Optimal HIV testing intervals in HIV‑negative individuals
Published by: The Public Health Agency of Canada
Issue: Volume 43-2: Sexually transmitted infections
Date published: February 2, 2017
Volume 43-2, February 2, 2017: Sexually transmitted infections
Evidence for optimal HIV testing intervals in HIV-negative individuals from various risk groups: a systematic review protocol
GP Traversy1, T Austin1, J Yau1, K Timmerman1,*
1 Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON
Traversy GP, Austin T, Yau J, Timmerman K. Evidence for optimal HIV testing intervals in HIV-negative individuals from various risk groups: a systematic review protocol. Can Commun Dis Rep. 2017;43(2):38-48. https://doi.org/10.14745/ccdr.v43i02a02
Background: Evidence-based recommendations for HIV testing are essential for health care providers. However, it is unclear whether there is sufficient evidence to support recommendations for HIV testing frequencies in a variety of HIV risk groups.
Objective: The aim of this document is to outline the methodological protocol of a systematic review that would gather evidence for the optimal frequency of HIV testing among individuals in various HIV risk groups with respect to personal and public health outcomes and cost-effectiveness.
Methods: This protocol adheres to the PRISMA-P reporting items, and the review is registered with PROSPERO. The target population includes individuals who may have undiagnosed HIV infection. Different frequencies of HIV testing will be compared and outcomes to do with personal and public health, patient values/preferences and costs will be examined. The search strategy will encompass searches in MEDLINE/Pubmed, Scopus, Embase, Cochrane, PsychINFO, and EconLit, as well as grey literature sources. Articles will be screened by title/abstract, and subsequently by full-text, in duplicate. Extraction of pertinent data from the screened references will be carried out by one reviewer and verified by a second. Multiple critical appraisal tools will be used to assess individual study quality, and the GRADE approach will be used to appraise the overall quality of the evidence. Data will be synthesized narratively, and the results will be published in a peer-reviewed journal.
Discussion: This systematic review, designed with extensive input from content experts, will help to identify key evidence to inform recommendations for HIV testing frequency.
HIV testing is a key element of the HIV cascade of care, representing the first “90” of the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90–90–90 global strategy for addressing HIV/AIDS Footnote 1. HIV diagnosis is essential for linkage to care and initiation of antiretroviral therapy (ART), which may subsequently lead to decreased viral load, reduced infectivity and improved personal health outcomes Footnote 2Footnote 3. Low rates of screening and testing are therefore a potential limiting factor for the success of HIV prevention strategies. Up to 50% of new HIV infections may be attributed to those who are unaware of their infection Footnote 4Footnote 5Footnote 6Footnote 7. In Canada, it is estimated that individuals who are unaware of their infection represent 21% of all those who are HIV-infected Footnote 8.
Certain populations who are at higher risk for HIV infection, such as men who have sex with men (MSM), injection drug users (IDU) or Indigenous peoples, may benefit from more frequent HIV testing. Accordingly, an important question in developing recommendations and strategies for HIV testing is how often should individuals from different risk groups be tested for HIV. Answering this question requires balancing the potential benefits of enhanced screening with the increased costs of the screening, as well as considerations of patient values and preferences.
Clear and specific guidance for how often to test individuals from different risk groups may help health care providers improve their testing behaviours and normalize this practice. A recent systematic review of guidelines found that a number of the guidelines recommend annual screening for groups including MSM and IDU but that others cite a paucity of data frequency of testing for HIV in certain groups, leading to some inconsistencies in guidance Footnote 9. At the federal level, the Public Health Agency of Canada’s HIV Screening and Testing Guide states that individuals involved in high-risk practices should be screened for HIV at least annually but that there is insufficient evidence to provide recommendations for individual scenarios Footnote 10.
Many of the guidelines reviewed in the systematic review of guidelines mentioned above are several years old. In addition, guideline developers do not always describe the basis for their recommendations (e.g. systematic review versus expert opinion). A thorough, up-to-date review of scientific evidence related to HIV testing frequency is warranted and will be useful for developing timely quality guidance in Canada and abroad. The purpose of this article is to describe the protocol for a systematic review aimed at answering a number of questions related to how often to test for HIV.
