Global Document Delivery and User Studies: The Gateway Experience
	
Rush Miller, University of Pittsburgh
	Hong Xu, University of Pittsburgh
	Xiuying Zou, University of Pittsburgh

1.	Introduction

The Gateway Service Center (GSC) of Chinese and Korean Academic Journal Publications is administered by the East Asian Library, the University of Pittsburgh Library System. Ever since its establishment in 1998 by a grant from the US Federal Institute of Museums and Library Services, the Gateway Service Center has been serving as a model for global document delivery and resource sharing. For the first three years of its operation, the center’s mission was to provide US scholars with Chinese academic journals articles that were not obtainable anywhere in the United States (Miller, 1998; Miller and Zhou, 1999). 
Immediately after the launch of the service, it became well-known and greatly appreciated by Chinese studies scholars in the United States. According to the center’s statistics, from 1999-2002, the center received 2,711 document delivery requests from more than 140 universities and research institutions in the United States, among which 2,255 were successfully filled, achieving a fill rate of 83.2%. The average turnaround time was 7.75 days. Both the fill rate and turnaround time were significantly higher than the ARL statistics in 1999, which was 16 calendar days and 58 % fill rate on average, 13.5 calendar days and 75% fill rate for the ten research libraries with the best performance of interlibrary loan activities ( Jackson, 1997, Xu & Pang, 2003).
The initial success not only promoted the publicity of the University of Pittsburgh and its library collections, but also inspired more libraries in China to join the partnership network and use the Gateway Service to provide scholars in China with materials in Western languages that are not locally available. From 2003 to 2006, Chinese partner libraries increased from six to thirteen, further enhanced the Center’s capability to obtain materials in a wider variety of subject areas. 
New document delivery agreement with partner libraries also changed the direction of document delivery, from unidirectional to reciprocal. Both the GSC and Chinese partners become a gateway, requesting and supplying documents that are not locally available for their patrons. Under this circumstance, it is necessary to review the GSC service and performance over the past three years, study the changing user characteristics and document request patterns, and find out limitations and directions for future improvement.
A study by Hong Xu and Jing Pang in 2003 investigated the characteristics of US-based users of the GSC from 1999-2002. Their research findings indicate that the primary users of the center’s services were faculty, graduate students, and researchers in the United States. The requested materials were mainly in the field of Chinese history, literature, and language. The average fill rate and turnaround time were significantly higher and faster than the ordinary ILL services. Chinese studies scholars in United States sincerely appreciate the unique services provided by the center. Xu and Pang’s study also discussed reasons why requests were delayed or unfilled and offered several suggestions for improving the fill rate. (Xu & Pang, 2003).
As a follow-up, the current study further investigates the characteristics of US-based users and their changing document request patterns at the GSC. Furthermore, it conducts comparative studies on the characteristics of users in both China and the USA, and evaluates the effectiveness of the center’s service in terms of providing English materials to partner libraries in China. Statistic analysis is conducted based on data gathered by the center over the past three years, from January 2003 to December 2005. The following research questions are answered:
a.	Who uses the GSC services and what are their geographic regions and research background? 
b.	What subject areas are the requested materials in? Are there any significant changes over the years?
c.	How does the services provided by the GSC compare with traditional ways of interlibrary loan and document delivery in effectiveness and user satisfaction?
d.	Are there significant differences between China and the United States in terms of user characteristics and their requested materials?

2. The Users and Their Background

2.1 Geographic Distribution

One remarkable feature of the GSC user population over the past three years is the wider geographic distribution, compared to that from 1999-2001, which were mainly US-based. As Table I indicates, from 2003-2005, the GSC received a total of 5922 requests from users in China, United States, and other countries. Among them, 2778 are requests from partner libraries in China, 97 from Hong Kong, 100 from Taiwan, 2692 from the United States, and 182 from 15 other countries.
Table I  Number of received requests and geographic distributions
Region	2003	2004	2005	Grand Total	
				Request	%	
China	766	904	1108	2778	46.9	
Hong Kong	46	42	9	97	1.6	
Taiwan	39	19	42	100	1.7	
United States	1009	701	982	2692	45.5	
Other Countries	133	21	28	182	3.1	
Unknown	70	3		73	1.2	
Total	2063	1690	2169	5922	100	

The wider geographic distribution is due to several factors, the most important of which is the full participation of Chinese partner libraries in the exchange and sharing of resources. As Table I indicates, total requests from Chinese partner libraries amounts to 2975, slightly over 50% of the grand total. Users from countries other than United States and Chinese partner libraries also increased compared to 1999-2001, in which almost all requests were US-based.

