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Last week, the UK's most popular newspaper, the Sun, ran the headline "1 in 5 Brit Muslims' sympathy for jihadis". Where did that statistic come from and how reliable is it?

The Sun's headline immediately caused a backlash - angry videos of British Muslims disputing the "1 in 5" figure soon appeared on social media and Twitter users took up the hashtag #1in5muslims to make fun of the story. The newspaper regulator, the Independent Press Standards Organisation, received more than 2,600 complaints.

The Sun's figures came from research carried out by polling company Survation, which conducted phone interviews with 1,000 British Muslims after the recent attacks in Paris. One of the questions was: Which of the following statements is closest to your view?

I have a lot of sympathy with young Muslims who leave the UK to join fighters in Syria.

I have some sympathy with young Muslims who leave the UK to join fighters in Syria.

I have no sympathy with young Muslims who leave the UK to join fighters in Syria.

Don't know.

The word "jihadis", which is used in the headline, does not appear in the question. This might be significant because not everyone who travels to Syria is necessarily going to fight for the so-called Islamic State or other militant Islamist groups - some could be going to join rebel groups opposed to IS.

When people answered the question, 4% said they had a lot of sympathy and 14% said they had some sympathy - a total of 19%, which is the figure the Sun used.

Image copyright News UK

But the word "sympathy" is ambiguous and using it casts doubt on the result, says Manchester University's Maria Sobolewska, an expert on polling minority groups.

In the Concise Oxford English Dictionary, the first two definitions of the word are:

Feelings of pity and sorrow for someone else's misfortune.

Understanding between people; common feeling.

"Did [the respondents] simply mean that they felt the situation for Muslims is very hard around the world, with a lot of wars and conflict, and perhaps prejudice in Western Europe, and therefore, this particular person feels some sympathy with how desperation may lead some young people to terrorism?" asks Sobolewska. "Is it just an emotional understanding? Or is it actually weak or tacit support of terrorism? I really think making that leap in to the second conclusion is taking it a bit too far."

This distinction is also made by someone who helped carry out the poll. Writing anonymously on the news website Vice, they say they are uneasy with the way such a complex issue was presented.

"None of the people I polled who responded to the question with the 'some sympathy' answer supported jihadis," they write. "One woman gave me thoughtful, considered answers to every question. She thought that David Cameron would probably be right to bomb Syria, and that Muslims did have a responsibility to condemn terrorist attacks carried out in the name of Islam. But she also had some sympathy with young British Muslims who joined fighters in Syria. 'They're brainwashed, I feel sorry for them,' she said. And so I ticked the box, 'I have some sympathy for young British Muslims who go to join fighters in Syria.'"

So why was the word "sympathy" used? "It was chosen deliberately to exactly match the wording of previous polling that we've done on this topic earlier in the year, and so to enable comparisons to be drawn," says Patrick Brione from Survation.

When compared to research commissioned by Sky News in March, the new survey suggests that among British Muslims, sympathy for people joining fighters in Syria has fallen.

The earlier poll also asked non-Muslims the same question, with around one in seven expressing at least some sympathy. Non-Muslims weren't included in the Sun's poll.

To find out how many people are actively in favour of the actions of fighters in Syria, Sobolewska thinks they need to ask a different question.

"I'm a great fan of saying what you mean," she says. "Using the word 'support' would have been a good start. So 'Do you support actions, such as the Hebdo attacks or the Paris attacks?' And I think, what we would see is that the level of support for these questions would be within that kind of two, three, four, maybe five per cent."

She says that after the attacks in London in 2005, a number of polls asked very direct questions about whether British Muslims supported the bombings or felt they were justified.

"Normally this expression of clear support has yielded smaller numbers - so there were anything from 2%, which is obviously statistically insignificant in a poll that has about a 3% margin of error, up to 9% even on some occasions. This is a clear message that a very, very small proportion of British Muslims may have thoughts that are in fact supportive of these kind of terrorist attacks."

Image copyright Getty Images Image caption A banner outside the Reims mosque after the Paris attacks reads "Muslims in mourning"

Since the Sun's story was published, Survation has distanced itself from the newspaper's interpretation of the research. "We don't support or endorse the way they've chosen to portray the story and that headline," says Brione, adding that it was a "bit of a shock to see it portrayed in such a stark way".

A statement from the Sun said: "It is not for a polling company to endorse or otherwise the editorial interpretation of a survey. The Sun published the poll's findings clearly and accurately, including the questions in full."

A spokesman added: "The fact remains that a significant minority of Muslims have sympathy for the actions of extremists. That is a subject worthy of discussion and the Sun believes that it must be appropriate for that conversation to take place."

The Sun's sister paper, the Times, also published a story based on the poll, but has since issued a correction saying its headline "One in five British Muslims has sympathy for Isis" was "misleading".

On an international level, the Pew Research Center recently published a report looking at attitudes to IS in 11 countries with "significant Muslim populations".

"People from Nigeria to Jordan to Indonesia overwhelmingly expressed negative views of ISIS," it said. "And in those countries with mixed religious and ethnic populations, negative views of ISIS cut across these lines."

In Lebanon, Burkina Faso and Malaysia there was barely any gap between the opinions of Muslims and non-Muslims on this question. Although in Nigeria 20% of Muslims had a favourable view of IS compared to 7% of Christians.

One exception was Pakistan where 62% said they had no definite opinion of IS.

"In some countries, like Lebanon, it's 100% unfavourable so their image is overall quite negative," says Steven Kull, a political psychologist at the University of Maryland.

But he suspects there are people who find some of IS's ideas attractive, believing it is "very committed to Sharia law and that it has a reputation of not being corrupt or that it is standing up to Western forces that many of them perceive as being hostile to Islam."

More or Less is broadcast on BBC Radio 4 and the World Service.

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