Peruvian contributions to scientific publications on experimental research against COVID-19: a systematic review

Study protocol

The present systematic review was carried out as per the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).²² The protocol for this systematic review was registered on INPLASY (INPLASY202340080) and is available in full at inplasy.com. The systematic review has been elaborated according to PRISMA 2020 checklist (see Reporting guidelines).²²

Search strategy

The search was limited to studies published from December 2019 to June 22, 2022, in the PubMed database (Last accessed on 22 June 2022), with free electronic access that contains more than 35 million citations and abstracts of biomedical literature that includes various literature resources of the National Library of Medicine (NML) such as MEDLINE, PMC, and other databases.²³ The search for the terms associated in the literature with COVID-19 and Peru was carried out using the MeSH term (Medical Subject Heading), and the results were analyzed in a co-occurrence network map of MeSH terms in the VOSviewer software (version 1.6.18).²⁴ MeSH terms, which are used to index the citations since this is a vocabulary controlled by the NML, organize their descriptors hierarchically so that more specific articles can be found from a broad search. Specialists from various areas constantly update the MESH term; every year, new concepts are modified and added.^25,26 The search string used in PubMed was: ((COVID-19[MeSH Terms]) OR (SARS-CoV-2 [MeSH Terms])) AND (PERU).

Selection criteria and data extraction

The studies included in the systematic review were selected in three stages. First, duplicate articles, original articles other than the English language, critical and systematic reviews, meta-analyses, and publications other than an original article were excluded: letters to the editor, commentary, editorial and case reports, data studies, news, conference, and directory; all these classifications were considered using the PubMed filters.^27–29 Secondly, the titles and abstracts of the studies selected using the search strategy were analyzed. Finally, complete papers that might be relevant were located and separated from journals whose titles or abstracts lacked the pertinent information to be taken into account in the systematic review. The included studies were those that were published in journals of quartile one or two, had first authors and/or corresponding authors with Peruvian institutional affiliations, and/or had Peruvian funding. The research topics for these studies had to produce new scientific knowledge, development, innovation, and/or adaptation of new or improved low-cost technologies, products, mechanisms, or services.^30,31

Data extraction was performed by K.C.-M. and validated independently by M.A.C.-P., with discrepancies resolved through discussion and by conferring with M.A.C.-F. The following data were extracted: first author, first author’s institution of affiliation, first author’s country, corresponding author, corresponding author’s affiliation, corresponding author’s country, journal, year of publication, quartile, impact factor, institution funder, research topic, type of biomedical research, and study applicability. The quartiles and impact factors of the journals were obtained from the Scimago Journal and Country Rank and/or on the main pages of each journal, respectively. The classification by type of biomedical research was carried out considering basic research (animal experiments, cellular studies, biochemical, genetic, and physiological research, and studies on the properties of drugs and materials) and applied research or clinical studies (interventional studies (or experimental) and non-interventional (or observational), criteria established by Röhrig, B. et al. 2009.³² Furthermore, according to the applicability of the study, they were classified into two types of research: basic and applied. Basic research aims to explain phenomena by obtaining information and applied research seeks to provide a concrete practical application, that is, to solve a specific problem. These criteria were taken from CONCYTEC of Peru.

Data sources and study selection

A thorough analysis of Peru’s experimental scientific research on COVID-19 was carried out in the current paper. The study strategy’s flowchart was created and displayed (Figure 1). To do this, a search was conducted in the PubMed database using the search mentioned above string of MeSH terms, and a network map of the co-occurrence of MeSH terms was created (Figure 2). Through the search, 794 scientific papers between December 2019 and June 22, 2022, were found. A network map was created using 2,390 keywords, of which 212 achieved thresholds, and the minimum number of keyword occurrences was set at five. The most frequently occurring keywords were “COVID-19” (935 occurrences; total link strength: 7,327) and “HUMANS” (788 occurrences). The size of the nodes shows how frequently they occur. The co-occurrence of the nodes is shown by the curves connecting them in the same publication. The frequency of co-occurrences of two keywords increases with decreasing distance between nodes; in this case, the most frequent terms, such as “COVID-19”, “HUMANS”, “SARS-COV-2”, “PANDEMICS”, and “PERU”, are observed (Figure 2). Nine studies on experimental scientific research on COVID-19 were selected (Figure 1). Data such as PMID, research types, the applicability of the study, theme, specific theme, year, and journal were taken out of the chosen studies (Table 1).

