Defining the early career researcher: A study of publication-based definitions

Studies of early career researchers need to define and operationalize what qualifies as an early career researcher. Regrettably, consensus on this matter remains elusive, leading to the emergence of diverse approaches in the literature. This study provides an overview of the various ways this concept has been defined and operationalized in previous studies. Four publication-based approaches are identified and tested with the purpose of exploring the possible consequences arising from different publication-based definitions for early career researchers. The four proxies for defining an early career researcher are tested using two samples of authors having published in the fields of library and information science (LIS) and economics. The share of early career researchers seems to be decreasing over time although it depends on the field and definition. The four approaches return quite different results. In LIS, the four different definitions are highly correlated and therefore depict similar pictures over time. This is not the case in Economics, indicating that the choice of approach when defining an early career researcher may have an impact on the results of the analysis in this field. Defining early career researchers through proxies may influence the outcomes of the study, emphasizing the importance of thoughtful consideration when formulating the definition.