Last data update: May 06, 2024. (Total: 46732 publications since 2009)
Records 1-30 (of 31 Records) |
Query Trace: Frost M[original query] |
---|
Database derived from an electronic medical record-based surveillance network of US emergency department patients with acute respiratory illness
Kline JA , Reed B , Frost A , Alanis N , Barshay M , Melzer A , Galbraith JW , Budd A , Winn A , Pun E , Camargo CA Jr . BMC Med Inform Decis Mak 2023 23 (1) 224 BACKGROUND: For surveillance of episodic illness, the emergency department (ED) represents one of the largest interfaces for generalizable data about segments of the US public experiencing a need for unscheduled care. This protocol manuscript describes the development and operation of a national network linking symptom, clinical, laboratory and disposition data that provides a public database dedicated to the surveillance of acute respiratory infections (ARIs) in EDs. METHODS: The Respiratory Virus Laboratory Emergency Department Network Surveillance (RESP-LENS) network includes 26 academic investigators, from 24 sites, with 91 hospitals, and the Centers for Disease Control and Prevention (CDC) to survey viral infections. All data originate from electronic medical records (EMRs) accessed by structured query language (SQL) coding. Each Tuesday, data are imported into the standard data form for ARI visits that occurred the prior week (termed the index file); outcomes at 30 days and ED volume are also recorded. Up to 325 data fields can be populated for each case. Data are transferred from sites into an encrypted Google Cloud Platform, then programmatically checked for compliance, parsed, and aggregated into a central database housed on a second cloud platform prior to transfer to CDC. RESULTS: As of August, 2023, the network has reported data on over 870,000 ARI cases selected from approximately 5.2 million ED encounters. Post-contracting challenges to network execution have included local shifts in testing policies and platforms, delays in ICD-10 coding to detect ARI cases, and site-level personnel turnover. The network is addressing these challenges and is poised to begin streaming weekly data for dissemination. CONCLUSIONS: The RESP-LENS network provides a weekly updated database that is a public health resource to survey the epidemiology, viral causes, and outcomes of ED patients with acute respiratory infections. |
Modeling effectiveness of testing strategies to prevent COVID-19 in nursing homes —United States, 2020 (preprint)
See I , Paul P , Slayton RB , Steele MK , Stuckey MJ , Duca L , Srinivasan A , Stone N , Jernigan JA , Reddy SC . medRxiv 2021 2020.12.18.20248255 Background SARS-CoV-2 outbreaks in nursing homes can be large with high case fatality. Identifying asymptomatic individuals early through serial testing is recommended to control COVID-19 in nursing homes, both in response to an outbreak (“outbreak testing” of residents and healthcare personnel) and in facilities without outbreaks (“non-outbreak testing” of healthcare personnel). The effectiveness of outbreak testing and isolation with or without non-outbreak testing was evaluated.Methods Using published SARS-CoV-2 transmission parameters, the fraction of SARS-CoV-2 transmissions prevented through serial testing (weekly, every three days, or daily) and isolation of asymptomatic persons compared to symptom-based testing and isolation was evaluated through mathematical modeling using a Reed-Frost model to estimate the percentage of cases prevented (i.e., “effectiveness”) through either outbreak testing alone or outbreak plus non-outbreak testing. The potential effect of simultaneous decreases (by 10%) in the effectiveness of isolating infected individuals when instituting testing strategies was also evaluated.Results Modeling suggests that outbreak testing could prevent 54% (weekly testing with 48-hour test turnaround) to 92% (daily testing with immediate results and 50% relative sensitivity) of SARS-CoV-2 infections. Adding non-outbreak testing could prevent up to an additional 8% of SARS-CoV-2 infections (depending on test frequency and turnaround time). However, added benefits of non-outbreak testing were mostly negated if accompanied by decreases in infection control practice.Conclusions When combined with high-quality infection control practices, outbreak testing could be an effective approach to preventing COVID-19 in nursing homes, particularly if optimized through increased test frequency and use of tests with rapid turnaround.Summary Mathematical modeling evaluated the effectiveness of serially testing asymptomatic persons in a nursing home in response to a SARS-CoV-2 outbreak with or without serial testing of asymptomatic staff in the absence of known SARS-CoV-2 infections.Competing Interest StatementThe authors have declared no competing interest.Funding StatementNo external funding was received. All work was conducted as part of government duties.Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy (see e.g., 45 C.F.R. part 46, 21 C.F.R. part 56; 42 U.S.C. 241(d); 5 U.S.C 552a; 44 U.S.C. 351 et seq.).All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesData provided in supplemental materials or publicly available through links in the manuscript. https://github.com/cdcepi/Nursing-home-SARS-CoV-2-testing-model/ |
Genome-wide patterns of gene expression in a wild primate indicate species-specific mechanisms associated with tolerance to natural simian immunodeficiency virus infection (preprint)
Simons ND , Eick GN , Ruiz-Lopez MJ , Hyeroba D , Omeja PA , Weny G , Chapman CA , Goldberg TL , Zheng H , Shankar A , Switzer WM , Frost SDW , Jones JH , Sterner KN , Ting N . bioRxiv 2018 395152 Over 40 species of nonhuman primates host simian immunodeficiency viruses (SIVs). In natural hosts, infection is generally assumed to be nonpathogenic due to a long coevolutionary history between host and virus, although pathogenicity is difficult to study in wild nonhuman primates. We used whole-blood RNA-seq and SIV prevalence from 29 wild Ugandan red colobus (Piliocolobus tephrosceles) to assess the effects of SIV infection on host gene expression in wild, naturally SIV-infected primates. We found no evidence for chronic immune activation in infected individuals, suggesting that SIV is not immunocompromising in this species, in contrast to HIV in humans. Notably, an immunosuppressive gene, CD101, was upregulated in infected individuals. This gene has not been previously described in the context of nonpathogenic SIV infection. This expands the known variation associated with SIV infection in natural hosts, and may suggest a novel mechanism for tolerance of SIV infection in the Ugandan red colobus. |
Phylogenomic analysis uncovers a 9-year variation of Uganda influenza type-A strains from the WHO-recommended vaccines and other Africa strains.
