This article is the author´s pre-print version of the article published in SCIENTOMETRICS 2010;83(3):723-37

Challenges in the study of Cuban scientific output
RICARDO ARENCIBIA-JORGEa,b and FELIX DE MOYA-ANEGÓNb
 
a Network of Scientometric Studies for Higher Education, National Scientific Research Center, 
Avenida 25 y Calle 158 street, AP 6414 Havana (Cuba) 
ricardo.arencibia@cnic.edu.cu
b CSIC, Institute of Public Goods and Policies, SCImago Research Group, Albazans 26-28, Madrid, (Spain)
felix.demoya@cchs.csic.es

Abstract
Cuban scientific output at macro level has not been frequently studied in the literature on scientometrics. The current paper explores the different metric approaches to the Cuban scientific activity carried out by national and international authors. Also, the article develops a scientometric study of the Cuban scientific production as included in Scopus during the period 1996-2007, using socio-economic indicators combined with bibliometric indicators supported by the SCImago Journal & Country Rank. Web of Science and Scopus are compared as information sources. Results confirm the possibility to use Scopus to obtain an objective picture of the Cuban science behaviour during the end of the 1990s and the beginning of the XXI century. The SCImago Journal & Country Rank, in this case, offers an important set of indicators. The combination of these indicators with those related to socio-economic aspects of activities in Science and Technology, allow the authors to show a perspective of the Cuban science system evolution during the period analyzed. The inclusion in Scopus of less-cited journals published in Spanish language and its impact on productivity and citation-based indicators is also discussed. Our investigation found an increasing growth of the Cuban scientific production during the whole period, which is in correspondence to the country efforts and expenditures in Research and Development activities.

Keywords: Scientific output, bibliometric indicators, socio-economic indicators, databases, GDP, Cuba.

Address for correspondence:
RICARDO ARENCIBIA-JORGE
National Scientific Research Center
Department of Scientific Information 
Avenida 25 y Calle 158 street, AP 6414.
Havana City, Cuba.
E-mail: ricardo.arencibia@cnic.edu.cu

*This paper is an extended version of the Research in Progress “Cuban Scientific Production in SCOPUS 1996-2007: a Scientometric approach using the SCImago Journal & Country Rank”, presented in the 12th International Conference on Scientometrics and Informetrics ISSI 2009.
 
1. Introduction
Cuban scientific output at macro level has not been frequently studied in the national and international literature on scientometrics. The first serious approach was developed by Frederick Wilfrid Lancaster and colleagues, from the School of Library and Information Science in the University of Illinois, who used a sample of Cuban articles to examine the extent to which use of published information sources was associated with changes in the political ideology of the country in which a scientist resides (Lancaster et al. 1986).
The study was carried out in the last period of the “cold war”, in a historical context characterized by political conflicts and growing tensions between the island government and the administration of the United States. Their objective was to find the influences of political factors in patterns of use of information sources by Cuban scientists, during the period 1950-1983. Taking into account the close relations between Cuba and the countries from the socialist bloc of Eastern Europe after the Cuban revolution, an increasing citation activity to sources from these countries and a decrease of citation to sources from Western countries would be expected.
However, the results offered a different view. The increase in citation to the Eastern bloc was not accompanied by a corresponding decrease in citation to the West (Lancaster et al. 1986), which was in correspondence to the results observed years before by Nalimov and Mulchenko (1969) in scientists from the Soviet Union. In fact, Cuban scientists cited Eastern sources more than expected only in those cases in which they collaborate with Eastern authors or publish in Eastern journals (Lancaster et al. 1986).
A second approach to the Cuban scientific output was carried out by L. P. Moral, a researcher from the History and Organization of Science Study Center (CEHOC) of the Cuban Academy of Science. His work was developed from a technometric perspective, with the aim to demonstrate the potential usefulness of patents as information sources, and to describe some tendencies of national innovation and R&D efforts (Moral 1989). Moral developed the first patent analysis to study the behaviour of applied research and different aspects related to the generation of technologies in Cuba, during the period 1968-1983. Some of the most surprising results of this paper, taking into account the period studied, were the identification of Switzerland, France, England and the German Federal Republic as the four countries with the biggest amount of applied patents in Cuba, and the absence of nations from Eastern Europe among the eight most active countries (Moral 1989).
After an analysis of the different technological fields with higher patent activity, Moral finished his article with three important questions to be answered by further research: What is the productivity of national inventive activity? What is the productivity of the different research institutions? What is the efficiency of the “patent generating system”? (Moral, 1989) However, these topics have not yet been investigated in depth. 
A third important paper introducing Cuban scientific activity in the international specialized literature was carried out in 1990, as a result of collaboration between the academies of science from Cuba and the German Democratic Republic. W. Meske, from the German Institute for Theory, History and Organization of Science and M. C. Fernández de Alaiza, from CEHOC, presented and discussed the experiences and results obtained in the course of building up national statistics on science and technology (Meske and Fernández de Alaiza 1990). The relation of input/output indicators of the country was presented by first time, using input data from the National Statistics Office (ONE) and bibliometric data for the period 1973-1984, using the Science Literature Indicators Database of the National Science Foundation (NSF), available at the Science Policy Research Unit (SPRU) of the University of Sussex, United Kingdom. Meske and Fernández de Alaiza early identified the relatively small Cuban scientific production in correspondence to the amount of resources and R&D efforts developed by the country; and they used citation statistics to show the still lower visibility of Cuban papers, presenting a rate of 0.81 citations per publication during the period studied. After a deep analysis of socio-economic indicators, the authors diagnosed an increase of the scientific potential of the country during the next decade, but remarked that the rate of development and the social effectiveness of its use was decisively dependent upon the solution of human resources qualification problems, the economic possibilities for the provision of sufficient financial and material funds, and the continued implementation of a demand-oriented structure of deployment (Meske and Fernández de Alaiza 1990).

