Over on Bloggerheads Tim Ireland dismisses a poll on Abortion quoted during yesterdays Parliamentary debate as “being conducted by the Christian Institute [so] it’s on him if the poll turns out to have been conducted on the back of a hymn sheet in a church car park.”
The tables for the poll are here, and while it was commissioned by the Christian Institute, it was carried out by ComRes, a proper polling company using proper a quasi-random phone sample.
Where the problems begin is with the questions themselves. They didn’t ask people straight about what they thought the time limit for abortion should be, they first primed them with an argument in favour of reducing it. Respondents were told that in other European countries the limit was 12 weeks, and then asked their opinion. 58% thought the time limit should be reduced, with 24% of women taking the hint and picking 12 weeks. In a second question respondents were told that in one neonatal unit 5 out of 7 babies born at 22 weeks survived. 60% then thought the time limit should be reduced from 24 weeks.
Now, questions like this do have legitimate uses in message testing or deliberative polling to see how well arguments work to change opinions. If they are presented in the correct way, they are perfectly good questions – for example, the Christian Institute published the first question as being “whether they thought the UK should lower its abortion time limit in light of the fact that in most other EU countries the limit is 12 weeks or lower“, which is exactly what was asked.
What the questions don’t show is that X percentage of people want to see the time limit for abortion reduced, anymore than a question prefaced with a pro-choice argument would show people opposed a reduction. The best way to ask a survey question is to give the minimal amount of information, since for every bit of background information you provide you risk skewing the answer or, by making them better informed than other people, making your sample unrepresentative.
The cynical old souls reading this will jump to the conclusion that clients go around deliberately asking pollsters for skewed polls that give them the answers they want. In my experience it doesn’t actually work like that. Most common is that clients think that other polls are skewed, because the public don’t understand, and if they were aware of this vital bit of information they would be much better informed and the answers so much more reflective of what they really think. Then we have to explain that actually, polls are supposed to measure public opinion as it is, not how it we would like it to be if they were better informed. It normally isn’t an attempt to mislead, it’s often just misunderstanding of what fair question wording is.
Of course, even a stopped clock tells the right time twice a day, so just because these questions can’t be taken to show it, doesn’t mean a majority of people don’t support a shorter time limit on abortion. Polls with less skewed wording also show support for a reduction. A YouGov poll in the Sunday Times two months ago asked if people supported the status quo, or the 20 week amendment. 48% supported 20 weeks compared to 35% supporting 24% weeks, 8% wanted it banned altogether (other options weren’t offered, so no doubt some people would have gone for 22 weeks if they could). A MORI poll for the Observer in 2006 found 33% thought the current limit was right, 4% wanted a longer limit, 42% a tighter limit and 10% a total ban.