Do you have a sense of the acceptability rates (i.e. what proportions of the treatment population moderately decreased their meat consumption)? Additionally, how did you account for selection effects (i.e. if a study includes vegetarians, those participants presumably wouldn’t see behaviour change)?
My mental model right now is that some small proportion of Western populations are amenable to meat reductions, with a sharp fall-off after this. Using these techniques on less aware populations might work, but we could assume that most high-income Western populations have already been exposed to these techniques and made up their minds. Averaged over a study, seeing a handful of participants change their minds in moderate ways would show a small effect size, or none at all, depending on the recruited population.
But I know very little about this area, so I assume the above is wrong. I just wanted to know in what ways, and what’s borne out by the data you have.
Most studies in our dataset don’t report these kinds of fine-grained results, but in general my impression from the texts is that the typical study gets a lot of people to change their behavior a little. (In part because if they got people to go vegan I expect they would say that.)
Some studies deliberately exclude vegetarians as part of their recruitment process, but most just draw from whatever population at large. Somewhere between 2 and 5% of people identify as vegetarians (and many of them eat meat sometimes), so I don’t personally worry too much about this curtailing results. A few studies specifically recruit people who are motivated to change their diets and/or help animals, e.g. Cooney (2016) recruited people who wanted to help Mercy for Animals evaluate its materials.
I think this is a fair mental model, but I think one of the main open questions of our paper is about how do we recruit people to cut back on meat in general vs. just cutting back on a few categories, e.g. red and processed meat. So I guess my mental model is that most people have heard that raising cows is bad for the environment and those who are cutting back are substituting partly to plant-based substitutes (reps from Impossible Foods noted at a recent meeting that most of their customers also eat meat) and partly to chicken and fish, e.g. the Mayo Clinic’s page on heart-healthy diets suggests “Lean meat, poultry and fish; low-fat or fat-free dairy products; and eggs are some of the best sources of protein...Fish is healthier than high-fat meats”, although it also says that “Eating plant protein instead of animal protein lowers the amounts of fat and cholesterol you take in.”
So I’d say we still have a lot of open questions...
Do you have a sense of the acceptability rates (i.e. what proportions of the treatment population moderately decreased their meat consumption)? Additionally, how did you account for selection effects (i.e. if a study includes vegetarians, those participants presumably wouldn’t see behaviour change)?
My mental model right now is that some small proportion of Western populations are amenable to meat reductions, with a sharp fall-off after this. Using these techniques on less aware populations might work, but we could assume that most high-income Western populations have already been exposed to these techniques and made up their minds. Averaged over a study, seeing a handful of participants change their minds in moderate ways would show a small effect size, or none at all, depending on the recruited population.
But I know very little about this area, so I assume the above is wrong. I just wanted to know in what ways, and what’s borne out by the data you have.
👋 Great questions!
Most studies in our dataset don’t report these kinds of fine-grained results, but in general my impression from the texts is that the typical study gets a lot of people to change their behavior a little. (In part because if they got people to go vegan I expect they would say that.)
Some studies deliberately exclude vegetarians as part of their recruitment process, but most just draw from whatever population at large. Somewhere between 2 and 5% of people identify as vegetarians (and many of them eat meat sometimes), so I don’t personally worry too much about this curtailing results. A few studies specifically recruit people who are motivated to change their diets and/or help animals, e.g. Cooney (2016) recruited people who wanted to help Mercy for Animals evaluate its materials.
I think this is a fair mental model, but I think one of the main open questions of our paper is about how do we recruit people to cut back on meat in general vs. just cutting back on a few categories, e.g. red and processed meat. So I guess my mental model is that most people have heard that raising cows is bad for the environment and those who are cutting back are substituting partly to plant-based substitutes (reps from Impossible Foods noted at a recent meeting that most of their customers also eat meat) and partly to chicken and fish, e.g. the Mayo Clinic’s page on heart-healthy diets suggests “Lean meat, poultry and fish; low-fat or fat-free dairy products; and eggs are some of the best sources of protein...Fish is healthier than high-fat meats”, although it also says that “Eating plant protein instead of animal protein lowers the amounts of fat and cholesterol you take in.”
So I’d say we still have a lot of open questions...