Presentation on theme: "A ‘best match’ for common search commands: a comparison of searching (CDSR and CENTRAL) via Wiley and Ovid HLG Conference, July 2012 Jenny Craven, Information."— Presentation transcript:
A ‘best match’ for common search commands: a comparison of searching (CDSR and CENTRAL) via Wiley and Ovid HLG Conference, July 2012 Jenny Craven, Information Specialist, NICE Jenny Kendrick, Information Specialist, NICE
Advice on new and existing treatments Clinical guidelines, outcome frameworks and quality standards Health promotion and disease prevention Comprehensive evidence service NICE and NHS Evidence Evidence – guidance – shared learning
Associate Director, 23 Information Professionals, and an Administrator Professional expertise to enable access to high quality information to support the development of guidance Tailored information support for the different Centres and Directorates within NICE Institute-wide corporate information services Guidance Information Services
Purpose of the project As a result of experiencing some issues with the Cochrane Library via Wiley in 2010/11 a project group was set up to look into the differences of searching: –Cochrane Database of Systematic Reviews (CDSR) –Cochrane Central Register of Controlled Trials (CENTRAL) –between the Wiley and Ovid search interfaces
Aims of the project To compare search commands and functionality of Wiley and Ovid, including identifying the ‘best match’ for common search commands between the different interfaces. To identify any discrepancies in the way comparative search commands are executed across the two interfaces. To investigate and explain any discrepancies identified. To compare the performance. To investigate any other issues identified during the project.
Evidence in Literature Inconsistent search commands across various interfaces... –Differences in the way stop words are searched and the use of adjacency (Feinglos, 1983) –Limits and Field searches can differ between interfaces (De Groote, 2000, Allison, 2006) –Text word searches (e.g. ‘All text’ and TX) can produce different numbers of results. (Younger & Boddy, 2008) –Some interfaces assume truncation, some require a wildcard (*) (Younger & Boddy, 2008) Learning the ‘intricacies of individual interfaces and databases is time-consuming’ (Boddy & Younger, 2009)
Methods Detailed cross comparisons were undertaken on the following search functions: -Truncation -Proximity Operators -MeSH terms including exploded MeSH terms; -Free text/All fields, including free text (title, abstract, keyword search) and free text (title, abstract only)
Methods Appropriate terms were selected to explore each of the search functions. Terms were selected from: –existing strategies from Interventional Procedures (IP) and Guideline Review (GR) searches –and, for practical reasons, terms were selected that did not retrieve a large number of results (ideally less than 200 results, although this was not always possible)
Methods Searches were recorded using a Word table, listing the test terms, interface and database, syntax applied, and the number of results. If a large number of results were retrieved, these were imported into Reference Manager to identify unique records for closer inspection in the appropriate database. Where the numbers retrieved were low, records could be inspected directly from within the database.
Search syntax and functionality DatabaseTruncationProximity operators MeSHExp MeSHFree text - All fields Free text - ti, ab, kw/hw Free text – ti,ab OVID CENTRAL *adj3MeSH/Exp MeSH/-ti, ab, hwti, ab or tw 1 OVID CDSR *adj3kwInclude all terms as kw and Or/ together tw 2 ti, ab, kwti,ab 2 Wiley - Cochrane Library *Near or lower proximity e.g. Near/4 MeSH/ 4 MesH explode all trees Search All 3 text (i.e. term with no suffix) ti, ab, kw – includes ‘Plain Language Summary’ ti,ab 1 Preferred free text searching mode for Ovid CENTRAL 2 Preferred free text searching mode for Ovid CDSR (note that.tw is equivalent to full text searching in CDSR) 3 Preferred free text searching mode for Wiley 4 Note: in Wiley check tags (e.g. adult, child, male, female) need to be searched for using.kw
Truncation & Proximity Operators Truncation - Use * in both Ovid and Wiley Proximity Operators –The proximity operators perform differently in Ovid and Wiley. –In Ovid Adj3 refers to three words between search terms and stop words are not included in the count. –In Wiley Near/3 refers to the first search term plus the next two words, and all words are counted (including stop words). –Either use Near in Wiley, or if too many records are retrieved, use a lower proximity e.g. Near/4.
MeSH terms MeSH terms - CDSR –In Ovid use.kw –in Wiley use MeSH MeSH Terms - CENTRAL –Use MeSH/ in Ovid and Wiley
Exploded MeSH Exploded MeSH – CDSR - In Wiley use ‘MeSH explode all trees - In Ovid use.kw and include the main MeSH heading plus the narrower terms Or’d together, for example: MeSH descriptor Labor Onset explode all trees 1.Labor Onset.kw 2.Labor Stage, First.kw 3.Labor Stage, Second.kw 4.Labor Stage, Third.kw 5.OR/1-4 Exploded MeSH – CENTRAL - Use exp MeSH/ in Ovid and Wiley.
