Evidence-based librarianship: an overview.

OBJECTIVE: To demonstrate how the core characteristics of both evidence-based medicine (EBM) and evidence-based health care (EBHC) can be adapted to health sciences librarianship. METHOD: Narrative review essay involving development of a conceptual framework. The author describes the central features of EBM and EBHC. Following each description of a central feature, the author then suggests ways that this feature applies to health sciences librarianship. RESULTS: First, the decision-making processes of EBM and EBHC are compatible with health sciences librarianship. Second, the EBM and EBHC values of favoring rigorously produced scientific evidence in decision making are congruent with the core values of librarianship. Third, the hierarchical levels of evidence can be applied to librarianship with some modifications. Library researchers currently favor descriptive-survey and case-study methods over systematic reviews, randomized controlled trials, or other higher levels of evidence. The library literature nevertheless contains diverse examples of randomized controlled trials, controlled-comparison studies, and cohort studies conducted by health sciences librarians. CONCLUSIONS: Health sciences librarians are confronted with making many practical decisions. Evidence-based librarianship offers a decision-making framework, which integrates the best available research evidence. By employing this framework and the higher levels of research evidence it promotes, health sciences librarians can lay the foundation for more collaborative and scientific endeavors.

Evidence-based librarianship: searching for the needed EBL evidence.

This paper discusses the challenges of finding evidence needed to implement Evidence-Based Librarianship (EBL). Focusing first on database coverage for three health sciences librarianship journals, the article examines the information contents of different databases. Strategies are needed to search for relevant evidence in the library literature via these databases, and the problems associated with searching the grey literature of librarianship. Database coverage, plausible search strategies, and the grey literature of library science all pose challenges to finding the needed research evidence for practicing EBL. Health sciences librarians need to ensure that systems are designed that can track and provide access to needed research evidence to support Evidence-Based Librarianship (EBL).

Characteristics of peer reviewed clinical medicine journals.

Many variations exist in editorial peer review practices in clinical medicine journals. These practices will become more crucial as medical journals make more of their contents available via the World Wide Web. This paper explores five fundamental dimensions of editorial peer review variations: (1) the extent to which manuscripts are subjected to peer review; (2) the sequence of decision points in the peer review process; (3) blinding practices; (4) acceptance rates for submitted manuscripts; and (5) guidelines stating editors' expectations of reviewers. Variations in editorial peer review practices make it difficult to define a "peer reviewed journal" in clinical medicine. Research in this relatively new area of inquiry has not established the relative strengths of each variation in relation to a journal's quality.

The vital few meet the trivial many: unexpected use patterns in a monographs collection.

PURPOSE: To test three related hypotheses about monographs circulation at academic health sciences libraries: (1) Juran's "Vital Few" Principle, sometimes incorrectly referred to as the "Pareto Principle"; (2) most (> 30%) new monographs will not circulate within four years; and, (3) Trueswell's 20/80 rule concerning intensity of monographs circulation. METHODS: Retrospective circulation study conducted at a major academic health sciences library in November 1997 on monographs acquired during 1993, utilizing an online review file. RESULTS: Unexpectedly, most monographs (84%) had circulated at least once in the four years following acquisition. Combining circulation and in-house data revealed that 90.7% of the monographs acquired in 1993 had been used at least once. Small percentages of these monographs produced disproportionately high circulation levels. CONCLUSION: Monographs circulation rates confirm Juran's Vital Few principle. Most monographs circulated at least once in contrast to results reported by the Pittsburgh Study or other studies reported by Hardesty and Fenske. The results do not comply with Trueswell's 20/80 ratio rule. Further research needs to investigate the effects of low students to books ratios and problem-based learning (PBL) curricula upon monographs utilization.

The roles of library liaisons in a problem-based learning (PBL) medical school curriculum: a case study from University of New Mexico.

The relationships between problem-based learning (PBL) curricula and libraries have generated a substantial number of journal articles, but few have addressed the importance of the interaction between health science libraries and PBL curricula. This article attempts to contribute to this dimension through a description of the roles of library liaisons. First we describe the evolution of the liaison roles beginning 2 years prior to the implementation of a PBL curriculum. We then describe the core responsibilities of liaisons at the University of New Mexico (UNM) with mention of other innovative roles developed by some liaisons.

