In Costa Rica, 96% of the scientific journals in the Latindex catalog are published by public universities (LATINDEX, 2023). Additionally, 100% of public university journals are on the diamond route. In Costa Rica, similar to Latin America (Becerril, 2022), journals are financed by publishing institutions, in this case public universities, which has allowed them to remain diamond journals; however, there were no indicators to justify the investment and detect national opportunities for improvement. Due to the above, the need arises to measure the quality of the scientific journals of public universities at the national level, since not all journals apply in selective indexes, which prevents knowing the status of the journals, comparing them with the others and propose actions for improvement.

There is a precedent of an institutional index for the evaluation of scientific journals that has been applied since 2011 at the Universidad de Costa Rica (Córdoba González, Murillo Goussen & Polanco-Cortés, 2016), which functioned as the basis for the proposal of public universities and It has a history of the evaluation results that shows the evolution of the journals (UCR Index, 2023).

Therefore, an index was created to measure the quality of the journals of public universities in Costa Rica. A national index allows us to monitor the quality of our scientific journals so that decisions can be made for the optimization of resources and the sustainability of all of them in Diamand Route. This index evaluates indicators on editorial management, visibility and content. The index evaluation criteria were statistically validated (Polanco et al. 2021).

In the pilot test carried out in 2021, 45 journals were evaluated, which resulted in a normal distribution in the index. In addition to validating the indicators of the index (CONARE, 2023), it allowed obtaining data on the quality of the journals, according to the needs of our country and institutions, giving them closer support to the journals, determining new financing needs for the journals and adequate guidance in decision making.