Nabakooza G , Owuor DC , de Laurent ZR , Galiwango R , Owor N , Kayiwa JT , Jjingo D , Agoti CN , Nokes DJ , Kateete DP , Kitayimbwa JM , Frost SDW , Lutwama JJ . Sci Rep 2023 13 (1) 5516 Genetic characterisation of circulating influenza viruses directs annual vaccine strain selection and mitigation of infection spread. We used next-generation sequencing to locally generate whole genomes from 116 A(H1N1)pdm09 and 118 A(H3N2) positive patient swabs collected across Uganda between 2010 and 2018. We recovered sequences from 92% (215/234) of the swabs, 90% (193/215) of which were whole genomes. The newly-generated sequences were genetically and phylogenetically compared to the WHO-recommended vaccines and other Africa strains sampled since 1994. Uganda strain hemagglutinin (n = 206), neuraminidase (n = 207), and matrix protein (MP, n = 213) sequences had 95.23-99.65%, 95.31-99.79%, and 95.46-100% amino acid similarity to the 2010-2020 season vaccines, respectively, with several mutated hemagglutinin antigenic, receptor binding, and N-linked glycosylation sites. Uganda influenza type-A virus strains sequenced before 2016 clustered uniquely while later strains mixed with other Africa and global strains. We are the first to report novel A(H1N1)pdm09 subclades 6B.1A.3, 6B.1A.5(a,b), and 6B.1A.6 (± T120A) that circulated in Eastern, Western, and Southern Africa in 2017-2019. Africa forms part of the global influenza ecology with high viral genetic diversity, progressive antigenic drift, and local transmissions. For a continent with inadequate health resources and where social distancing is unsustainable, vaccination is the best option. Hence, African stakeholders should prioritise routine genome sequencing and analysis to direct vaccine selection and virus control. |
An outbreak investigation of Salmonella typhimurium illnesses in the United States linked to packaged leafy greens produced at a controlled environment agriculture indoor hydroponic operation - 2021
McClure M , Whitney B , Gardenhire I , Crosby A , Wellman A , Patel K , McCormic ZD , Gieraltowski L , Gollarza L , Low MSF , Adams J , Pightling A , Bell RL , Nolte K , Tijerina M , Frost JT , Beix JA , Boegler KA , Dow J , Altman S , Wise ME , Bazaco MC , Viazis S . J Food Prot 2023 86 (5) 100079 In 2021, the U.S. Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and state partners investigated a multistate outbreak of Salmonella Typhimurium illnesses linked to packaged leafy greens from a controlled environment agriculture (CEA) operation in Illinois. Thirty-one illnesses and four hospitalizations were reported in four states, with a significant epidemiologic signal for packaged leafy greens from Farm A. A traceback investigation for leafy greens included seven points of service (POS) with food exposure data from eight ill people. Each POS was supplied leafy greens by Farm A. FDA investigators observed operations at Farm A and noted that 1) the firm did not consider their indoor hydroponic pond water as agricultural water, 2) condensate dripping from the chiller water supply line inside the building, and 3) unprotected outdoor storage of packaged soilless growth media and pallets used for finished product. FDA collected 25 product, water, and environmental samples from Farm A. The outbreak strain was recovered from a water sample collected from a stormwater drainage basin located on the property adjacent to Farm A. In addition, an isolate of Salmonella Liverpool was recovered from two indoor growing ponds within the same growing house, but no illnesses were linked to the isolate. Farm A voluntarily recalled all implicated products and provided their root cause analysis (RCA) and return-to-market plan to FDA. While the source and route of the contamination were not determined by the RCA, epidemiologic and traceback evidence confirmed the packaged salads consumed by ill persons were produced by Farm A. This was the first investigation of a multistate foodborne illness outbreak associated with leafy greens grown in a CEA operation. This outbreak demonstrated the need for growers using hydroponic methods to review their practices for potential sources and routes of contamination and to reduce food safety risks when identified. |
Lessons from the pandemic: Responding to emerging zoonotic viral diseases-a Keystone Symposia report
Cable J , Fauci A , Dowling WE , Günther S , Bente DA , Yadav PD , Madoff LC , Wang LF , Arora RK , Van Kerkhove M , Chu MC , Jaenisch T , Epstein JH , Frost SDW , Bausch DG , Hensley LE , Bergeron É , Sitaras I , Gunn MD , Geisbert TW , Muñoz-Fontela C , Krammer F , de Wit E , Nordenfelt P , Saphire EO , Gilbert SC , Corbett KS , Branco LM , Baize S , van Doremalen N , Krieger MA , Clemens SAC , Hesselink R , Hartman D . Ann N Y Acad Sci 2022 1518 (1) 209-225 The COVID-19 pandemic caught the world largely unprepared, including scientific and policy communities. On April 10-13, 2022, researchers across academia, industry, government, and nonprofit organizations met at the Keystone symposium "Lessons from the Pandemic: Responding to Emerging Zoonotic Viral Diseases" to discuss the successes and challenges of the COVID-19 pandemic and what lessons can be applied moving forward. Speakers focused on experiences not only from the COVID-19 pandemic but also from outbreaks of other pathogens, including the Ebola virus, Lassa virus, and Nipah virus. A general consensus was that investments made during the COVID-19 pandemic in infrastructure, collaborations, laboratory and manufacturing capacity, diagnostics, clinical trial networks, and regulatory enhancements-notably, in low-to-middle income countries-must be maintained and strengthened to enable quick, concerted responses to future threats, especially to zoonotic pathogens. |
Amoxicillin versus other antibiotic agents for the treatment of acute otitis media in children
