Authors: Wichor M Bramer, Gerdien B de Jonge, Melissa L Rethlefsen...

Creating search strategies for systematic reviews, finding the best balance between sensitivity and specificity, and translating search strategies between databases is challenging. Several methods describe standards for systematic search strategies, but a consistent approach for creating an exhaustive search strategy has not yet been fully described in enough detail to be fully replicable. The authors have established a method that describes step by step the process of developing a systematic search strategy as needed in the systematic review. This method describes how single-line search strategies can be prepared in a text document by typing search syntax (such as field codes, parentheses, and Boolean operators) before copying and pasting search terms (keywords and free-text synonyms) that are found in the thesaurus. To help ensure term completeness, we developed a novel optimization technique that is mainly based on comparing the results retrieved by thesaurus terms with those retrieved by the free-text search words to identify potentially relevant candidate search terms. Macros in Microsoft Word have been developed to convert syntaxes between databases and interfaces almost automatically. This method helps information specialists in developing librarian-mediated searches for systematic reviews as well as medical and health care practitioners who are searching for evidence to answer clinical questions. The described method can be used to create complex and comprehensive search strategies for different databases and interfaces, such as those that are needed when searching for relevant references for systematic reviews, and will assist both information specialists and practitioners when they are searching the biomedical literature.

Topics: Abstracting and Indexing; Databases, Factual; Humans; Information Storage and Retrieval; Medical Subject Headings; Review Literature as Topic; Vocabulary, Controlled

PubMed: 30271302
DOI: 10.5195/jmla.2018.283

Comparative Study

Authors: Abigail M Methley, Stephen Campbell, Carolyn Chew-Graham...

BACKGROUND

Qualitative systematic reviews are increasing in popularity in evidence based health care. Difficulties have been reported in conducting literature searches of qualitative research using the PICO search tool. An alternative search tool, entitled SPIDER, was recently developed for more effective searching of qualitative research, but remained untested beyond its development team.

METHODS

In this article we tested the 'SPIDER' search tool in a systematic narrative review of qualitative literature investigating the health care experiences of people with Multiple Sclerosis. Identical search terms were combined into the PICO or SPIDER search tool and compared across Ovid MEDLINE, Ovid EMBASE and EBSCO CINAHL Plus databases. In addition, we added to this method by comparing initial SPIDER and PICO tools to a modified version of PICO with added qualitative search terms (PICOS).

RESULTS

Results showed a greater number of hits from the PICO searches, in comparison to the SPIDER searches, with greater sensitivity. SPIDER searches showed greatest specificity for every database. The modified PICO demonstrated equal or higher sensitivity than SPIDER searches, and equal or lower specificity than SPIDER searches. The modified PICO demonstrated lower sensitivity and greater specificity than PICO searches.

CONCLUSIONS

The recommendations for practice are therefore to use the PICO tool for a fully comprehensive search but the PICOS tool where time and resources are limited. Based on these limited findings the SPIDER tool would not be recommended due to the risk of not identifying relevant papers, but has potential due to its greater specificity.

Topics: Animals; Databases, Bibliographic; Humans; Information Storage and Retrieval; Meta-Analysis as Topic; Multiple Sclerosis; Qualitative Research; Review Literature as Topic; Search Engine; Sensitivity and Specificity

PubMed: 25413154
DOI: 10.1186/s12913-014-0579-0

Authors: Mette Brandt Eriksen, Tove Faber Frandsen

OBJECTIVE

This review aimed to determine if the use of the patient, intervention, comparison, outcome (PICO) model as a search strategy tool affects the quality of a literature search.

METHODS

A comprehensive literature search was conducted in PubMed, Embase, CINAHL, PsycINFO, Cochrane Library, Web of Science, Library and Information Science Abstracts (LISA), Scopus, and the National Library of Medicine (NLM) catalog up until January 9, 2017. Reference lists were scrutinized, and citation searches were performed on the included studies. The primary outcome was the quality of literature searches and the secondary outcome was time spent on the literature search when the PICO model was used as a search strategy tool, compared to the use of another conceptualizing tool or unguided searching.

RESULTS

A total of 2,163 records were identified, and after removal of duplicates and initial screening, 22 full-text articles were assessed. Of these, 19 studies were excluded and 3 studies were included, data were extracted, risk of bias was assessed, and a qualitative analysis was conducted. The included studies compared PICO to the PIC truncation or links to related articles in PubMed, PICOS, and sample, phenomenon of interest, design, evaluation, research type (SPIDER). One study compared PICO to unguided searching. Due to differences in intervention, no quantitative analysis was performed.

