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Library Philosophy and Practice Vol. 2, No. 2 (Spring 2000)

ISSN 1522-0222

Environmental Impact: A Preliminary Citation Analysis of Local Faculty in a New Academic Program in Environmental and Human Health Applied to Collection Development in an Academic Library

Bill Johnson

Science Librarian
Arizona State University East
7001 E. Williams Field Rd.
Building 20 Mail Code 0180 
Mesa AZ 85212
FAX 480-727-1077

This paper was also published in the March 1999 issue of the electronic journalLIBRES: (www.curtin.edu.au/curtin/dept/sils/libres/libre9n1/toxcite.htm)


New academic programs in environmental science prompted a citation analysis of local faculty by the Texas Tech University Library (TTU). The purpose of this study is to characterize the citation patterns of the interdisciplinary field of environmental and human health as compared with other disciplines and to apply the results to collection development. Twenty-four articles were selected from 1996 and 1997 with over 1,600 citations to more than 950 listed references. The average age of citations was 10.5 years for journals and 9.4 years for books. On average, journals were cited 67 percent of the time while books were cited 17 percent of the time. Proceedings, theses, and technical reports were also cited but that data was not applied to collection development. The impact on collection development has been to identify a small number of specific books which were frequently cited but were not in the collection and to identify important subject terms with which to guide the selection of related books. Finally, twelve new subscriptions to frequently cited journals will be reviewed with faculty to determine their suitability as additions to the collection.


In response to two distinct requests from life science faculty on the TTU campus for a description of library support for new environmental studies programs, a document was prepared describing the collection, document delivery service options, spending patterns for acquisitions, etc. (Appendix E) In order to better understand how to support the research activity of these faculty, especially the group at the new Institute of Environmental and Human Health (TIEHH), a citation analysis was undertaken which would allow for refining the original description of program support by the University Library. It was also hoped that such a study would add a qualitative dimension to the Library's effort to gather use data amidst an ongoing debate over the validity of journal reshelving counts.

TIEHH was formed as a joint venture between Texas Tech University and Texas Tech University Health Sciences Center in 1997. It is dedicated to be a leader in research and teaching between environmental and human health. It will implement "good science" and technology in the interface of good environmental policy and economic development. The charter faculty of the Institute (Appendix A) established a solid record of original research and service while at Clemson. A representative sample of their scholarly output in 1996/1997 constitute the study sample for this analysis.

Literature Review

Citation studies reveal much about scholarly communication and can be an effective tool to guide collection development in academic libraries. These studies typically take one of two directions: "local" or "global." Studies of "local" faculty are believed by many to yield more relevant results than "global" investigations to assist librarians making serials selection decisions for their institutions. Aside from practical applications, citation studies offer objective insight into the fundamental research behavior of faculty and graduate students. For example, citation studies have been used to better understand how invisible colleges communicate, to identify discipline specific core journals, to make distinctions in research patterns between pure and applied scientists, etc.

In a study comparing two plant science journals considered either applied or basic in scientific content,(Nordstrom (1987) characterized each based on citation age, proportion of cited formats, number of citations per article, and the distribution of citations among sections of each publication. He reported that basic science publications generally cited more works and that these works tended to be somewhat older than the applied science counterpart. Comparing the results of his study to this one with regard to these two parameters suggests that the group of environmental science faculty in the present study could be considered as belonging to the basic science group. However, Nordstrom suggested that applied scientists relied on journals 68 percent of the time and used technical reports with some frequency. These aspects of the present study suggest that environmental researchers fall into the applied science group. The interdisciplinary nature of environmental studies suggests that they do not fit neatly into either group but lie on a continuum somewhere in between.

Systematics research, like environmental studies is quite synthetic, drawing information from a wide range of other disciplines. This is where similarities end, however. Citations to the taxonomic literature are generally much older and follow a unique set of international "rules and standards." For example, citations associated with synonymies may not appear in the literature cited section of a publication. Some 11 percent of journal citations and 23 percent of book citations could be overlooked if the analysis failed to include the list of synonymies. (Delendick 1989) Many other types of citations may not be listed in the bibliography of an article on taxonomy. The environmental literature studied here also contained citations to scientific and corporate names not listed in the references at the end of some articles. While the frequency of this practice was not measured, 36 percent of the articles studied had such "non-bibliographic" citations.

