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Elephants in the room: The top ten problems in information about migration in the UK

04 Apr 2011

A new report by The Migration Observatory at the University of Oxford reveals ten key problems with the UK’s evidence base on migrants and migration – with profound implications for public debate and policy making.

The report Top Ten Problems in the Evidence Base for Public Debate and Policy-Making on Immigration in the UK has been published by the Migration Observatory – a new multi-media platform providing independent, evidence-based analysis about migration issues from scholars across the University of Oxford.

Dr Martin Ruhs, Director of the Migration Observatory, said: “There are many disagreements about migration in the UK, but one thing that unites everyone is that for many years there have been serious problems with the evidence base. Reform of immigration policy is currently a major government priority, which clearly requires solid evidence on which to base changes to the system.“ The top ten data and analysis limitations identified by the Migration Observatory report are (Please note – these are numbered for convenience rather than by importance):

  1. Emigration: The limited data about who is leaving the country mean that net migration figures – which are based on the balance between those leaving and those entering the UK – are very imprecise.
  2. Immigration: There are substantial discrepancies between the three data sources that provide information about people entering the UK – the International Passenger Survey (IPS), visa data and passenger entry data.
  3. Net-migration: Two major data sources (the IPS and the Annual Population Survey) disagree significantly about the level and changes of net-migration over time.
  4. The immigration status of migrants in the UK: While we know the purpose for which people have been granted access to the UK – work, family reunion, political asylum, etc – there is no systematic evidence about the number, characteristics and impacts of migrants on different types of residence permits in the UK.
  5. Local area statistics on migrants: The most reliable tool we have to measure the number of migrants at the local level is the Census, which is only undertaken every ten years. In intercensal years, survey data provide very imprecise estimates of migrants in local areas, making it extremely difficult for local government or services to estimate the resources they need accurately.
  6. Public opinion: Public opinion data clearly show that the majority of the British resident population would prefer reduced immigration. But the evidence base lacks detailed information on a crucial issue – how do members of the public define “immigrants?”
  7. Migrants’ impacts on public services: There is very limited systematic data and analysis about migrants’ use of public services, especially health and education, and even less information about migrants’ contributions to the provision of public services.
  8. Impacts on housing: We know little about how immigration impacts, directly and indirectly, on house prices, rents, and social housing at national and local levels.
  9. Student migration: The evidence base lacks sufficient information about the number of students, the extent of non-compliance with immigration rules among international students, and the impact of foreign students on the broader economy and society.
  10. Irregular migrants (also referred to as undocumented or illegal migrants): Data and information about the number, characteristics and impacts of irregular migrants are extremely limited.

Dr Ruhs added: “No country can realistically expect to have perfect information about migration – collecting data can be complex and expensive – but if we want to have informed debate and effective policy-making, we need to make sure that we have the best possible evidence.”


For further information contact

Rob McNeil, Senior Media Analyst, The Migration Observatory at the University of Oxford. e: robert.mcneil@compas.ox.ac.uk; tel: 01865 274568; Mob: 07500 970081

Notes for Editors

To download a copy of the report visit: www.migrationobservatory.ox.ac.uk/top-ten

To visit the Migration Observatory go to www.migrationobservatory.ox.ac.uk.

Follow us on Twitter @MigObs.

  • Based at the ESRC Centre on Migration, Policy and Society (COMPAS) at the University of Oxford, the Migration Observatory provides independent, authoritative, evidence-based analysis of data on migration and migrants in the UK, to inform media, public and policy debates, and to generate high quality research on international migration and public policy issues. The Observatory’s analysis involves experts from a wide range of disciplines and departments at the University of Oxford.
  • The Migration Observatory is funded by: Unbound Philanthropy; the Diana, Princess of Wales Memorial Fund and the Barrow Cadbury Trust.
  • The Centre on Migration, Policy and Society (COMPAS) at the University of Oxford conducts high quality research in order to develop theory and knowledge, inform policy-making and public debate, and engage users of research within the field of migration. For further detail see the COMPAS website: www.compas.ox.ac.uk/. 
  • COMPAS is core funded by the Economic and Social Research Council (ESRC) www.esrc.ac.uk/

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If you would like to make a press enquiry, please contact:

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