Objective: Electronic Theses and Dissertations (ETDs) programs have been recognized as a relatively new and effective channel through which information resources can be made available to academics and beyond. This study aims to provide empirical evidence of the impact of ETD programs in the scientific communities. Method: Records containing citations to theses and dissertations (TDs) in Scopus database from 1970 to 2017 are retrieved through a structured query. Trends of the citations of TDs in academic literature in different subject areas are examined. In additions, online search of a random sample of citation records on Google Scholar and BASE provided more insight of the impact of ETD programs, with a focus on open access. Findings: According to the Scopus database, there is an obvious increasing trend in citing TDs in academic literature. In all four broad subject areas, there is an increasing trend in citing TDs, in particular from 1996 onward. The analysis of the random sample and the survey provide complementary elements for a better understanding of this trend, of the role of ETD programs and of the impact of accessibility via institutional repositories.