Table 4 Illustrative quotes related to circumstances in CT that permit or constrain the application of DCTS-tools

The ‘success’ of DCTS-tools depends on individual characteristics of cases and contact persons

“The question is, what can you let people do themselves? I find this a difficult question, because it is very dependent on the specific individual.” PHS-nurse, female, early-30’s.

“I think that PHPs should make an assessment each time: ‘with this person we will use it and with this person we won’t.” PHS-nurse, female, mid-20’s.

DCTS-tools are especially useful when PHS have limited capacity to facilitate ‘traditional’ CT

“The situation in which we were a while ago, that we just couldn’t make it to inform all the contacts… In that kind of situation this [DCTS-tool 2] can be useful.” PHS-nurse, female, late-20’s.

“For me this [all DCTS-tools] is not only to solve the time pressure and capacity issues. I would want this anyway because I think it’s just a lot more efficient. It’s just a new way of how we deal with infections together. So, I think this is something good, also when we do have time.” PHS-nurse, female, early-50’s.

DCTS-tools are less applicable in complex and/or impactful settings in CT

“Maybe someone works at a large business, or with migrants, or at a care facility, or something like this, where you can potentially have a large outbreak. Then you need more control, and you have a lot of factors that are a little bit different than usual, that some digital application cannot consider.” PHS-doctor, female, early-30’s.