# Privacy and Security in Digital Health Contact-Tracing: A Narrative Review
## 3 Results
### Privacy
#### 3.1.2 Privacy Concerns  
Privacy concerns refer to issues people have about how their personal data are collected, used, and shared in the contact-tracing process. Privacy concerns were identified  
Figure 2: Themes derived from paper corpus. as a crucial factor driving the adoption, which acted as a barrier [39,40]. Many studies have reported that privacy concerns were the main reason for not using the contact-tracing app [17-20,22,41-43]. There was a negative relationship between privacy concerns and app usage [44-47]. In several studies, privacy concerns have negatively influenced the intention to use contact-tracing applications as well [42,48,49]. In some studies, the majority of participants had expressed concerns about the privacy and security of personal data [50-52]. Data privacy concerns were strongly associated with adoption intention [46], while app-related privacy concerns had a significant impact on users' intention to adopt contact-tracing apps [53]. Similarly, a European study has reported that information privacy concerns had a significant negative relationship with behavioural intention [54]. Concerns about app information privacy were negatively associated with both the intention to use and attitudes toward contact-tracing apps [55-57]. In line with previous studies, a study in England established that people were less likely to adopt the contact-tracing app if concerned about privacy [58]. In another study in England, among participants who downloaded the contact-tracing app, 47.8% said privacy was extremely important to them [59]. In Ireland, the adoption of digital technology solutions was significantly influenced by privacy and legal concerns related to the use of personal data [60]. In Wales, reluctance to use contact-tracing apps derived from concerns about personal privacy [61]. In New Zealand, suggestions were made that apps should incorporate robust privacy controls for the collected data [62]. In South Africa, some users expressed concerns about the invasion of smartphone privacy, citing a lack of privacy guarantees [63]. In a Twitter analysis, the negative sentiments expressed in India were more focused on privacy issues, while in Brazil they focused more on data misuse [64]. The invasion of privacy is another critical aspect many citizens have raised in their tweets [64]. In a study carried out with registered physicians from the US, UK, and the rest of the world, the majority of respondents (69.8%) believed that potentially relaxing privacy standards to combat the pandemic could result in future privacy violations. In Canada, 17% of users mentioned confidentiality (17%) as a reason for not downloading the app [27]. Notably, respondents willing to install the digital contact-tracing application expressed significantly lower concerns about privacy issues than those unwilling to install the application [65]. Similarly, users were more convinced than non-users that the contact-tracing apps respect users' privacy [66]. Older users were more likely to be influenced by privacy concerns when deciding to disclose information, whereas younger users were not significantly influenced by privacy concerns [67]. A similar finding was recorded in Canada: Privacy concerns related to contact-tracing apps were more prominent in older age groups than in individuals aged 18-29 years [68]. It was reported that a better understanding of safety, security, privacy, and trust plays an essential role in people's willingness to use contact-tracing apps [69]. Some users perceived no assurance of privacy and distrusted the government's guarantees regarding privacy, functionality, and the efforts put into developing the app [63]. Those who did not use the app expressed concerns about privacy violations, and users failed to appreciate the app's privacy-enhancing features. Some believed that the situation demanded that citizens sacrifice privacy (these participants regularly used privacy-invasive apps like Facebook) [70].