Figure 1. Systematic review Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram of the study selection process.

Figure 2. Selected articles using the PubMed database relating to COVID-19 and Peru.

A) Network map built by VOSviewer based on the co-occurrence of MeSH terms. B) Red cluster zoom related to COVID-19 and Peru. C) Word cloud based on the Keywords.

Type of biomedical research and study applicability

Biomedical research generally encompasses basic and clinical research also called applied research, specifically observational diagnostic studies and experimental studies.^33,34 The basic biomedical research category, comprising 55.6% (n = 5)^35–39 of the total studies considered in the review, came in first position as the category with the most original publications. On the other hand, clinical observation diagnoses accounted for 44.4 % (n = 4)^40–43 of the total number of original articles and was the second type of biomedical research with the highest number of unique publications. Of these, 11.1% (n = 1) of the total original articles of the review were classified as “Experimental” clinical research, specifically a preclinical study, and 33.3% (n = 3) of the total original articles of the review were classified as “Diagnostic Observational” clinical research (Table 1).

Two categories of research—basic and applied—were separated based on inquiry. Basic research seeks to understand phenomena by gathering data, whereas applied research’s major goal is to provide an accurate, practical application, or to address a particular issue.^30,31 The systematic review results were classified according to their applicability, of which the most prevalent was “Applied” research with 77.8% (n = 7) of the total original articles of the review. On the other hand, the one with the lowest prevalence was “Basic” research with 22.2% (n = 2) of the total original articles of the systematic review (Table 1).

Thematic area and specific thematic

The calls for funding, “Special Projects: Response to COVID-19” and “Special Projects: Modality Emerging Needs to COVID-19 2020-02,” both sponsored by CONCYTEC in response to the national emergency of COVID-19, were used to trace general and specific categories for the studies of the systematic review.^30,31 The first place was taken by the thematic area of “Treatment and transmission,” which accounted for 55.6% (n = 5) of the total original articles. The second place went to the thematic area of “Diagnosis,” which accounted for 33.3% (n = 3) of the total studies, while the third and final place went to the thematic area of “Sanitary accessories,” which accounted for 11.1% (n = 1) of the total studies. Study of molecules and potential applications for SARS-CoV-2 was the specific theme that predominated, accounting for 33.3% (n = 3) of all original articles, followed by “Studies of virus transmission mechanisms to reduce its spread,” accounting for 22.2% (n = 2) of original articles. Both specific themes fall under the treatment and transmission thematic area. However, “Diagnosis” was the next most prevalent theme, with “Adaptations of diagnostic tests” accounting for 11.1% (n = 1) of the total number of original articles, “Rapid diagnosis methodology” coming in second with 11.1% (n = 1), and “Tests laboratory” coming in third with 11.1% (n = 1) of the total number of original articles (Table 1). Finally, the specific theme with the lowest number of original articles was “Sanitary accessories”, having only one specific subject and one original article “Respirators and ventilators” with 11.1% (n = 1) of the total original articles of the review (Table 1).