The objective of the systematic review is to examine the scientific evidence that supports different frequencies of HIV testing for individuals in various risk groups who may have undiagnosed HIV.
The over-arching research question is: What is the optimal frequency of testing for HIV in individuals from various HIV risk groups with respect to personal and public health outcomes and cost-effectiveness? The sub-questions relevant to this include:
- What is the most effective frequency or interval of testing for HIV in people who have unknown or previously confirmed negative serostatus, with respect to personal/public health outcomes?
- What are patients’ values and preferences with respect to how often to test/re-test for HIV?
- What are the potential harms associated with different HIV testing frequencies?
- What is the most cost-effective frequency or interval of re-testing for HIV in people who have an unknown or a previously confirmed negative serostatus?
Prior to the development of this protocol, a scoping search was completed to help guide protocol development and identify any similar works. This scoping search included a review of the reference lists from key guidelines identified in a systematic review of HIV testing guidelines Footnote 9 as well as searches for the term “HIV testing” on the websites of the following organizations/registries: Cochrane, the National Institute for Health and Care Excellence (NICE), the Canadian Agency for Drugs and Technologies in Health (CADTH), the UK Department of Health (NHS), the International Resource for Infection Control (iNRIC) and the PROSPERO International Prospective Register of systematic reviews.
This systematic review protocol has been designed in alignment with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) Footnote 11. See Appendix 1 for a list of the PRISMA-P reporting items.
Drafts of the protocol were peer-reviewed by several experts in infectious disease guideline development from the Public Health Agency of Canada prior to registration of the review with the PROSPERO International Prospective Register of systematic reviews (registration number CRD42016046575) Footnote 12. In addition, a health economist was consulted.
A comprehensive search strategy was designed in consultation with a research librarian. The search strategy was also peer-reviewed by an external research librarian prior to execution of the search. The full search strategy can be found in Appendix 2.
The following databases will be searched:
- Cochrane Library
The following sources of grey literature will be searched:
- Open Grey
- All relevant sources from the CADTH Grey Matters checklist Footnote 13
The search strategies that will be used for Open Grey and ClinicalTrials.gov can be found in Appendix 3.
The CADTH Grey Matters tool is a checklist used to guide online searches for grey literature. It includes national and international health technology assessment websites, drug and device regulatory agencies, clinical trial registries, health economics resources, Canadian health prevalence or incidence databases and drug formulary web sites Footnote 13. A total of 40 relevant websites from the checklist were identified by the research team (drug formulary, drug advisory and warning, and surveillance databases were not considered relevant to the research question, for example). Many of the websites in the checklist do not include an advanced search option, so the large majority will be searched using the term “HIV” to provide the widest range of potentially relevant results. Websites with advanced search functions will be searched with combinations of “HIV” and “testing” or “screening” or “test” or “screen.”
Grey literature searches will be carried out by two members of the research team independently, and all articles deemed potentially relevant will be added to the results of the database searches for further screening.
All references will be uploaded into the DistillerSR, a secure, internet-based systematic review management software (Evidence Partners). This software platform will be used for screening eligible articles, data extraction and quality assessment.
Articles published in English or French will be considered for the review.
Eligible study designs will vary depending on the specific research sub-question. For all search questions, other systematic reviews will not be explicitly excluded. Rather, the reference lists will be scanned for relevant articles that may have otherwise been missed.
Table 1 outlines the study designs that will be considered for each of the research sub-questions.
|Research sub-question||Eligible study designs|
|With respect to personal/public health outcomes, what is the most effective frequency or interval of re-testing for HIV in people who have unknown or previously confirmed negative serostatus?||Quantitative (particularly comparative) studies:
|What are patients’ values and preferences with respect to how often to test/re-test for HIV?||Qualitative studies
|What are the potential harms associated with different HIV testing frequencies?||Quantitative and qualitative studies will be considered|
|What is the most cost-effective frequency or interval of re-testing for HIV in people who have an unknown or a previously confirmed negative serostatus?||Costing studies:
The target population includes individuals who may have undiagnosed HIV infection.
The intervention of interest is HIV screening/testing at varying intervals.
The effects of the intervention will be compared to any the following:
- Other interventions
- “Normal” or “standard” state of care (as defined in a given study)
- Before/after comparisons
Studies will be considered if they are held in any setting where HIV testing could be conducted.