CONCLUSIONS

Only few studies exist that assess the effect of the PICO model vis-a-vis other available models or even vis-a-vis the use of no model. Before implications for current practice can be drawn, well-designed studies are needed to evaluate the role of the tool used to devise a search strategy.

Topics: Evidence-Based Medicine; Humans; Information Storage and Retrieval; Periodicals as Topic; Quality Assurance, Health Care; United States

PubMed: 30271283
DOI: 10.5195/jmla.2018.345

Review

Authors: Wichor M Bramer, Melissa L Rethlefsen, Jos Kleijnen...

BACKGROUND

Within systematic reviews, when searching for relevant references, it is advisable to use multiple databases. However, searching databases is laborious and time-consuming, as syntax of search strategies are database specific. We aimed to determine the optimal combination of databases needed to conduct efficient searches in systematic reviews and whether the current practice in published reviews is appropriate. While previous studies determined the coverage of databases, we analyzed the actual retrieval from the original searches for systematic reviews.

METHODS

Since May 2013, the first author prospectively recorded results from systematic review searches that he performed at his institution. PubMed was used to identify systematic reviews published using our search strategy results. For each published systematic review, we extracted the references of the included studies. Using the prospectively recorded results and the studies included in the publications, we calculated recall, precision, and number needed to read for single databases and databases in combination. We assessed the frequency at which databases and combinations would achieve varying levels of recall (i.e., 95%). For a sample of 200 recently published systematic reviews, we calculated how many had used enough databases to ensure 95% recall.

RESULTS

A total of 58 published systematic reviews were included, totaling 1746 relevant references identified by our database searches, while 84 included references had been retrieved by other search methods. Sixteen percent of the included references (291 articles) were only found in a single database; Embase produced the most unique references (n = 132). The combination of Embase, MEDLINE, Web of Science Core Collection, and Google Scholar performed best, achieving an overall recall of 98.3 and 100% recall in 72% of systematic reviews. We estimate that 60% of published systematic reviews do not retrieve 95% of all available relevant references as many fail to search important databases. Other specialized databases, such as CINAHL or PsycINFO, add unique references to some reviews where the topic of the review is related to the focus of the database.

CONCLUSIONS

Optimal searches in systematic reviews should search at least Embase, MEDLINE, Web of Science, and Google Scholar as a minimum requirement to guarantee adequate and efficient coverage.

Topics: Databases, Bibliographic; Humans; Information Storage and Retrieval; Prospective Studies; Review Literature as Topic

PubMed: 29208034
DOI: 10.1186/s13643-017-0644-y

Authors: Andrew Booth, Simon Briscoe, Judy M Wright...

The requirement for literature searches that identify studies for inclusion in systematic reviews should be systematic, explicit, and reproducible extends, at least by implication, to other types of literature review. However, realist reviews commonly require literature searches that challenge systematic reporting; searches are iterative and involve multiple search strategies and approaches. Notwithstanding these challenges, reporting of the "realist search" can be structured to be transparent and to facilitate identification of innovative retrieval practices. Our six-component search framework consolidates and extends the structure advanced by Pawson, one of the originators of realist review: formulating the question, conducting the background search, searching for program theory, searching for empirical studies, searching to refine program theory and identifying relevant mid-range theory, and documenting and reporting the search process. This study reviews reports of search methods in 34 realist reviews published within the calendar year of 2016. Data from all eligible reviews were extracted from the search framework. Realist search reports poorly differentiate between the different search components. Review teams often conduct a single "big bang" multipurpose search to fulfill multiple functions within the review. However, it is acknowledged that realist searches are likely to be iterative and responsive to emergent data. Overall, the search for empirical studies appears most comprehensive in conduct and reporting detail. In contrast, searches to identify and refine program theory are poorly conducted, if at all, and poorly reported. Use of this framework offers greater transparency in conduct and reporting while preserving flexibility and methodological innovation.

Topics: Clinical Trials as Topic; Data Collection; Databases, Bibliographic; Empirical Research; Humans; Information Storage and Retrieval; Models, Theoretical; Publications; Research Design; Review Literature as Topic

PubMed: 31714016
DOI: 10.1002/jrsm.1386

Authors: William Schaut, Akash Shrivastav, Srikanth Ramakrishnan...

BACKGROUND

Manually keeping up-to-date with regulations such as directives, guidance, laws, and ordinances related to cell and gene therapy is a labor-intensive process. We used machine learning (ML) algorithms to create an augmented intelligent system to optimize systematic screening of global regulations to improve efficiency and reduce overall labor and missed regulations.

