Your questions answered on immigration and migration

BBC East Yorkshire and Lincolnshire has looked at immigration and migration across the country, and the impact it is having on communities, public services and society.

A complex topic, the BBC aims to cut through the rhetoric and get to the facts, going beyond the headlines and politics to put the issue into context.

We asked for your questions on the matter.

Here is a selection answered by Dr Madeleine Sumption MBE, who is the director of the Migration Observatory at Oxford University. It provides impartial, independent and evidence-based analysis of data on migration and migrants in the UK to inform media, public and policy debates.

Jenny Lewis, from Grantham, wants to know how many people from abroad work in heath care, and if the NHS and social care could survive without them.

In response, Dr Sumption said the NHS relied quite heavily on overseas doctors and nurses, as does the social care sector.

She said it was difficult to imagine a scenario with no overseas recruitment, but added it would depend on what else we did as a country.

"For example, whether we increase the number of domestic nurses that we train – or if you look at the care sector – whether the government improves pay and conditions."

David Bedford, 59, from Lincolnshire, wants to know what percentage of Eastern Europeans work in the NHS.

Dr Sumption says while there is no specific data on Eastern European workers, if you look at the health and care sectors together, one in six workers come from overseas - making health "slightly more reliant" on overseas workers than other industries.

Ray Bennett, from Little Carlton, asks why people are risking their lives in small boats to get to the UK, rather than claiming asylum in the first safe country they get to?

Dr Sumption says: "In terms of the risks, one thing that is quite interesting is that people are willing to take quite extraordinary risks… to make that journey."

She says if you look at the numbers coming to the UK in small boats as a share of overall migration "it's actually quite low".

However, she adds: "That doesn't mean we shouldn't be talking about it."

"What's happening on the small boats is a dangerous form of migration – the costs are higher, so I think it's reasonable there has been more of a focus on it."

Stuart, from Lincolnshire, asks what impact immigration was having on UK crime rates.

"There has been a little bit of research on this – which has so far not actually found much of a connection between immigration and crime," says Dr Sumption.

However, she says some studies from the US and UK suggest that immigration might have actually decreased crime.

"This is an area which needs more evidence," she adds.

Steve Wright, 75, from Lincolnshire, suggests migrants on benefits are "costing the country a fortune".

Dr Sumption: "If you look at the total cost of migration and the benefits in terms of the taxes that people pay, it seems migrants pay more or less the amount of taxes it would take to provide them with benefits and other public services.

"It does, of course, vary quite a lot, so those on low incomes are much more likely to be net recipients from the system. At the same time, those who are earning a lot are paying a lot of tax and subsidising others."