The Cochrane Library

Transcription

1 The Cochrane Library Introduction The Cochrane Library is an electronic information service designed to provide evidence to inform health care decision-making. Updated monthly, it is a useful source of answers to questions about the effectiveness of treatments, e.g. Are there any systematic reviews of stroke rehabilitation effectiveness? Is there evidence that ACE inhibitors are better than other drugs for hypertension? What strategies for smoking cessation are most effective? Please note that it does not provide answers to general healthcare questions, e.g. Do women like the idea of HRT? What are the effects on health of unemployment? Primary research other than randomised controlled trials and controlled clinical trials is excluded as are clinical guidelines and needs assessment studies. The Cochrane Library is the best single source of reliable clinical evidence. If you find a systematic review that answers your question, you will be saved the work of searching databases for journal articles, as well as all the reading involved. Connecting to the Cochrane Library 1. The Cochrane Library is available on the worldwide web at 2. There is a link to the Cochrane Library in the A-Z list of databases available from LJMU s Electronic Library page The main databases in the Cochrane Library The Cochrane Database of Systematic Reviews (CDSR) This is probably the most useful part of the Cochrane Library for most people. A systematic review identifies an intervention for a specific disease or other problem in health care, and determines whether or not this intervention works. To do this authors locate, appraise and synthesise evidence from as many relevant scientific studies as possible. They summarise conclusions about effectiveness, and provide a unique collation of the known evidence on a given topic, so that others can easily review the primary studies for any intervention. Systematic reviews differ from other types of review in that they adhere to a strict design in order to make them more comprehensive, LIBRARY SERVICES

2 thus minimising the chance of bias, and ensuring their reliability. Systematic reviews are of two types: full reviews and protocols. Protocols are reviews in progress. The CDSR is updated monthly. The systematic reviews published are revised as new research results become available or as errors are identified. The Cochrane Central Register of Controlled Trials (CENTRAL) The Cochrane Central Register of Controlled Trials (CENTRAL) includes details of published articles taken from bibliographic databases (notably MEDLINE and EMBASE), and other published and unpublished sources. CENTRAL records include the title of the article, information on where it was published (bibliographic details) and, in many cases, a summary of the article. They do not contain the full text of the article. About 60% of the records in CENTRAL are taken from Medline. Also, each Cochrane Review Group maintains and updates a collection of controlled trials relevant to its own area of interest, these are called Specialized Registers. Each Cochrane Review Group may also collect items that are not relevant to its own field of interest; these are known as Handsearch Results. All Cochrane Review Groups Specialized Registers, the Handsearch Results register, relevant records retrieved from MEDLINE, and relevant records retrieved from EMBASE, are merged and published as CENTRAL. To search CENTRAL individually, click on the Trials button on the tool bar across the top of the Cochrane Library home page and click on Search trials (CENTRAL). The Database of Abstracts of Reviews of Effects (DARE) This is the only database to contain abstracts of systematic reviews that have been qualityassessed. Each abstract includes a summary of the review together with a critical commentary about the overall quality. DARE is a key resource for busy decision-makers and can be used for answering questions about the effects of specific interventions, whether such questions arise from practice or when making policy. DARE covers a broad range of health related interventions and thousands of abstracts of reviews in fields as diverse as diagnostic tests, public health, health promotion, pharmacology, surgery, psychology, and the organization and delivery of health care. DARE complements the CDSR by quality-assessing and summarizing reviews that have not yet been carried out by The Cochrane Collaboration. DARE is produced by the Centre for Reviews and Dissemination (CRD) at the University of York, UK. Health Technology Assessment Database (HTA) This brings together details of completed and ongoing health technology assessments (studies of the medical, social, ethical, and economic implications of healthcare interventions) from around the world. The aim of the HTA Database is to improve the quality and cost-effectiveness of health care.