2.2	Users’ Occupational Status
Different from traditional interlibrary loan services, the GSC accepts both user-oriented requests and requests via ILL departments. Graduate students, faculty, and researchers inside the United States who are familiar with the center’s service tend to send the requests directly to the GSC. Requests from China are unanimously sent via the ILL departments of the partner libraries. Because of the different operation procedure and requirement for filling out the request forms, requests from the partner libraries usually do not carry information about the requesters’ academic status, field of study, and purpose of requested materials. Same situation applies to US-based requests prior to July 2004, where the online request form then in use did not ask for such information. Therefore, we did not approach this question on a yearly-basis. Rather, we gathered all identifiable data about the user status and report the result in table II.
Table II  Users’ occupational status 2003-2005

User Status	US-Based	Partner Libraries	
	Frequency	% 	Frequency	% 	
Faculty	563	28.5	199	7.1	
Graduate	285	14.4	982	34.8	
ILL	624	31.5	1594	56.5	
Non-university
Researcher	506	25.6	46	1.6	
Grand Total	1978	100.0	2821	100	

Faculty includes both teaching and research faculty, and post-doctoral fellows in colleges and universities. Graduates include master and PH.D degree candidates. ILL refers to interlibrary loan staff at university libraries and other type of libraries and information centers. Non-university researcher refers to those researchers whose primary institutional affiliation is not a higher education institution. From Table II we can see one remarkable difference between the status of Chinese users and US-Based users. The requests from non-university researchers inside United States are much higher than their counterpart in China, accounting for 25.6% of the identifiable US-based requests.
2.3	Users’ Academic Background
For statistic purpose, we group users’ academic background into six broad categories. Under Arts and Humanities (ArtHum) are subject areas such as archaeology, fine arts, performing arts, history, cultural studies, language, linguistics, literature, philosophy, religion, etc. Social Sciences (SocSci) cover anthropology, administration, economics, education, library science, political science, sociology, social work, etc. Business covers accounting, financing, marketing, business administration, etc. Chemistry, psychology and biology are grouped under Science and Technology (SciTech), while biochemistry is grouped under Medicine. This subject classification applies to the subject divisions of the requested materials as well.
According to Xu & Pang’ study in 2003, the GSC users (US-Based) were mainly in the areas of arts and humanities (42.18%), Social sciences (29.68 %), and Science and Technology ( 21.87%). Others (including tourism, food, nutrition) account for 6.25%. Interestingly, users’ academic background for recent years seems to have changed. Table III suggests that US-based users with science and technology background has significantly increased, averaging 63.8% of all identifiable users, while users with medicine background also increased to 8.3%. It is noticeable that the number of users in China with a medicine background is significantly higher than users in the United States, accounting for 60.7% of all identifiable requests.
Table III Users’ study fields 2003-2005

User Status	US-Based	Partner Libraries	
	Frequency	%  	Frequency	%  	
ArtHum	173	19.3	152	11.2	
Business	4	0.4	36	2.6	
Law	6	0.7	23	1.7	
Medicine	75	8.3	825	60.7	
SciTech	572	63.8	215	15.8	
SocSci	67	7.5	109	8.0	
Grand Total	897	100.0	1360	100.0	

