Database guide last
updated October 10, 2012

Copyright 2009,
Wolters Kluwer Health

The Cochrane Methodology Register is a database of studies relevant to the methods of systematic reviews of healthcare and social interventions.

The database includes journal articles, book chapters, conference proceedings, conference abstracts and reports of ongoing methodological research. Relevant records are identified primarily through a program of hand searching undertaken by the UK Cochrane Centre. The register aims to include all published reports of empirical methodological studies that could be relevant for inclusion in a Cochrane methodology review, along with comparative and descriptive studies relevant to the conduct of systematic reviews of healthcare interventions.

The Cochrane Methodology Register contains over 9,000 bibliographic references to controlled trials in health care. The content of the Cochrane Methodology Register is being constantly expanded upon as a direct result of an extensive hand searching program and the development of a series of search strategies in MEDLINE and EMBASE to identify relevant reports. This activity is funded by the National Health Service Research and Development Methodology Programme in England.

The limit of databases that you can select for a multifile search session is based upon database segments rather than actual databases. The Ovid multifile segment limit is set at 120 to avoid impacting your search sessions. This database includes 1 segment.

This database is updated online quarterly.

Quotation marks can be used to retrieve records that contain literal strings, when the string includes special characters, such as a forward slash (/).

Quotation marks can also be used to retrieve records that contain numbers that may otherwise be confused for earlier searches. In the example, a search for 3.vo would limit the string from your third search in your search history to the volume field. By including the number in quotation marks, the search will retrieve documents with a 3 in the volume number.

If you are searching for a multi-file of ebmz you can put in any or all the segments that make up ebmz. For example, command “dog.ti use coch,acp,dare,cca,cctr,clcmr,clhta,cleed" to include any or all segments of ebmz.

Therefore a search: at risk for diabetes.ti will also find: at risk of diabetes. The distance of one word in between is kept, but the stopword "for" is ignored.

A limit to Abstracts restricts retrieval to documents that include an abstract.

A limit to New Reviews restricts retrieval to documents which have been added to the database since the last update.

A limit to Review Articles restricts retrieval to articles which are reviews of a subject.

A limit by Publication Type restricts retrieval by publication types including classifications such as:

A limit by Publication Year restricts retrieval to the selected year(s).

If you choose this option you will be prompted to enter the desired year; the format is 4 digits: "1989" or a range: "1994-1995".

Currently no tools are available for this database.

Accession Number
  CMR-9993
Authors
  Shrier I. Steele R. Platt R.
Title
  A novel approach to mixed-treatment meta-analyses [abstract]
Source
  XIV Cochrane Colloquium. 55p. 2006 October 23-26, Dublin, Ireland.
Abstract
  Background: Traditional meta-analyses only include direct head-to-head studies.
  However, it may be unethical to compare a novel treatment to placebo if an
  effective treatment exists. A meta-analysis restricted to direct comparisons
  would require many years to evaluate a novel treatment in the context of overall
  patient care. Mixed-treatment meta-analysis (MTM) overcomes these limitations by
  including indirect evidence, i.e. compare treatment A to treatment B when there
  are studies comparing each to placebo. Current methods for MTM use only the
  variance data to combine studies and ignore other inter-study differences that
  might affect the effect estimate, except in an adhoc analysis. Objectives: To
  describe an approach to mixed-treatment meta-analysis that allows the
  incorporation of study characteristics that potentially modify the estimate of
  the effect. Methods: Any meta-analysis is simply an observational study where
  each study represents an individual subject, and MTM can be viewed as a missing
  data problem. For example, study A has the 'subject' characteristics: year 1995,
  35% female, OR (A vs Ref) = 2.1 (95%CI = 1.2, 3.9), and a 20% reference group 
  mortality. Study B's characteristics are: year 1998, 30% female, OR (B vs Ref)
  = 0.9 (95%CI = 0.5, 1.6), and a 30% reference group mortality. Comparing these
  two studies, study A has missing data for the variable "B vs Ref" and study B
  has missing data for the variable "A vs Ref". We use all the available data and
  the multiple imputation method to obtain estimates for the missing values. We use
  data on migraine treatments to compare the results from traditional MTM to our
  approach. Results: The data comparing the incoherence observed between the
  estimate of effect from the two approaches are currently being analysed and will
  be presented. Conclusions: A novel approach for MTM is described. Validation of
  the approach is in progress.
Correspondence Address
  Centre for Clinical Epidemiology and Community Studies, SMBD-Jewish General Hospital,
  McGill University, Montreal, Canada. [email protected]
Publication Type
  Journal article
Keywords
  CMR: Review methodology - meta-analysis - multiple comparisons; CMRA2.1.
Year of Publication
  2006