3 NHS Economic Evaluation Database (EED) This assists decision-makers by systematically identifying economic evaluations from around the world, appraising their quality, and highlighting their relative strengths and weaknesses. NHS EED is produced by the Centre for Reviews and Dissemination (CRD) at the University of York. To search DARE, HTA or EED individually, click on the More Resources button on the tool bar across the top of the Cochrane Library home page and click on the option for service you wish to search. Browsing the Cochrane Database of Systematic Reviews (CDSR) It is possible to browse the CDSR by health topic group or by Cochrane Review Group. Click on the Cochrane Reviews button on tool bar across the Cochrane Library home page and select Browse by Topic from the drop-down list. Browsing the CDSR by health topic group 1. Click on the broad health topic of interest, e.g. Heart & Circulation and then on a sub-heading related to your specific interest, e.g. Deep vein thrombosis and then a further sub-heading (if these are provided), e.g. Prevention: physical approaches, until you get to a list of review titles. You may need to click a show more link to display the full list of relevant sub-headings. 2. Click on the title to see the full record or review, e.g. Graduated compression stockings for prevention of deep vein thrombosis. The review will be displayed on the web page. For a PDF version of the review to save or print, click on the red PDF button in the left hand column and choose your preferred version of the review. The standard version is sufficiently detailed for most purposes.

4 Browsing by Cochrane Review Group 1. Click on the Cochrane Reviews button on the tool bar across the Cochrane Library home page and select Browse by Review Group from the drop-down list. 2. Click on the name of the review group of interest, e.g. Pregnancy and Childbirth Group and then on a sub-heading, e.g. Tobacco, drugs & alcohol. To view a full review, e.g. Psychosocial interventions for supporting women to stop smoking in pregnancy, click on its title. 3. The review will be displayed on the web page. For a PDF version of the review to save or print, click on the red PDF button in the left hand column and choose your preferred version of the review. The standard version is sufficiently detailed for most purposes.

5 Conducting a simple keyword search of the whole Cochrane Library 1. Click in the Search box at the top right of the Cochrane Library home page. Enter freetext terms (i.e. words that you think of) e.g. aspirin and angina and click on the Search button. The total number of results found and a breakdown by section of the Cochrane Library will be displayed. The Cochrane systematic reviews will be listed first. Browse through the results and click the title to see the full-text of a review or protocol 2. If your first search retrieves too many results, you could restrict it to words in the titles of records by selecting Record Title from the drop-down list to the left of the search box. Conducting an advanced search of the whole Cochrane Library 1. Click on the Advanced Search link under the simple search box on the Cochrane Library home page. 2. The Search Limits facility within Advanced Search allows you to limit a search to particular databases within the Cochrane Library, specify document status and a range of publication dates. 3. Under Advanced Search also is also an option to search the Cochrane Library by MeSH (Medical Subject Headings) via the Medical Terms (MeSH) tab. Many records in the Cochrane Library have been assigned Medical Subject Headings (MeSH terms). These are controlled index terms and can be a very effective aid in searching. If you find a record in the CDSR which matches your needs, click on the title link and then on the i button in the left hand

6 column. The details displayed include the Medical Subject Headings (MeSH) that have been assigned to the record. By searching with these same terms you can trace other material on the same topic. To perform a search on a MeSH term, click on it. To conduct a thorough search it is worth conducting two searches: one using MeSH terms and one using free-text terms. Viewing search results Search results from each section of the Cochrane Library are listed separately and in order of relevance. Cochrane Reviews are listed first. Click Other Reviews, Trials, etc. to see search results from the other databases within the library. Only the Cochrane Reviews are available in full-text. Entries in the other databases in the library provide either basic bibliographic details or structured abstracts. As you browse through the list of reviews, click on a title to view the full-text of a review. If you wish to print or save a copy of a review, click on one of the PDF options above the review s abstract and print or save this version of the file.

7 Search tips To search for a phrase, enter it in quotation marks, e.g. colon cancer. If you don t include the quotation marks, the system will search for colon AND cancer, which may retrieve many irrelevant results. The system searches for plurals automatically, e.g. a search for child will also find children. You can use the truncation/wildcard symbol *, e.g. depress* will find depression, depressive, depressed, etc. at either end of a word or in the middle, e.g. *depress* will include antidepressants in the search. The system searches for some alternative spellings automatically (e.g. tumor/tumour), but to be certain of catching alternatives, insert * as a wildcard at the appropriate point in the word, e.g. isch*mic to find ischaemic or ischemic. Include brackets in your search statement to control the order in which the search is executed, if you are using both AND and OR, e.g. magnesium AND (eclampsia OR perinatal asphyxia) You can use NEAR in a search statement instead of AND to narrow your search. e.g. smoking NEAR pregnancy will find the two words within 6 words of each other in either order, so is more specific than using AND. NEAR/n will find the words within n words of each other in either order, e.g. NEAR/4.

8 To search for a term that may be hyphenated, enter both alternatives, e.g. epstein barr or epstein-barr. Rob Caley Avril Robarts Library July 2017