2. Quantitative approaches to the Cuban scientific output
Probably the most relevant bibliometric study of Cuban scientific activity, from a quantitative perspective, was developed by Rosa Sancho, from the Spanish National Research Council (CSIC), and two colleagues from the Cuban Institute of Research in Sugarcane Byproducts (ICIDCA), in 1993. The authors analyzed the Cuban scientific production during the period 1985-1989 using nine international bibliographic databases (Sancho et al. 1993).  They found that agriculture, biomedicine, chemistry and engineering were the scientific fields that concentrated the greater research efforts. 
The Cuban contribution to the mainstream science, and the scientific collaboration were two topics studied in depth by the paper of Sancho et al., which observed a gradual increase of Cuban articles in the Science Citation Index (SCI) during the period 1985-1989, and showed not only the close relations between Cuba and the countries from the European socialist block during the studied period, but also the role of universities in the knowledge production of the country. 
During the 1960s, higher education became a key player in the social development of the country. Universities in particular became relevant players in building the emerging national science sector (Pérez-Ones and Núñez Jover 2009). This was possible thanks to the University Reform, carried out in 1962, which transformed Cuban universities into institutions capable of producing, absorbing, disseminating and applying knowledge of economic and social importance (Higher University Council 1962). In this sense, the work of Sancho et al. revealed how these changes had an impact on the growth of the national scientific output during the 1980s, and especially at the end of the decade (Sancho et al. 1993).
However, the disintegration of the socialist regime in the countries from Eastern Europe changed dramatically the geopolitical picture of the world, and the emergent Cuban science went through a new process of transformation. The economical crisis forced the Cuban scientific community to play a more direct and intensive role in the economic and social development, generating new sources of wealth for the country and improving the applicability of the scientific results (Pérez-Ones and Núñez Jover, 2009). Scientific and technological policies were oriented toward the use of scientific results in daily practice (Rodríguez 1997), and new actors played an important role in increasing national outputs. Some of these actors were the biotech-based medical-pharmaceutical industry, and the institutions belonging to the scientific and technological park from the west of Havana (Lage 2006). 
The scientometric analysis of this new stage, from a quantitative approach, was developed by Araujo et al. (2005), who observed the growth of the Cuban scientific production in mainstream journals from 236 articles in 1988 to 734 articles in 2003. Their work called attention to the different problems in the use of ISI citation databases to measure national scientific activity. Moreover, a comparison among this database and CubaCiencias, a national database with the aim to cover the total amount of Cuban scientific papers in all fields of knowledge, revealed serious shortcomings also in CubaCiencias. In fact, the creation of a national information system for the construction of scientometric indicators for evaluative purposes is still an idea in progress.
At micro or meso levels, Cuban scientific production has been analyzed from different perspectives. Some papers compare the national behavior with the rest of the Latin American countries, specially in subjects in which Cuba have reported remarked advances, as the research on AIDS (Macías Chapula 2001), vaccines production (Guzmán Sánchez et al. 1998), clinical trials (Araujo Ruíz et al. 2002) or agricultural sciences (Guzmán Sánchez et al. 2002; Licea de Arenas et al. 1994; Torricella Morales et al. 2000; Moya Anegón et al. 2006). 
None of these studies make a deep analysis of socio-economic indicators and its relation with bibliometric indicators, except a paper published by Félix de Moya Anegón and Víctor Herrero Solana, from the University of Granada, Spain, which revealed the situation of Cuba in the Latin American context (Moya Anegón and Herrero Solana 1999). The authors identified some critical points reflecting the complex situation experienced by the country during the 1990s: low rates of scientific collaboration with the United States, as a clear indicator of Cuba’s isolation policy implemented by the American government; difficulties to publish in United States journals, which revealed another problem of a political nature; an important scientific potential in terms of human resources, but a low correspondence of this aspect with the enhancement of the scientific production, a situation also observed in Eastern European countries. 

