Scientific impact of researchers: contribution vs h-index?

Abstract

In recent years, the use of impact indexes by institutions to evaluate scientific journals, the productivity of institutions, or researchers, has increased. This article discusses the validity of the use of these indicators to assess the academic trajectory of researchers. The most widely used indicator to evaluate researchers is the h-index, which is based on the number of articles cited at least a minimum number of times h. This index does not consider the production that is below that value, the impact or individual contribution of the researcher, the author’s positions in the articles, the time during which those articles were published, the subject area, or the time that some articles require in some topics to effectively impact at the level of the scientific community. Einstein's citation profile and Watson and Crick's (1953) article describing the DNA double helix are used as examples showing that the greatest impact may not be immediate and may require years of development in the scientific area, despite that its importance was key to its development. The indices are ways of quantifying impacts, but their use and abuse, and especially their use to consider aspects that are not what they measure, can lead to wrong conclusions. Although they are part of the tools available to measure scientific productivity, they must be considered based on what they measure based on the inputs and criteria on which they are based. Therefore, it is important that scientific evaluation systems put them in context when considering them for the evaluation of academic performance.