Articles will also be excluded if they are:
- Published prior to 2000
- Commentaries, editorials, letters to the editor, conference abstracts, poster presentations
- Guidelines/policy papers/policy documents
Several potential outcomes that could be relevant for each of the research sub-questions have been identified. However, the possibility exists that not all of the outcomes will be represented in the literature, as some may not have been examined. The primary and secondary outcomes of interest for each research question are outlined in Table 2.
|With respect to personal/public health outcomes, what is the most effective frequency or interval of re-testing for HIV in people who have unknown or previously confirmed negative serostatus?||Primary outcomes:
|What are patients’ values and preferences with respect to how often to test/re-test for HIV?||
|What are the potential harms associated with different HIV testing frequencies?||
|What is the most cost-effective frequency or interval of re-testing for HIV in people who have an unknown or a previously confirmed negative serostatus?||
Screening/selection of articles
All references identified in the search will be screened based on title and abstract following removal of duplicates. The eligibility criteria above will be used to determine inclusion and exclusion of articles at the title/abstract-screening stage. Screening of titles and abstracts will be performed in duplicate by two reviewers. Disagreements will be reconciled through discussion with a third reviewer.
Full-text screening will be performed on titles with abstracts that meet the above criteria or for cases in which it is unclear whether this is the case. At the full-text screening stage, the eligibility criteria, as well as the outcomes listed above, will guide exclusion of irrelevant articles. Full-text screening will be performed in duplicate by two reviewers. Disagreements will be reconciled through discussion with a third reviewer.
Reasons for exclusion will be recorded at each step of the screening process. The results of the screening will be presented in a flowchart consistent with PRISMA recommendations Footnote 14.
Extraction of pertinent data from the screened references will be carried out by one reviewer and verified by another in order to reduce bias or errors in extraction. Any disagreements will be resolved through discussion with one or two other reviewers. Study authors may be contacted if there are any major uncertainties. All pertinent data (i.e. year of publication, period of data collection, study population, sample size, location, study setting, study design, intervention, comparison, results/outcomes, quality assessment score, etc.) will be extracted into evidence tables.
Duplicate, overlapping or companion studies, if identified during the screening process, will be dealt with by extracting the data into a single collection form or by extracting the data separately and combining these into a single input afterwards, as per the Cochrane Handbook for Systematic Reviews of Interventions Footnote 15.
Quality assessment will be carried out for individual studies included in the review, as well as for the overall body of evidence. Different methods of assessment will be used as appropriate for the study type.
The following assessment tools will be used for individual studies:
- Cochrane risk of bias for RCTs Footnote 15
- Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for other quantitative studies Footnote 16Footnote 17Footnote 18
- Critical Appraisal Skills Programme (CASP) Qualitative Checklist for qualitative studies Footnote 19
For the overall body of evidence, the quality of evidence will be assessed using the GRADE approach Footnote 15.
Data will be synthesized narratively. If there is sufficient homogeneity among the evidence, a meta-analysis may be considered, although this is unlikely due to the variety of evidence sources being sought.
The initial search will not target any specific subgroups. If evidence emerges for specific subgroups (e.g. MSM, IDU, Indigenous peoples, etc.) then the results will be disaggregated and reported narratively in separate sections for each subgroup.
Assessment of meta-biases
Statistical assessment of meta-biases such as publication bias across studies (e.g. Egger’s test) will likely not be possible given the wide variety of evidence being sought and the likelihood of inclusion of a large proportion of studies with observational designs Footnote 20. The potential for publication bias will however be reduced by employing a rigorous search of grey literature, and the potential for substantial publication bias in observational studies will be taken into account when assessing the overall body of evidence using the GRADE approach Footnote 20. Selective outcome reporting will be assessed in RCTs by comparing the reported results of studies with the outcomes reported in the methods section of the protocol of the study. This will factor into quality assessment with the Cochrane risk of bias tool Footnote 15.
The research team does not foresee any amendments to the protocol prior to carrying out the systematic review. However, if this is necessary, all amendments will be recorded as they occur and reflected in the PROSPERO record for this review. Amendments will also be documented in the final publication.
