Searching for studies

***The Cochrane PaPaS Group closes on 31 March 2023 and this website will be archived; please contact support@cochrane.org with any questions***

We hope that the information below is useful for authors when preparing a Cochrane protocol or review for PaPaS. We recommend that this is used as a guide, and suggest that details may vary depending on the topic area. Authors are advised to contact us for support on individual titles.

The information on this page was last updated in 2017.

Searching for studies

Electronic searches

A comprehensive, unbiased search is one of the key differences between a systematic review and a traditional review. While electronic databases such as MEDLINE are powerful tools for locating studies, only 30 to 80% of all known published randomised controlled trials (RCTs) are identifiable using MEDLINE (depending on the area or specific question).

To protect against bias and ensure that all relevant data are included in a review, it is important to use a variety of sources to identify studies that could be included. These sources must be reported in the protocol (and the completed review) so that readers know:

the databases and information sources that have been searched;
the years searched;
the search terms used.

Enough details should be given for others to replicate the search, so the search strategies used to search the various databases should be reproduced in the Appendices of the review.

The guidelines below indicate the detail and type of information that should be provided in the protocol.

The PaPaS review group maintains a "Register of Studies" of pain, palliative and supportive care trials. Currently, over 45,000 RCTs and clinical trials have been identified, and are being assessed for inclusion in the Register. The trials that have been assessed and meet the inclusion criteria are published in the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library. These trials can be identified by entering the search term: SR SYMPT in the searching dialogue box in the Cochrane Library.

In addition to providing the register of trials, the PaPaS Information Specialist can provide assistance to individual review authors to help them write their search strategy and running searches. Due to limited resources, however, we may sometimes ask that authors also use services available to them locally such as from a medical librarian or information officer within their host institution (Hospital, University, Research Unit, etc) if a large number of databases are to be searched.

Guidance for presenting searching information in Cochrane protocols

These notes were originally prepared by Sylvia Bickley (former PaPaS Information Specialist) and updated by Jo Abbott (current Information Specialist) to help review authors complete the section in RevMan called 'Search methods for identification of studies'. Review authors may copy and adapt these notes for their protocol.

Electronic searches

Electronic databases

To identify studies for inclusion in this review, detailed search strategies will be developed for each electronic database searched. These will be based on the search strategy developed for MEDLINE but revised appropriately for each database.

Review authors: If applicable, i.e., if the review will be confined to RCTs/CCTs, include the following sentence.

The search strategy will combine the subject search with the appropriate study design filter as described in section 6.4.11. of The Cochrane Handbook of Systematic Reviews of Interventions.

The subject search will use a combination of controlled vocabulary and free text terms based on the search strategy for searching MEDLINE which can be seen in Appendix 1.

(Review authors: state that you plan to search for studies irrespective of language).

The search will attempt to identify all relevant studies irrespective of language. Non-English papers will be assessed and, if necessary, translated, with the assistance of a native speaker.

Review authors: include here your search strategy for application to MEDLINE in Appendix 1, identifying the controlled vocabulary (MeSH) terms and free-text terms, in the format it will be applied to MEDLINE:

etc

Databases to be searched

Review authors: List the databases and years you plan to search. Please note that reviews should also report which platform was used to search any given database (e.g. OVID, EBSCO etc) because different platforms use different syntax.

NB. It is not necessary to search a database from its inception until the present day if the drug or treatment under review has become available only in, for example, the last ten years. The following is the order of listing required by Cochrane.

* The Cochrane Central Register of Controlled Trials (CENTRAL): The Cochrane Library (Issue ?, 201?)

* MEDLINE - OVID (e.g. 1966 to Oct week 3 2015)

(then other databases, for example:)

* Embase - OVID (dates)

* CINAHL - EBSCO (dates)

* PsycINFO -OVID (dates)

* LILACS - Birme (dates) ....etc.

Searching other resources

Trials registries

It is important to also search for ongoing trials. The following should be searched: clinicaltrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (who.int/trialsearch/). Others may also be searched in addition if wished.