3. Aim of this study
The paper by Moya Anegón and Herrero Solana (1999) presented Cuba as an atypical case in the Latin American context. Their results also gave evidence to the necessity for a deeper study of the Cuban Science through a more elaborate and holistic analysis of the national scientific production, using a battery of socio-economic and bibliometric indicators that reflect a more accurate scientometric picture of the country during the end of the 1990s and the beginning of the XXI century.
ISI databases have been used in almost all papers related to the Cuban scientific output. Recent studies however begin to use SCOPUS as data source, and different authors have analyzed the possibility to use this Elsevier database as an alternative information source for scientometric studies and evaluations of research performances (Falagas et al. 2008b; Moya Anegón et al. 2007). The appearance of the SCImago Journal & Country Rank, developed by the Spanish SCImago Group, allows the scientific community to take into account this possibility more seriously, and gives specialists the opportunity to develop comparative studies between both databases (Falagas et al. 2008a).
Therefore, the current research is a scientometric study of the Cuban scientific production during the period 1996-2007. The aims are the analysis of the input-output relation during the whole period, the comparison of Web of Science and Scopus for a scientometric analysis of the Cuban scientific growth, and the presentation of  bibliometric measures of Cuba supported by the SCImago Journal & Country Rank (SJ&CR).

4. Method
Different information sources were used in the current paper. Socio-economic indicators of the country related to the period 1996-2007 were obtained from the Cuban National Statistics Office. Bibliometric data for the same period were obtained from the two most important databases and citation tools of the scientific and scholarly world: Web of  Science (WoS), the online version of the classic citation indexes developed by ISI (now Thomson Reuters); and Scopus, the European alternative proposed by Elsevier. Bibliometric indicators for a deeper study of productivity, impact and collaboration in the Cuban scientific production were obtained from the SJ&CR (http://www.scimagojr.com), a scientometric tool developed by the SCImago research group that presents scientometric analysis through a set of indicators based on Scopus data.

The following set of indicators was employed:
Socio-economic indicators:
Expenditure on R&D; expenditure on R&D as a percentage of GDP; total number of researchers.
Indicators for the quantitative dimension of the scientific production:
Total number of articles; productivity (articles per researcher); Relative Specialization Index (of Cuba with respect to Latin America, based on the Activity index).
Indicators for the qualitative dimension of the scientific production:
Percentage of cited articles; average of citations by article; H index.
Indicators for the scientific collaboration:
Percentage of international collaborations.
Indicators for the structural dimension:
Multivariate representations.

All searches in databases were carried out in June 2009. The indicators obtained from the SJ&CR were collected using the version available on that date.