A manuscript of the results of the systematic review will be prepared and submitted for publication in a peer-reviewed journal. The results will be presented according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines Footnote 14.
To the best of our knowledge, this will be the first published systematic review examining evidence supporting recommendations for HIV testing frequency. The evidence identified in this review may be useful to update or create new guidance around HIV testing in Canada; groups outside Canada may also find it useful. The development of specific, evidence-based recommendations will help health care providers streamline and improve their HIV testing practices. Such recommendations can also be used by the public to manage their own sexual health.
Enhanced HIV screening and testing will help decrease the substantial portion of individuals with HIV who are unaware of their infection. This group contributes to a substantial proportion of new HIV infections, and evidence suggests that once these individuals are aware of their infection, they will be more likely to take steps to minimize the likelihood of transmission Footnote 4Footnote 21. HIV diagnosis is also the first step toward obtaining treatment, and thus, enhanced screening and testing yields benefits for personal and public health.
The strengths of this systematic review protocol include extensive input from content experts in the development of HIV and sexually transmitted infection guidelines and health economics. Another strength is the external peer review of the research librarian–designed search strategy.
One limitation of the review could be the potential inclusion of predominantly observational studies, given the difficulty of carrying out experimental studies on the topic. This may raise concerns regarding the quality of evidence; however, the results of the quality assessments will be published, and thus assessment of bias in the evidence will be transparent.
If this systematic review fails to find evidence to answer one or more of the research questions, this will be documented in the results. A “negative” finding will still be of use to guideline developers as it provides validity to those guidelines that cite a lack of evidence for HIV-testing interval recommendations Footnote 9 and suggests that such recommendations may need to be made on a jurisdiction-by-jurisdiction basis, based on expert opinion. It would also help highlight gaps in evidence, which could be useful for guiding future research.
We would like to thank Michèle Sabourin, Kelsey Young, Lisa Pogany, Rachel Bennett, Ulrick Auguste, Cathy Latham-Carmanico, Bakhtiar Anwar, Jun Wu and Margaret Gale-Rowe for their constructive review and feedback on the draft protocol. We would also like to thank the research librarians, Connie Barrowclough and Katherine Merucci, who helped design and carry out our systematic search, and Margaret Sampson for peer-reviewing the search strategy.
KT is the guarantor. GT drafted the protocol for the review, and all authors made substantial contributions to refine the research question/sub-questions, the study eligibility and exclusion criteria, the outcomes of interest, the screening, extraction and quality assessment processes, and the search strategy (with the help of a trained research librarian). GT, TA and JY will draft the manuscript. All authors will read, provide feedback and approve the final manuscript.
Conflict of interest
This study was supported by the Public Health Agency of Canada. The authors have no sources of external funding to declare.
Appendix 1: Completed PRISMA-P checklist for the systematic review
|Section and topic||Item||Checklist item||Line no(s).|
|Identification||1a||Identify the report as a protocol of a systematic review||1, 67|
|Update||1b||If the protocol is for an update of a previous systematic review, identify as such||N/A|
|Registration||2||If registered, provide the name of the registry (such as PROSPERO) and registration number||103|
|Contact||3a||Provide name, institutional affiliation, email address of all protocol authors; provide physical mailing address of corresponding author||4-7|
|Contributions||3b||Describe contributions of protocol authors and identify the guarantor of the review||262-267|
|Amendments||4||If the protocol represents an amendment of a previously completed or published protocol, identify as such and list changes; otherwise, state plan for documenting important protocol amendments||220-224|
|Sources||5a||Indicate sources of financial or other support for the review||270-273|
