Traditionally our analysis has relied on press releases retrieved from a newspaper company-produced database, NikkeiTelecom21. In recent years, however, there has been a notable increase in press releases issued directly by universities, with only a portion included in this database. Our comparative study between NikkeiTelecom21 and the Nikkei Shimbun website revealed that, while the number of press releases in the former has declined since 2019, the latter has maintained a steady output. Furthermore, our investigation of press releases directly collected from the websites of four universities registered with the Science Portal showed substantial variation in their inclusion in Nikkei press releases—for example, while the University of Tokyo had an estimated coverage rate of over 80%, Hokkaido University’s rate was below 15%. This discrepancy points to potential biases in the dissemination of university press releases and highlights the need for broader representation and more comprehensive analysis in understanding how academic research is publicly communicated.