9 research outputs found
Repairing boundaries along pathways to tuberculosis case detection: a qualitative synthesis of intervention designs
Background
Tuberculosis case-finding interventions often involve several activities to enhance patient pathways, and it is unclear which activity defines the type of case-finding intervention. When conducting studies to identify the most effective case-finding intervention it is important to have a clear understanding of these interventions for meaningful comparisons. This review aimed to construct a systems-based logic model of all pathways to tuberculosis case detection through a synthesis of intervention designs.
Methods
We identified an existing systematic review on the effectiveness of interventions to increase tuberculosis case detection and updated the search from December 2016 to October 2020. We included randomized controlled trials, as these designs encourage detailed description of interventions. Taking each study in turn, intervention descriptions were read in detail. The texts were analysed qualitatively by constantly comparing emerging codes to construct patient journeys, visualized as logical chains. Actions taken as part of interventions were positioned along patient journeys to theorize the sequence of outcomes. Patient journeys formed the basis of the model, which was refined through discussion.
Results
Based on intervention descriptions from 17 randomized controlled trials, our model distinguishes two care-seeking pathways and four screening pathways. An open invitation to people with tuberculosis symptoms creates care-seeking pathways. On care-seeking pathways, systematic screening can be conducted at general health services, but not at specific TB care services. People invited to tuberculosis services regardless of symptoms follow tuberculosis screening pathways and may be identified with presumptive tuberculosis even if they do not seek care for tuberculosis symptoms. Tuberculosis screening pathways include screening offered to all people accessing care at general health services, screening at a mobile clinic or health facility with open invitation to a whole population or tuberculosis contacts, screening personally offered to a whole population or tuberculosis contacts at home, work or school, and screening offered to people receiving care for human immunodeficiency virus or other clinical risk-group care.
Conclusion
This systems-based logic model of tuberculosis case-finding pathways may support standardized terminology, consistency, transparency and improved communication among researchers, policy-makers, health workers and community members when implementing and evaluating interventions to improve tuberculosis case detection
Community views on active case finding for tuberculosis in lowâ and middleâincome countries: a qualitative evidence synthesis
Background
Active case finding (ACF) refers to the systematic identification of people with tuberculosis in communities and amongst populations who do not present to health facilities, through approaches such as doorâtoâdoor screening or contact tracing. ACF may improve access to tuberculosis diagnosis and treatment for the poor and for people remote from diagnostic and treatment facilities. As a result, ACF may also reduce onward transmission. However, there is a need to understand how these programmes are experienced by communities in order to design appropriate services.
Objectives
To synthesize community views on tuberculosis active case finding (ACF) programmes in lowâ and middleâincome countries.
Search methods
We searched MEDLINE, Embase, and eight other databases up to 22 June 2023, together with reference checking, citation searching, and contact with study authors to identify additional studies. We did not include grey literature.
Selection criteria
This review synthesized qualitative research and mixedâmethods studies with separate qualitative data. Eligible studies explored community experiences, perceptions, or attitudes towards ACF programmes for tuberculosis in any endemic lowâ or middleâincome country, with no time restrictions.
Data collection and analysis
Due to the large volume of studies identified, we chose to sample studies that had 'thick' description and that investigated key subgroups of children and refugees. We followed standard Cochrane methods for study description and appraisal of methodological limitations. We conducted thematic synthesis and developed codes inductively using ATLAS.ti software. We examined codes for underlying ideas, connections, and interpretations and, from this, generated analytical themes. We assessed the confidence in the findings using the GRADEâCERQual approach, and produced a conceptual model to display how the different findings interact.
Main results
We included 45 studies in this synthesis, and sampled 20. The studies covered a broad range of World Health Organization (WHO) regions (Africa, SouthâEast Asia, Eastern Mediterranean, and the Americas) and explored the views and experiences of community members, community health workers, and clinical staff in lowâ and middleâincome countries endemic for tuberculosis. The following five themes emerged.
âą ACF improves access to diagnosis for many, but does little to help communities on the edge.
Tuberculosis ACF and contact tracing improve access to health services for people with worse health and fewer resources (High confidence). ACF helps to find this population, exposed to deprived living conditions, but is not sensitive to additional dimensions of their plight (High confidence) and outâofâpocket costs necessary to continue care (High confidence). Finally, migration and difficult geography further reduce communities' access to ACF (High confidence).
