulnerabilities faced by migrants in destination countries, including death, should not be neglected, but rather tracked as a distinct category.

What sources of information are used in the Missing Migrants Project database?

The Missing Migrants Project currently gathers information from diverse sources such as official records – including from coast guards and medical examiners – and other sources such as media reports, NGOs, and surveys and interviews of migrants. In the Mediterranean region, data are relayed from relevant national authorities to IOM field missions, who then share it with the Missing Migrants Project team. Data are also obtained by IOM and other organizations that receive survivors at landing points in Italy and Greece. IOM and UNHCR also regularly coordinate to validate data on missing migrants in the Mediterranean.

Data on the United States/Mexico border are compiled based on data from U.S. county medical examiners, coroners, and sheriff’s offices, as well as media reports for deaths occurring on the Mexican side of the border. In Africa, data are obtained from media and NGOs, including the Regional Mixed Migration Secretariat and the International Red Cross/Red Crescent. The quality of the data source(s) for each incident^[1] is assessed through the ‘Source quality’ variable, which can be viewed by downloading the data.

Across the world, the Missing Migrants Project uses social and traditional media reports to find data, which are then verified by local IOM staff whenever possible. In all cases, new entries are checked against existing records to ensure that no deaths are double-counted. In all regions, Missing Migrants Project data represent a minimum estimate of the number of migrant deaths.

To learn more about data sources, visit the thematic page on migrant deaths and disappearances in the Global Migration Data Portal.

What are the challenges of collecting data on migrant fatalities?

Data on migrant fatalities are challenging to collect for a number of reasons. First, because the majority of deaths are of migrants travelling by irregular means, they often occur in remote areas chosen because of a lack of legal routes. As a result, bodies are not always found quickly, if it all, and deaths may not be systematically reported to authorities. Furthermore, when deaths occur at sea or in other bodies of water, many of the deceased may not be recovered, and without passenger lists, the precise number of missing is unknown. In addition, the involvement of criminal actors, border guards, and others in the process of irregular migration might make survivors fearful of reporting deaths, and some deaths may even be actively covered up.

Data on migrant deaths and disappearances are also challenging to collect as consistent reporting by states on the deaths of non-nationals in transit, or nationals who have died while in transit abroad is very scarce. Few official sources collect and publish data on migrant deaths. Often incidents come to light through media sources, which may have incomplete and infrequent coverage.

Data on missing migrants tend to over-represent parts of the world where there is better media coverage and official reporting of deaths, such as Europe and the Mediterranean. Comparatively few data on migrant deaths are recorded in areas of the world with large volumes of irregular migration, despite the many dangers migrants face in these regions. For example, some experts believe that more migrants die while crossing the Sahara Desert than in the Mediterranean Sea.^[2]

In order to overcome these challenges, the Missing Migrants Project aims to strengthen existing data sources and partnerships with relevant state and humanitarian agencies in order to address data gaps in six key regions – the Middle East, North Africa, Sub-Saharan Africa, South Asia, Southeast Asia, and Latin America, where there is little information on the risks faced during migration. These regions have been identified by IOM staff as areas of concern since they have high levels of migration but little or no systematic collection of data on the dangers migrants face during their journeys at the national or regional level. Better data collection in these regions could lead to an improved understanding of the conditions migrants face before reaching more visible routes. Improved data will also allow for a more robust regional comparison, and will bring to light the differences and similarities in the challenges individuals face when migrating on various routes. More importantly, the aim of IOM’s Missing Migrants Project is to raise awareness of these challenges and risks, and ultimately, for migration to be safe for all.

What are the variables used in the Missing Migrants Project database?

This section presents the list of variables that constitute the Missing Migrants Project database. While ideally, all incidents recorded would include entries for each of these variables, the challenges described above mean that this is not always possible. The minimum information necessary to register an incident is the date of the incident, the number of dead and/or the number of missing, and the location of death. If the information is unavailable, the cell is left blank or “unknown” is recorded, as indicated in the table below.

