Happy new year to all Cochrane TSCs! In this month's digest, we're going to talk forums, look at the pros and cons of limiting searches by entry dates for updates and follow up on discussions at the Colloquium in Vienna on searching regulatory databases. There's also an important point for you to note on reporting corrections to CENTRAL records, and editing records for publication in CENTRAL and CRSO.
TSC and CRS Forums
Use of the TSC and CRS discussion forums
A reminder that the TSC and CRS discussion forums still exist, and you can access them through the TSC Portal.
These forums have been quiet of late, but we think they still may provide some advantages over the email list. Forums create a discussion environment by saving information posted on a certain topic for people to go back to at any time. They allow all of us to see what is being posted and the responses generated. The content is also searchable, so we can find answers to questions that have been asked before more easily than we can through emails. We think they are probably best suited to topics where there is a discussion, rather than things like requests for papers or news items, which should still come through the TSC email list.
Be aware that the first line of your forum post will also appear in any emails generated, so make sure you mention the topic early in your post to get it noticed!
You can subscribe to the forums by email, so that when a new topic is posted you get an email to alert you. Do this by visiting the forum, clicking on a topic and clicking on the link at the bottom "Subscribe to posts tagged with Trials Search Co-ordinators" (for TSC Forum) or the link "Subscribe to posts tagged with Cochrane Register of Studies (CRS)" (for CRS Forum). This will then take you into a screen where you can choose "Mail" from a drop down menu and then click "Subscribe".
Chris Mavergames has put together a video tutorial on using Forums, access it here.
Entry dates
Searching MEDLINE and Ovid Embase for review updates
Limiting by date for update searches can be difficult. Limiting by publication date should be avoided in all databases as this runs the risk of missing older journal articles which have been added to a database since the last searches were run.
Limiting by entry week.em in Embase) can become complicated because in Embase this date changes. with each global reload (see the Embase Ovid Guide for information).You might want to consider using the "Date Delivered" (DD) field in Embase as an alternative to the .em entry week field, this also allows you to add a date range to your search. The date delivered field is the date the record was issued on Embase by Elsevier. To do this, add to the end of your search:
limit [line number] to dd=yyyymmdd-yyyymmdd
If you want to let us know how using the DD field works out for you, drop us an email or share your experiences on the TSC Forum.
In the case of Ovid MEDLINE, the Entry Date (ED) field contains the date (year, month and day) on which indexing for a record was completed and it was added to MEDLINE by NLM. Terms in this field appear in the format YYYYMMDD (For example: Sept 29, 2004 appears as 20040929.ed). However, not all the records have an entry date in Ovid's In-Process & Other Non-Indexed Citations MEDLINE database, so if you do use entry date limits in Ovid MEDLINE it is recommended that you search the In-Process & Other Non-Indexed Citations file separately (see section 6.4.12 of the Handbook).
PubMed also allows you to limit a search by the date the record was created on PubMed, using the "Create Date" [CDRT] field. Find more details here.
An alternative way of updating the search is to do the whole search again and then deduplicate it against the previous search(es), either manually in reference management software or using the deduplicating functionality in the CRS.
Searching regulatory databases
Searching Regulatory Databases (European Medicines Agency (EMA) and US Food and Drugs Administration (FDA)) for Cochrane Reviews
In a recent editorial on the Cochrane Library, Jeppe Schroll and Lisa Bero suggested “that searching regulatory data from the EMA and the FDA should be part of any Cochrane Review of drug interventions”. This recommendation was based on research showing “that including unpublished data from regulatory agencies changed the results of the original meta-analysis”.
This provoked some discussion in Vienna, so we wanted to highlight the implications of this for TSCs.
When should TSCs consider searching these sources for Cochrane reviews? Don’t panic! Searching regulatory databases should only be considered if all the following circumstances apply:
If the drug/device is newly approved by EMA or FDA (last 5 years) or is utilised for a new indication (last 5 years)
If the drug/device has been approved for use for the condition in question
When the drug/device is compared to placebo for the comparisons in the review; although searches for reviews of other drug comparisons might also yield results
Searching the databases under the above conditions could provide useful study level data on drug efficacy. These sources are difficult to search and the search interfaces change regularly. The data can be difficult to analyse, therefore TSCs should discuss with their author teams whether the above circumstances apply to the review question, and whether to search these sources.
Do you have any experience searching these sources or any tips you can share? If so, we would love to hear from you (tsc-support@cochrane.org).
A fuller version of this document is available on the TSC Portal (Archie login required), under the heading "Handbooks, policy manual, standards and style guide".
Further reading:
[1] Jeppe Schroll, Lisa Bero. Regulatory agencies hold the key to improving Cochrane Reviews of drugs[editorial]. Cochrane Database of Systematic Reviews 2015;(4): 10.1002/14651858.ED000098
[2] Hart B, Lundh A, Bero L. Effect of reporting bias on meta-analyses of drug trials: reanalysis of meta-analyses. BMJ 2012;344:d7202. dx.doi.org/10.1136/bmj.d7202
[3] Chan AW. Out of sight but not out of mind: how to search for unpublished clinical trial evidence. BMJ. 2012 Jan 3;344:d8013. doi: 10.1136/bmj.d8013.http://www.ncbi.nlm.nih.gov/pubmed/22214892
Reporting errors via CRSO and editing records for CENTRAL and CRSO
Changes to CRS / CENTRAL records
We had a query this week from a TSC about reporting duplicates on CENTRAL via the CENTRAL Corrections tab on CRS Online (CRSO) (Archie login required). She had noticed that the corrections that she had submitted had not been processed.
We asked Gordon for some clarification. Corrections to CENTRAL records are handled in CRSO by suggesting alternative field values, requesting that a CENTRAL record be removed, or reporting that the record is a duplicate of another CENTRAL record. Currently all those requests are being stored but not acted upon. This is partly because under the current publishing model with Wiley no records are deleted from CENTRAL, even if they have been marked for deletion in a TSC's register, and partly because analysis of the proposed changes show that some requested changes are not in line with HarmoniSR guidelines. The current plan is to process the deletion requests before the next Wiley full reload of CENTRAL (no date is yet confirmed), and to process the change requests once the HarmoniSR processing is fully implemented with CRS Web so it is important to continue submitting requests.
Another thing to bear in mind is that as part of our agreement with PubMed and Elsevier we are not able to make changes to records that we have harvested from them. Many of the records on CENTRAL and CRSO come from the Embase Project and from a feed from PubMed. TSCs should be aware that if they make any edits to these records in their CRS segment, the changes will not appear on CENTRAL or CRSO. The changes will be retained in the Group's CRS segment but will not be published elsewhere.
Contact us...
Don't forget, previous editions of the TSC Support Team digest are available on the TSC Portal (Archie login required)
Contact the TSC Support Team for help with any TSC related issue (including CRS technical support): tsc-support@cochrane.org
The TSC Support Team:
Liz Doney I Sam Faulkner I Ruth Foxlee
Anne Littlewood I Doug Salzwedel