Thursday, 19 November 2009

A few things Alcohol Action NZ won't tell you about alcohol

Doug Sellman's article from last week's Press, noted last week, is still bugging me. A few things Alcohol Action NZ won't tell you about alcohol:
  • Sellman lists alcohol alongside scary things like asbestos as a known carcinogen (in the Press article). But here are some other known carcinogens that could have been listed alongside alcohol instead and would have been perhaps a bit less scary: ciclosporin (used to prevent organ rejection after transplant), estrogen-based oral contraceptives and menopausal therapy, risky sex (Hepatitis B & C, HPV, HIV), the sun, mineral oils, salted fish, wood dust, painting, boot and shoe manufacture and repair.

  • He cites Corrao et al as saying "Alcohol cardio-protection has been talked up". You might think this means there's no protective effect. But that's not what Corrao says. Corrao shows rather that there are strong protective effects from alcohol consumption; it's just that they're slightly smaller in a subset of higher quality studies than in the full set of studies. So, where a full sample of studies finds the risk-minimizing consumption of alcohol at 25 grams per day (2.5 standard drinks), the protection washing out at 90 grams per day (9 standard drinks) and harmful coronary effects kicking in at 113 grams per day, the "selected studies" find protection is maximized at 20 grams per day, protective effects lost at 72 grams per day, and harmful coronary effects kicking in at 89 grams per day. What a shocking "talking up" of cardio-protection! Harmful effects kick in at 9 drinks per day rather than at 11! You should aim to drink 2 rather than 2.5 standard drinks per day if you want to minimize your risk of heart disease! Shocking! It looks like you have to trade off increased cancer risk against reduced risk of heart disease over most folks' relevant ranges of alcohol consumption.

  • Notes high proportions of arrests and crimes that are "related" to alcohol. But what I've never seen numbers on is what proportion those "alcohol related" crimes would have taken place in the absence of alcohol. You could just as easily say that 100% of crimes are "Oxygen related", 50% are mullet-related and 25% involve the wearing of t-shirts that say "No Fear". Ok, without the oxygen, none of those oxygen-related crimes would have taken place. But would a policy getting rid of No Fear t-shirts really prevent crime? Mightn't criminals switch to even riskier shirts? This is actually a reasonably serious point. If you ramp up the price of alcohol, how many criminals switch to P before going out to do nasty stuff? One of the country's more prominent criminologists suggests in informal chats that he reckons about 60% of these "alcohol-related" crimes would have taken place anyway even if alcohol disappeared; the actual crime-costs of alcohol are then about 60% lower than typically reported as alcohol in those cases is more like wearing a No Fear t-shirt: just something criminals like to do while offending but wouldn't stop them from offending in its absence.

  • And, Alcohol Action NZ leaves out, of course, all the academic literature on things like drinkers earning more money and the strong anecdotal evidence (collected by my casual observation) that drinkers are simply better people, on average, than teetotalers and healthists.


  1. I really wish there was a 'I told you so clause' attached to legislation - i.e. we let the Healthists implement their policies on a trial basis for 6 months. When crime, road accidents and other externalities don't magically decrease, their policies are canned. In return for this generous trial of their failed policies they are now obliged to STFU for at least 10 years.

  2. The reply would, of course, be that outcomes would have been EVEN WORSE absent the policy.

    What you really need are some conditional markets. In market A, you trade contracts that pay out based on the total number of 2010 road deaths conditional on, say, no change in the drink driving threshold. In market B, you trade similar contracts that pay out on the same outcome, but only if the drink driving limit drops to 0.05. In market C, you trade contracts that pay out at $1 if the drink driving limit drops to 0.05.

    Market C gives you the probability of a change in policy. You use that value to compare the prices in A and B. If the markets figure a 50/50 shot of legislation passing (price of C is $0.5) and the prices in A and B are identical, then the market would be telling you that there's likely no effect of policy on the relevant outcome.

    Unfortunately, opening markets that pay out on things like number of deaths would be more than a little politically unpalatable.

  3. Fantastic post. Witty, urbane and funny.