Minimum pricing modellers eat humble pie

Needless to say, I had the last laugh

This study was published yesterday and got no attention whatsoever from the media despite it being written by a team in Sheffield who used to get blanket coverage for their every pronouncement. What changed? Well, they used to produce models showing that minimum alcohol pricing would work and now they’ve produced a study showing that their model didn’t work.

The results above suggest the introduction of MUP in Scotland did not lead to a decline in the proportion of adult drinkers consuming alcohol at harmful levels. It also did not lead to any change in the types of alcoholic beverage consumed by this group, their drinking patterns, the extent to which they consumed alcohol while on their own or the prevalence of harmful drinking in key subgroups.

Oof! So much for the ‘exquisitely targeted’ policy of minimum pricing being an ‘almost perfect alcohol policy because it targets cheap booze bought by very heavy drinkers’.

After building your entire reputation on modelling minimum pricing, it must have been painful for them to write this…

... the lack of evidence for a decline in the prevalence of harmful drinking arising from MUP is contrary to model-based evidence that informed the introduction of the policy.

Hey-ho. I guess the model was garbage, as I said from that start. Never mind. It’s only cost drinkers in Scotland a few hundred million pounds. Will the Supreme Court be taking another look at that court case that was won off the back of an incorrect model?

The lack of change in the prevalence of harmful drinking may arise for several reasons. First, people drinking at harmful levels may be less responsive to price changes than lighter drinkers. 

You don’t say! If only someone had mentioned this earlier!

Previous qualitative research and studies of purchasing behaviour among people with alcohol dependence (i.e. a group that comprises approximately 20% of those drinking harmfully in the United Kingdom and thus 1% of the overall population) supports this view. However, the very large price increases imposed by MUP on people drinking harmfully, their inability to switch to cheaper products and clear evidence of successful policy implementation and compliance, mean their price responsiveness would need to be extremely low to negate any impact on consumption.

But it is extremely low! I explained this over a decade ago when I took the model to task for making the plainly daft assumption that heavy drinkers are more price sensitive than moderate drinkers. I wrote:

“The model assumes that minimum pricing will have more effect on the consumption patterns of heavy drinkers than on moderate drinkers because heavy drinkers are more price-sensitive. This is a convenient belief since it is heavy drinkers who cause and suffer the most alcohol-related harm, but can we really assume that someone with an alcohol dependency is more likely to be deterred by price rises than a more casual consumer? The SAPM model says that they are, and yet there is ample evidence to support the common sense view that heavy drinkers and alcoholics are less price-sensitive than the general population (eg. Gallet, 2007; Wagenaar, 2009). Indeed, research has shown that price elasticity for the heaviest drinkers is “not significantly different from zero”—they will, in other words, purchase alcohol at almost any cost.”

You don’t need an encyclopaedic knowledge of the price elasticity literature to work this out. For most people, it falls under the umbrella of the bleeding obvious. Here we are 11 years later and the penny still hasn’t quite dropped at Sheffield, but we’re getting closer.

And here come the excuses…

…the current MUP may be set too low to generate detectable impacts. The £0.50 was initially proposed circa 2011 and would have affected approximately 70% of off-trade alcohol units sold at that time compared with 44% in 2018 when the policy was introduced.

This is the old ‘the medicine isn’t working, more medicine’ routine and they’re not wriggling out of it that easily. In 2011, the price being talked about was 40p or 45p. They were still modelling 45p as their base case in 2014 and in 2016 they projected that a 50p price would ‘reduce consumption of harmful drinkers in poverty by 681 units per year on average compared to 181 units per year for harmful drinkers not in poverty.’ You can’t blame 18 months’ moderate inflation for the failure of that to happen.

To be fair, they admit that.

Although this weakens the effectiveness of the policy, it is not sufficient to explain the null results identified here because those drinking harmfully still faced significant price increases.

Their only remaining cope is that although they didn’t find any impact on people drinking at harmful levels (35+ units a week for women and 50+ units for men), they found a 3.5% reduction in consumption among people drinking at ‘hazardous’ levels (14−35 units a week for women and 14–50 units for men). But in practice these are fairly moderate levels of consumption that are unlikely to do you any harm and the threshold only starts at 14 units because of some ultra-dodgy modelling conducted by (you guessed it) the Sheffield Alcohol Research Group when the Chief Medical Officer was rigging the guidelines.

This is yet more evidence that minimum pricing has failed. All the evaluation studies have found a trivial reduction in alcohol consumption across the population and no reduction - or even an increase - among the heaviest 5% of drinkers who were supposed to be most affected by the policy. There was no impact on A & E attendances, hospital admissions or crime and, with the exception of one questionable retrospective modelling study, there was no impact on mortality.

I suppose it would be unusual in an academic study, but it would have been a nice touch if the authors said ‘we’re sorry’ in the conclusion.