Frost HM , Bizune D , Gerber JS , Hersh AL , Hicks LA , Tsay SV . J Pediatr 2022 251 98-104 e5 OBJECTIVES: To compare the antibiotic treatment failure and recurrence rates between antibiotic agents (amoxicillin, amoxicillin-clavulanate, cefdinir, and azithromycin) for children with uncomplicated acute otitis media (AOM) STUDY DESIGN: We completed a retrospective cohort study of children 6 months-12 years of age with uncomplicated AOM identified in a nationwide claims database. The primary exposure was antibiotic agent, and the primary outcomes were treatment failure and recurrence. Logistic regression was used to estimate odds ratios and analyses were stratified by primary exposure, patient age and antibiotic duration. RESULTS: Among the 1,051,007 children included in the analysis, 56.6% were prescribed amoxicillin, 13.5% amoxicillin-clavulanate, 20.6% cefdinir, and 9.3% azithromycin. Most prescriptions (93%) were for 10 days and 98% were filled within 1 day of the medical encounter. Treatment failure or recurrence occurred in 2.2% (95%CI: 2.1, 2.2) and 3.3% (3.2, 3.3) of children, respectively. Combined failure and recurrence rates were low for all agents including amoxicillin (1.7%; 1.7, 1.8) amoxicillin-clavulanate 11.3% (11.1, 11.5); cefdinir 10.0% (9.8, 10.1); azithromycin 9.8% (9.6, 10.0). CONCLUSIONS: Despite microbiologic changes in AOM etiology, treatment failure and recurrence were uncommon for all antibiotic agents and were lower for amoxicillin than for other agents. These findings support the continued use of amoxicillin as a first-line agent for AOM when antibiotics are prescribed. |
Trends in unit sales of cooling flavoured e-cigarettes, USA, 2017-2021
Ali FRM , Seaman EL , Diaz MC , Ajose J , King BA . Tob Control 2022 OBJECTIVE: Flavours that produce a cooling sensation, such as menthol, enhance the appeal of e-cigarettes among youth; but not all e-cigarettes that produce cooling sensations are labelled as menthol. This study assessed trends in unit sales of cooling flavoured e-cigarettes in the USA. DESIGN: E-cigarette retail sales during 26 January 2017 to 28 November 2021 were licensed from Information Resources, Inc, which records brick-and-mortar retail scanner sales but not online or vape shop sales. Cooling flavours were identified using six descriptors: menthol, ice, cool, chill, freeze or frost; ambiguous flavours were verified using online searches. Cooling flavours were categorised by characterising flavour (menthol, mint, other) and product type (prefilled cartridges, disposables, e-liquids). Joinpoint regression was used to assess sales and price trends. RESULTS: During January 2017 to November 2021, unit sales of cooling flavoured e-cigarettes increased by 693.0% (1.5 to 12.0 million units); the percentage of these sales from total sales increased from 26.4% to 54.9%. Among cooling flavours, percentage of menthol sales decreased from 94.5% to 73.0% (p<0.001). Among menthol cooling flavours, percentage of prefilled cartridges increased from 67.2% to 96.6% (p<0.001); among non-menthol cooling flavours, percentage of disposable e-cigarettes increased from 5.2% to 99.2% (p<0.001). There were no significant price differences between cooling and non-cooling flavoured disposable e-cigarettes. CONCLUSION: The percentage of cooling flavoured e-cigarette sales from total sales doubled during 2017-2021, and sales of non-menthol cooling disposable e-cigarettes experienced the highest percentage increase. Cooling flavoured e-cigarettes are important to consider when developing strategies to address flavoured e-cigarette use among youth. |
Financial navigation: Staff perspectives on patients' financial burden of cancer care
Yeager KA , Zahnd WE , Eberth JM , Vanderpool RC , Rohweder C , Teal R , Vu M , Stradtman L , Frost EL , Trapl E , Gonzalez SK , Vu T , Ko LK , Cole A , Farris PE , Shannon J , Askelson N , Seegmiller L , White A , Edward J , Davis M , Petermann V , Wheeler SB . J Cancer Surviv 2022 PURPOSE: To describe perceptions of financial navigation staff concerning patients' cancer-related financial burden. METHODS: This qualitative descriptive study used a semi-structured interview guide to examine perceptions of financial navigation staff concerning patients' cancer-related financial burden. Staff who provided financial navigation support services to cancer patients were interviewed from different types of cancer programs across seven states representing rural, micropolitan, and urban settings. Interviews lasted approximately one hour, were audio recorded, and transcribed. Transcripts were double coded for thematic analysis. RESULTS: Thirty-five staff from 29 cancer centers were interviewed. The first theme involved communication issues related to patient and financial navigation staff expectations, timing and the sensitive nature of financial discussions. The second theme involved the multi-faceted impact of financial burden on patients, including stress, difficulty adhering to treatments, and challenges meeting basic, non-medical needs. CONCLUSIONS AND IMPLICATIONS FOR CANCER SURVIVORS: Cancer-related financial burden has a profound impact on cancer survivors' health and non-health outcomes. Discussions regarding cancer-related costs between cancer survivors and healthcare team members could help to normalize conversations and mitigate the multi-faceted determinants and effects of cancer-related financial burden. As treatment may span months and years and unexpected costs arise, having this discussion regularly and systematically is needed. |
How cancer programs identify and address the financial burdens of rural cancer patients