âą People are afraid of diagnosis and its impact.
Some community members find screening frightening. It exposes them to discrimination along distinct pathways (isolation from their families and wider community, lost employment and housing). HIV stigma compounds tuberculosis stigma and heightens vulnerability to discrimination along these same pathways (High confidence). Consequently, community members may refuse to participate in screening, contact tracing, and treatment (High confidence). In addition, people with tuberculosis reported their emotional turmoil upon diagnosis, as they anticipated intense treatment regimens and the prospect of living with a serious illness (High confidence).
âą Screening is undermined by weak health infrastructure.
In many settings, a lack of resources results in weak services in competition with other disease control programmes (Moderate confidence). In this context of low investment, people face repeated tests and clinic visits, wasted time, and fraught social interaction with health providers (Moderate confidence). ACF can create expectations for followâup health care that it cannot deliver (High confidence). Finally, community education improves awareness of tuberculosis in some settings, but lack of full information impacts community members, parents, and health workers, and sometimes leads to harm for children (High confidence).
âą Health workers are an undervalued but important part of ACF.
ACF can feel difficult for health workers in the context of a poorly resourced health system and with people who may not wish to be identified. In addition, the evidence suggests health workers are poorly protected against tuberculosis and fear they or their families might become infected (Moderate confidence). However, they appear to be central to programme success, as the humanity they offer often acts as a driving force for retaining people with tuberculosis in care (Moderate confidence).
âą Local leadership is necessary but not sufficient for ensuring appropriate programmes.
Local leadership creates an intrinsic motivation for communities to value health services (High confidence). However, local leadership cannot guarantee the success of ACF and contact tracing programmes. It is important to balance professional authority with local knowledge and rapport (High confidence).
Authors' conclusions
Tuberculosis active case finding (ACF) and contact tracing bring a diagnostic service to people who may otherwise not receive it, such as those who are well or without symptoms and those who are sick but who have fewer resources and live further from health facilities. However, capturing these 'missing cases' may in itself be insufficient without appropriate health system strengthening to retain people in care. People who receive a tuberculosis diagnosis must contend with a complex and unsustainable cascade of care, and this affects their perception of ACF and their decision to engage with it
Screening tests for active pulmonary tuberculosis in children
Objectives
This is a protocol for a Cochrane Review (diagnostic). The objectives are as follows:
To determine the sensitivity, specificity, and positive and negative predictive value of 1) the presence of one or more tuberculosis symptoms, or symptom combinations; 2) chest radiography; 3) Xpert MTB/RIF; 4) Xpert Ultra; and 5) combinations of the aforementioned tests as screening tests for detecting active pulmonary tuberculosis in children in the following groups.
Household contacts of a person with active tuberculosis;
School contacts of a person with active tuberculosis;
Other close contacts of a person with active tuberculosis;
Children living with HIV;
Children with pneumonia;
Other risk groups (e.g. children with a history of previous tuberculosis, malnourished children);
Children in the general population in high burden settings Secondary objectives
To compare the accuracy of the different index tests, including different applications of tests (e.g. CXR with any abnormality versus, more specifically, CXR with abnormality suggestive of tuberculosis); we are interested in the accuracy of the index tests in any setting (i.e. community, outpatient, and inpatient).
To investigate potential sources of heterogeneity in accuracy estimates in relation to age group, HIV status, whether the study was conducted in a high tuberculosis burden country, and whether the child received a single screening or more than one screening
Case-Finding Strategies for Drug-Resistant Tuberculosis: Protocol for a Scoping Review.
BACKGROUND
Transmission of drug-resistant tuberculosis (DR-TB) is ongoing. Finding individuals with DR-TB and initiating treatment as early as possible is important to improve patient clinical outcomes and to break the chain of transmission to control the pandemic. To our knowledge systematic reviews assessing effectiveness, cost-effectiveness, acceptability, and feasibility of different case-finding strategies for DR-TB to inform research, policy, and practice have not been conducted, and it is unknown whether enough research exists to conduct such reviews. It is unknown whether case-finding strategies are similar for DR-TB and drug-susceptible TB and whether we can draw on findings from drug-susceptible reviews to inform decisions on case-finding strategies for DR-TB.
OBJECTIVE
This protocol aims to describe the available literature on case-finding for DR-TB and to describe case-finding strategies.
