Bibliometric Analysis of Acta Stomatologica Croatica: 2009-2018.

OBJECTIVE: To analyze a bibliometric profile of scientific production published in Acta Stomatologica Croatica (ASCRO).
MATERIAL AND METHODS: Scientific papers published from March 2009 to December 2018 were analyzed. Information on the year of publication was collected by four trained examiners. Dentistry area, study type and design, data analysis method, presence of randomization, number of authors and corresponding author affiliation were investigated. Data were analyzed using descriptive statistics.
RESULTS: A total of 328 articles were evaluated, with a predominance of research in the field of Dental Materials (16.5%), with original article being the most frequent (74.1%). Observational studies accounted for 52.4%, using inferential statistics (83.2%) and non-randomized experimental studies (66.1%). Cross-sectional studies were more common in areas of Behavioral, Epidemiologic & Health Services Research (86.3%), case reports in Craniofacial Biology (54.0%) and Oral Health Research (53.1%), while in vitro studies were more common in the areas of Dental Materials (90.7%), Microbiology / Immunology (70.0%) and Cariology Research (66.7%). Most articles were written by four authors (24.1%), while foreign affiliation was observed in 53.0% of studies.
CONCLUSION: The profile of ASCRO scientific production shows a predominance of original studies carried out in the areas of Dental Materials and Behavioral, Epidemiologic & Health Services Research, with growing participation of foreign researchers.

Introduction

Research is an investigative process used to increase or reassess current knowledge. The evolution of knowledge in a given area allows the development of not only important scientific and technological advances, but also generates great implications, both in the health and social spheres ().

The way in which knowledge is constructed and disseminated is of paramount importance, since it will influence and guide thoughts, reflections and attitudes, shaping actions in all fields of knowledge (). In the health sciences, the dissemination of new knowledge is firstly performed through scientific journals, specialized in the publication of original information and elaborated as research articles that have the ultimate goal of improving professional practice ().

The search for the best scientific evidence in clinical decision-making in Dentistry has gained attention in recent years (), with bibliometric analysis being an important tool that measures the level of development of a specific scientific field (). Bibliometrics is a systematic method for evaluating research results, and it can help map the changes in a scientific community over time (), since the information contained in this study type becomes a reference for future studies, which can focus on the type and quality of evidence published in dental journals ().

The scientific journal Acta Stomatologica Croatica (ASCRO) was set up by the School of Dental Medicine of Zagreb and the Croatian Dental Society of the Croatian Medical Association, being continuously published since 1966, in a volume with four annual editions, with volume 7 being the only exception, published in 1972/73 (). The journal is indexed in Pub Med Central, Chemical Abstracts, Directory of Open Access Journals, EBSCO and Scopus. Currently, articles are bilingual, in Croatian and English, making the journal more accessible to the world scientific community. ASCRO publishes editorials, original scientific articles, preliminary communications, reviews, professional articles and case reports, along with conference abstracts, professional information of interest, historical and memorial views ().

ASCRO occupies the seventh place, according to the number of readers among journals in the area of Biomedicine and Health in Croatia (). Thus, the aim of this study was to analyze the bibliometric profile of the scientific production published in Acta Stomatologica Croatica.

Material and methods

This is a descriptive research dealing with articles published in ASCRO from March 2009 to December 2018. Data were collected from the journal's website (http://www.ascro.hr/) and ten volumes were analyzed, with four annual editions (quarterly periodicity), totaling 40 issues.

Inclusion criteria were: selection of original research articles, which included preliminary communications and professional articles, literature review articles and case reports. Book reviews, reports of congresses and professional meetings, as well as summaries of congresses, editorials and letters to the editor were excluded.

Data collection was independently performed by four trained examiners. Information regarding the year of publication; area of Dentistry according to the International Association for Dental Research (IADR) (); study type (original scientific article, review article and case report); study design (experimental, observational and documentary); data analysis method (descriptive and analytical); the presence of randomization (yes or no); number of authors and corresponding author affiliation (Croatian or foreign) were recorded.

Initially, the abstract of each publication was analyzed and on occasions when this analysis was not sufficient for data extraction, the article was fully read. When there was disagreement in the categorization, the decision was obtained by consensus among examiners.

