But while the level of trust to ensure data privacy fell from 5.7 out of 10 to 5.49 between May 2020 and August 2021, that remains at a higher point than October 2018, where trust in those institutions rated just 4.78.

That comes from an Australian National University analysis of trust in major institutions to maintain data privacy, which saw that 88 per cent of Australians check in via QR code always or most of the time.

The study of more than 3000 people found confidence in the federal government to maintain data privacy declined to 5.88 out of 10, with figures slightly higher for state and territory governments at 6.07.

Study co-author Professor Nicholas Biddle said significant effort was needed from governments and research institutions to increase trust relating to data privacy.

"That includes adherence to principles of openness and transparency regarding the use of data, disclosure of data breaches, the use of data for the benefits of citizens and customers not for the benefits of organisations and realistic use cases of where data sharing can benefit people," he said.

Respondents indicated trust in social media companies to keep their data private has plummeted more than 10 per cent to just 3.08 out of 10.

Of the institutions analysed, only the Australian Bureau of Statistics saw its trust increase between the studies, jumping from 7.1 to 7.24.

Regarding checking in to venues via QR codes, 62 per cent of those surveyed always scanned, while of those who at least occasionally scan, 32 per cent said it was to keep themself safe and 27 per cent said it was to keep others safe.

For those who checked in less than "always", 58 per cent said they simply forgot to do it.

Further, 7.4 per cent said they don't trust the government with their data, 4.3 per cent said they didn't trust the business and 4.2 per cent don't trust the safety of the apps on their phones.

The study also found Indigenous Australians, those born overseas in a non-English speaking country and people living outside the most advantaged areas were less likely to use check-in apps.

Prof Biddle said the lack of use of check-in apps in these demographics could present a serious challenge.

"The fact ... that many of the factors that influence usage are spatially clustered means that some of these groups are particularly at risk of the negative consequences of an outbreak," he said.

"The fact that these groups are also less likely to be vaccinated only increases that risk."

Australian Associated Press