5. Results
5.1. Socio-economical approach
A common practice in scientometrics is to study the importance of the structure and efficacy of R&D activity, specially its relation to the GDP, on the development of a national science policy (Vinkler 2008). In fact, literature assumes that GDP of countries is a linear or exponential function of their scientific output (King 2004). However, national budgets for Science and Technology activities or national science policies, and the evaluation of its impact and effectiveness, are topics widely discussed during the last years, not only in developed countries, but also in developing nations. 
It is known that the scarcity of resources is a central factor in a national science policy, but frequently a developing nation faces up a more complex context. On the one hand, sometimes social or economical factors have a big incidence in the availability or not of a high budget to spend in scientific and technological development. On the other hand, sometimes there is not an adequate evaluation system to control the effectiveness of the invested resources. Therefore, economical problems, unfocused priorities and misuse of resources usually have the same consequence: a bad position in rankings based on scientific production.
Cuba is an interesting case in this sense. The country has a well defined system of social priorities, supporting the national science policy. That is the reason of the incidence of this policy in a series of social development indicators. For example, a high number of doctors per capita, one of the world lowest mortality rates, the lowest infant mortality rate in Latin America (one of the best of the world), a life expectancy ten years higher than the Latin America average, etc. However, national science policy (closely related to educational and health policies of the country) may have less impact on national scientific production in mainstream journals, affecting its international visibility, one of the aspect to demonstrate in this paper.
Cuban expenditures in Education, Health and S&T comprise approximately 20 % of the national GDP. This indicator has experienced a remarkable growth in Education (from a 6,8 % of GDP in 1995 to 9,3 % in 2006) and Health (from a 5,1 % of GDP in 1995 to 9,9 % in 2007)  (ECLAC 2008). Despite a linear growth in Cuban S&T and R&D expenditures during the period analyzed, its evolution expressed as a percentage of GDP apparently does not show a very significant development (Figure 1).

Figure 1. Evolution of the Cuban expenditure in Science and Technology activities (S&T) and Research and Development (R&D) during the period 1996-2007.

Specially, R&D expenditures only grew from 0.35 % of GDP in 1996 to 0.58 % in 2007. However, this increase (0.66%) is still higher than that observed in the other most productive countries from the region, including Spain (0.57) and Brazil (0.42), the only countries with R&D expenditures higher than 1 % of the GDP (see the website of the Ibero-American network on science and technology indicators, http://www.ricyt.edu.ar/). Clearly, a positive conclusion can be made according to this point: the Cuban government increased its expenditure in S&T and R&D during the whole period studied.

5.2. R&D expenditure and research productivity
The effect of this increment on the national scientific production in highly visible journals can be observed according to the two data sources used in the current paper: the WoS and Scopus (Figure 2). There is a moderate to significant correlation between R&D expenditures and scientific production in WoS (r=0,89) and Scopus (r=0,73). However, the linear growth is clear in the socio-economic indicator and the scientific production covered by the WoS, and it is somewhat irregular in the output covered by Scopus. 
Preliminary studies of the authors of the current paper identify some factors that explain better this situation. First, Scopus has a retrospective covering policy; that is, all the articles published by a journal covered by Scopus are processed by the database, no matter the year in which had been published. This is completely different to the coverage policy of ISI databases, which include the articles since the year in which the journal is covered by the database, not before. This leads to clear differences between both databases. Therefore, Scopus data are highly dependent on the coverage policy, and Scopus output measures of a country in a specific year can be radically different from those in consequent years. 

Figure 2. Evolution of the Cuban expenditure on R&D and the scientific production in SCOPUS and the Web of Science during the period 1996-2007.

On the other hand, a big amount of Cuban scientific journals were covered by Scopus since 2006. So, the retrospective covering process is still on its way. That would be the reason of the lack covering of articles published in Cuban journals during the years 2003 and 2004. The inclusion of those articles during the next years can change the less significant value of the determination coefficient observed in the linear growth, and then, a similar behaviour of the tendencies would be observed in both databases.
The productivity by researcher shows the same behaviour of the scientific output in both information sources. That is because the number of researchers reported during the whole period shows only little variation. The covering problems of Scopus during 2003 and 2004 affect again the linear growth of the indicator (Figure 3).

Figure 3. Evolution of the total number of Cuban researchers and the productivity by researcher in the Web of Science and SCOPUS during the period 1996-2007.

Despite these irregularities presented in data reported by Scopus, it is evident that this database shows a better picture of the Cuban scientific activity, and must be taken into account in future assessments of the national research efforts.  The effectiveness of the databases to measure Cuban output will be the next topic to discuss.