Guides to trial registers

Finding clinical trials, research registers and research results, York Health Economics Consortium, University of York. This resource provides a listing of trials and research registers, and a quick reference guide to the search basics for each resource.

Handsearching

We no longer require authors to handsearch. However, the information here may be useful for those wishing to proceed.

Review authors: Identify the journals important to this review and the total period the handsearching should cover, indicating the years not already searched as part of the Cochrane PaPaS review group's handsearching programme. For example, 'The following journals will be handsearched for the period 19?? - 201?.'

Reference lists

Review authors: Reference lists of other reports, reviews, textbooks, etc, may be important sources of studies eligible for this review.

The reference lists of all eligible trials, key textbooks, and previous systematic reviews will be searched for additional studies.

Unpublished data

Review authors: State what steps you will take to identify unpublished studies, eg, searching conference proceedings and abstracts, writing to authors; manufacturers; drug companies etc. List those people you plan to contact).

Strategies

Pain search strategy

(Search strategy checked for updates June 2008)

The following search strategy for searching CENTRAL was devised by Sylvia Bickley in 2008 for the identification of pain studies.

MESH TERMS are in uppercase

#1 Exp PAIN

#2 Exp HEADACHE DISORDERS

#3 PAIN MEASUREMENT

#4 PAIN CLINICS

#5 Exp MYOFASCIAL PAIN SYNDROMES

#6 NOCICEPTORS

#7 Exp ANALGESIA

#8 Exp ANALGESICS

#9 HYPERALGESIA

#10 HYPERESTHESIA

#11 pain* in Record Title or pain* in Abstract

#12 analgesi*

#13 transcutaneous NEXT electric* NEXT nerve NEXT stimulation

#14 tens in Record Title OR tens in Abstract

#15 arthralgi* AND pain*

#16 arthriti* AND pain*

#17 headache* in Record Title OR headache* in Abstract OR migrain* in Record Title OR migrain* in Abstract OR cephalalgi* in Record Title OR cephalalgi* in Abstract OR hemicrani* in Record Title OR hemicrani* in Abstract

#18 neuralgi*

#19 glossalgi*

#20 toothache* or tooth-ache* or odontalgi* or earache* or ear-ache* or colic*

#21 nociceptor*

#22 audioanalgesi* or audio-analgesi*

#23 ((acupuncture or electroacupuncture or electro-acupuncture) and pain*)

#24 hyperalgisi* or hyperesthesi*

#25 ((epidural next anesthe*) or (epidural next anaesthe*) and pain*)

#26 DYSMENORRHEA

#27 (dysmenorrhea or dysmenorrhoea)

#28 metatarsalgi*

#29 HYPERESTHESIA

#30 ((fibromyalgi* or fibrositis) and pain*)

#31 (#1 or #2 or #3 or #4 or #5 or #6 or #7 or #8 or #9 or #10 or #11 or #12 or #13 or #14 or #15 or #16 or #17 or #18 or #19 or #20 or #21 or #22 or #23 or #24 or #25 or #26 or #27 or #28 or #29 or #29 or #30)

Palliative care search strategy

(Search strategy checked for updates June 2008):

The following search strategy for searching CENTRAL was devised by Sylvia Bickley for the identification of palliative care studies.

MESH TERMS are in uppercase

#1 PALLIATIVE CARE

#2 Exp TERMINAL-CARE

#3 TERMINALLY-ILL

#4 ATTITUDE-TO-DEATH

#5 Exp BEREAVEMENT

#6 RIGHT-TO-DIE

#7 HOSPICES

#8 RESPITE-CARE

#9 palliat*

#10 terminal* NEAR/6 care*

#11 terminal* NEAR/6 caring

#12 terminal* NEAR/6 ill*

#13 hospice*

#14 bereav*

#15 grief in Record Title OR grief in Abstract OR griev* in Record Title ORgriev* in Abstract

#16 euthanas*

#17 attitude* NEAR/6 death*

#18 assist* NEAR/6 death*

#19 assist* NEAR/6 die*

#20 assist* NEAR/6 suicide*)

#21 help* NEAR/6 death*

#22 help* NEAR/6 die*

#23 help* NEAR/6 suicide*

#24 aid* NEAR/6 death*

#25 aid* NEAR/6 die*

#26 aid* NEAR/6 suicide*

#27 right* NEAR/6 die*

#28 respite NEAR/6 care*

#29 respite NEAR/6 caring

#30 living NEXT will*

#31 advance* NEXT directive*

#32 advance* NEXT care NEXT plan

#33 ?end of life? NEAR/6 care

#34 ?end of life? NEAR/6 caring

#35 #1 OR #2 OR #3 OR #4 OR #5 OR #6 OR #7 OR #8 OR #9 OR #10 OR

#11 OR #12 OR #13 OR #14 OR #15 OR #16 OR #17 OR #18 OR #19

OR #20 OR #21 OR #22 OR #23 OR #24 OR #25 OR #26 OR #27 OR #28 Or#29 OR #30 OR #31 OR #32 OR #33 OR #34

#36 ((chemoth* AND (induced NEAR/6 vomiting)) OR (chemoth* AND (induced

NEXT sickness)))

#37 ((chemoth* AND (related NEAR/6 sickness)) OR (chemoth* AND (related

NEAR/6 vomiting)))

#38 ((induced NEXT hypersalivation) OR (induced NEXT hyposalivation))

#39 induced NEXT xerostomi*

#40 ((induced NEAR/6 cachexi*) OR (related NEAR/6 cachexi*))

#41 (?terminal* ill*? AND ?symptom* management?)

#42 ((anorexi* NEAR/6 cancer*) OR (anorexi* NEAR/6 carcinoma*))

#43 anorexi* NEAR/6 radiotherap*

#44 anorexi* NEAR/6 radio-chemotherap*

#45 ((cancer NEAR/6 weight-loss) OR (cancer NEAR/6 weight NEXT loss) OR

(cancer NEAR/6 weight NEXT losing) OR (carcinoma* NEAR/6 weight-loss) OR (carcinoma* NEAR/6 weight NEXT loss) OR (carcinoma* NEAR/6 weight NEXT losing))

#46 (( cancer NEAR/6 weight-gain*) OR (cancer NEAR/6 weight NEXT gain*) OR

(carcinoma* NEAR/6 weight-gain) OR (carcinoma* NEAR/6 weight NEXT gain*))

#47 ((cancer NEAR/6 appetite NEXT stimulat*) OR (carcinoma* NEAR/6 appetite

NEXT stimulat*))

#48 appetite NEXT stimulat*

#49 ((cancer NEAR/6 hot NEXT flush*) OR (cancer NEAR/6 hot NEXT flash*))

#50 related NEXT cachexi*

#51 neoplastic NEXT cachexi*

#52 ((induced NEAR/6 constipat*) OR (induced NEAR/6 emesis)

#53 opioid NEXT induced

#54 morphine NEXT induced

#55 methadone NEXT induced

#56 cancer or carcinoma* AND music NEXT therapy

#57 ((cancer or carcinoma*) AND ((aroma NEXT therapy) OR aromatherapy))

#58 dysphag* NEAR/6 cancer

#59 (symptom NEXT control AND (cancer OR carcinoma*))

#60 radiotherap* NEAR/6 induced

#61 chemotherap* NEAR/6 induced

#62 radiotherap* NEXT related

#63 chemotherap* NEXT related

#64 ((cancer NEXT related) OR (carcinoma* NEXT related))

#65 #36 or #37 OR #38 OR #39 OR #40 OR #41 OR #42 OR #43 OR#44 OR #45 OR #46 OR #47 OR #48 OR #49 OR #50 OR #51 OR #52 OR #53 OR#54 OR #55 OR #56 OR #57 OR #58 OR #59 OR #60 OR #61 OR #62 OR #63OR #64

#66 #35 OR #65

Trials on supportive care

No definitive search strategy has been finalised for trials on supportive care. On-going searches are carried out to identify trials in supportive care using phrase searching and specific search strategies for reviews these are included in the Group's Trials Register. Currently around 900 records are related to supportive care.