Online tables of contents for books: effect on usage

Objectives: To explore whether the presence of online tables of contents (TOC) in an online catalog affects circulation (checkouts and inhouse usage). Two major questions were posed: (1) did the presence of online tables of contents for books increase use, and, (2) if it did, what factors might cause the increase? Method: A randomized and stratified design was used in tracking usage of 3,957 book titles that were previously divided into two groups: one with TOC and one without TOC. Stratification was done for year of imprint, location, subject, previous use, circulating or non-circulating status, and presence of TOC. The use was tracked by the online catalog statistics in the InnoPac online catalog for fourteen months. Results: The study found that tables of contents do increase usage. It also showed a correlation in the size of the effect based on the currency of the titles. In general, even after adjusting for all of the variables (publication date, location, circulation status, subject, and previous use), the odds of a title being used increased by 45% if the titles had online tables of contents, a statistically significant impact at the 0.05 level. Conclusions: This case-control study presents new information about the impact on circulation and inhouse use when tables of contents for books are added to the online catalog record. The study helps to establish the positive role of tables of contents in online catalogs. The research establishes TOC as a major parameter that can be successfully studied using quantitative methods. The study also provides information professionals with some guidance on when enhancement of TOC is likely to be most effective in increasing the use of existing collections.

研究目的：探讨在线图书馆目录中的图书在线目录（Table of Contents，TOC）是否会对文献流通（外借与馆内阅览量）产生影响。本研究提出两项核心问题：其一，图书的在线目录是否确实提升了文献使用率？其二，若确有此效果，哪些因素可能驱动了使用率的增长？
研究方法：采用随机分层设计，对3957种预先分为两组的图书开展使用量追踪：一组配备在线目录，另一组未配备。分层维度涵盖出版年份、馆藏地点、学科分类、既往使用量、流通属性（可外借/不可外借）以及是否带有在线目录。研究借助InnoPac在线目录的统计数据，开展了为期14个月的使用追踪。
研究结果：本研究证实，在线目录确实能够提升文献使用率，且该效果的强弱与图书的时效性存在相关性。总体而言，即便在校正所有变量（出版日期、馆藏地点、流通属性、学科分类与既往使用量）后，带有在线目录的图书被使用的几率提升了45%，该结果在0.05显著性水平下具有统计学意义。
研究结论：本对照研究首次揭示了为在线图书馆目录添加图书目录对文献流通与馆内阅览量的影响，证实了在线目录在图书馆目录体系中的积极作用，确立了TOC作为可通过定量方法开展有效研究的核心参数之一。此外，本研究还为信息从业者提供了实践指导，有助于判断在何种场景下优化在线目录功能可最有效地提升馆藏资源的使用率。