Literature reviews as standalone papers serve various purposes; these include the development of new theories, the shaping of future research, the production or knowledge dissemination, and support of evidence-based practices. Review papers, as a foundational block of the research process, may promote further research with higher level of quality. However, in some cases, this methodological approach raises questions about their scientific rigor, trustworthiness, systematicity, and transparency. The main goal of this study is to assess transparency levels in previous review papers pertaining to blended learning in higher education. To complete this goal, this study collects and analyzes information about the report of methodological decisions and research activities in 40 review papers. As a result, in this "descriptive review paper," we identify some patterns about the type of reviews and their transparency levels. Findings also demonstrate that most efforts (80%) remain focused on describing a phenomenon in the formats of narrative reviews (65%) and descriptive reviews (15%). These types of papers show low levels of transparency in their reporting process. Nevertheless, trends indicate in the last 5 years an increase in other types of published review papers such as critical, meta-analysis, and qualitative systematic reviews. This represents an important shift in the research domain. Finally, we argue that, regardless of its type, each review paper should have a minimum level of transparency in order to ensure trustworthiness in the research process.