It's a temptation, having read so many reviews of Superfreakonomics by Steven Levitt and Stephen Dubner, to reply to the reviews rather than giving my own views. And most of them have focussed on the controversial chapter on climate change, which critics have interpreted as a claim that there are some easy technological fixes. I'm going to resist the temptation and leave a few comments about that chapter until the end of my review.

My other difficulty in reviewing Superfreakonomics is that I was teased, entirely fairly, for criticizing Freakonomics for its glibness when I'd published myself a book called Sex, Drugs and Economics which had been massively less successful commercially. Dare I risk once again the charge of sour grapes?

Well, my reaction to this follow-up isn't entirely negative. It's enjoyable to read, perfect for Tube journeys. There are some extremely interesting parts – more on these below.

Having said this, I don't think there's very much economics at all in Superfreakonomics. Levitt and Dubner claim that it's about micro, not macro. It isn't really. It's about empirical social science but there's little overlap with the domain of economics, which is choice about the allocation of resources and activity. Although I'm usually all for economic imperialism, Levitt and Dubner stray too far for me, and head off into the same kind of territory that Malcolm Gladwell patrols in books such as Outliers and The Tipping Point, or Sunstein and Thaler in Nudge. (And why not? Sales figures suggest there's a large public appetite for it.)

The early chapters are closer to economic decision making, and the first tries to draw readers in with the economics of prostitution. It falls between two stools, I think, being neither a polished piece of journalism nor a clear economic analysis. (My first chapter in Sex, Drugs and Economics does the latter job better, I think, though they do have great data from the Chicago streets – I will post my chapter as soon as I'm able so readers can make their own assessment.) The first is the weakest chapter of the book by far, and the second is also all over the place in terms of its structure. I think it's trying to use statistics on mortality and the risk of death to make some points about how to interpret evidence, but that's my retrospective structure superimposed on the text.

The second half of the book is substantially better and more interesting. The terrain is decision-making in the face of an array of imperfect data and the need to structure incentives in order to change people's behavior. This is a fascinating subject and the examples given here are very telling. Many of the examples are medical, and so overlap with Atul Gawande's wonderful book Better. Improving outcomes in areas such as health not only requires the scientific breakthrough which enables identification of the causes of a problem – incidence of puerperal fever, low productivity, high infection rates in hospitals etc – but also the psychological breakthrough which makes people change their habits. Freakonomics and Gawande's Better both look at how hard it is to get doctors to wash their hands, the only way to minimize MRSA-type infections in hospitals. Levitt and Dubner report that one effective method was the use as screensavers of the cultured hand prints of surgeons (taken at lunch!) which showed in glorious technicolor their collection of bacteria.

Often the most effective interventions are structural not behavioural – one example given here is the much greater effectiveness of circumcision compared to greater use of condoms to limit HIV/AIDS infection rates in Africa. There are also some terrific examples of the iron law of unintended consequences – laws intended to protect wildlife which induces landowners to cut down trees in order to clear out all the wildlife that might be eligible, for example.

The controversial climate change chapter takes the same perspective – what does the evidence say? what actions will be effective? As the authors note, climate change does take many people into the realm of belief rather than openness to evidence. Bravely, however, they compare different sources of contributions to greenhouse gases and suggest we can do more by switching from eating beef to eating kangaroos than by switching from conventional cars to hybrids. They note the great uncertainty about the human contribution to global warming, the existence of large swings anyway in global climate, and question the contribution of carbon dioxide as opposed to other gases and water vapour (or rather itslack over the oceans). The most telling point is perhaps their comparison of the forecasts about climate with macroeconomic forecasting – and we all know how flawed the latter has been.

As someone who is cerainly willing to take some actions to increase my energy efficiency, yet made queasy by the intolerant passion of the climate change doomsters, I found this chapter very interesting. I'd certainly like to see governments test some of the geo-engineering ideas presented here. If there is going to be catastrophic climate change, better to approach policy choices with an open mind than a closed one. So I'm glad Levitt and Dubner have weighed into this debate. For all that it has some flaws, Superfreakonomics is worth reading for this chapter alone – the sales will be a good reward for the authors' bravery in taking on the climate change priesthood.