Table 2.

Illustrative quotations for barriers to COVID-19 vaccine acceptability.

Domain	Theme	Quotation (participant number)
Social influences	Receiving strict recommendations	I probably wouldn't agree with [any health-related recommendation] if I was being told that was what was best for me. If somebody is being very strict or rigid about the way that those things are being communicated, then communication is huge. […] I guess if [the COVID-19 vaccine] ever became mandatory, where people had to do it, that would then take away my power to choose. If that ever happened that would be a factor for not getting it. (5) There's a tremendous pressure to accept the vaccine, coming from not only the staff and other inmates, but management as well, because they want to get everything back under normal functionally. I feel that we came to prison because we don't like people telling us what to do in the first place. So when you tell me to do something, my automatic reaction is to say no. (10)
	Believing in conspiracies to harm	I know some countries did not want the type of vaccine that we're going to be getting as inmates. It’s kind of alarming that it's not good enough for some countries, but it's okay for Canadian prison population. (4) There are a lot of conspiracy theorists in here and they wouldn't even bother reading about [the COVID-19 vaccine]. They see it on the news and they go: ‘Ah, that’s just phony, the government is up to something and all the others are trying to inject us with some microchip or something.’ It’s ridiculous stuff that I hear in here. (8) [Other prisoners] said that [governments or authorities] were only giving [the COVID-19 vaccine] to kill people off, to reduce the population in the world. (9)
Belief about consequences	Believing that infection prevention and control measures will not be fully lifted despite vaccination	The vaccine is not going to protect me a hundred percent, right? Why is it then I would take it if I would still have to be just as cautious as I am now about washing and distancing and wearing your masks, etcetera? (1) [The COVID-19 vaccine] is not really for me. It's just not knowing whether we will be able to go into the population. Will we be free, like walking around without a mask on and talking and whatever else? Being sharing stuff with other people, playing cards and whatever else? It's kind of depressing. (9)
	Being concerned with risk of side effects or getting sick because of the vaccine	Now that I'm contaminate-free, I'm more aware, I'm more balanced. I'm better out of drugs. [Concerning the COVID-19 vaccine], why play with fire? There’s nothing wrong with me. So why fix something that ain't broken? (9) It was such a short testing period for the vaccine. So we don't really know if there will be side effects from the vaccine itself. These are my doubts about the vaccine. (7) And I heard a lot of bad things about [the COVID-19 vaccine]. There are some side effects to certain kinds of vaccines and blood clots. Stuff like that really worries me and I know it worries other people too. (14) I worry that I'm going to get sick from [the COVID-19 vaccine]. They say the flu shot has formaldehyde in it. I don't know if formaldehyde is bad to be ingested in small amounts, but I know that we put formaldehyde in dead bodies. So why would I want it in my healthy body? The flu shot can make you sick. I don't know if that's being said about the COVID vaccine, but I wouldn't mind hearing about the reality and the truth of them. (4)
Knowledge	Lacking information on the vaccine	[The information on the vaccine] is not disseminated. It's not packaged properly. And the way that things are in prisons, we hardly receive any information at all. […] I still trust in the science and in public health, but my trust hasn't been waxed and waned a lot because of what's been going on. (10) If there were more facts and more information about where vaccines come from, what methods were used to deem them safe […] and what kinds of people the vaccines were tested on, because people have different immune systems. I think everybody needs to be a little more educated about these things. […] I'm just a little bit skeptic with regards to vaccines, especially if I don't have a high level of information about them. (5)