Data were recorded on a form standardized in Microsoft Office Excel 2016 (Microsoft Press, Redmond, WA, USA) and analyzed using the IBM SPSS software (version 22.0 for Windows, IBM Corp., Armonk, NY, USA). A descriptive analysis was performed for categorical variables and measures of central tendency and variability for quantitative variables.

Results

In the evaluation period, 328 articles were published, corresponding to an average of 32.8 papers / year, with a minimum of 28 and a maximum of 38 publications / year. Of these, 11.6% were published in 2018, followed by years 2015 and 2016, both with 11.0%. Years 2012 and 2014 had the lowest percentage of scientific productions, with 8.5% each (Figure 1).

Figure 1

Number of articles published in ASCRO according to year.

The predominant areas of Dentistry in studies were Dental Materials (16.5%), followed by Behavioral, Epidemiologic & Health Services Research (15.5%) and Craniofacial Biology (11.3%). In contrast, the areas of least representation were Evidence-Based Dentistry with 0.6% and Woman in Science with only 0.3% of articles (Figure 2). No studies in the areas of Network for Practice-Based Research, Neuroscience and Nutrition Research were found.

Figure 2

Distribution of articles according to the area of ​​Dentistry.

Regarding the characteristics of studies, there was a predominance of original articles (74.1%), observational studies (52.4%), analytical data analysis method (83.2%) and most experimental studies were not randomized (66.1%) (Table 1). Regarding the design of observational studies, 75 were cross-sectional, 73 were case reports, 22 control cases, 1 cohort and 1 case series. Clinical trials comprised 33, experimental in vitro comprised 78, in vivo comprised 2 and in vitro and in vivo comprised 1. Of documentary studies, only two of them were systematic reviews.

Table 1

Distribution of articles according to the characteristics of studies.

Variables	N	%
Article type
Original scientific article	243	74.1
Review article	12	3.6
Case report	73	22.3
Study design
Observational	172	52.4
Experimental	114	34.8
Documentary	42	12.8
Data analysis method
Descriptive	41	16.8
Analytical	203	83.2
Presence of randomization
Yes	39	34.2
No	75	65.8

Cross-sectional studies stood out as the design most frequently used in the area of Behavioral, Epidemiologic & Health Services Research (86.3%). Case reports represented the study type most used in the area of Craniofacial Biology (54.0%) and Oral Health Research (53.1%), and in vitro studies, in turn, in Dental Materials (90.7%), Microbiology / Immunology (70.0%) and Cariology Research (66.7%) (Table 2).

Table 2

Distribution of study designs according to area of ​​Dentistry.

ÁREA DA ODONTOLOGIA	Design
Cr SecN	Case CtN	COHN	Case RepN	Case SerN	IN VITN	IN VIVN	IN VIT IN VIVN	Clin TrN	DOCN	LRN	SRN	TOTALN
Oral Health Research	4	2	0	17	0	2	1	1	2	1	2	0	32
Behavioral, Epidemiologic & Health Services Research	44	1	0	0	0	0	0	0	2	4	0	0	51
Periodontal Research	4	6	0	5	0	2	0	0	4	0	2	0	23
Salivary Research	0	2	0	0	0	2	0	0	4	0	1	0	9
Pediatric Oral Health Research	4	2	0	10	0	0	0	0	0	1	1	0	18
Mineralized Tissue	1	0	0	1	0	4	0	0	0	0	1	0	7
Prosthodontics	6	0	0	7	0	0	0	0	2	4	1	0	20
Orthodontics Research	2	2	0	0	0	1	0	0	0	3	0	0	8
International Network for Orofacial Pain and Related Disorders Methodology	1	3	0	2	0	1	0	0	2	0	1	0	10
Dental Anesthesiology Research	0	0	0	1	0	0	0	0	3	0	0	0	4
Pulp Biology and Regeneration	0	0	0	3	0	5	1	0	1	0	1	0	11
Craniofacial Biology	4	2	0	20	1	0	0	0	2	5	2	1	37
Implantology	0	1	0	3	0	0	0	0	6	0	1	0	11
Dental Materials	1	0	0	0	0	49	0	0	2	1	0	1	54
Cariology Research	1	0	0	0	0	4	0	0	0	1	0	0	6
Education Research	1	0	0	0	0	0	0	0	0	5	1	0	7
Geriatric Oral Research	1	0	0	2	0	0	0	0	0	0	0	0	3
Microbiology/Immunology	0	1	0	0	0	7	0	0	2	0	0	0	10
Woman in science	0	0	1	0	0	0	0	0	0	0	0	0	1
Diagnostic Sciences	0	0	0	2	0	1	0	0	0	1	0	0	4
Evidence based Dentistry	1	0	0	0	0	0	0	0	1	0	0	0	2