2.4  Subject Division of Requested Articles
As is with the change in users’ academic background, the subject areas of the requested articles have also significantly changed, with a remarkable increased requests for articles in medicine and science and technology fields, and a sharp decrease for those in art and humanities, and social sciences. Compared to subject divisions of requested materials from 1999-2001,  requests for articles in arts and humanities decreased from 48.1% to 14.3%. The percentage of articles in social sciences also dropped, from 36.2% to 12.9%. On the other hand, request for articles in other subject areas significantly increased, especially those in medicine, and science and technology. As indicated by Table IV, from 2003-2005,  a total of 1921 filled requests were originated from United States, out of which 922 requests were made for articles in science and technology field, averaging 48% of the total US-based requests. On the other hand, medical journal articles published outside of China seem to be very hot among Chinese scholars. Out of a total of 2822 requests sent by Chinese partner libraries, 1606 (56.9%) requests were for western medical journal articles, especially those in biomedicine and gene engineering. New subject areas also emerge, such as business and law, amount to 3.1% and 1.2% on average for each.
The new trend in document delivery requests is no surprise, given China’s recent development in science and technology, and China’s eagerness to join the international community and conform to international standards in business and legal system. On the other hand, it also reflects the acquisition and holdings of medical science information and resources in China and the United States. A majority of the articles in medical journal are supplied by the Health Sciences Library System of the University of Pittsburgh, which includes the Falk Library of Health Sciences, and the Western Psychiatric Institute & Clinic Library. 
Table IV  Subject divisions of filled requests
Subject	2003-2005	1999-2001*	
	US-based	Partner Lib	Total	US-based	
ArtHum	429 (22.3)	249 (8.9)	678 (14.3)	1,305 (48.1)	
Business	27 (1.4)	119 (4.2)	146 (3.1)	11 (0.4)	
Law	16 (0.8)	42 (1.5)	58 (1.2)	0	
Medicine	295 (15.4)	1606 (56.9)	1901 (40.1)	0	
SciTech	922 (48)	441 (15.6)	1363 (28.7)	414 (15.3)	
SocSci	232 (12.1)	365 (12.9)	597 (12.6 )	981 (36.2)	
Total	1921 (100)	2822 (100.0)	4743 (100.0 )	2,711 (100.0)	

*Note: Statistics for 1999-2001 are based on Xu & Pang’s study, 2003.

2.5	Type of Use of Requested Articles

Similar to Xu and Pang’s study, a majority of the requested articles over the last three years were for scholarly research. Out of  the 850 requests originated within US that have complete information on purpose of  request, 90.4% were to be used for scholarly research. Similar situation exists with requests originated from the Chinese partner libraries. Out of the 653 requests that indicated purpose of request, 77.9% belong to the research category. Another main purpose of request is for dissertation research, which seems to be common for both US-based requests and requests via partner libraries. Table V offers details of patrons’ purpose for requesting the materials based on identifiable data from 2003-2005.

Table V Type of use of requested materials

Purpose	US-Based	Partner Libraries	
	2003	2004	2005	Total	%	2003	2004	2005	Total	%	
Class paper 		4	10	14	1.6		6	1	7	1.1	
Other	1	2	7	10	1.2		6	1	7	1.1	
Research		174	595	769	90.4		177	332	509	77.9	
Teaching		12	6	18	2.1			1	1	0.1	
Dissertation		8	32	40	4.7		88	41	129	19.8	
Grand Total	1	200	650	851	100.0	0	277	376	653	100.0	

1.	The Effectiveness of the Center’s Overall Performance 

Several criteria have traditionally been used to evaluate and indicate the effectiveness of interlibrary loan and document delivery services, including, but not limited to the general rate of filling the filed requests, the turnaround time for requests to be filled, and the evaluations and feedbacks from users (Jackson 1997, Xu & Pang, 2003). We are using all of the three indicators. In addition, comparative review and study of the performance of Chinese partner libraries and libraries within the University of Pittsburgh Library System will be conducted in order to find out limitations and directions for future improvement.