5.3. Measuring Cuban scientific output: Web of science versus Scopus.
There are numerous factors that contribute to choose Scopus as information source in the current paper. ISI databases have been the traditional tools for scientometric studies, but the emergence of Scopus is due to its coverage, flexible data and advances features (Tomizawa 2008). The advantage of Scopus with respect to ISI databases in citation analysis originating from the breadth of its database is limited to the time period after 1996 for which citation analysis is available (Falagas et al. 2008b). However, Scopus includes a substantially larger collection of journals, originating from considerably more countries and published in a greater variety of languages (Falagas et al. 2008a). 
Non-English languages journals, for example, are rather underrepresented in ISI databases. In this respect Latin American countries are better represented in Scopus. Although the proportions of Spanish- and Portuguese-language journals are the same in the WoS and Scopus (Leydesdorff, Moya-Anegón and Guerrero-Bote 2009), the total amount of covered journals is two and three times higher in Scopus. This aspect is very important in order to analyze Spanish or Latin American science from a non-ISI perspective. However, taking into account the coverage policy of the database, which prevent to obtain similar measures in different dates when a retrospective search is developed, there is no doubt that the use of Scopus as alternative source for scientometric studies and research performances evaluation must be studied in more detail. Scopus still is too young. So, despite interesting results published on their advantages, the real potential of the database will be observed in the near future.
The Organisation for Economic Co-Operation and Development (OECD), for example, has recently decided to develop an Innovation Strategy to help governments boost innovation performance, and announced in October 2008 its decision to use Scopus custom data in its research, analysis and benchmarking work (Tomizawa 2008). In Cuba, the Network of Scientometric Studies for Higher Education project has developed research that show the state-of-the-art of different knowledge domains using Scopus data (Arencibia Jorge et al. 2008; Collymore Rodríguez et al. 2008; Hung Llamos et al. 2008). Particularly, Cuban neuroscientists’ research performances have been tackled from different perspectives and using H-index based indicators (Arencibia Jorge and Rousseau 2009; Dorta Contreras et al. 2008). 
The current paper clearly shows some advantages of using Scopus as analytical tool for the Cuban scientific output (Table 1). 
Table 1. Comparative analysis of Cuban impact indicators in the Web of Science and SCOPUS during the period 1996-2007.
Indicators	Cuba in WoS	Cuba in SCOPUS	
Articles	8,642	13,548	
Journals	1	20	
Citations	50,026	53,643	
Cited articles	5,713	6,977	
Percentage of cited articles	66.1	51.5	
Average number of citations by article	5.79	3.96	
H index	61	62	
* Data retrieved in May, 2009.

ISI databases only cover one national journal: the Cuban Journal of Agricultural Science, which is the cause that agriculture was a well represented domain in the total production of the country, and one of the most analyzed domains by national and international authors (Guzmán Sánchez et al. 2002; Licea de Arenas et al. 1994; Torricella Morales et al. 2000; Moya Anegón et al. 2006)
The traditional agricultural orientation of the Cuban scientific production changes in the Scopus environment. The reason is simple: a total of 20 Cuban journals, most of them specializing in biomedical sciences, are covered by Scopus. Of course, a total of 4 906 articles more (more than a half of the total national production in ISI databases) offers a new thematic dimension (Figure 4).

Figure 4. Relative Specialization Index (Activity) and H index of the Cuban scientific production by SCOPUS subject areas during the period 1996-2007.
Subject Areas abbreviations: Agricultural and Biological Sciences A&BS; Arts and Humanities A&H; Biochemistry, Genetics and Molecular Biology BG&MB; Business, Management and Accounting BM&A; Chemical Engineering CE; Chemistry CH; Computer Science	CS; Decision Sciences DS; Dentistry DE; Earth and Planetary Sciences E&PS; Economics, Econometrics and Finance EE&F; Energy EN; Engineering ENG; Environmental Science ES; Health Professions HP; Immunology and Microbiology I&M; Materials Science MS; Mathematics MA; Medicine MD; Multidisciplinary MU; Neuroscience NE; Nursing NU; Pharmacology, Toxicology and Pharmaceutics PT&P; Physics and Astronomy P&A; Psychology PS; Social Sciences SS; Veterinary VE.