|Sponsor||5b||Provide name for the review funder and/or sponsor||270-273|
|Role of sponsor or funder||5c||Describe roles of funder(s), sponsor(s) and/or institution(s), if any, in developing the protocol||N/A|
|Rationale||6||Describe the rationale for the review in the context of what is already known||52-68|
|Objectives||7||Provide an explicit statement of the question(s) the review will address with reference to participants, interventions, comparators, and outcomes (PICO)||151-174|
|Eligibility criteria||8||Specify the study characteristics (such as PICO, study design, setting, time frame) and report characteristics (such as years considered, language, publication status) to be used as criteria for eligibility for the review||140-174|
|Information sources||9||Describe all intended information sources (such as electronic databases, contact with study authors, trial registers or other grey literature sources) with planned dates of coverage||109-129, 145, 191-192|
|Search strategy||10||Present draft of search strategy to be used for at least one electronic database, including planned limits, so that it could be repeated||344|
|Data management||11a||Describe the mechanism(s) that will be used to manage records and data throughout the review||137|
|Selection process||11b||State the process that will be used for selecting studies (such as two independent reviewers) through each phase of the review (that is, screening, eligibility and inclusion in meta-analysis)||175-187|
|Data collection process||11c||Describe planned method of extracting data from reports (such as piloting forms, done independently, in duplicate), any processes for obtaining and confirming data from investigators||188-199|
|Data items||12||List and define all variables for which data will be sought (such as PICO items, funding sources), any pre-planned data assumptions and simplifications||192-194|
|Outcomes and prioritization||13||List and define all outcomes for which data will be sought, including prioritization of main and additional outcomes, with rationale||173|
|Risk of bias in individual studies||14||Describe anticipated methods for assessing risk of bias of individual studies, including whether this will be done at the outcome or study level, or both; state how this information will be used in data synthesis||200-209|
|Data synthesis||15a||Describe criteria under which study data will be quantitatively synthesized||213|
|15b||If data are appropriate for quantitative synthesis, describe planned summary measures, methods of handling data and methods of combining data from studies, including any planned exploration of consistency (such as I2, Kendall’s τ)||N/A|
|15c||Describe any proposed additional analyses (such as sensitivity or subgroup analyses, meta-regression)||216-219|
|15d||If quantitative synthesis is not appropriate, describe the type of summary planned||212-219|
|Meta-bias(es)||16||Specify any planned assessment of meta-bias(es) (such as publication bias across studies, selective reporting within studies)||220-229|
|Confidence in cumulative evidence||17||Describe how the strength of the body of evidence will be assessed (such as GRADE)||210-211|
Appendix 2: Search Strategy
All searches run and downloaded on September 16, 2016.
|1||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).af.||1713|
|2||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").af.||91581|
|3||(freque* or interval*).af.||26404|
|4||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test* or retest* or depistage or "diagnostic du VIH")).af.||1484|
|5||1 and 2 and 3||5|
|6||1 and 4||2|
|8||limit 7 to yr="2000 -Current"||6|
|2||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).ti.||27738|
|3||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).ab. /freq=2||31713|
|8||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").ti.||102858|
|9||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").ab. /freq=2||258239|
|12||(freque* or interval*).ti.||22666|
|13||(freque* or interval*).ab. /freq=2||91053|
|15||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test* or retest* or depistage or "diagnostic du VIH")).ti.||575|
|16||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test* or retest* or depistage or "diagnostic du VIH")).ab. /freq=2||918|
|18||(10 and 14) or 17||10859|
|19||4 and 18||197|
|20||11 and (14 or 17)||69|
|24||case report/ or case report.tw.||36249|
|26||21 not 25||176|
|27||limit 26 to yr="2000 -Current"||164|
|1||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).ti,kf.||204027|