Variable Name	Description
Web ID	An automatically generated number used to identify each unique entry in the dataset.
Region of incident	The region in which an incident took place. For more about regional classifications used in the dataset, click here.
Reported date	Estimated date of death. In cases where the exact date of death is not known, this variable indicates the date in which the body or bodies were found. In cases where data are drawn from surviving migrants, witnesses or other interviews, this variable is entered as the date of the death as reported by the interviewee. At a minimum, the month and the year of death is recorded. In some cases, official statistics are not disaggregated by the incident, meaning that data is reported as a total number of deaths occurring during a certain time period. In such cases the entry is marked as a “cumulative total,” and the latest date of the range is recorded, with the full dates recorded in the comments.
Reported year	The year in which the incident occurred.
Reported month	The month in which the incident occurred.
Number dead	The total number of people confirmed dead in one incident, i.e. the number of bodies recovered. If migrants are missing and presumed dead, such as in cases of shipwrecks, leave blank.
Number missing	The total number of those who are missing and are thus assumed to be dead. This variable is generally recorded in incidents involving shipwrecks. The number of missing is calculated by subtracting the number of bodies recovered from a shipwreck and the number of survivors from the total number of migrants reported to have been on the boat. This number may be reported by surviving migrants or witnesses. If no missing persons are reported, it is left blank.
Total dead and missing	The sum of the ‘number dead’ and ‘number missing’ variables.
Number of survivors	The number of migrants that survived the incident, if known. The age, gender, and country of origin of survivors are recorded in the ‘Comments’ variable if known. If unknown, it is left blank.
Number of females	Indicates the number of females found dead or missing. If unknown, it is left blank. This gender identification is based on a third-party interpretation of the victim's gender from information available in official documents, autopsy reports, witness testimonies, and/or media reports.
Number of males	Indicates the number of males found dead or missing. If unknown, it is left blank. This gender identification is based on a third-party interpretation of the victim's gender from information available in official documents, autopsy reports, witness testimonies, and/or media reports.
Number of children	Indicates the number of individuals under the age of 18 found dead or missing. If unknown, it is left blank.
Age	The age of the decedent(s). Occasionally, an estimated age range is recorded. If unknown, it is left blank.
Country of origin	Country of birth of the decedent. If unknown, the entry will be marked “unknown”.
Region of origin	Region of origin of the decedent(s). In some incidents, region of origin may be marked as “Presumed” or “(P)” if migrants travelling through that location are known to hail from a certain region. If unknown, the entry will be marked “unknown”.
Cause of death	The determination of conditions resulting in the migrant's death i.e. the circumstances of the event that produced the fatal injury. If unknown, the reason why is included where possible. For example, “Unknown – skeletal remains only”, is used in cases in which only the skeleton of the decedent was found.
Location description	Place where the death(s) occurred or where the body or bodies were found. Nearby towns or cities or borders are included where possible. When incidents are reported in an unspecified location, this will be noted.
Location coordinates	Place where the death(s) occurred or where the body or bodies were found. In many regions, most notably the Mediterranean, geographic coordinates are estimated as precise locations are not often known. The location description should always be checked against the location coordinates.
Migration route	Name of the migrant route on which incident occurred, if known. If unknown, it is left blank.
UNSD geographical grouping	Geographical region in which the incident took place, as designated by the United Nations Statistics Division (UNSD) geoscheme. For more about regional classifications used in the dataset, click here.
Information source	Name of source of information for each incident. Multiple sources may be listed.
Link	Links to original reports of migrant deaths / disappearances if available. Multiple links may be listed.
Source quality	Incidents are ranked on a scale from 1-5 based on the source(s) of information available. Incidents ranked as level 1 are based on information from only one media source. Incidents ranked as level 2 are based on information from uncorroborated eyewitness accounts or data from survey respondents. Incidents ranked as level 3 are based on information from multiple media reports, while level 4 incidents are based on information from at least one NGO, IGO, or another humanitarian actor with direct knowledge of the incident. Incidents ranked at level 5 are based on information from official sources such as coroners, medical examiners, or government officials OR from multiple humanitarian actors.
Comments	Brief description narrating additional facts about the death. If no extra information is available, this is left blank.

^[1] The Missing Migrants Project is an “incident-based” dataset, meaning that each entry in the database represents a single occurrence in which an individual or group of individuals die during migration or at international borders in one particular place and time. In some cases, official statistics are not disaggregated by the incident, in which case the entry will be marked as a “cumulative total.”

^[2] See for example RMMS (2016) Forgotten Fatalities in North Africa. Available from https://reliefweb.int/report/world/forgotten-fatalities-number-migrant-deaths-reaching-mediterranean.