Schell Mary Beth
UNC Chapel Hill Health Sciences Library/CB # 7585, Chapel Hill, NC 27599, USA.
Biomed Digit Libr. 2006 Sep 6;3:9. doi: 10.1186/1742-5581-3-9.
The North Carolina (NC) Area Health Education Center's (AHEC) Digital Library (ADL) is a web portal designed to meet the information needs of health professionals across the state by pulling together a set of resources from numerous different sources and linking a pool of users to only the resources for which they have eligibility. Although the ADL was designed with the primary purpose of linking health care professionals to a set of licensed resources, the ADL also contains a significant number of links to free resources. These resources are available to any ADL member logging into their ADL account and to guest visitors to the ADL. While there are regular assessments of the subscription resources in the ADL as to utility and frequency of use, up until this point there has been no systematic analysis of the use of the overall set of free resources. It was decided to undertake an examination of the usage of ADL free resources over a 6-month period to analyze the utility of these resources to both ADL members and guests.
Each time a resource is accessed through the ADL, it is logged in a table. This study used a SQL query to pull every free resource accessed between November 1, 2005 and April 30, 2006. An additional query also pulled the user information for each free resource accessed. Once the queries of the database were complete, the results were imported into an Excel spreadsheet and analyzed using basic descriptive statistics.
The vast majority of resource use through the ADL is to licensed resources. There are 2056 free resource URLs in the ADL, to which 1351 were linked out, meaning there was at least one link out to 65% of the free resources. The single most popular free resource was PubMed with 4803 link outs or nearly 20% of the total link outs to free resources. The breakdown of free resource use by different use groups indicates that the highest percentage of use of free resources was by guests followed by institutional affiliates and AHEC Faculty/Staff. The next 3 highest user groups accessing free resources are: paid members, preceptors, and residents.
The only free resource capturing a significant number of link outs is the free link to PubMed. This reflects the importance placed on traditional medical literature searching by the ADL clinical user base. Institutional affiliates access free resources through the ADL with the second highest frequency of all the user groups. Finally, in analyzing use of free resources, it is important to note the overall limitations of this survey. While link outs are excellent indicators of frequency of use they do not provide any information about the ultimate usefulness of the resource being accessed. Further studies would need to examine not only the quantitative use of resources, but also their qualitative importance to the user.
北卡罗来纳州（NC）地区卫生教育中心（AHEC）数字图书馆（ADL）是一个门户网站，旨在通过整合来自众多不同来源的一系列资源，并将用户群体仅链接到他们有权限访问的资源，来满足该州卫生专业人员的信息需求。尽管ADL的主要设计目的是将医疗保健专业人员链接到一组有许可证的资源，但ADL也包含大量指向免费资源的链接。这些资源可供任何登录其ADL账户的ADL成员以及ADL的访客使用。虽然对ADL中的订阅资源的实用性和使用频率进行了定期评估，但到目前为止，尚未对整个免费资源集的使用情况进行系统分析。因此决定对ADL免费资源在6个月期间的使用情况进行调查，以分析这些资源对ADL成员和访客的实用性。
每次通过ADL访问资源时，都会记录在一个表中。本研究使用SQL查询来提取2005年11月1日至2006年4月30日期间访问的每一个免费资源。另一个查询还提取了每个访问的免费资源的用户信息。一旦数据库查询完成，结果就会导入到Excel电子表格中，并使用基本描述性统计进行分析。
通过ADL使用的资源绝大多数是有许可证的资源。ADL中有2056个免费资源URL，其中1351个有链接指向外部，这意味着至少有一个链接指向65%的免费资源。最受欢迎的单个免费资源是PubMed，有4803个链接指向外部，占免费资源总链接数的近20%。不同用户群体对免费资源的使用情况细分表明，免费资源使用比例最高的是访客，其次是机构附属人员和AHEC教职员工/工作人员。访问免费资源的接下来三个最高用户群体是：付费会员、带教老师和住院医师。
唯一获得大量链接指向外部的免费资源是指向PubMed的免费链接。这反映了ADL临床用户群体对传统医学文献检索的重视程度。机构附属人员通过ADL访问免费资源的频率在所有用户群体中排名第二。最后，但在分析免费资源的使用情况时，重要的是要注意这项调查的总体局限性。虽然链接指向外部是使用频率的优秀指标，但它们没有提供任何关于所访问资源最终有用性的信息。进一步的研究不仅需要检查资源的定量使用情况，还需要检查它们对用户的定性重要性。