Accession Number
  CMR-9999
Authors
  Vandermeer B. Bialy L. Johnston B. Hooton N. Hartling L. Klassen T. Wiebe N.
Title
  Meta-analyses of safety data: a comparison of exact versus asymptotic methods
  [abstract]
Source
  XIV Cochrane Colloquium. 53p. 2006 October 23-26, Dublin, Ireland.
Abstract
  Background: More so than efficacy events, safety events can be quite rare.
  Asymptotic approximations are known to be imprecise or even invalid in the
  presence of rare events. Nevertheless, the great majority of systematic reviews
  continue to use normal approximations regardless of the distribution of the data.
  Objectives: Establish and describe a sample of Cochrane and non-Cochrane
  meta-analyses of safety data. Determine which factors (i.e. event rates, number
  of studies etc.) are most important in addressing when exact methods are
  preferable to asymptotic methods. Methods: A large sample of Cochrane (n=500)
  and non-Cochrane (n=200) systematic reviews was randomly selected and a database
  of safety meta-analyses established. Point estimates and confidence intervals
  for each meta-analysis were recalculated using exact methods and compared to
  the results of the asymptotic methods used in the systematic review. Results:
  Cochrane reviews were nearly four times as likely as non-Cochrane reviews to
  contain meta-analyses of safety data (35% compared to 9%). More than 50% of safety
  meta-analyses contained an outcome with a rare event rate (< 5%). For rare event
  metaanalyses, exact point estimates differed substantially from asymptotic
  estimates 38% of the time, compared to 17% for those without rare events. Exact
  confidence intervals differed substantially from asymptotic ones 67% of the time
  compared to only 19% for those without rare events. The magnitude of differences
  was also correlated with the number of studies and the summary statistic used to
  combine the data. Conclusions: Asymptotic methods will not always be a good
  approximation for exact methods in safety meta-analyses. Event rates and the number
  of studies should be closely examined when choosing the statistical method for
  combining rare event data. This project was funded by a grant from the Canadian
  Co-ordinating Office for Health Technology Assessments (CCOHTA) now called
  Canadian Agency for Drugs and Technologies in Health (CADTH).
Correspondence Address
  Department of Pediatrics, University of Alberta, Edmonton, Canada. [email protected]
Publication Type
  Journal article
Keywords
  CMR: Review methodology - presentation of reviews - adverse effects; CMRA2.
Year of Publication
  2006

The Cochrane Collaboration
Home Page: http://www.cochrane.org

The materials contained herein are proprietary to the publishers and/or individual copyright holders and may only be used by authorized users of the subscribing institutions for internal or personal research. Authorized users may

1. print data obtained from searches and make limited copies of such printed search results,
2. download data obtained from searches and
3. retransmit search results electronically or otherwise to a limited number of authorized users at the same institution.

Authorized users are precluded from:

1. copying, duplication, redistribution, retransmission, publication, transfer or commercial or other exploitation of the databases or the contents thereof, except as permitted herein or pursuant to user guidelines of the individual copyright holders,
2. preparation of derivative works or incorporation of the databases or contents thereof in any other work or system;
3. downloading of the contents in their entirety or lengthy sequence.

Authorized users are referred to the individual copyright holder and/or to the copyright holder's usage guidelines within this database for additional restrictions which may be imposed by the copyright holder.