METHODS

Combining Boolean logic and artificial intelligence (i.e., augmented intelligence) for the search process, ML algorithms were used to identify and suggest relevant cell and gene therapy regulations. Suggested regulations were delivered to a landing page for further subject matter expert (SME) tagging of words/phrases to provide system relevance on functional words. Ongoing learning from the repository regulations continued to increase system reliability and performance. The automated ability to train and retrain the system allows for continued refinement and improvement of system accuracy. Automated daily searches for applicable regulations in global databases provide ongoing opportunities to update the repository.

RESULTS

Compared to manual searching, which required 3-4 SMEs to review ~115 regulations, the current system performance, with continuous system learning, requires 1 full-time equivalent to process approximately 9,000 regulations/day. Currently, system performance has 86% overall accuracy, a recommend recall of 87%, and a reject recall of 84%. A conservative search strategy is intentionally used to permit SMEs to assess low-recommended regulations in order to prevent missing any applicable regulations.

CONCLUSION

Compared to manual searches, our custom automated search system greatly improves the management of cell and gene therapy regulations and is efficient, cost effective, and accurate.

PubMed: 36950510
DOI: 10.3389/fmed.2023.1072767

Review

Authors: Madhur G Aggithaya, Saravu R Narahari

INTRODUCTION

The journals that publish on Ayurveda are increasingly indexed by popular medical databases in recent years. However, many Eastern journals are not indexed biomedical journal databases such as PubMed. Literature searches for Ayurveda continue to be challenging due to the nonavailability of active, unbiased dedicated databases for Ayurvedic literature. In 2010, authors identified 46 databases that can be used for systematic search of Ayurvedic papers and theses. This update reviewed our previous recommendation and identified current and relevant databases.

AIMS

To update on Ayurveda literature search and strategy to retrieve maximum publications.

METHODS

Author used psoriasis as an example to search previously listed databases and identify new. The population, intervention, control, and outcome table included keywords related to psoriasis and Ayurvedic terminologies for skin diseases. Current citation update status, search results, and search options of previous databases were assessed. Eight search strategies were developed. Hundred and five journals, both biomedical and Ayurveda, which publish on Ayurveda, were identified. Variability in databases was explored to identify bias in journal citation.

RESULTS

Five among 46 databases are now relevant - AYUSH research portal, Annotated Bibliography of Indian Medicine, Digital Helpline for Ayurveda Research Articles (DHARA), PubMed, and Directory of Open Access Journals. Search options in these databases are not uniform, and only PubMed allows complex search strategy. "The Researches in Ayurveda" and "Ayurvedic Research Database" (ARD) are important grey resources for hand searching. About 44/105 (41.5%) journals publishing Ayurvedic studies are not indexed in any database. Only 11/105 (10.4%) exclusive Ayurveda journals are indexed in PubMed.

CONCLUSION

AYUSH research portal and DHARA are two major portals after 2010. It is mandatory to search PubMed and four other databases because all five carry citations from different groups of journals. The hand searching is important to identify Ayurveda publications that are not indexed elsewhere. Availability information of citations in Ayurveda libraries from National Union Catalogue of Scientific Serials in India if regularly updated will improve the efficacy of hand searching. A grey database (ARD) contains unpublished PG/Ph.D. theses. The AYUSH portal, DHARA (funded by Ministry of AYUSH), and ARD should be merged to form single larger database to limit Ayurveda literature searches.

PubMed: 27313409
DOI: 10.4103/0974-8520.182754

Authors: Saqib H Ansari, Zohra S Lassi, Salima M Khowaja...

BACKGROUND

Hydroxyurea (hydroxycarbamide) promotes the production of foetal haemoglobin (HbF) by reactivating gamma-genes. Evidence has shown clinical benefits of hydroxyurea in people with sickle cell anemia; however, only a few studies have assessed this treatment in people with beta (β)-thalassaemia.

OBJECTIVES

The primary objective is to review the efficacy of hydroxyurea in reducing or ameliorating the requirement of blood transfusions in people with transfusion-dependent β-thalassaemia. The second objective is to review the safety of hydroxyurea with regards to severe adverse effects in this population.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register, compiled from electronic database searches and hand searching of journals and conference abstract books. We also searched electronic databases and trial registries, including ClinicalTrials.gov, the WHO ICTRP and PubMed (09 October 2018).Date of last search of the Group's haemoglobinopathies trials register: 04 March 2019.

SELECTION CRITERIA

Randomised controlled trials of hydroxyurea in people with transfusion-dependent β-thalassaemia, compared with placebo or standard treatment or comparing different doses of hydroxyurea.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion in the review, which was verified by a third author.

