Réseau Quetelet

Enquête : Migrations between Africa and Europe - MAFE Senegal (2008)


  • INED - Institut National d'Etudes Démographiques
  • UCAD - Université Cheikh Anta Diop
  • FIERI - Forum Internazionale ed Europeo di Ricerche sull'immigrazione
  • UPF - University Pompeu Fabra
  • CSIC - Consejo Superior de Investigaciones Científicas


  • European Community's Seventh Framework Programme
  • INED - Institut National d'Etudes Démographiques
  • ANR - Agence Nationale de la Recherche
  • IDF - Région Ile de France
  • FSP programme "International Migrations, territorial reorganizations and development of the countries of the South"


  • INED - Institut National d'Etudes Démographiques


The MAFE project is a major research initiative focused on migration between Sub-Saharan Africa and Europe. It brings together ten European and African research centres working on international migration.

In the early XXIth Century, international migration from Sub-Saharan Africa to Europe has generated increasing public and policy attention. The flotilla of boats bringing would-be migrants to the Canary Islands, and attempts to reach Spanish territory in Ceuta and Mellila have drawn a rapid response from Europe in the form of new policy measures. Yet the scope, nature and likely development of Sub-Saharan African migration to Europe remained poorly understood, and, as a result, European polices may be ineffective. A major cause of this lack of understanding was the absence of comprehensive data on the causes of migration and circulation between Africa and Europe.

The MAFE project aimed at overcoming this lack of understanding by collecting unique data on the characteristics and behavior of migrants from Sub-Saharan countries to Europe. The key notion underpinning the project was that migration must not only be seen as a one-way flow from Africa to Europe. The argument was that return migration, circulation and transnational practices are significant and must be understood in order to design better migration policy.

The MAFE project focused on migration flows between Europe (Belgium, France, Italy, the Netherlands, Spain and the UK) and Senegal, the Democratic Republic of Congo and Ghana, which together accounted for over a quarter of all African migration to the EU at the time of the survey. In each of these "migration systems", the survey was designed to document four key areas:
- Patterns of migration :
*the socio-demographic characteristics of migrants,
*the routes of migration from Africa to Europe, and
*the patterns of return migration and circulation.
- Determinants of migration: looking at departure, but also return and circulation and taking into account the whole set of possible destinations.
- Migration and Development: MAFE documents some of the socio-economic changes driven by international migration, looking as often as possible at both ends of the Afro-European migration system, at the individual level.
- Migrations and Families: the data collected by the MAFE project can be used to study all sorts of interactions between family formation and international migration. Although the survey was primarily designed to study international migration, it can also be used to study other phenomena, especially in Africa: domestic mobility, labor market participation, family formation, etc.
Comparable data was collected in both 3 sending and 6 destination countries, i.e. in sub-Saharan Africa and in Europe. The data are longitudinal - including retrospective migration, education, work and family histories for individuals - and multi-level - (with data collected at the individual and household levels, in addition of macro-contextual data).

Please consult the official MAFE website for further details : http://www.mafeproject.com/

Dates de collecte

  • Senegal pilot survey - début : 07/2007
  • Senegal pilot survey - fin : 08/2007
  • Senegal (Dakar) survey - début : 01/2008
  • Senegal (Dakar) survey - fin : 06/2008
  • Italy survey - début : 03/2008
  • Italy survey - fin : 06/2008
  • France survey - début : 03/2008
  • France survey - fin : 07/2008
  • Spain survey - début : 05/2008
  • Spain survey - fin : 06/2008



Couverture géographique

Six European countries and three African countries participated in the MAFE surveys. Data collection was carried out in both sending countries in Africa and destination countries in Europe, in order to constitute transnational samples.
For MAFE Senegal, data was collected in Senegal (African part) and France, Italy and Spain (European part).

Unité d'analyse



Household: Households selected randomly from the updated list of households in the selected primary sampling units. Two strata were distinguished: the households with migrants and those without migrants.
Individual: People aged 25-75 at the time of the survey, born in Senegal and who have/had Senegalese citizenship. This lower age limit was set in order to obtain informative life histories. By not including respondents younger than 25, the resources were used more effectively. The place of birth criterion was used to exclude people who were born out of their country of origin in order to exclude second generation migrants in Europe and to increase the homogeneity of sample.
Up to two return migrants and partners of migrants, and one randomly selected other eligible person. Return migrants were eligible if their first departure was above at 18 or over.

In all the European countries, the surveys were conducted among males and females who were aged 25 and over at the time of the surveys, and who were 18 or over when they had left Africa for the first time for at least one year. For MAFE Senegal, only migrants from Senegal were interviewed. This was a way to reinforce the homogeneity of the sample by excluding people of the 1.5 generation who are often "passive" migrants.