Journal impact factor and quartile

A first quartile (Q1) journal has a high impact factor and number of citations in a specific thematic area, allowing greater visibility of published articles.^44,45 The authors managed to publish in Scientific Reports and PLOS One most often (n = 2; 22.2%), whereas only one original paper (11.1%) was published in each of the other five journals. One journal from the United Kingdom, two from the United States, and four from Switzerland made up the total number of journals in the systematic review research. Seven journals came from the first quartile (Q1). The highest impact factors were 20.693, 6.429, and 6.208, representing the Journal of Medical Virology, Frontiers in Immunology, and International Journal of Molecular Sciences in first, second, and third position, respectively. The fourth- and fifth-placed journals were Scientific Reports with an impact factor of 4,996 and Molecules with 4,927. Finally, Frontiers in Cellular and Infection Microbiology and PLOS One impact factors of 4,300 and 3.240, respectively, were sixth and seventh in the ranking as the journals with the highest impact factor (Table 2).

Funding and grants

Only one (11.1%) of the included articles was jointly funded by Peru and the United States. The organizations that funded the most original articles were the National Health Institute (INS), CONCYTEC, and Universidad Católica de Santa Maria representing 22.2% (n = 2) of total included articles. The country that financed the largest number of original studies was Peru, with 88.9% (n = 8) of the total articles. Co-financing for one study (11.1%) in the systematic review came from INS and CONCYTEC, “Universidad Católica de Santa Mara” and “US Grants” jointly funded one study (11.1%) and CONCYTEC and Universidad San Juan Bautista jointly funded one study (11.1%). Only two universities in Peru—Universidad Católica de Santa Mara and Universidad San Juan Bautista—funded articles included in the systematic review (Table 3).

Affiliation of the first author

Meanwhile, Universidad Católica de Santa Mara, Universidad Cayetano Heredia, and FARVET SAC are tied for second position with 22.2% each (n = 2). The institutions with the lowest production of original papers from the included studies were Harvard Medical School, Massachusetts General Hospital, and Pontificia Universidad Católica del Peru, all of which produced 11.11% (n = 1) of all the systematic review’s original publications (Table 4). Regarding the institution with the highest production of original articles of the systematic review based on the affiliation of the first author. Universidad Católica de Santa María and INS occupy the first place, each with 33.3% (n = 3), followed by the Universidad Peruana Cayetano Heredia, Pontificia Universidad Católica del Perú and Farmacológicos Veterinarios SAC (FARVET SAC), all of them with 11.1% (n = 1). The results showed that all the original articles produced by the “Universidad Católica de Santa María” (n = 3) belonged to the thematic “Treatment and transmission”. Similarly, “Diagnosis” was the theme shared by all the original papers produced by INS (n = 3). Universidad Peruana Cayetano Heredia and FARVET SAC, on the other hand, both published articles on the “Treatment and transmission” theme. Finally, Pontificia Universidad Católica del Peru published an article with the theme “Sanitary accessories”. Based on the affiliation of the first author, Lima, Peru, produced the most original articles, accounting for 55.6% (n = 5) of the total; Arequipa, Peru, produced 33.3% (n = 3) of the total; and the city of Cusco, Peru produced the least original articles. The city of Chincha accounted for 11.1% (n = 1) of all originals (Table 5).

Affiliation of the correspondence author

Most of the corresponding authors of the included articles were affiliated in “Peru”, accounting for 88.9% (n = 8) of the total. The United States was second with 11.1% (n = 1). The city of Lima accounted for 44.4% (n = 5) of the corresponding authors’ affiliations in Peru, followed by Arequipa and Chincha with 22.2% (n = 2) each. Most corresponding authors were affiliated with INS (33.3%; n = 3). Two of these articles list INS as the sole affiliation of the corresponding author, while the third includes both INS and Universidad San Juan Bautista. The Universidad Católica de Santa Maria, Universidad Cayetano Heredia, and FARVET SAC, each had two corresponding authors (22%; n = 2). Finally, Harvard Medical School, Massachusetts General Hospital, and Pontificia Universidad Católica del Peru are the organizations that produced the fewest included articles in the systematic review, accounting for a combined 11.11% (n = 1) of all the systematic review’s articles (Table 5).