METHODS
We will screen systematic reviews, trials, qualitative studies, diagnostic test accuracy studies, and other primary research that specifically sought to improve DR-TB case detection. We will exclude studies that invited individuals seeking care for TB symptoms, those including individuals already diagnosed with TB, or laboratory-based studies. We will search the academic databases including MEDLINE, Embase, The Cochrane Library, Africa-Wide Information, CINAHL, Epistemonikos, and PROSPERO with no language or date restrictions. We will screen titles, abstracts, and full-text articles in duplicate. Data extraction and analyses will be performed using Excel (Microsoft Corp).
RESULTS
We will provide a narrative report with supporting figures or tables to summarize the data. A systems-based logic model, developed from a synthesis of case-finding strategies for drug-susceptible TB, will be used as a framework to describe different strategies, resulting pathways, and enhancements of pathways. The search will be conducted at the end of 2021. Title and abstract screening, full text screening, and data extraction will be undertaken from January to June 2022. Thereafter, analysis will be conducted, and results compiled.
CONCLUSIONS
This scoping review will chart existing literature on case-finding for DR-TB-this will help determine whether primary studies on effectiveness, cost-effectiveness, acceptability, and feasibility of different case-finding strategies for DR-TB exist and will help formulate potential questions for a systematic review. We will also describe case-finding strategies for DR-TB and how they fit into a model of case-finding pathways for drug-susceptible TB. This review has some limitations. One limitation is the diverse, inconsistent use of intervention terminology within the literature, which may result in missing relevant studies. Poor reporting of intervention strategies may also cause misunderstanding and misclassification of interventions. Lastly, case-finding strategies for DR-TB may not fit into a model developed from strategies for drug-susceptible TB. Nevertheless, such a situation will provide an opportunity to refine the model for future research. The review will guide further research to inform decisions on case-finding policies and practices for DR-TB.
INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)
DERR1-10.2196/40009
Rapid, point-of-care antigen tests for diagnosis of SARS-CoV-2 infection
Accurate rapid diagnostic tests for SARS-CoV-2 infection would be a useful tool to help manage the COVID-19 pandemic. Testing strategies that use rapid antigen tests to detect current infection have the potential to increase access to testing, speed detection of infection, and inform clinical and public health management decisions to reduce transmission. This is the second update of this review, which was first published in 2020. To assess the diagnostic accuracy of rapid, point-of-care antigen tests for diagnosis of SARS-CoV-2 infection. We consider accuracy separately in symptomatic and asymptomatic population groups. Sources of heterogeneity investigated included setting and indication for testing, assay format, sample site, viral load, age, timing of test, and study design. We searched the COVID-19 Open Access Project living evidence database from the University of Bern (which includes daily updates from PubMed and Embase and preprints from medRxiv and bioRxiv) on 08 March 2021. We included independent evaluations from national reference laboratories, FIND and the Diagnostics Global Health website. We did not apply language restrictions. We included studies of people with either suspected SARS-CoV-2 infection, known SARS-CoV-2 infection or known absence of infection, or those who were being screened for infection. We included test accuracy studies of any design that evaluated commercially produced, rapid antigen tests. We included evaluations of single applications of a test (one test result reported per person) and evaluations of serial testing (repeated antigen testing over time). Reference standards for presence or absence of infection were any laboratory-based molecular test (primarily reverse transcription polymerase chain reaction (RT-PCR)) or pre-pandemic respiratory sample. We used standard screening procedures with three people. Two people independently carried out quality assessment (using the QUADAS-2 tool) and extracted study results. Other study characteristics were extracted by one review author and checked by a second. We present sensitivity and specificity with 95% confidence intervals (CIs) for each test, and pooled data using the bivariate model. We investigated heterogeneity by including indicator variables in the random-effects logistic regression models. We tabulated results by test manufacturer and compliance with manufacturer instructions for use and according to symptom status. We included 155 study cohorts (described in 166 study reports, with 24 as preprints). The main results relate to 152 evaluations of single test applications including 100,462 unique samples (16,822 with confirmed SARS-CoV-2). Studies were mainly conducted in Europe (101/152, 66%), and evaluated 49 different commercial antigen assays. Only 23 studies compared two or more brands of test. Risk of bias was high because of participant selection (40, 26%); interpretation of the index test (6, 4%); weaknesses in the reference standard for absence of infection (119, 78%); and participant flow and timing 41 (27%). Characteristics of participants (45, 30%) and index test delivery (47, 31%) differed from the way in which and in whom the test was intended to be used. Nearly all studies (91%) used a single RT-PCR result to define presence or absence of infection. The 152 studies of single test applications reported 228 evaluations of antigen tests. Estimates of sensitivity varied considerably between studies, with consistently high specificities. Average sensitivity was higher in symptomatic (73.0%, 95% CI 69.3% to 76.4%; 109 evaluations; 50,574 samples, 11,662 cases) compared to asymptomatic participants (54.7%, 95% CI 47.7% to 61.6%; 50 evaluations; 40,956 samples, 2641 cases). Average sensitivity was higher in the first week after symptom onset (80.9%, 95% CI 76.9% to 84.4%; 30 evaluations, 2408 cases) than in the second week of symptoms (53.8%, 95% CI 48.0% to 59.6%; 40 evaluations, 1119 cases). For those who were asymptomatic at the time of testing, sensitivity was higher when an epidemiological exposure to SARS-CoV-2 was suspected (64.3%, 95% CI 54.6% to 73.0%; 16 evaluations; 7677 samples, 703 cases) compared to where COVID-19 testing was reported to be widely available to anyone on presentation for testing (49.6%, 95% CI 42.1% to 57.1%; 26 evaluations; 31,904 samples, 1758 cases). Average specificity was similarly high for symptomatic (99.1%) or asymptomatic (99.7%) participants. We observed a steady decline in summary sensitivities as measures of sample viral load decreased. Sensitivity varied between brands. When tests were used according to manufacturer instructions, average sensitivities by brand ranged from 34.3% to 91.3% in symptomatic participants (20 assays with eligible data) and from 28.6% to 77.8% for asymptomatic participants (12 assays). For symptomatic participants, summary sensitivities for seven assays were 80% or more (meeting acceptable criteria set by the World Health Organization (WHO)). The WHO acceptable performance criterion of 97% specificity was met by 17 of 20 assays when tests were used according to manufacturer instructions, 12 of which demonstrated specificities above 99%. For asymptomatic participants the sensitivities of only two assays approached but did not meet WHO acceptable performance standards in one study each; specificities for asymptomatic participants were in a similar range to those observed for symptomatic people. At 5% prevalence using summary data in symptomatic people during the first week after symptom onset, the positive predictive value (PPV) of 89% means that 1 in 10 positive results will be a false positive, and around 1 in 5 cases will be missed. At 0.5% prevalence using summary data for asymptomatic people, where testing was widely available and where epidemiological exposure to COVID-19 was suspected, resulting PPVs would be 38% to 52%, meaning that between 2 in 5 and 1 in 2 positive results will be false positives, and between 1 in 2 and 1 in 3 cases will be missed. Antigen tests vary in sensitivity. In people with signs and symptoms of COVID-19, sensitivities are highest in the first week of illness when viral loads are higher. Assays that meet appropriate performance standards, such as those set by WHO, could replace laboratory-based RT-PCR when immediate decisions about patient care must be made, or where RT-PCR cannot be delivered in a timely manner. However, they are more suitable for use as triage to RT-PCR testing. The variable sensitivity of antigen tests means that people who test negative may still be infected. Many commercially available rapid antigen tests have not been evaluated in independent validation studies. Evidence for testing in asymptomatic cohorts has increased, however sensitivity is lower and there is a paucity of evidence for testing in different settings. Questions remain about the use of antigen test-based repeat testing strategies. Further research is needed to evaluate the effectiveness of screening programmes at reducing transmission of infection, whether mass screening or targeted approaches including schools, healthcare setting and traveller screening. [Abstract copyright: Copyright © 2022 The Authors. Cochrane Database of Systematic Reviews published by John Wiley & Sons, Ltd. on behalf of The Cochrane Collaboration.
The classification and geography of the flowering plants: Dicotyledons of the class Angiospermae
The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis
© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained â„1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32â0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88â1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62â0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61â0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine
Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries
This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London
Prospective observational cohort study on grading the severity of postoperative complications in global surgery research
Background
The ClavienâDindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the ClavienâDindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs).
Methods
This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using ClavienâDindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs.
Results
A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using ClavienâDindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59).
Conclusion
Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally