What key factor influenced the IRB's determination that the researcher’s activity does not constitute research with human subjects?

The determination that the researcher’s activity does not constitute research with human subjects hinges largely on the nature of the data being utilized. In this scenario, the critical factor is that the data is publicly available and lacks identifiers. When data is publicly available, it means that it can be accessed by anyone and does not contain personal information that can be linked to individuals. This absence of identifiers ensures that the individuals involved cannot be easily identified, thereby mitigating the ethical considerations typically associated with research involving human subjects.

When research uses identifiable data, it poses higher risks concerning privacy and confidentiality, prompting more stringent oversight by an Institutional Review Board (IRB). However, if the data is completely de-identified and available to the public, the ethical burden decreases because there are fewer risks to the individuals whose data is being analyzed. Hence, this aligns with the IRB's framework whereby research that does not implicate the rights or welfare of individuals is often exempt from oversight.

This answer effectively illustrates why the situation described does not conform to the typical definition of human subjects research. The other factors mentioned, such as interaction with subjects or participation in data collection, indicate a level of engagement with individuals that inherently raises ethical concerns, which are not present when only publicly available and de-identified