Cr Sec = Cross-Sectional; Case Ct = Case Control; COH = Cohort; Case Rep = Case Report; Cas Ser = Case Series; IN VIT = In vitro; IN VIV = In vivo; IN VIT IN VIV = In vitro and In vivo; Clin Tr = Clinical Trial; DOC = Documentary; LR = Literature Review; SR = Systematic Review.

Regarding authorship, the 328 articles included a total of 1407 authors, with an average of 4.29 ± 1.75 author / article, median of 4.00, minimum of 1 and maximum of 10 authors. There was a greater number of articles with four authors (24.1%) (Figure 3).

Figure 3

Distribution of articles according to number of authors.

As for the corresponding author affiliation, there was a higher frequency of publications of foreign origin (53.0%). Foreign studies were carried out in Brazil (25.9%), Turkey (12.1%), Greece (10.9%), India (9.8%), Bosnia (7.5%), Thailand (4.0%), Spain (4.0%), Kosovo (3.4%), Germany (2.9%), Italy (2.9%), Malaysia (2.3%), Saudi Arabia (2.3%), in Serbia (1.1%), the United States of America (1.1%). Other countries such as Poland, Bulgaria, Switzerland, Romania, Pakistan, Nigeria, Holland, Scotland, North Macedonia, Israel, Portugal, Slovenia, Libya, England, Albania, Sudan and Colombia accounted for 0.6% each.

Discussion

The strategy most used for the dissemination of research results is the publication of articles in scientific journals (). There is significant growth in the dental literature for most bibliometric indices (), and bibliometric analysis is capable of describing how a given scientific field is evolving, thus helping researchers to identify changing research focuses, as well as knowledge gaps ().

A previous study involving the ASCRO bibliometric analysis from 1987 to 2006 revealed an average of 35.6 articles per year (). It was found in this study that the scientific production of the journal during the analyzed period increased considerably. The following can be considered as possible reasons related to this result: significant changes in ASCRO over these 10 years such as indexation in Scopus (Elsevier) in 2009; the creation of a website, enabling the access of the scientific community to the journal at any time and any place; the inclusion in the Cross Ref system and the adoption of its own DOI number (Digital Object Identifier), in 2014, making documents permanently available (); indexation in Pub Med Central (PMC), which increased its visibility in 2016; and inclusion in the ESCI (Emerging Sources Citation Index), which is an integral part of the Web of Science Core Collection (Clarivate Analytics), in 2018 ().

These changes in ASCRO affected its visibility and a gradual increase in the number of published articles confirms the quality of the journal, which is well accepted by researchers and professionals and has consolidated editorial policy, receiving support from the School of Dental Medicine of Zagreb, the Croatian Medical Association and the Ministry of Science, Education and Sports (). Currently, the demand to “publish or perish” in the academic community may also have driven the increase in dental productivity ().

The most frequently studied areas of Dentistry were Dental Materials and Behavioral, Epidemiologic & Health Services Research. The science that involves dental materials aims to explore and develop biomaterials that will be used in the oral cavity (). This greater focus on the area of dental materials may be related to high competition among technological innovation companies, mainly in the field of nanotechnology, which has promoted rapid progress in the area of biomaterials, providing the development of new materials and devices for biomedical applications, in addition to greater knowledge about the interaction between biomaterials and biological tissues (). New materials have been daily launched and the application of dental biomaterials on gingival, mucous and hard tissues may constitute a risk if the professional does not master the characteristics, concentrations and inherent properties of materials (). In this context, advances in the area allow dentists to use innovative therapies, restoring the physical, psychological and social well-being of patients.