Petermann V , Zahnd WE , Vanderpool RC , Eberth JM , Rohweder C , Teal R , Vu M , Stradtman L , Frost E , Trapl E , Koopman Gonzalez S , Vu T , Ko LK , Cole A , Farris PE , Shannon J , Lee J , Askelson N , Seegmiller L , White A , Edward J , Davis M , Wheeler SB . Support Care Cancer 2021 30 (3) 2047-2058 PURPOSE: Financial toxicity is associated with negative patient outcomes, and rural populations are disproportionately affected by the high costs of cancer care compared to urban populations. Our objective was to (1) understand cancer programs' perceptions of rural-urban differences in cancer patients' experiences of financial hardship, (2) evaluate the resources available to cancer patients across the rural-urban continuum, and (3) determine how rural and urban health care teams assess and address financial distress in cancer patients. METHODS: Seven research teams within the Cancer Prevention and Research Control Network conducted semi-structured interviews with cancer program staff who have a role in connecting cancer patients with financial assistance services in both rural and urban counties. Interviews were audio-recorded and transcribed. We identified themes using descriptive content and thematic analysis. RESULTS: We interviewed 35 staffs across 29 cancer care programs in seven states, with roughly half of respondents from programs in rural counties. Participants identified differences in rural and urban patients' experiences of financial hardship related to distance required to travel for treatment, underinsurance, and low socioeconomic status. Insufficient staffing was an identified barrier to addressing rural and urban patients' financial concerns. CONCLUSIONS: Improved financial navigation services could mitigate the effects of financial toxicity experienced by cancer patients, particularly rural patients, throughout treatment and survivorship. Future research is needed to improve how cancer programs assess financial hardship in patients and to expand financial navigation services to better serve rural cancer patients. |
Program Adaptations to Provide Harm Reduction Services During the COVID-19 Pandemic: A Qualitative Study of Syringe Services Programs in the U.S.
Frost MC , Sweek EW , Austin EJ , Corcorran MA , Juarez AM , Frank ND , Prohaska SM , LaKosky PA , Asher AK , Broz D , Jarlais DCD , Williams EC , Glick SN . AIDS Behav 2021 26 (1) 57-68 Syringe services programs (SSPs) are essential to preventing injection drug use-related infections and overdose death among people who use drugs (PWUD). The novel coronavirus (COVID-19) pandemic initially impeded SSPs' operations. To effectively support these programs, information is needed regarding SSPs' experiences adapting their services and the challenges posed by COVID-19. We conducted qualitative interviews with leadership and staff from a sample of 31 U.S. SSPs. Respondents discussed urgent concerns including reduced reach of services, suspended HIV/hepatitis C testing, high COVID-19 risk among PWUD, and negative impacts of isolation on overdose and mental health. They also noted opportunities to improve future services for PWUD, including shifting to evidence-based distribution practices and maintaining regulatory changes that increased access to opioid use disorder medications post-pandemic. Findings can inform efforts to support SSPs in restoring and expanding services, and provide insight into SSPs' role in engaging PWUD during the COVID-19 response and future emergencies. |
Intersection of Syphilis and HIV Networks to Identify Opportunities to Enhance HIV Prevention.
Dennis AM , Cressman A , Pasquale D , Frost SDW , Kelly E , Guy J , Mobley V , Samoff E , Hurt CB , McNeil C , Hightow-Weidman L , Carry M , Hogben M , Seña AC . Clin Infect Dis 2021 74 (3) 498-506 BACKGROUND: HIV and syphilis infection continue at disproportionate rates among minority men who have sex with men (MSM) in the United States. The integration of HIV genetic clustering with partner services can provide important insight into local epidemic trends to guide interventions and control efforts. METHODS: We evaluated contact networks of index persons defined as minority men and transgender women diagnosed with early syphilis and/or HIV infection between 2018-2020 in two North Carolina regions. HIV clusters were constructed from pol sequences collected through statewide surveillance. A combined "HIV-risk" network, which included persons with any links (genetic or sexual contact) to HIV-positive persons, was evaluated by component size, demographic factors, and HIV viral suppression. RESULTS: In total, 1,289 index persons were identified and 55% named 1,153 contacts. Most index persons were Black (88%) and young (median age 30 years); 70% had early syphilis and 43% had prevalent HIV infection. Most people with HIV (65%) appeared in an HIV cluster. The combined HIV-risk network (1,590 contact network and 1,500 cluster members) included 287 distinct components; however, 1,586 (51%) were in a single component. Fifty-five percent of network members with HIV had no evidence of viral suppression. Overall, fewer index persons needed to be interviewed to identify one HIV-positive member without viral suppression (1.3 versus 4.0 for contact tracing). CONCLUSIONS: Integration of HIV clusters and viral loads illuminate networks with high HIV prevalence, indicating recent and ongoing transmission. Interventions intensified towards these networks may efficiently reach persons for HIV prevention and care re-engagement. |
Improving Delayed Antibiotic Prescribing for Acute Otitis Media
Frost HM , Monti JD , Andersen LM , Norlin C , Bizune DJ , Fleming-Dutra KE , Czaja CA . Pediatrics 2021 147 (6) OBJECTIVES: Acute otitis media (AOM) is the most-common indication for antibiotics in children. Delayed antibiotic prescribing for AOM can significantly reduce unnecessary antibiotic use and is recommended by the American Academy of Pediatrics for select children. We sought to improve delayed prescribing for AOM across 8 outpatient pediatric practices in Colorado. METHODS: Through a collaborative initiative with American Academy of Pediatrics and the Centers for Disease Control and Prevention, we implemented an economical 6-month antimicrobial stewardship intervention that included education, audit and feedback, online resources, and content expertise. Practices used The Model for Improvement and plan-do-study-act cycles to improve delayed antibiotic prescribing. Generalized estimating equations were used to generate relative risk ratios (RRRs) for outcomes at the intervention end and 3- and 6-months postintervention. Practice surveys were evaluated. RESULTS: In total, 69 clinicians at 8 practice sites implemented 27 plan-do-study-act cycles. Practices varied by size (range: 6-37 providers), payer type, and geographic setting. The rate of delayed antibiotic prescribing increased from 2% at baseline to 21% at intervention end (RRR: 8.96; 95% confidence interval [CI]: 4.68-17.17). Five practices submitted postintervention data. The rate of delayed prescribing at 3 months and 6 months postintervention remained significantly higher than baseline (3 months postintervention, RRR: 8.46; 95% CI: 4.18-17.11; 6 months postintervention, RRR: 6.69; 95% CI: 3.53-12.65) and did not differ from intervention end (3 months postintervention, RRR: 1.12; 95% CI: 0.62-2.05; 6-months postintervention, RRR: 0.89; 95% CI: 0.53-1.49). CONCLUSIONS: Baseline rate of delayed prescribing was low. A low-cost intervention resulted in a significant and sustained increase in delayed antibiotic prescribing across a diversity of settings. |
Smoking and cessation behaviors in patients at federally funded health centers - United States, 2014
Trapl ES , VanFrank B , Kava CM , Trinh V , Land SR , Williams RS , Frost E , Babb S . Drug Alcohol Depend 2021 221 108615 BACKGROUND: Federally funded health centers (HCs) provide care to the most vulnerable populations in the U.S., including populations with disproportionately higher smoking prevalence such as those with lower incomes. METHODS: This study compared characteristics of adult HC patients, by cigarette smoking status, and assessed smoking cessation-related behaviors using 2014 Health Center Patient Survey data; analysis was restricted to adults with data on cigarette smoking status (n = 5583). Chi-square and logistic regression analyses were conducted. RESULTS: Overall, 28.1 % were current smokers and 19.2 % were former smokers. Current smokers were more likely to report fair/poor health (48.2 %) and a high burden of behavioral health conditions (e.g., severe psychological distress 23.9 %) versus former and never smokers. Most current smokers reported wanting to quit in the past 12 months (79.0 %) and receiving advice to quit from a healthcare professional (78.7 %). In a multivariable model, age <45, non-white race, COPD diagnosis, and past 3-month marijuana use were significantly associated with desire to quit. Few former smokers (15.2 %) reported using cessation treatment, though use was higher among those who quit within the previous year (30.6 %). CONCLUSIONS: Although most current smokers reported a desire to quit, low uptake of evidence-based treatment may reduce the number who attempt to quit and succeed. Given the burden of tobacco use, future efforts could focus on identifying and overcoming unique personal, healthcare professional, or health system barriers to connecting them with cessation treatments. Increasing access to cessation treatments within HCs could reduce smoking-related disparities and improve population health. |
Modeling effectiveness of testing strategies to prevent COVID-19 in nursing homes -United States, 2020.
See I , Paul P , Slayton RB , Steele MK , Stuckey MJ , Duca L , Srinivasan A , Stone N , Jernigan JA , Reddy SC . Clin Infect Dis 2021 73 (3) e792-e798 BACKGROUND: SARS-CoV-2 outbreaks in nursing homes can be large with high case fatality. Identifying asymptomatic individuals early through serial testing is recommended to control COVID-19 in nursing homes, both in response to an outbreak ("outbreak testing" of residents and healthcare personnel) and in facilities without outbreaks ("non-outbreak testing" of healthcare personnel). The effectiveness of outbreak testing and isolation with or without non-outbreak testing was evaluated. METHODS: Using published SARS-CoV-2 transmission parameters, the fraction of SARS-CoV-2 transmissions prevented through serial testing (weekly, every three days, or daily) and isolation of asymptomatic persons compared to symptom-based testing and isolation was evaluated through mathematical modeling using a Reed-Frost model to estimate the percentage of cases prevented (i.e., "effectiveness") through either outbreak testing alone or outbreak plus non-outbreak testing. The potential effect of simultaneous decreases (by 10%) in the effectiveness of isolating infected individuals when instituting testing strategies was also evaluated. RESULTS: Modeling suggests that outbreak testing could prevent 54% (weekly testing with 48-hour test turnaround) to 92% (daily testing with immediate results and 50% relative sensitivity) of SARS-CoV-2 infections. Adding non-outbreak testing could prevent up to an additional 8% of SARS-CoV-2 infections (depending on test frequency and turnaround time). However, added benefits of non-outbreak testing were mostly negated if accompanied by decreases in infection control practice. CONCLUSIONS: When combined with high-quality infection control practices, outbreak testing could be an effective approach to preventing COVID-19 in nursing homes, particularly if optimized through increased test frequency and use of tests with rapid turnaround. |
An investig-ation into the epidemiology of chikungunya virus across neglected regions of Indonesia.
Stubbs SCB , Johar E , Yudhaputri FA , Yohan B , Santoso MS , Hayati RF , Denis D , Blacklaws BA , Powers AM , Sasmono RT , Myint KSA , Frost SDW . PLoS Negl Trop Dis 2020 14 (12) e0008934 BACKGROUND: Chikungunya virus (CHIKV) is an important emerging and re-emerging public health problem worldwide. In Indonesia, where the virus is endemic, epidemiological information from outside of the main islands of Java and Bali is limited. METHODOLOGY/PRINCIPAL FINDINGS: Four hundred and seventy nine acutely febrile patients presenting between September 2017-2019 were recruited from three city hospitals situated in Ambon, Maluku; Banjarmasin, Kalimantan; and Batam, Batam Island as part of a multi-site observational study. CHIKV RNA was detected in a single serum sample while a separate sample was IgM positive. IgG seroprevalence was also low across all three sites, ranging from 1.4-3.2%. The single RT-PCR positive sample from this study and 24 archived samples collected during other recent outbreaks throughout Indonesia were subjected to complete coding region sequencing to assess the genetic diversity of Indonesian strains. Phylogenetic analysis revealed all to be of a single clade, which was distinct from CHIKV strains recently reported from neighbouring regions including the Philippines and the Pacific Islands. CONCLUSIONS/SIGNIFICANCE: Chikungunya virus strains from recent outbreaks across Indonesia all belong to a single clade. However, low-level seroprevalence and molecular detection of CHIKV across the three study sites appears to contrast with the generally high seroprevalences that have been reported for non-outbreak settings in Java and Bali, and may account for the relative lack of CHIKV epidemiological data from other regions of Indonesia. |
Updated emm-typing protocol for Streptococcus pyogenes.
Frost HR , Davies MR , Velusamy S , Delforge V , Erhart A , Darboe S , Steer A , Walker MJ , Beall B , Botteaux A , Smeesters PR . Clin Microbiol Infect 2020 26 (7) 946 e5-946 e8 OBJECTIVES: PCR-based typing of the emm gene Streptococcus pyogenes often results in the amplification of multiple bands. This has resulted in the misclassification of strains into types based on non-emm gene sequences. We aimed to improve the specificity of the emm typing PCR reaction using a primer called CDC3, the sequence for which has been previously used to identify emm genes in silico. METHODS: The proposed primer CDC3 was validated in silico from a global database of 1688 GAS genomes and in vitro with 32 isolates. PCR reactions were performed on genomic DNA from each isolate, using the published CDC1 forward primer with the CDC2 reverse primer or the new CDC3 reverse primer. The products were examined by gel electrophoresis, and representative PCR products were sequenced. RESULTS: In 1688 S. pyogenes genomes, the previous CDC2 reverse primer annealed in silico in 1671 emm genes and also in 2109 non emm genes in close proximity, whereas the new CDC3 primer annealed in 1669 emm genes only. The remaining 19 genes without a CDC3 binding site were chimeric emm genes. The PCR pair CDC1+CDC3 produced a single band at appropriate molecular weight in all 32 isolates tested, while the CDC1+CDC2 pair produced more than one band in 13 of 32 isolates (40%). CONCLUSIONS: The new CDC3 primer is more specific for emm genes than the previous CDC2 primer and represents a simple solution to reduce the potential for mistyping S. pyogenes strains. |
Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins.
Frost HR , Davies MR , Delforge V , Lakhloufi D , Sanderson-Smith M , Srinivasan V , Steer AC , Walker MJ , Beall B , Botteaux A , Smeesters PR . mSphere 2020 5 (1) The core Mga (multiple gene activator) regulon of group A Streptococcus (GAS) contains genes encoding proteins involved in adhesion and immune evasion. While all GAS genomes contain genes for Mga and C5a peptidase, the intervening genes encoding M and M-like proteins vary between strains. The genetic make-up of the Mga regulon of GAS was characterized by utilizing a collection of 1,688 GAS genomes that are representative of the global GAS population. Sequence variations were examined with multiple alignments, and the expression of all core Mga regulon genes was examined by quantitative reverse transcription-PCR in a representative strain collection. In 85.2% of the sampled genomes, the Mga locus contained genes encoding Mga, Mrp, M, Enn, and C5a peptidase proteins. These isolates account for 53% of global infections. Only 9.1% of genomes did not contain either an mrp or an enn gene. The pairwise identity within Enn (68.6%) and Mrp (83.2%) protein sequences was higher than within M proteins (44.7%). Gene expression varied between strains tested, but high expression was recorded for all genes in at least one strain. Previous nomenclature issues were clarified with molecular gene definitions. Our findings support a shift in focus in the GAS research field to further consider the role of Mrp and Enn in virulence and vaccine development.IMPORTANCE While the GAS M protein has been the leading vaccine target for decades, the bacteria encode many other virulence factors of interest for vaccine development. In this work, we show that emm-like genes are encoded in a remarkable majority of GAS genomes and expressed at a level similar to that for the emm gene. In collaboration with the U.S. Centers for Disease Control, we developed molecular definitions of the different emm and emm-like gene families. This clarification should abrogate mistyping of strains, especially in the area of whole-genome typing. We have also updated the emm-typing collection by removing emm-like gene sequences and provided in-depth analysis of Mrp and Enn protein sequence structure and diversity. |