3.1	Fill rate

The center’s performance from January 2003 to December 2005 is summarized in Table VI. In three years, the center received a total of 5922 requests, among which 556 requests were referred to the requesters’ local interlibrary loan services because WorldCat indicates the requested materials are collected by one or more institutions in the United States, therefore did not fall into the center’s service guideline. Because of this reason the number of refer is not counted as unfills. Rather we subtracted it from the total request number to get the number of processed requests. The fill rate is the ratio of number of fill to number of processed request.
It is very obvious that the center’s performance is excellent, with an average fill rate of 89.2%, and turnaround time of 4 days, which is significantly higher than the ARL 1999 statistics. Compared to pre-2003 performance summarized in Xu & Pang’s study, the center not only carried on the tradition of excellence service, but also raised it to an even higher level. The average fill rate increased from 83.2% to 89.2%, and the average turnaround time decreased from 7.75 day to 4 days (Xu & Pang, 2003).
Table VI  Summaries of requests received and filled, with average turnaround time

Year	number of
 requests	number of refer	number of processed requests	number of unfill
	number 
of fill	average
 fill rate %	Average turnaround time (by day)	
2003	2063	292	1771	240	1531	86.4	4.8	
2004	1690	137	1553	131	1422	91.6	3.7	
2005	2169	127	2042	209	1833	89.8	3.6	
Total	5922	556	5366	580	4786	89.2	4	

Table VI also shows that in 2004 the center achieves the highest fill rate (91.6%), in 2005, the second (89.2%), and in 2003, the lowest (86.4%), with the highest number of refer and unfills. This is because some first-time users of the center’s service did not know clearly about the center’s service guideline – only providing academic journal articles that are NOT available in ANY U.S. institutions. 
The unfilled requests were contributed by several factors, the most important of which was because the requested materials do not fall into the criteria that the partner libraries use for document delivery. The center operates strictly under the copyright law of the United States and the People’s Republic of China. We respect and follow partner libraries’ service guidelines and discretion on providing rare and brittle materials. Statistic analyses of the 580 unfilled requests indicate that 346 of them (59.7% ) could not be provided because partner libraries did not think they were interlibrary loanable. Another significant factor is citation error (23.3%). 135 requests were not filled because the citations were wrong, and when the center’s staff tried to contact the requester to verify, there was no response. However, 87 requesters (15%)responded and cancelled the requests by themselves. Table VII gives details on reasons for unfills on yearly basis.

Table VII  Reasons for unfilled requests

Reasons for unfill	2003	2004	2005	Grand Total	
	request	%	request	%	request	%	request	%	
Partner can not provide	198	82.5	100	76.3	48	23.0	346	59.7	
Requester cancelled	4	1.7	5	3.8	78	37.3	87	15.0	
citation error	38	15.8	20	15.3	77	36.8	135	23.3	
ILL can not provide		0.0	6	4.6	6	2.9	12	2.1	
Grand Total	240	100.0	131	100.0	209	100.0	580	100.0	