Faculty citation patterns reflect dynamic research priorities, offering guidance as academic libraries seek to support campus research and teaching activities. Library support for scientific research has become quite a challenge at the end of the 20th century due to shrinking budgets, escalating costs of scientific journals, and the advent of the electronic journal. Local citation patterns can help serials managers make objective selection decisions, saving money and creating a collection that will be more widely used. (McCain 1981)

Citation studies of the scientific literature consistently demonstrate that journals continue to be more heavily utilized in the exchange of information with some disciplines reporting that journals are cited as much as 92 percent of the time with all other formats making up the remaining 8 percent of citations. (Walcott 1994) It is often helpful to conduct some form of faculty survey in association with a citation study to uncover complimentary information and clear up questions prompted by the citation analysis. (Crotteau 1997) While no formal survey was conducted here, numerous email messages have been exchanged with faculty and have proven helpful in keeping this study on track. For example, some faculty were not aware that some journals were available electronically through Academic Press (IDEAL). The dialogue prompted by this study has fostered an exchange of information about products and services offered by the University Library making faculty more aware of how the Library supports their teaching and research activities in a growing electronic landscape.

Comparisons between local citation patterns and the international data provided byJournal Citation Reports (JCR) of the Institute of Scientific Information help to point out the strength of journals among the international research community. A frequently used international ranking, referred to as an impact factor, has been used by some in identifying "core journals" or journals considered basic to any collection offering coverage in a corresponding discipline. (McCain 1991) Impact factors from the JCR are found in the list of journals cited for a global perspective on the importance of the journals cited by faculty in this study. (Appendix B) Yet, a high impact factor alone does not necessarily mean that a particular journal should be added to a collection since other factors such as local research interest and price should be considered.


A narrowly defined group of faculty and their scholarly output are essential first steps in this qualitative study. In order to better understand and support the new program in environmental and human health on campus, the charter faculty at the Institute of Environmental and Human Health were selected. Graduate student theses from this institute could offer the opportunity to refine these faculty findings in the future. The most recent, complete two years (1996 and 1997) of published research were selected to keep the sample size from becoming unmanageable and to insure timely relevance to present research needs. The fact that only the scholarly output of local faculty were considered is a good measure of local relevance. The University Library's mission is to support specific campus programs, therefore, a generic study on environmental research around the world, may be of interest for comparative purposes, but it would not be as useful to apply to collection building in the University Library.

Locally available FirstSearch databases were searched by author, including Agricola, BasicBiosis, Environment, CAS Student Edition, Medline, and Biological and Agricultural Index. It was difficult to specify authors in those databases where they did not include the author's first name. A listing of faculty publications was also consulted on the TIEHH website. Due to time limitations, a representative sample rather than a comprehensive collection of publications was sought. Interlibrary loan services were heavily utilized. Each article was reviewed in its entirety rather than simply examining the list of sources at the end of the article since some of these sources were not cited at all while others were cited to varying degrees throughout the paper.

A spreadsheet program was used to list, organize, and perform calculations on cited sources. Two distinct files were created, one to characterize the author's articles and the other to examine the cited sources in those articles. References were classified as either journals, books, theses, technical reports, or proceedings. Journal abbreviations were translated into full titles using standard reference tools. Non-literary citations were noted along with non-bibliographic citations, which refer to literature that may be so fundamental as to be taken for granted and not listed in the article's bibliography. (Delendick 1989)

Two definitions should be kept in mind. The first is, "Technical Report." It is easier to say what this is not, rather than what it is. Technical reports in this study are not journals, books, proceedings, or theses. In other words, they are most any thing else, including patents, departmental publications, agency reports, etc. The second is, "Self Citation." Authors frequently cite themselves for a variety of reasons. All TIEHH charter faculty were considered authors of every article in this study whether or not they appear as such. Due to the team-like structure of this group, it is likely that they are more apt to be aware of each others' publications, regardless of how the authors of each paper are listed.



The twenty-four publications studied herein listed over 950 references which were cited more than 1,650 times. A few papers listed references that were never cited. This occurred, five percent of the time on average. Most of the bibliographies with these articles included self citations, that is references to works authored by colleagues. This occurred an average of 13% of the time. In general these publications were twelve and one half pages long and authored by five individuals. They listed thirty-nine references which were cited sixty-five times, on average.