Sustaining outpatient antimicrobial stewardship: Do we need to think further outside the box
Frost HM , Andersen LM , Fleming-Dutra KE , Norlin C , Czaja CA . Infect Control Hosp Epidemiol 2020 41 (3) 1-3 Antibiotic overuse is a persistent public health problem that has contributed to an alarming increase in the prevalence of antibiotic resistance.1 In the United States, >70% of antibiotic courses are prescribed in ambulatory settings.2 To encourage the appropriate use of antibiotics in outpatient practices, the Centers for Disease Control and Prevention (CDC) released the Core Elements of Outpatient Antibiotic Stewardship (hereafter Core Elements).3 However, detailed evaluations of how practices implement and sustain the Core Elements are lacking. |
Clinical practice guideline for the diagnosis, evaluation, and treatment of attention-deficit/hyperactivity disorder in children and adolescents
Wolraich ML , Hagan JFJr , Allan C , Chan E , Davison D , Earls M , Evans SW , Flinn SK , Froehlich T , Frost J , Holbrook JR , Lehmann CU , Lessin HR , Okechukwu K , Pierce KL , Winner JD , Zurhellen W . Pediatrics 2019 144 (4) Attention-deficit/hyperactivity disorder (ADHD) is 1 of the most common neurobehavioral disorders of childhood and can profoundly affect children's academic achievement, well-being, and social interactions. The American Academy of Pediatrics first published clinical recommendations for evaluation and diagnosis of pediatric ADHD in 2000; recommendations for treatment followed in 2001. The guidelines were revised in 2011 and published with an accompanying process of care algorithm (PoCA) providing discrete and manageable steps by which clinicians could fulfill the clinical guideline's recommendations. Since the release of the 2011 guideline, the Diagnostic and Statistical Manual of Mental Disorders has been revised to the fifth edition, and new ADHD-related research has been published. These publications do not support dramatic changes to the previous recommendations. Therefore, only incremental updates have been made in this guideline revision, including the addition of a key action statement related to diagnosis and treatment of comorbid conditions in children and adolescents with ADHD. The accompanying process of care algorithm has also been updated to assist in implementing the guideline recommendations. Throughout the process of revising the guideline and algorithm, numerous systemic barriers were identified that restrict and/or hamper pediatric clinicians' ability to adopt their recommendations. Therefore, the subcommittee created a companion article (available in the Supplemental Information) on systemic barriers to the care of children and adolescents with ADHD, which identifies the major systemic-level barriers and presents recommendations to address those barriers; in this article, we support the recommendations of the clinical practice guideline and accompanying process of care algorithm. |
Progress in public health risk communication in China: Lessons learned from SARS to H7N9
Frost M , Li R , Moolenaar R , Mao Q , Xie R . BMC Public Health 2019 19 475 Background: Following the SARS outbreak, the World Health Organization revised the International Health Regulations to include risk communication as one of the core capacity areas. In 2006, the U.S. Centers for Disease Control and Prevention's Global Disease Detection [GDD] program began collaborating with China to enhance China's risk communication capacity to address gaps in the SARS communication response. This article describes tangible improvements in China's public health emergency risk communication capacity between the SARS and H7N9 outbreaks; documents U.S. CDC GDD cooperative technical assistance during 2006-2017; and shares lessons learnt to benefit other countries and contribute to enhance global health security. Method: A questionnaire based on the WHO Joint External Evaluation tool [Risk Communication section] was developed. A key communications official from the China National Health Commission [NHC] completed the questionnaire retrospectively to reflect China's capacity to manage communication response before, during and after the outbreaks of SARS in 2003, influenza H1N1 in 2009, and influenza H7N9 in 2013. A literature search was also conducted in English and Chinese to further substantiate the results of the questionnaire completed by NHC. Results: China demonstrated significantly improved risk communication capacities of pre-event, during event and post event responses to H7N9 when compared to the SARS response. China NHC improved its response through preparedness, availability of dedicated staff and resources for risk communication, internal clearance mechanisms, standard operating procedures with national response parties external to NHC, rumor management, communication with international agencies and consistent messaging with healthcare and private sectors. Correspondingly, the perceived level of trust that the public had in the NHC following outbreaks rose between the SARS and H7N9 response. Conclusion: Risk communication capacities in China have increased during the ten years between the SARS outbreak of 2003 and the H7N9 outbreak of 2013. Long-term risk communication capacity building efforts in bilateral collaborations are uncommon. The U.S. CDC GDD project was one of the first such collaborations worldwide. The lessons learned from this project may benefit lower and middle-income countries as they build their national emergency risk communication capacity. |
Genome-wide patterns of gene expression in a wild primate indicate species-specific mechanisms associated with tolerance to natural simian immunodeficiency virus infection.
