Methods for estimating the number of relevant documents in a collection

Several statistical sampling methods are evaluated for estimating the total number of relevant documents in a collection for a given query. The total number of relevant documents is needed in order to compute recall values for use in evaluating document retrieval systems. The simplest method considered uses simple random sampling to estimate the number of relevant documents. Another type of random sampling, which assigns unequal selection probabilities to the individual documents in the collection, is also investigated. An alternative approach considered uses curve fitting and extrapolation, where a smooth curve is developed which relates precision to document rank. Another curve relates a function of precision to the query-document score. In either case, the curve is extrapolated to the total number of documents in order to estimate the number of relevant documents. Empirical comparisons are made of all three methods.     

Off-Campus Term: A setting for therapeutic intervention

Experiential education has served as a setting for therapeutic intervention in treatment of a communications handicapped young adult. This paper reports how newly learned communications skills were successfully applied in an off-campus setting and were subsequently carried over to campus and home.     

Marketing the hospital library

Many librarians do not see themselves as marketers, but marketing is an essential role for hospital librarians. Library work involves education, and there are parallels between marketing and education as described in this article. It is incumbent upon hospital librarians actively to pursue ways of reminding their customers about library services. This article reinforces the idea that marketing is an element in many of the things that librarians already do, and includes a list of suggested marketing strategies intended to remind administrators, physicians, and other customers that they have libraries in their organizations.     

The value and impact of information provided through library services for patient care: a systematic review

OBJECTIVE: An updated systematic review was carried out of research studies looking at the value and impact of library services on health outcomes for patients and time saved by health professionals. METHODS: A comprehensive systematic search was undertaken of the published literature to September 2003 in ERIC, LISA, MEDLINE, PREMEDLINE, EMBASE, the Cochrane Controlled Trials Register and Google. Some handsearching was carried out, reference lists were scanned and experts in the field were contacted. Twenty-eight research studies of professionally led libraries for health-care staff, including clinical librarian projects, met the inclusion criterion of at least one health or 'time saved' outcome. Papers were critically appraised using internationally accepted criteria. Data were extracted and results were summarised using a narrative format as the studies were heterogeneous and precluded a statistical analysis. RESULTS: There is evidence of impact from both traditional and clinical librarian services. The higher quality studies of traditional services measured impacts of 37-97% on general patient care, 10-31% on diagnosis, 20-51% on choice of tests, 27-45% on choice of therapy and 10-19% on reduced length of stay. Four studies of clinical librarian projects suggested that professionals saved time as a result of clinical librarian input, and two of these studies showed evidence of cost-effectiveness. However, the clinical librarian studies were generally smaller, with poorer quality standards. CONCLUSIONS: Research studies suggest that professionally led library services have an impact on health outcomes for patients and may lead to time savings for health-care professionals. The available studies vary greatly in quality but the better quality studies also suggest positive impacts. Good practice can be gathered from these studies to guide the development of a pragmatic survey for library services that includes the direct effects for patients among the outcome measures.