TABLE 1: Format Proportion and Average Age of Cited Works

Format of Cited Works

Relative Proportion When Present (%)

Average Age (yrs)

TTU Owned (%)









Technical Report












The range of formats cited was quite diverse, including journals, books, technical reports, theses/dissertations, electronic databases, and non-literary sources. (Table 1) The latter includes references to the scientific names of organisms, soil classifications, corporate names, and of course - personal communication. Many of these references could be traced to a literary source, such as the original publication documenting the first time an organism was identified, named, and described. Thirty-six percent of the publications studied, included such citations, but they were rarely listed in the references. Not every format was represented in each citing publication so the overall percentage may not equal one hundred. But when present, these formats were cited proportionally as listed in Table 1.

The age of cited works was much less diverse. (Table 1) It was surprising to find that the average age of a journal citation was greater than all other formats - ten and a half years. This age corresponds with other disciplines such as systematic botany (Delendick 1989) and statistics (Johnson 1996), yet the literature of environmental and human health is fundamentally different than these other disciplines. For one thing, while the literature of plant taxonomy and the environment are both quite interdisciplinary, the former is more descriptive, the latter presents experimental studies conducted in the field or laboratory. More timely reporting of such experiments was expected. This result alone carries important implications for collection development as discussed in the next section. Statistics faculty, on the other hand, rely more heavily on books with their slower publication schedule than do the environmental scientists, yet this explanation is inadequate in and of itself to account for the similarity between theses disciplines in the average age of cited research.


Holdings of specific titles of the more heavily cited journals (Appendix B) and books (Appendix C) were searched for in the TTU Library online system. It was found that 58 percent of the books and 66 percent of the journals are now in the collection. Eight additional book titles from the list are considered suitable for the collection and were purchased, bringing the current holdings of cited books to 73 percent. Additional books were selected based on subject terms associated with cited books, key words as listed in some of the faculty publications, and the TIEHH website of current research projects. (Appendix D)

All heavily cited journals not currently subscribed to (twelve titles), could be reviewed with faculty to determine whether or not it would be appropriate to initiate a subscription at this time. The tendency of this group to cite older journals, suggests that membership in JSTOR may be appropriate since these retrospective electronic holdings are older than five years. It should also be noted that, for the most part, the heavily cited journals by this group of faculty also have rather high impact factor ratings by ISI, the Institute for Scientific Information. Proceedings, technical reports, and theses were not incorporated into the collection development process as a result of this study due to the relatively low number of citations found for each group and the greater difficulty of acquiring these materials.


Completion of this report was made possible by the generous support of the TTU Libraries, granting developmental leave to analyze the data and write up the results. The cooperation and interest of faculty at the Institute of Environmental and Human Health is gratefully appreciated. Finally, I would like to thank my wife Debbie Johnson for assisting with the data entry.


Crotteau, Mark. Support for Biological Research by an Academic Library: a Journal Citation Study.Science and Technology Libraries 1997, vol. 17(1): 67-86.

Delendick, Thomas J. Citation Analysis of the Literature of Systematic Botany: a Preliminary Survey.Journal of the American Society for Information Science 1989, ol. 41(7): 535-543.

Johnson, Bill. Citation Analysis of the Texas Tech University's Statistics Faculty: a Study Applied to Collection Development at the University Library.LIBRES: Library and Information Science Research 1996, vol. 6(3):www.curtin.edu.au/curtin/dept/sils/libres/libre6n3/johnson.htm.

McCain, Katherine W. and James E. Bobick. Patterns of Journal Use in a Department Library: a Citation Analysis.Journal of the American Society for Information Science 1981 vol. 32(4): 257-267.

McCain, Katherine W. Core Journal Networks and Co-citation Maps: New Bibliometric Tools for Serials Research and Management.Library Quarterly 1991 vol. 61(3): 311-336.

Nordstrom, L.O. Applied Versus Basic Science in the Literature of Plant Biology: a Bibliometric Perspective.Scientometrics 1987 vol. 12(5-6): 381-393.

Walcott, Rosalind. Local Citation Studies - a Shortcut to Local Knowledge.Science and Technology Libraries 1994 vol. 14(3): 1-14.








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