In this research, the area of Epidemiology showed significant representativeness. Despite being a relatively new field, the study of Epidemiology was stimulated by the growing concern with public health (). These studies are important because they seek to identify the causes of a disease in order to deepen the understanding and improve population's health through numerous applications in the field of public health related to the planning and evaluation of health services ().

However, there are areas which are not sufficiently explored, such as Evidence-Based Dentistry and Woman in Science, which is a gap in scientific knowledge. Thus, greater incentive to research and dissemination of scientific production in these areas is necessary in order to increase the journal's impact.

Most published articles were cross-sectional studies that presented limitations as to the fact that they are performed at a certain time, which did not allow inferring causality (). However, they are quick and had low cost to estimate the prevalence of oral health problems, identify treatment and serve as source of planning and organization for public oral health policies ().

In vitro studies accounted for the majority of experimental research, but although they are necessary, as they precede research on human beings, they are not able to determine or there is a limitation for determining the clinical effect of experiments, and they often become repetitive due to the high number of surveys (, ).

The pyramid of scientific evidence determines the hierarchy or levels of evidence in its structure. These levels are organized in ascending order of internal validity, with randomized clinical trials, systematic reviews and meta-analyses representing the highest level of evidence available (). A small number of clinical trials and systematic reviews were observed in the present research, a fact that may be associated with the difficulty of their execution, since these are studies that require more time and cost, requiring greater experience for their execution, as well as a research group well prepared for their development ().

It could be expected that the number of well-conducted clinical trials will be even lower, considering criteria related to the randomization of experimental groups, since most experimental studies found were not randomized. Therefore, it is necessary to encourage researchers to publish the gold standard study types for an evidence-based practice.

ASCRO's bibliometric analysis in the 1987-2006 period showed that 711 articles were written by 1136 authors, corresponding to 3.3 authors / article (). In the present study, the average number of authors / article was 4.29. A recent study carried out with Brazilian researchers with notorious scientific production indicated that they consider four the ideal number of co-authors to enhance scientific production (). Collaboration among authors makes research more visible, since co-authors add their scientific knowledge, enabling deeper evaluations, which, consequently, create more favorable conditions for the production of high-quality works ().

Regarding the corresponding author affiliation, there was a prevalence of publications of foreign origin and, among these, there was a predominance of Brazilian researchers. Over the years, Brazil has grown considerably in the field of scientific production. According to data from SC Imago Journal and Country Rank, the country ranks 2nd position, with most international articles published in Dentistry (). The increase in the number of scientific publications by Brazilian researchers reflects the role of incentives implemented by Brazilian funding agencies, with emphasis on the development of national graduate programs and the granting of research productivity grants by CNPq (National Council for Scientific and Technological Development), as a way of motivating researchers ().

A high number of studies of foreign origin may indicate the journal's visibility worldwide. Free access to the journal through the Portal of Scientific Journals of the Republic of Croatia (Hrčak), a central portal that brings together Croatian scientific and professional journals that offer open access, as well as the publication of the online version of the journal and the digitization of the entire collection since the first year has increased the interest of researchers in publications, increasing the relevance of ASCRO in the scientific community and allowing the increase in the number of authors in its editions (). Indexing in global databases has also expanded the journal's worldwide relevance (); another factor is that there are no fees for submission or publication of articles.

According to Borić and Štefić (), the use of Cross-ref Similarity Check, software that facilitates the recognition of articles that contain plagiarized data will also raise the standard of acceptance of articles and will have a high impact on the future of the journal.

It is important to highlight the fact, which is a limitation of the present article, that this study considers the corresponding author as a way of identifying the institutional affiliation of authors, consequently, some studies may have been inadequately categorized, as there is the possibility of having collaborators of different nationalities in the same article.

Conclusion

The profile of ASCRO's scientific production shows a predominance of original studies carried out in the areas of Dental Material, Behavioral, Epidemiologic & Health Services Research, with growing participation of foreign researchers.