MAIN RESULTS

No trials were eligible for inclusion in this review.

AUTHORS' CONCLUSIONS

Currently, there is no high-quality evidence to support or challenge the continued use of hydroxyurea for managing people with transfusion-dependent β-thalassaemia. Multicentre, randomised controlled trials (compared to placebo or other available treatment, i.e. blood transfusion and iron chelation) are needed in order to assess the efficacy and safety of hydroxyurea for reducing the need for blood transfusion, for maintaining or improving mean haemoglobin levels, as well as for determining its cost-effectiveness.

Topics: Blood Transfusion; Hematinics; Humans; Hydroxyurea; beta-Thalassemia

PubMed: 30882896
DOI: 10.1002/14651858.CD012064.pub2

Review

Authors: Sarah R Hatt, Lawrence Gnanaraj

BACKGROUND

The clinical management of intermittent exotropia has been discussed extensively in the literature, yet there remains a lack of clarity regarding indications for intervention, the most effective form of treatment and whether or not there is an optimal time in the evolution of the disease at which any treatment should be carried out.

OBJECTIVES

The objective of this review was to analyse the effects of various surgical and non-surgical treatments in randomised trials of participants with intermittent exotropia, and to report intervention criteria and determine the significance of factors such as age with respect to outcome.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library, Issue 4, 2012), MEDLINE (January 1966 to May 2012), EMBASE (January 1980 to May 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to May 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 4 May 2012. We are no longer searching the UK Clinical Trials Gateway (UKCTG) for this review. We manually searched the British Orthoptic Journal up to 2002, and the proceedings of the European Strabismological Association (ESA), International Strabismological Association (ISA) and American Academy of Paediatric Ophthalmology and Strabismus meeting (AAPOS) up to 2001. We contacted researchers who are active in the field for information about further published or unpublished studies.

SELECTION CRITERIA

We included randomised controlled trials of any surgical or non-surgical treatment for intermittent exotropia.

DATA COLLECTION AND ANALYSIS

Each review author independently assessed study abstracts identified from the electronic and manual searches. Author analysis was then compared and full papers for appropriate studies were obtained.

MAIN RESULTS

We found one randomised trial that was eligible for inclusion. This trial showed that unilateral surgery was more effective than bilateral surgery for correcting the basic type of intermittent exotropia.

AUTHORS' CONCLUSIONS

The available literature consists mainly of retrospective case reviews, which are difficult to reliably interpret and analyse. The one randomised trial included found unilateral surgery more effective than bilateral surgery for basic intermittent exotropia. However, across all identified studies, measures of severity and thus criteria for intervention are poorly validated, and there appear to be no reliable natural history data. There is therefore a pressing need for improved measures of severity, a better understanding of the natural history and carefully planned clinical trials of treatment to improve the evidence base for the management of this condition.

Topics: Exotropia; Humans; Randomized Controlled Trials as Topic

PubMed: 23728647
DOI: 10.1002/14651858.CD003737.pub3

Review

Authors: Joseph G L Lee, Thomas Ylioja, Mellanye Lackey...

Research on the health of lesbian, gay, bisexual, and transgender (LGBT) populations can provide important information to address existing health inequalities. Finding existing research in LGBT health can prove challenging due to the plethora of terminology used. We sought to describe existing search strategies and to identify more comprehensive LGBT search terminology. We iteratively created a search string to identify systematic reviews and meta-analyses about LGBT health and implemented it in Embase, PubMed/MEDLINE, and PsycINFO databases on May 28-29, 2015. We hand-searched the journal LGBT Health. Inclusion criteria were: systematic reviews and meta-analyses that addressed LGBT health, used systematic searching, and used independent coders for inclusion. The published search terminology in each record and search strings provided by authors on request were cross-referenced with our original search to identify additional terminology. Our search process identified 19 systematic reviews meeting inclusion criteria. The number of search terms used to identify LGBT-related records ranged from 1 to 31. From the included studies, we identified 46 new search terms related to LGBT health. We removed five search terms as inappropriate and added five search terms used in the field. The resulting search string included 82 terms. There is room to improve the quality of searching and reporting in LGBT health systematic reviews. Future work should attempt to enhance the positive predictive value of LGBT health searches. Our findings can assist LGBT health reviewers in capturing the diversity of LGBT terminology when searching.

Topics: Bisexuality; Female; Homosexuality, Female; Homosexuality, Male; Humans; MEDLINE; Male; Minority Health; Research Design; Review Literature as Topic; Terminology as Topic; Transgender Persons; Transsexualism

PubMed: 27219460
DOI: 10.1371/journal.pone.0156210