|2||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).ab. /freq=2||178603|
|3||exp HIV Infections/||252533|
|9||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").ti,kf.||470662|
|10||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").ab. /freq=2||935790|
|13||(freque* or interval*).ti,kf.||132544|
|14||(freque* or interval*).ab. /freq=2||521701|
|16||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH")).ti,kf.||2150|
|17||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH")).ab. /freq=2||2569|
|19||(11 and 15) or 18||54568|
|20||6 and 19||1580|
|21||12 and (15 or 18)||157|
|22||20 or 21||1610|
|23||(letter or editorial).pt.||1360656|
|26||24 not (24 and 25)||4284662|
|27||case reports/ or case report.tw.||1885376|
|29||22 not 28||1567|
|30||limit 29 to yr="2000 -Current"||1171|
Scopus: Run September 16, 2016
TITLE ( "hiv" OR "hiv1" OR "hiv2 " OR "hivaids" OR "human immune deficiency virus" OR "human immunodeficiency virus" OR "virus de l'immunodeficience humaine" OR "vih" OR "vih1" OR "vih2" )
AND ( ( TITLE ( ( time OR timing OR moment OR temps OR often OR souvent* ) W/3 ( screen* OR rescreen* OR test OR tests OR tested OR testing OR retest* OR "diagnostic du VIH" OR depistage ) ) ) OR ( ( TITLE-ABS ( screen* OR rescreen* OR test OR tests OR tested OR testing OR retest* OR "diagnostic du VIH" OR depistage ) )
AND ( TITLE-ABS ( freque* OR interval* ) ) ) )
AND ( PUBYEAR > 1999 )
AND SUBJAREA ( mult OR arts OR busi OR deci OR econ OR psyc OR soci )
|1||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).ti,kw.||246105|
|2||(hiv or hiv+ or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or (human immun* adj2 virus) or virus de l'immunodeficience humaine or vih or vih+ or vih1 or vih2 or vih-1 or vih-2).ab. /freq=2||204295|
|3||exp Human immunodeficiency virus infection/||328710|
|4||exp Human immunodeficiency virus/||160405|
|5||Human immunodeficiency virus antigen/||1810|
|6||Human immunodeficiency virus antibody/||8917|
|7||Human immunodeficiency virus infected patient/||26547|
|14||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").ti,kw.||608987|
|15||(screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH").ab. /freq=2||1265723|
|17||exp hiv test/||6818|
|18||(freque* or interval*).ti,kw.||162041|
|19||(freque* or interval*).ab. /freq=2||651528|
|21||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH")).ti,kw.||2617|
|22||((time or timing or moment or temps or often or souvent*) adj3 (screen* or rescreen* or test or tests or testing or tested or retest* or depistage or "diagnostic du VIH")).ab. /freq=2||3598|
|24||(16 and 20) or 23||81929|
|25||8 and 24||2539|
|26||17 and (20 or 23)||316|
|28||(letter or editorial).pt.||1480511|
|31||29 not (29 and 30)||1350042|
|32||case study/ or case report.tw.||362306|
|34||27 not 33||2557|
|35||limit 34 to yr="2000 -Current"||2174|
|#1||[mh "HIV Infections"] or [mh HIV]||9272|
|#2||[mh ^"HIV Antibodies"]||238|
|#3||(hiv or hiv-1 or hiv-2 or hiv1 or hiv2 or hivaids or human immune deficiency virus or human immunodeficiency virus or human immuno-deficiency virus or human immune-deficiency virus or virus de l'immunodeficience humaine or vih or vih1 or vih2 or vih-1 or vih-2):ti||9923|
|#4||#1 or #2 or #3||12575|
|#5||[mh ^"mass screening"] or [mh ^"serologic tests"]||4877|
|#6||(screen* or rescreen* or test or tests or tested or testing or retest* or depistage or "diagnostic du VIH"):ti||21763|
|#7||#5 or #6||22979|
|#8||(freque* or interval*):ti||6568|
|#9||((time or timing or moment or temps or souvent*) near/3 (screen* or rescreen* or test or tests or tested or testing or retest* or "diagnostic du VIH" or depistage)):ti||147|
|#10||#8 or #9||6710|
|#11||[mh ^"AIDS serodiagnosis"]||143|
|#12||(#7 and #8) or #9||332|
|#13||#10 and #11||3|
|#14||#4 and #12||17|
|#15||#13 or #14 Publication Year from 2000 to 2016||3|
Appendix 3: Grey Literature Searches
All grey literature searches run on October 27, 2016
("HIV" OR "HIV+" or "HIV-1" OR "HIV-2" OR "HIV1" OR "HIV2" OR "HIVAIDS" OR ("human immun*" NEAR/2 "virus") OR "human immunodeficiency virus" OR "human immunodeficiency virus infection") AND ("screening" OR "test*" OR "retest*" OR "rescreen*" OR "re-test*" OR “re-screen*")
Results: 163 items returned
Conditions: "HIV" OR "HIV+" or "HIV-1" OR "HIV-2" OR "HIV1" OR "HIV2" OR "HIVAIDS" OR "human immununodeficiency virus"
Interventions: "screening" OR "testing" OR "retesting" OR "rescreening" OR "re-testing" OR "re-screening"
Timeframe: Studies received on or after 01/01/2000
Results: 649 items returned
Report a problem or mistake on this page
- Date modified: