In our General Election Factcheck 2015 report, we include five common pitfalls when it comes to political claims. These are errors that politicians often fall into, and are all too easy to fall for. We've made these mistakes ourselves at times, and know how hard they can be to spot. Here's our guide to how to identify and avoid them.
In 2006, six men were taken critically ill during clinical trials for a new drug: it was the first time the drug had been tested in humans. While cases as serious as this are very unusual, they serve as a useful reminder of the importance of recognising what's not known. If this drug had simply been given to patients without being sure of its effects, the result would have been catastrophic.
We are often very quick to assign praise or blame to the government of the day for what happens on its watch. We hear claims too from both the incumbent parties about their record in government, and by the opposition parties on things they say haven't worked (or that they think could have gone better).
But a frustration for all parties and voters is that sometimes it's just too early to say whether reforms have had a positive or negative effect.
One such example is free schools. Both the Conservatives and Labour has made claims as to how well free schools are working—the Conservatives saying free schools are "delivering better education for the children who need it most" and Labour saying it's a "wasteful and poorly performing" programme.
As we discuss earlier in this report when we factcheck these claims head-to-head, it's really just too early to say.
So we can't say anything meaningful about their performance until there's more evidence available.
Staying with education, the universal infant free school meals policy was introduced to "improve academic attainment and save families money". The Liberal Democrats have pledged to extend the policy to all primary pupils.
That was after a pilot scheme was used to test out the policy, the evaluation of which found that performance and healthy eating by primary pupils in schools involved in the pilot improved.
But that research wasn't able to find evidence of significant health benefits resulting from the scheme, nor was it able to connect up evidence for why pupils receiving the meals were seeing their performance improve.
Since then, we haven't seen any more research which looks at whether this improved performance has continued and whether or not the free meals were behind the improvement.
On a positive note, the Liberal Democrats have been careful not to make any claims about the effect of the policy, and have pledged to extend the meals to all primary schools "following a full evaluation" of the initial policy.
It may sound pedantic to say "It's too early to tell" but it might be preferable to pouring money or votes into plans that don't work.
Isn't it nice to have the whole picture?
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