PubMed Health. A service of the National Library of Medicine, National Institutes of Health.

Tran K, Cimon K, Severn M, et al. Aerosol-Generating Procedures and Risk of Transmission of Acute Respiratory Infections: A Systematic Review [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2011 Nov.

3METHODS

3.1. Literature Search

Peer-reviewed literature searches were conducted to obtain published literature for this review. All search strategies were developed by the information specialist with input from the CADTH project team. Search terms were also reviewed by project team members from WHO and revised accordingly.

3.2. Technology Overview

The following bibliographic databases were searched through the Ovid interface: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, Embase, and CINAHL. Parallel searches were run in PubMed, The Cochrane Library (Issue 10, 2010), LILACS, Indian Medlars, and Index Medicus for South-East Asia Region. The search strategy comprised both controlled vocabulary, such as the National Library of Medicine’s MeSH (Medical Subject Headings), and keywords. Methodological filters were applied to limit the retrieval to health technology assessments, systematic reviews, meta-analyses, randomized controlled trials, non-randomized studies, and guidelines. See Appendix 1 for the detailed search strategies.

The search included all languages and was limited to articles published between Jan 1, 1990, and Oct 22, 2010. Conference abstracts were excluded from the search results. Regular alerts were established on Embase, MEDLINE, CINAHL, and PubMed, and information retrieved via alerts was current to Jan 15, 2011.

Grey literature (literature that is not commercially published) was identified by searching the websites of health technology assessment and related agencies, professional associations, and other specialized databases. Google and other Internet search engines were used to search for additional information. These searches were supplemented by handsearching the bibliographies and abstracts of key papers, and through contacts with appropriate experts and agencies.

3.3. Selection Criteria

Eligible studies included HTAs, systematic reviews, meta-analyses, randomized controlled trials, and non-randomized studies. The study population involved HCWs caring for patients with ARIs. The intervention was the provision of care to patients undergoing aerosol-generating procedures (exposed to the procedures). The comparator was the provision of care to patients not undergoing aerosol-generating procedures (unexposed to the procedures). The outcome of interest was the risk of transmission of ARIs from patients to HCWs. Procedures that might promote the generation of droplets or aerosols (non-exhaustive list) included non-invasive ventilation (CPAP, BiPAP), endotracheal intubation, airway suctioning, high-frequency oscillatory ventilation, bag-valve mask ventilation, chest physiotherapy, nebulizer therapies, aerosol humidification, bronchoscopy or other upper airway endoscopy, tracheotomy, and open thoracotomy.

3.4. Article Selection

Two reviewers (KT and KC) independently applied the selection criteria and screened all citation titles and abstracts that were retrieved from the literature search. The full texts of articles selected by either reviewer were obtained. The reviewers then independently reviewed the full text articles and selected studies for inclusion. The included and excluded studies were compared and any differences between reviewers were resolved by consensus. An independent third reviewer was available to determine final study selection in instances where consensus could not be reached. However, no studies required consultation with a third reviewer to determine whether they fit the inclusion criteria.

3.5. Data Extraction and Analysis

Relevant data from each of the individual studies were extracted by one reviewer (KT) and verified by a second reviewer (KC) using the pre-designed data extraction form to capture the study characteristics and the outcome of interest. The study characteristics included information about the origin of the study, the period of evaluation, the population, types of laboratory tests to confirm the diseases, and assessment of training and protection equipment use. The outcome of interest was the risk of disease transmission from patients to HCWs. Any disagreements between reviewers were resolved by consensus. An independent third reviewer was available to determine final data extraction in instances where consensus could not be reached. However, there were no data elements extracted that required consultation with a third reviewer to determine accuracy. Where appropriate, study results were pooled in a meta-analysis. The appropriateness of pooling of data was determined based upon the degree of clinical and statistical heterogeneity between trials. Where statistical heterogeneity was found (I2 > 25%), it was planned that sensitivity analyses on the summary treatment effect would be conducted. Pooling was also conducted separately for different types of design such as cohort and case-control studies. Data analysis was to be performed with Review Manager Software using a random effects model.18 Effect sizes were reported as odds ratios (OR) along with 95% confidence intervals (CI). A GRADE evaluation of the quality of evidence was performed, in which four keys elements (study design, study quality, consistency and directness) were considered.19

3.6. Peer Review

This report was peer reviewed by clinical experts from WHO and the Public Health Agency of Canada and internally by independent experts within CADTH. Feedback from these reviews was incorporated into the final report.

Copyright © 2011 CADTH.

This document may contain links to other information available on the websites of third parties on the Internet. CADTH does not have control over the content of such sites. Use of third-party sites is governed by the owners’ own terms and conditions set out for such sites. CADTH does not make any guarantee with respect to any information contained on such third-party sites and CADTH is not responsible for any injury, loss, or damage suffered as a result of using such third-party sites.

While the content of this document may be used in other jurisdictions, this disclaimer and any questions or matters of any nature arising from or relating to the content or use (or misuse) of this publication will be governed by and interpreted in accordance with the laws of the Province of Ontario and the laws of Canada applicable therein, and all proceedings shall be subject to the exclusive jurisdiction of the courts of the Province of Ontario, Canada.

Reproduction of this document for non-commercial purposes is permitted, provided it is not modified and appropriate credit is given to CADTH.

Except where otherwise noted, this work is distributed under the terms of a Creative Commons Attribution-NonCommercial- NoDerivatives 4.0 International licence (CC BY-NC-ND), a copy of which is available at http://creativecommons.org/licenses/by-nc-nd/4.0/

Cover of Aerosol-Generating Procedures and Risk of Transmission of Acute Respiratory Infections: A Systematic Review
Aerosol-Generating Procedures and Risk of Transmission of Acute Respiratory Infections: A Systematic Review [Internet].
Tran K, Cimon K, Severn M, et al.

PubMed Health Blog...

read all...

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...