Identifying peer-reviewed journals in clinical medicine.

BACKGROUND: Two directories that contain information about serials also offer lists of thousands of journals identified as peer-reviewed. Librarians generally regard these lists as authoritative. OBJECTIVE: To identify clinical medicine journals on both peer-reviewed lists, measure the extent of discrepancies between these two lists, and determine the cause for these discrepancies. DESIGN: Comparison study. MEASUREMENTS: The extent of the discrepancies were tallied once the author had attempted to control for all extraneous variables. Interviews with the editorial staffs of each directory in regard to procedures for compiling the directories did not produce an explanation for these discrepancies. RESULTS: Nearly half (46%) of the 784 clinical medicine journals were unique to either one directory's list of peer-reviewed journals or the other's, indicating significant discrepancies between the two directories. Specifically, The Serials Directory listed 211 (27%) unique titles and Ulrich's International Periodicals Directory listed 150 (19%) unique titles (total unique titles = 46%). Both directories listed 423 of the same titles (54%). CONCLUSION: Widespread confusion about the actual identities of peer reviewed clinical medicine journals appears to explain the discrepancies between lists in these two periodical directories.

The small aortic root and the Medtronic Hall valve: ultrafast computed tomography assessment of left ventricular mass following aortic valve replacement.

BACKGROUND AND AIMS OF THE STUDY: The selection of an appropriate size aortic valve substitute with respect to patient size and life-style, in the presence of a small aortic root, is problematic, and a decision to enlarge the aortic annulus is often arbitrary. An aortic valve substitute-patient mismatch may place an excessive load on the left ventricle resulting in residual left ventricular mass with attendant patient morbidity and mortality. The aim of this study was to assess the adequacy of the Medtronic Hall valve in the small aortic root using ultrafast computed tomography analysis of left ventricular mass. MATERIALS AND METHODS: In 13 patients the smallest Medtronic Hall valves (size 20 and 21; measured internal orifice area of 2.01 cm2 for both) were used to replace the native aortic valve. All patients had aortic stenosis, and left ventricular hypertrophy was established by echocardiography. The mean body surface area was 1.8 +/- 0.2 m2 (range 1.50-2.06 m2) and the mean weight was 75 +/- 15 Kg (range 50-97 Kg). The mean preoperative New York Heart Association functional class was 3.54 +/- 0.5. RESULTS: There was no operative or late mortality. At a mean follow up of 22 months after aortic valve replacement, the mean left ventricular mass index was 89 +/- 11.4 g/m2 (normal left ventricular mass index by ultrafast computed tomography = 97 +/- 14 g/m2) and mean New York Heart Association functional class was 1.6 +/- 0.8 (p (Binomial) = 0.0001 compared to preoperative). Doppler echocardiogram demonstrated a mean gradient across the prosthetic valve of 17 +/- 7 mmHg. There was no trend towards greater left ventricular mass index in patients with greater body surface area or weight. In no patient was the aortic annulus enlarged. CONCLUSIONS: Trends from this preliminary data suggest that implanting the smallest Medtronic-Hall aortic valves (sizes 20 and 21) results in normal left ventricular mass following aortic valve replacement in patients up to a body surface area of 2.06 m2 and provides support for the notion that an aortic annulus enlarging procedure was not necessary in this group of patients.

Accuracy of indexing coverage information as reported by serials sources.

This article reports on the accuracy of indexing service coverage information listed in three serials sources: Ulrich's International Periodicals Directory, SERLINE, and The Serials Directory. The titles studied were randomly selected journals that began publication in either 1981 or 1986. Aggregate results reveal that these serials sources perform at 92%, 97%, and 95% levels of accuracy respectively. When the results are analyzed by specific indexing services by year, the performance scores ranged from 80% to 100%. All three serials sources tend to underreport index coverage. The author advances five recommendations for improving index coverage accuracy and four specific proposals for future research. The results suggest that, for the immediate future, librarians should treat index coverage information reported in these three serials sources with some skepticism.