In theory, surveyed individuals must be representative of the whole population with these characteristics in the departure region and in the destination countries. The sample is composed of males and females. In Europe, in spite of a gender demographic disequilibrium, the objective was to include 50% of males and 50% of females in order to allow gender analyses.

Méthode d'échantillonnage


A three-stage stratified random sample was used. At the first stage, primary sampling units (census district) were selected randomly with varying probabilities. At the second stage, households were selected randomly in each of the selected primary sampling units (PSUs). At the third stage, individuals were selected within the households.

a) Selection of primary sampling units (first stage)
In the Senegal survey, the sample was designed to be probabilistic and representative of the Dakar region, and at the same time to maximize the chance of reaching households 'affected' by international migration (rare population). The sampling frame used to select the primary sampling units was the 2002 Population Census. The census districts (CD) -which are usually used as the primary sampling units in surveys in Senegal - have an average size of 100 households in urban areas. 60 primary sampling units were randomly selected at the first stage. This number of primary sampling units allows reaching a balance between a large dispersion of households (which decreases sampling errors) and a more concentrated sample (which reduces costs).
The region of Dakar was divided into 10 strata of equal size, according to the % of migrant households within each of them (in average, 11.6% of the households were 'migrants'). 6 CD's per stratum were drawn, with a probability proportional to the number of households within each CD. In other words, census districts with a large number of migrants were more likely to be selected than those with low numbers of migrants. This approach increases the number of migrants interviewed in the individual survey, while still having a probabilistic sample representative of the target area.
The listing of the households in the 60 selected primary sampling units was updated in order to select the sample of households. This stage was essential because a lot of changing occurred in some large neighbourhoods of Dakar since the previous census (2002), especially in suburban areas. This counting also allowed distinguishing between households with and without migrants.

b) Selection of households (second stage)
The following approach was used in MAFE-Senegal:
- Households were selected randomly (using systematic random sampling) from the updated list of households in the selected PSUs. Two strata were distinguished: the households with migrants and those without migrants. A maximum of 50% of households with migrants were drawn in each district. Selected households that could not be reached (absence, refusals,…) were not replaced during the fieldwork. Replacement would distort the computation of sampling weights, and could also lead to bias the sample. To take account of refusals and absences of households, 22 households were selected to reach an effective sample size of 20 households per CD on average (a total of 1 200 households in Dakar region was to be reached).

c) Selection of individuals (third stage)
Next, individuals were selected within households for the life history survey. In each household, individuals were classified into 3 strata (which do not overlap):
- Return migrants, who were aged 18 or over at their (first) departure (or whose age at departure is unknown) ;
- Spouses/partners of migrants (if the spouse/partner is not a return migrant himself/herself) ;
- Other people.
Then, a simple random sample was done in each household to select:
- Up to 2 return migrants (random selection if more than two in the households, all the return migrants were selected if not more than two in the household)
- Up to 2 Spouses/partners of migrants (random selection if more than two in the household)
- Another individual.
In Senegal, an additional condition was that people had the Senegalese citizenship at birth. This condition was dropped in the Ghana and DR Congo surveys.

Two types of questionnaires were used in the departure countries: the household questionnaire and the individual life history questionnaire.
- The first questionnaire was used among a representative sample of households in the target region.
- The second questionnaire was used among a sample of individuals in the selected households, targeting both return migrants and non-migrants. The household questionnaire was thus used as the sampling frame for the selection of individual respondents.


The objective of the survey was to obtain a sample 'as representative as possible' of the African populations (Congolese, Ghanaian, Senegalese) in the destination countries (150 individuals per origin and destination country). The way the sample was constituted may vary across countries, but some common principles were respected:
- The composition of the sample should be as close as possible to the population of (Congolese, Ghanaian, Senegalese) migrants in the country in terms of gender, geographic distribution, age, socio-economic category or occupation.
- One exception: the sample should be gender balanced. Males and females should be equally represented in order to allow gender analyses.
- Samples in origin and destination may be linked, but migrants with weak or no relationships at origin should not be excluded from the sample.
- Both documented and undocumented migrants should be represented in the sample.

For MAFE Senegal, 200 Senegalese were to be sampled in each country (France, Spain and Italy).
The quota method was preferred in France and Italy to collect information on Senegalese migrants. In Spain, a sample of Senegalese migrants was drawn in the Padron. This source appears as a unique sampling opportunity in Europe since it is annually updated and includes all migrants, even the undocumented ones.