4. Comparative Study between Performance of Chinese Partner Libraries and the GSC 

Upon the center’s establishment in 1999, four university libraries in mainland China, one in Hong Kong, and one in Taiwan were the pioneering  partner libraries. They were: Peking University (PKU), Tsinghua University (THU), Shanghai Jiaotong University(SHJT), Shanghai Fudan University (SHFD), Chinese University of Hong Kong (CUHK), and Fu Ssu-nien Library of Academia Sinica (FSN). From 2003 to 2005, with the participation of Wuhan University (WHU), Nanjing University (NJU),  Sichuan University (SCU), Zhejiang University (ZJU),  Zhongshan University (ZSU), and the Information Center, Chinese Academy of Sciences (LCAS), the center’s partnership network  increased to twelve, greatly enhanced its geographic distribution and subject coverage. 
Different from the initial three years, the center’s cooperation with the Chinese participating libraries has become truly reciprocal since 2002. On the one hand, the center depends on the Chinese partners to provide Chinese academic journal articles for researchers outside of China. On the other hand, it also began to provide partner libraries with  articles in Western languages that are not available in China. Both sides became requesters and suppliers. A comparison of both sides in terms of subject strength when fulfilling the requests and turnaround time will be conducive to further reflections on the implications of the gateway service model on collection development and resource sharing for libraries in China and the United States.
4.1  Subject Strength of Partner Libraries
As discussed in 2.1.4, an interesting trend in the subject divisions of requested materials over the past three years is the sharp increase of articles in science and technology field for US users, and for Chinese scholars, articles in medical journals. Table VIII and Table IX give details on how these requests are filled by libraries on both sides. Consistent with the filed requests, the largest number of requests that have been successfully supplied is those in science and technology fields, averaging 56%. 
From Table VIII we can immediately spot a new and significant player who supplied 597 articles, accounting for 42.5% of the total requests filled by partner libraries. That is Wuhan University Library (WHU), a Chinese partner that joined the exchange network in 2002.  Another major supplier is the Chinese University of Hong Kong (CUHK), delivered 369 articles from 2003-2005, accounting for 26.6% percent of total filled requests. It is also the only partner among the six initial participating libraries whose delivery rate increased from the previous period (1999-2001), from 18.9% to 26.6% (Xu & Pang, 2003).  Table VIII also indicates both WHU and CUHK have a well-balanced collection in various subject fields, especially the collections in science and technology fields. It should be pointed out that although Tsinghua University and Shanghai Jiaotong University are primarily science and engineering institutions, they did not supply most of the articles in science and technology fields. This does not necessarily mean they do not carry such journals in their collection. Access speed and response time to requests may have influenced the selection of the libraries for delivering requested articles.
 Table VIII  Subject division of requests filled by partner libraries
Article Supplier	ArtHum	Business	Law	Medicine	SciTech	SocSci	Grand Total	
CUHK	44		2	54	248	21	369 (26.3)	
FSN	13	2	1	5	5	5	31 (2.2)	
LCAS	55	10	1	5	5	22	98 (7.0)	
NJU					1		1 (0.1)	
PKU	17			1	12	6	36 (2.6)	
SHFD	94	1	1	31	104	15	246 (17.5)	
SHJT	2				9	1	12 (0.9)	
THU	3			2	9		14 (1.0)	
WHU	52	1	3	109	390	42	597 (42.5)	
Grand Total	280( 20 )	14  (1 )	8 ( 0.9 )	207 ( 15 )	783 ( 56 )	112 ( 8 )	1404 (100.0)	

4.2  Subject Strength of Collections at the University of Pittsburgh
A majority of the requests from the partner libraries were filled by libraries and collections at the University of Pittsburgh. Table IX indicates that out of 2211 partner-based requests that were filled by the center, only 313 were obtained through interlibrary loan department, all other 1898 requests were filled locally, by libraries and collections within University of Pittsburgh. It is remarkable that out of the 1189 requests for articles in medicine field, 995 were filled by the University of Pittsburgh’s Falk Library of Health Science, and the Library of the Western Psychiatric Institute and Clinic (WPIC). In all, Falk filled 996 requests, accounting for 45% of the total partner –based requests, which is a convincing indicator of the excellent teaching and research quality in medical science at the University of Pittsburgh Medical Center, and the collection strength of the University Health Science Library System.
Table IX  Subject division of partner-based requests filled by University of Pittsburgh

Pitt Lib*	ArtHum	Business	Law	Medicine	SciTech	SocSci	Grand Total (%)	
BUSI	 	38	1	 	 	11	50 ( 2.3 )	
CHEM	 	 	 	3	37	 	40 ( 1.8 )	
EAL	53	2	 	10	11	48	124 ( 5.6 )	
ENGI	 	 	 	 	50	 	50 ( 2.3 )	
FALK	1	 	 	968	23	4	996 ( 45.0 )	
FRICK	5	 	 	 	 	 	5 ( 0.2  )	
GSPIA	1	2	1	 	3	10	17 ( 0.8 )	
HILL	154	9	6	20	27	126	342 ( 15.5 )	
ILL 	29	24	 	115	93	52	313 ( 14.2 )	
INFO	 	 	 	 	1	3	4 ( 0.2 )	
LANG	1	 	 	29	8	2	40 ( 1.8 )	
LAW	 	1	26	 	 	1	28 ( 1.3 )	
MATH	3	 	 	 	39	 	42 ( 1.9 )	
PHYSICS	 	 	 	3	21	 	24 ( 1.1 )	
STOR	18	7	1	14	41	21	102 ( 4.6 )	
WPIC	4	 	 	27	2	1	34 ( 1.5 )	
Total
( % )	269
( 12.2 )	83
( 3.8 )	35
( 1.6 )	1189
( 53.8 )	356
( 16.1 )	279
( 12.6 )	2211
( 100 )	