Free text/All fields Free text/ All fields - CDSR –Use.tw in OVID –no suffix (all text) in Wiley. –Small differences in retrieval as ‘evidence tables’ and ‘reference list’ text included in a Wiley ‘all text’ search but not included in an Ovid.tw search.
Free text/All fields Free text/ All fields - CENTRAL –In Wiley use no suffix (all text) –There is no option for performing an ‘all text’ search in Ovid CENTRAL.
Free text (ti,ab,kw) Free text (title, abstract, keyword search) - CDSR –Use.ti, ab, kw in both OVID and Wiley. –Small differences in retrieval as ‘plain language summary’ field included in a Wiley.ti,ab,kw search, but not in Ovid.
Free text (ti,ab,kw) Free text (title, abstract, keyword search) - CENTRAL –Use.ti, ab, kw in Wiley. –Use.ti, ab, hw in OVID –The qualifier.hw is used in OVID to ensure retrieval of CENTRAL records indexed with MeSH and non- MESH subject headings (i.e. EMTREE terms). A.kw search in Ovid will only retrieve records indexed with non-MeSH headings.
Free text (ti,ab) Free text (title, abstract) – CDSR –In Ovid and Wiley use.ti,ab. Free text (title, abstract) – CENTRAL –in Wiley use.ti,ab. –In Ovid use.ti,ab or.tw
Other Issues Limits (date and language) Exporting records Multifile searching Currency
Summary and conclusions In summary, it is possible to successfully search CDSR and CENTRAL via Ovid and Wiley. Advantages of Ovid: –Cross-search the CDSR and CENTRAL databases with MEDLINE and EMBASE (multifile searching), and being able to de-duplicate within Ovid. Disadvantages of Ovid: –The study experienced a time delay between the updating of CDSR and CENTRAL in Ovid.
Summary and conclusions Advantages of Wiley: –Cross-search the CDSR and CENTRAL databases with the CRD databases –Only having to create a single strategy to search CDSR and CENTRAL instead of multiple strategies. Disadvantage of Wiley: –Some issues are still being experienced – such as timing out during searches, loss of searches, and displaying incorrect search results
Final comment It should also be noted that there will always be differences in the number of records retrieved by the two interfaces –execution of MeSH headings (CDSR) –fields included in an ‘all text ‘search (CDSR) –proximity operators (CDSR and CENTRAL) The search syntax presented here and in the report simply represent the ‘best match’ between the Ovid and the Wiley interfaces.
Free/Quick plug! Final Report - Cochrane project: a comparison of searching CDSR and CENTRAL via Wiley and Ovid, copies available on request Craven, J., Kendrick, J., and Boynton, J. (2011) Cochrane project: a comparison of searching CDSR and CENTRAL via Wiley and Ovid. Health libraries Group Newsletter, December groups/health/pages/newsletter.aspx groups/health/pages/newsletter.aspx Detailed article is planned for the near future
References Allison, M. (2006) Comparison of CINAHL via EBSCOhost, Ovid, and Pro Quest. Journal of Electronic Resources in Medial Libraries, vol 3(1) pp Craven, J., Kendrick, J., and Boynton, J. (2011) Cochrane project: a comparison of searching CDSR and CENTRAL via Wiley and Ovid. Health libraries Group Newsletter, December interest-groups/health/pages/newsletter.aspxhttp://www.cilip.org.uk/get-involved/special- interest-groups/health/pages/newsletter.aspx De Groote, S. L (2000) PubMed, Internet Grateful Med, and Ovid: a comparison of Three MEDLINE Internet Interfaces. Medical Reference Services Quarterly, Vol 19(4) pp1-13.
References Feinglos, S.J. (1983) MEDLINE at BRS, DIALOG, and NLM: Is There a Choice? Bulletin of the Medical Library Association. 71(1) January. Younger, P. and Boddy, K. (2008) When is a search not a search? A comparison of searching the AMED complementary health database via EBSCOhost, OVID and DIALOG. Health Information and Libraries Journal, 26, pp.126–135 Younger, P. and Boddy, K. (2009) What a difference an interface makes: just how reliable are your search results. Focus on alternative and complimentary therapies Vol 14(1) March, pp5-7.