The personalised outreach mentioned just means that the respondents were initially sent a stock email and then when they didn’t respond, they were sent a more personalised message. It doesn’t meant that the surveyors emailed their friends. The survey was based on mass outreach from a list from professional societies
Snowballing contacts does introduce a risk of bias but that is mitigated by the disciplinary and geographic spread in the target sample. Respondents in non developed countries gave a higher chance of zoonosis, so the prospect that the survey was biased because it was sent to eg Kristian andersen who then recommended people who knew favoured his opinion seems low.
It is true that the survey showed low familiarity with the relevant literature. First, this is an interesting finding in itself. Second, in many expert polls the field experts may not have read much of the literature on some specific question.eg this is likely true of the igm poll of economists, which is nevertheless useful.
Competing claims have been made about what virologists in general actually think about this topic. We now have some information on this
Snowballing contacts does introduce a risk of bias but that is mitigated by the disciplinary and geographic spread in the target sample.
Is there any chance you guys could share information about the trees of who recommended who, to help get a sense of how big this bias could be? Like, how large was the largest recommendation chain, what fraction of people were recommended vs initially contacted, etc?
There were six people of 168 respondents who came via people some of the authors already knew or snowballing. I don’t think this would have much effect on the overall picture of the results
The personalised outreach mentioned just means that the respondents were initially sent a stock email and then when they didn’t respond, they were sent a more personalised message. It doesn’t meant that the surveyors emailed their friends. The survey was based on mass outreach from a list from professional societies
Snowballing contacts does introduce a risk of bias but that is mitigated by the disciplinary and geographic spread in the target sample. Respondents in non developed countries gave a higher chance of zoonosis, so the prospect that the survey was biased because it was sent to eg Kristian andersen who then recommended people who knew favoured his opinion seems low.
It is true that the survey showed low familiarity with the relevant literature. First, this is an interesting finding in itself. Second, in many expert polls the field experts may not have read much of the literature on some specific question.eg this is likely true of the igm poll of economists, which is nevertheless useful.
Competing claims have been made about what virologists in general actually think about this topic. We now have some information on this
(Casual readers may not realize that John Halstead was one of the co-authors of the report on this survey)
Is there any chance you guys could share information about the trees of who recommended who, to help get a sense of how big this bias could be? Like, how large was the largest recommendation chain, what fraction of people were recommended vs initially contacted, etc?
There were six people of 168 respondents who came via people some of the authors already knew or snowballing. I don’t think this would have much effect on the overall picture of the results
Correction my apologies. Apparently 30 respondents were snowballed from 17 others. We’ll look into how this affects the results
Thanks!