In which scenario is it likely that a breach of confidentiality could occur?

A breach of confidentiality is most likely to occur when sensitive data is not adequately protected. When a laptop containing sensitive data is stolen, it poses a significant risk because that data can easily fall into the wrong hands. If the information was not encrypted or secured, unauthorized individuals could access personal and confidential information, leading to privacy violations and potentially harmful consequences for the individuals involved in the study.

In contrast, using anonymized data, conducting studies with public data, or choosing not to collect identifiers are strategies that help mitigate the risk of a breach of confidentiality. Anonymized data removes personal identifiers, making it difficult to trace the data back to a specific individual. Public data is generally available and does not require the same level of confidentiality because the information is not private. Additionally, not collecting identifiers ensures there is no way to link participants to their data, which reduces the likelihood of a breach occurring. Thus, the scenario involving the stolen laptop stands out as a situation where confidential information could be compromised.