Figure 4 combines scientific production (size of the bubbles), relative specialization (in the Latin American context), and impact (H index). In a regional context, Cuba has a clearly biomedical orientation. The Scopus subject areas in which Cuba is more specialized are: Health professions, Psychology, Medicine and Biochemistry, Genetics & Molecular Biology. The last two mentioned fields show the best performances according to the H index. 
Nonetheless, citation analysis reveals an interesting point: the inclusion of less-cited journals published in Spanish language has a positive impact on productivity indicators, but a negative one on citation-based indicators, which have been observed by Michel Zitt and colleagues in previous studies (Zitt, Ramanana-Rahary and Bassecoulard 2003; Zitt and Bassecoulard 2008). That is, the increment of national journals in the database implies the decrease of impact indicators. The total citations in Scopus, as well as the increase of cited articles, are not in correspondence to the increase of documents. The percentage of cited articles decreases more than a 10 %. The average number of citation by article also significantly decreases. Only the H index shows a positive variation. But the H index only takes into account the core of most cited articles, and it is evident that there are no major differences between the highly visible cores identified in both databases. Although it is too early to draw any definitive conclusion about this negative impact, variables related to this behaviour must be widely studied at macro level in further research, taking into account several limitations of the database reported by the literature (Jacsó 2008; 2009), in order to understand the dynamics of the Scopus coverage growth.

5.4. Cuban scientific output through the SCImago Journal & Country Rank
Scopus based indicators are freely available through the SJ&CR. This scientometric portal was recently developed by SCImago, a Spanish research group from the Universities of Granada, Extremadura, Carlos III (Madrid), Alcalá de Henares, and the Institute of Public Goods and Policies from CSIC, dedicated to information analysis, representation and retrieval by means of visualization techniques. The SJ&CR includes journals and countries scientific indicators developed from the information contained in the Scopus database, which could be used to assess and analyze scientific domains. This portal offers a serious alternative to the classic Thomson Reuters services Essential Science IndicatorsSM (ESI) and Journal Citation Report (JCR) (Falagas et al. 2008a).
Preliminary reports from the SCImago research group show that Cuba is the Latin American country with the highest growth in output if we compare WoS and Scopus, with a variation ratio of 65,7 % in the year 2007. According to the ESISM, and taking into account the scientific production of the country during the latest 10 years, Cuba is situated on the 63rd place of the country ranking (the seventh most productive country of Latin America). However, Cuba goes up five places in the SJ&CR, which cover the period 1996-2007, where it is situated on the 58th place.
The version available in June 23 (2009) of the SCImago Journal & Country Rank presents a total of 16 Latin American countries with more than 1,000 articles during the analyzed period. Cuba is the seventh most productive country (Table 1).

Table 2. The most productive countries from Latin America in SCOPUS during the period 1996-2007 (+ 1000 articles).
Country (Abbr.)	Articles	Citable Articles	Cites	Self-Cites	Cites per Doc.*	% Cited Doc	% Col Int	H index	
Brazil (BRA)	197.705	192.615	1.036.204	331.101	5,24	61,14	33,54	179	
Mexico (MEX)	82.792	80.945	470.643	112.239	5,68	62,62	42,22	134	
Argentina (ARG)	64.630	63.051	422.383	101.758	6,54	68,12	39,12	131	
Chile (CHL)	31.137	30.441	234.489	47.196	7,53	68,01	55,37	119	
Venezuela (VEN)	15.416	15.068	80.335	14.506	5,21	59,25	45,44	85	
Colombia (COL)	11.238	10.924	61.088	9.442	5,44	59,22	59,89	73	
Cuba (CUB)	10.342	10.005	43.335	11.230	4,19	53,05	54,09	57	
Puerto Rico (PUR)	5.867	5.724	55.577	4.898	9,47	68,55	61,96	78	
Uruguay (URU)	4.763	4.607	38.870	6.097	8,16	71,82	62,76	68	
Peru (PER)	3.710	3.568	26.712	3.176	7,20	67,79	79,00	57	
Costa Rica (CRI)	3.423	3.336	28.679	4.015	8,38	71,66	70,23	61	
Ecuador (ECU)	2.028	1.947	13.495	1.757	6,65	63,07	71,84	47	
Jamaica (JAM)	2.004	1.879	11.626	1.613	5,80	64,27	44,06	39	
Trinidad and Tobago (T&T)	1.853	1.748	7.842	957	4,23	58,82	49,27	34	
Panama (PAN)	1.675	1.596	23.609	2.814	14,09	79,04	85,25	64	
Bolivia (BOL)	1.338	1.310	9.187	1.068	6,87	70,25	86,47	35	
									
Latin America	429248	418100	2460412	697541	5,73	62,90	39,26	243	
* In the SCImago Journal & Country Rank, Cites per Doc. Indicator for the whole period is calculated as the mean of the annual average of citation by article, with the aim to minimize the influence of extreme values during a year. In this table, it is calculated this indicator dividing the total of cites received during the whole period by the total of articles published in it.

