On More or Less this week we went behind the results from medical trials, found out how to put a cash value on items such as graffiti-free walls and why it easier to learn maths if you speak Cantonese rather than English.
Professor of Clinical Neurology at Oxford University, George Ebers, explained why he thinks clinical trials of the multiple sclerosis drug beta interferon may have over stated the drug's effectiveness and why there are now doubts about whether the drug has any effect in slowing the onset of the secondary stage of the disease.
And Professor Stephen Senn, a medical statistician, explained why medical trials often have to use "surrogate end points", ie markers of the disease, rather than the long term therapeutic outcomes.
The Gershon review of public sector efficiency contained an estimate of "non-cashable efficiencies".
This means putting a financial value on things that you cannot realise in cash terms such as a happier workforce, cleaner streets and faster response times.
Local authorities even have financial targets to meet for these hard to value assets. Nottingham University's Colin Talbot calls these "fantasy savings".
National efficiency champion and chief executive of the London Borough of Lewisham, Barry Quirk, explained how local authorities come up with a cash valuation for something from which they cannot generate any money.
"Fear drives one teenage boy in ten to carry a gun" according to a front page headline in The Times this week.
We manage to get the figure down to something much less worrying by looking at the research itself.
Maths and languages
And our reporter Mayo Ogunlabi looked at why it is harder to learn maths if you speak English or French than if you speak Hindi or a Chinese dialect.
More Or Less was broadcast on Thursday, 7 July, 2005 at 1500 BST on BBC Radio 4.
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