A problem-based learning curriculum in transition: the emerging role of the library.

This case study describes library education programs that serve the University of New Mexico School of Medicine, known for its innovative problem-based learning (PBL) curricular track. The paper outlines the specific library instruction techniques that are integrated into the curriculum. The adaptation of library instruction to a PBL mode of medical education, including the use of case studies, is discussed in detail. Also addressed are the planning processes for the new PBL curriculum scheduled for implementation in 1993, including the activities of library faculty and staff and the probable new role of the library in the new curriculum.

Nucleic acid hybridization assays employing dA-tailed capture probes. I. Multiple capture methods.

A quantitative hybridization assay termed "reversible target capture" is described. The technique is designed to extensively purify the target nucleic acid from crude cell lysates in about 1 h without phenol extraction. Simple, rapid methods are described that explain how each process in the assay is optimized. The procedure involves hybridizing the target nucleic acid in solution with a dA-tailed capture probe and a labeled probe. The capture probe-target-labeled probe "ternary complex" is then captured on magnetic beads containing oligo(dT). After the excess unhybridized labeled probe, cell debris, and other sample impurities are washed away, the intact ternary complex is further purified by chemical elution from the beads and recapture on fresh beads. The ternary complex is then eluted thermally and recaptured on a third set of beads or on poly(dT) filters. This triple capture method results in a detection limit of approximately 0.2 amol (100 fg) of target with 32P-labeled riboprobes. This is approximately 1000 times more sensitive than sandwich assays employing only a single capture step. The method is illustrated by detecting Listeria cells in the presence of heterologous bacteria. With three rounds of target capture, as few as six Listeria cells have been detected in the presence of 1.25 x 10(7) control cells.

Right to left interatrial shunting following balloon mitral valvuloplasty.

A complication of balloon mitral valvuloplasty is development of left-to-right interatrial shunt. This report describes right-to-left interatrial shunting following balloon mitral valvuloplasty in a patient with mitral stenosis, tricuspid regurgitation and pulmonary hypertension.

Effect of residence in a fluoridated community on the incidence of coronal and root caries in an older adult population.

Eighteen-month caries incidence among older adult residents of fluoridated and nonfluoridated communities was compared. Rates for both coronal and root caries were consistently lower among long-term residents of the fluoridated communities than among life-long residents of nonfluoridated communities. Coronal caries incidence was significantly lower for people who had resided in fluoridated communities for more than 30 years (1.95 vs 1.33 surfaces). Root caries incidence was significantly less among residents for more than 40 years (0.56 vs 1.11 surfaces). Fluoridation appeared to be beneficial for the older adults examined, even though the exposure to fluoridated water began in adulthood.

Immunological capture of nucleic acid hybrids and application to nonradioactive DNA probe assay.

Antibodies specific for DNA:RNA hybrids were coated onto polystyrene test tubes and applied to hybridization assays involving DNA and RNA. Synthetic DNA probes complementary to 16S rRNA of Campylobacter were labeled with biotin and hybridized to ribosomal RNA directly in lysates of bacterial cells. After hybridization, DNA:RNA hybrids were captured with immobilized anti-DNA:RNA antibody, and the biotinylated probe was detected with streptavidin-horseradish peroxidase (EC 1.11.1.7) conjugate. The assay was optimized to detect as few as 70,000 Campylobacter cells in a sample. We compared the utility of this hybridization assay with that of conventional microbiology methods by examination of 1448 stool samples from hospital clinical laboratories. The DNA hybridization assay had a sensitivity of 98.7% (75/76) and a specificity of 98.2% (1347/1372) and overall agreed with 98.2% of the conventional results for a test population that had a 5.2% incidence (76/1448) of Campylobacter infection. The assay is simple to perform and yields results within 2.5 h.

Total synthesis and cloning of a gene coding for the ribonuclease S protein.

A gene for ribonuclease S protein, has been chemically synthesized and cloned. The gene is designed to have 25 specific restriction endonuclease sites spaced at short intervals, permitting its structure to be rapidly modified. This flexibility facilitates tests of hypotheses relating the primary structure of the enzyme to its physical and catalytic behavior.