The Senegalese sample in Europe was made up from two types of samples:
- a linked sample of respondents, whose contacts were obtained in Senegal through the household survey. The module D of the HH questionnaire was designed to help the collection of contacts. It had to be entered and transmitted securely to the destination countries before data collection started in Europe. The contacts validity was checked before the fieldwork began. For Senegalese in France, 156 contacts were collected but only 54% of them were actually usable (correct contacts but a large amount were not interviewed). In Italy, almost no contact could be used. The efficiency of this method varies a lot according to the context ;
- an additional sample made up in each country to reach the expected sample size. The size of the additional sample is unknown until the contacts in the origin country have been obtained. The method of selection of this sample varied across countries (selection in a municipal register, through migrant associations, street recruitment, by snowballing methods…).

Regions were selected to cover the largest possible population of Senegalese in the country.

* France *
- Target areas: 3 regions comprising 64% of Senegalese people in France (Ile de France, Rhône-Alpes and Provence-Alpes-Côte d'Azur)
- Sample size: 201
- Quotas: By age, gender and socioeconomic status
- Recruitment methods: Selection from contacts obtained in Senegal, public spaces, migrant associations, snowballing, interviewers' contacts

* Italy *
- Target areas: Lombardia, Emilia Romagna, Toscana, Campania
- Sample size: 205
- Quotas: By age and gender
- Recruitment methods: Selection from contacts obtained in Senegal, public spaces, migrant associations, snowballing, interviewers' contacts

* Spain *
- Target areas: 12 provinces: Almería (Andalucía), Alicante & Valencia (Comunidad Valenciana), Barcelona, Lérida, Tarragona & Gerona (Cataluña), Madrid (Comunidad de Madrid), Zaragoza (Aragón), Las Palmas (Islas Canarias), Murcia (Comunidad Autónoma de Murcia), Baleares (Islas Baleares)
- Sample size: 200 (+ an additional sample of 400 people expected in 2010)
- Quotas: Random sample from Padron
- Recruitment methods: Population register (Padron), contacts obtained in Senegal, interviewers' contacts
- Note: a quota was imposed and respected: the proportion of interviewed migrants living in areas with a large concentration of Senegalese residents had to be equivalent to the real proportion of Senegalese migrants living in those areas in the selected regions

Nombre d'observations


Méthode de collecte

The general strategy was the following one:
1. A household survey was conducted among a sample of households in the capital cities in Africa (household questionnaire in origin countries);
2. A life history survey among a sample of individual respondents was conducted in the departure countries (non migrants, return migrants and spouses of migrants). The individual respondents were selected from the households in the origin countries (individual questionnaire in origin countries);
3. A life history survey was carried out among migrants in destination countries (individual questionnaire in destination countries).
All the surveys were done using paper questionnaires through face-to-face interviews.

In Senegal, the survey was organized in two stages. The first stage consisted in collecting household data. At the end of that stage, selected data of the household questionnaire were entered in order to constitute the sampling frames for individual surveys in Africa and in Europe. The household survey thus precedes the collection of life histories both in Africa and Europe.
NB: In Senegal, the interviewers who did the work in a household did also the work for the individuals of this precise household. It was a way to create a confidence relationship.
The average duration of interviews for the household questionnaire was about 45 minutes-1 hour in Senegal. The average duration of the biographic questionnaire was also around 45 minutes, but it varied greatly depending on the age and migration status of the respondents.

In Europe, the moment for data collection depended on the selection method. In MAFE-Senegal, the fieldwork could start only after completion of the household survey. As a consequence, the fieldwork for the biographic questionnaires was done almost at the same time in all countries.
The work of the interviewers included three stages:
o The interviewers first had to set up an appointment with respondents by using the phone contacts or another source of recruitment (except in cases persons were directly available). Interviewers needed to confirm the appointment. The choice of the place and time of the interview were left to the respondents.
o The interview was then done. The average duration of the interviews was approximately 1h45 in France. In most cases, interviews were carried out at the house of the respondents, but it also took places in various places (pubs, street, office…). The interviews were done during weekdays or week-ends, at various times.
o Finally interviewers were asked to read quickly the completed questionnaire as soon as possible after the interview, in order to detect any missing parts or inconsistencies, and correct them on the spot. Approximately one additional hour was necessary for this.
In all the countries, the respondents were offered a small gift at the end of the interview. In most countries, this was a calling card. The value of the gift varied between 5 € (Italy) and £15 (UK). In all the countries, the gift was very much appreciated. Although the gift was offered after the interview, some participants knew in advance they would receive it.
Recruitment by snowballing also meant that respondents were sometimes aware they would receive a gift. Although this may have facilitated the recruitments of some persons, it may have affected negatively the composition of the sample.