* Library Collections at the University of Pittsburgh

BUSI	Business Library 
CHEM	Chemistry Library 
EAL	East Asian Library
ENGI	Bevier Engineering Library 
FALK	Falk Library of the Health 	Sciences
FRICK	Frick Fine Arts Library 
GSPIA	GSPIA/Economics Library 
HILL	Hillman Library 
ILL 	Interlibrary Loan 
INFO		Information Sciences Library 
LANG	Langley Library 
LAW	Barco Law Library 
MATH	Mathematics Library 
PHYSICS	Physics Library
STOR	Library Resource Facility
WPIC		Library of the Western Psychiatric Institute and Clinic

4.3 Turnaround Time
The center’s enhanced fill rate and turnaround time over the past three years would not have been possible without cooperation and improved services from the Chinese partner libraries. 
With globalization and increased interdependence of nations and countries, many Chinese libraries realized the importance of using resource sharing and document delivery to complement local collection holdings. More and more libraries also realized the importance of timely response and efficiency in supplying the requested materials, hence attracting more users to the service. According to a study on current status and development of document delivery service of 20 large libraries in mainland China, most libraries are committed to a 2-3 day response to a request, 5-7 day turnaround time for supplying the requested materials for domestic users, and 7-14 day for international request (Guo & Yao, 2004). 
The document delivery agreement between the center and the Chinese partner libraries specify similar terms, and in practice, both sides have faithfully carried them out. Table VIII and Table IX offer an overview of the center’s performance in supplying requested materials to Chinese partner libraries and vice versa.
From Table VIII we can see that the center performs superbly well in supplying requested materials to Chinese partner libraries, with an average turnaround time of 3.3 days, which is significantly high by any standard. This is in large part owing to the dedication and professional expertise of the center’s staff. Cooperation from staff at branch libraries within the University Library System is also indispensable to this excellent performance. 
Table IX shows that the average turnaround time from Chinese partner libraries is 5.7 days, which suggests a more efficient service than the period of 1999-2001 when the average turnaround time was 7.75 days, and more than twice faster than the ten US research libraries with the best performance (13.5 days) ( Jackson, 1997; Xu and Pang, 2003).
Table VIII Turnaround time, GSC 
Pitt Lib	Total fills	Total turnaround	Average turnaround	
BUSI	50	63	1.3	
CHEM	39	60	1.5	
EAL	51	204	4.0	
ENGI	51	72	1.4	
FALK	1003	1624	1.6	
FRICK	5	5	1.0	
GSPIA	17	19	1.1	
HILL	331	446	1.3	
ILL	340	4052	11.9	
INFO	4	4	1.0	
LANG	40	47	1.2	
LAW	28	34	1.2	
MATH	39	51	1.3	
PHYSICS	24	37	1.5	
STOR	104	346	3.3	
WPIC	34	48	1.4	
Grand Total	2160	7112	3.3	

Table IX  Turnaround time, partner libraries

Partner Lib	Total fills	Total turnaround	Average turnaround	
CUHK	31	171	5.5	
FSN	98	350	3.6	
LCAS	1	1	1.0	
NJU	49	535	10.9	
PKU	247	2415	9.8	
SHFD	12	39	3.3	
SHJT	15	215	14.3	
THU	369	1612	4.4	
WHU	717	3427	4.8	
Grand Total	1539	8765	5.7	

5. Conclusion
This study offered a comparative review and analysis of the characteristics of both the US-based users and Chinese partner library users, their document request patterns in terms of subject divisions of requested materials over the past three years, and assessed the service of both the Gateway Service Center and the Chinese partner libraries in terms of fill rate and turnaround time. The study reveals some new trends in users’ document delivery request pattern that merit greater attention and further research, such as the increase of users from non-academic settings, the decrease of demands for articles in humanities and social science, the remarkable increase in requests for articles by Chinese scholars on science and technology issues, and the overwhelming demand from Chinese scholars for western medical journal articles and information. Statistic and data analysis also indicates the Gateway Service Center has been consistently playing an important role in global document delivery. Its service and performance offers an excellent case for cross country user studies and service evaluations, as well as further thoughts on global resource sharing.  

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