However, compared with the rest of the most productive countries from Latin America, the visibility of the Cuban scientific production is still low. The percentage of cited articles and the average number of citations by article are below the mean values of Latin America; and the percentage of international collaboration still does not exert influence on the impact indicators. 
Cuban average number of citations by article is the worst of the 16 most productive Latin American countries in Scopus (Figure 5). Despite the improvement of the production indicators, this relative impact places Cuba among the countries with lower international visibility, on the 165th place of the world ranking. 

Figure 5. Relation between the percentage of cited articles, the average of citation by article and the H index of the most productive Latin American countries in SCOPUS.

This aspect reveals again the problem discussed before related to the inclusion in Scopus of less-cited journals published in Spanish language and its negative impact on citation-based indicators. However, the position of Cuba in the country ranking of the ESI (110th place) is lower too. Therefore, this low international visibility of the Cuban scientific production is a multi-causal phenomenon, and must be studied from different perspectives in further research.
A clear example is the analysis of the international collaboration, an aspect widely discussed in scientometric studies (Narin et al. 1991; Glänzel 2001; Glänzel and Schubert, 2004; Moed 2005). Internationally co-authored papers tend to have higher citation rates than those published exclusively by national authors. In the case of Cuba, the percentage of internationally co-authored papers is relatively higher than that reported for the most productive Latin American countries (Figure 6). In this most productive core, only Colombia and Chile have a higher percentage. On the other hand, the less productive countries are most dependents on the international collaboration, and that influences positively in their averages of citations by article. However, despite Cuban scientific production shows wide participation of international institutions, the relative impact is low. This behaviour is more or less similar to that of Colombia.

Figure 6. Relation between the percentage of cited articles, the average of citation by article and the H index of the most productive Latin American countries in SCOPUS.

The impact of the journals that publish the results, the prestige of international partner institutions, the research fields, and many other factors, must be further analyzed in order to find an objective explanation to this paradoxical behavior at the macro level.
Undoubtedly, the SJ&CR is a freely available tool that facilitates the analysis of the world scientific production, and specially reveals the state-of-the-art of disciplines and subject areas, and the behaviour of the different countries. Scopus’ advantages and limitations are inherent to the indicators proposed in the portal, but this is no different for the classic Thomson Reuters’ services based on ISI databases. 
Finally, the indicators exposed by the SJ&CR offer an interesting view of a considerable higher volume of the Cuban scientific output, with respect to WoS. The impact indicators reveal a problematic dependent of the coverage policy of Scopus. But anyway, the massive incorporation of Cuban articles in Scopus is still very recent. More time is needed in order to achieve better and objective approximations to the visibility of the Cuban scientific production through a Scopus-based citation analysis. 

6. Conclusions
The results presented in this paper confirm the possibility to use Scopus in order to obtain a more objective picture of Cuban scientific output. The SJ&CR, in this case, offers an important set of indicators. The combination of these indicators with those related to socio-economic aspects of Science and Technology activities, allow the authors to show a perspective of the Cuban science system evolution during the end of the 1990s and the beginning of the XXI century. It was observed an increasing growth of the Cuban scientific production during the analyzed period, which is in correspondence to the country efforts and expenditures in Research and Development activities. It is observed that more time is needed to measure positive or negative implications of the inclusion of less-cited journals published in Spanish language for Cuban citation-based indicators.

Acknowledgments
To Zaida Chinchilla Rodríguez, Elena Corera Alvarez, Víctor Herrero Solana, Rosa Lidia Vega Almeida, María del Carmen Osuna López, María Benavent Pérez, Yaniris Rodríguez Sánchez and Ronald Rousseau, for their support and advices. This research was possible thanks to a research grant in the Institute of Goods and Public Policies of CSIC, and it is a result of the Doctoral Program on Documentation and Scientific Information developed by the University of Granada, Spain, and the University of Havana, Cuba. Access to Elsevier and Thomson Reuters databases was possible thanks to the Spanish Foundation for Science and Technology and the Ministry of Science and Innovation of the Spanish government. 

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