Simons ND , Eick GN , Ruiz-Lopez MJ , Hyeroba D , Omeja PA , Weny G , Chapman CA , Goldberg TL , Zheng H , Shankar A , Switzer WM , Frost SDW , Jones JH , Sterner KN , Ting N . Genome Biol Evol 2019 11 (6) 1630-1643 Over 40 species of nonhuman primates host simian immunodeficiency viruses (SIVs). In natural hosts, infection is generally assumed to be nonpathogenic due to a long coevolutionary history between host and virus, although pathogenicity is difficult to study in wild nonhuman primates. We used whole-blood RNA-seq and SIV prevalence from 29 wild Ugandan red colobus (Piliocolobus tephrosceles) to assess the effects of SIV infection on host gene expression in wild, naturally SIV-infected primates. We found no evidence for chronic immune activation in infected individuals, suggesting that SIV is not immunocompromising in this species, in contrast to HIV in humans. Notably, an immunosuppressive gene, CD101, was upregulated in infected individuals. This gene has not been previously described in the context of nonpathogenic SIV infection. This expands the known variation associated with SIV infection in natural hosts, and may suggest a novel mechanism for tolerance of SIV infection in the Ugandan red colobus. |
Perceptions on the risk communication strategy during the 2013 avian influenza A/H7N9 outbreak in humans in China: a focus group study
Li R , Xie R , Yang C , Frost M . Western Pac Surveill Response J 2016 7 (3) 21-28 OBJECTIVE: To identify the general public's perceptions of the overall risk communication strategy carried out by Chinese public health agencies during the first wave of avian influenza A(H7N9) outbreak in humans in 2013. METHODS: Participants were recruited from communities in Beijing, Lanzhou and Hangzhou, China in May and June 2013 by convenience sampling. Demographics and other relevant information were collected using a self-administered questionnaire. Focus group interviews were conducted using a set of nine pre-developed questions and a tested moderator guide. The interviews were audio recorded and were transcribed verbatim. The constant comparative method was used to identify trends and themes. RESULTS: A total of nine focus group interviews, with 94 participants recruited from nine communities, were conducted. Most participants received H7N9 information via television and the Internet. Most the participants appreciated the transparency and timeliness of the information released by the government. They expressed a sense of trust in the recommended public health advice and followed most of them. The participants suggested that the government release more information about clinical treatment outcomes, have more specific health recommendations that are practical to their settings and expand the use of new media channels for risk communication. CONCLUSION: The public perceived the overall risk communication strategy by the Chinese public health agencies as effective, though the moderator had a governmental agency title that might have biased the results. There is a need to expand the use of social media for risk communication in the future. |
Assessing commitment and reporting fidelity to a text message-based participatory surveillance in rural Western Uganda
Lester J , Paige S , Chapman CA , Gibson M , Holland Jones J , Switzer WM , Ting N , Goldberg TL , Frost SD . PLoS One 2016 11 (6) e0155971 Syndromic surveillance, the collection of symptom data from individuals prior to or in the absence of diagnosis, is used throughout the developed world to provide rapid indications of outbreaks and unusual patterns of disease. However, the low cost of syndromic surveillance also makes it highly attractive for the developing world. We present a case study of electronic participatory syndromic surveillance, using participant-mobile phones in a rural region of Western Uganda, which has a high infectious disease burden, and frequent local and regional outbreaks. Our platform uses text messages to encode a suite of symptoms, their associated durations, and household disease burden, and we explore the ability of participants to correctly encode their symptoms, with an average of 75.2% of symptom reports correctly formatted between the second and 11th reporting timeslots. Concomitantly we identify divisions between participants able to rapidly adjust to this unusually participatory style of data collection, and those few for whom the study proved more challenging. We then perform analyses of the resulting syndromic time series, examining the clustering of symptoms by time and household to identify patterns such as a tendency towards the within-household sharing of respiratory illness. |
Introduction: health equity among incarcerated female adolescents and adult women: infectious and other disease morbidity
LeBlanc TT , Reid L , Dean HD , Green Y . Women Health 2014 54 (8) 687-693 The number of persons under correctional supervision in the United States increased in the mid-1970s and peaked in 2009 (Bureau of Justice Statistics, 2013). Though in subsequent years, incarcerated populations declined slightly, the United States continues to have one of the highest rates of incarceration among developed nations, and in the world, with 1 in 4 American adults behind bars (Pew Center on the States, 2012). Though detained populations are predominantly male, in the past 30 years, the number of women inmates in correctional facilities has increased dramatically. From 1977–2004, the number of U.S. female prisoners serving more than a year grew by 757%, while during the same period, the number of male prisoners grew by 388% (Frost, Greene, & Pranis, 2006). The growth of women in jails and prisons has surpassed male inmate population growth in 50 states (Frost, Greene, & Pranis, 2006). From 2000 to 2009, the number of women incarcerated in state or federal prisons rose by 21.6%, compared to a 15.6% increase for men (Mauer, 2013). | Nationally, there are more than eight times as many women under correctional supervision as there were in 1980 (American Civil Liberties Union, 2006). The United States has the highest incarceration rate for women in the world. In 2006, the rate was approximately 123 per 100,000 for women, which is much higher than those of England (17 per 100,000), France (6 per 100,000), Russia (73 per 100,000), and Thailand (88 per 100,000) (Hartney, 2006). |
Establishing an enteric bacteria reference laboratory in Sierra Leone
Chattaway MA , Kamara A , Rhodes F , Kaffeta K , Jambai A , Alemu W , Islam MS , Freeman MM , Welfare W , Harding D , Samba AF , Abu M , Kamanda S , Grant K , Jenkins C , Nair S , Connell S , Siorvanes L , Desai S , Allen C , Frost M , Hughes D , Jeffrey Z , Gill N , Salter M . J Infect Dev Ctries 2014 8 (7) 933-41 In 2012, Sierra Leone experienced its worst cholera outbreak in over 15 years affecting 12 of the country's 13 districts. With limited diagnostic capability, particularly in bacterial culture, the cholera outbreak was initially confirmed by microbiological testing of clinical specimens outside of Sierra Leone. During 2012 - 2013, in direct response to the lack of diagnostic microbiology facilities, and to assist in investigating and monitoring the cholera outbreak, diagnostic and reference services were established in Sierra Leone at the Central Public Health Reference Laboratory focusing specifically on isolating and identifying Vibrio cholerae and other enteric bacterial pathogens. Sierra Leone is now capable of confirming cholera cases by reference laboratory testing. |
Assessing knowledge and application of emergency risk communication principles among public health workers in China
Cope JR , Frost M , Richun L , Xie R . Disaster Med Public Health Prep 2014 8 (3) 1-7 OBJECTIVE: Since 2003, the Chinese National Health and Family Planning Commission (formerly the Ministry of Health) has implemented changes to more effectively communicate risk during public health emergencies. In spite of ongoing improvements, provincial and sub-provincial leaders face barriers, such as established modes of operation, lack of training, shortage of trained risk communicators, and limited understanding and willingness of recipients to mitigate risks. METHODS: We assessed the current status of and barriers to risk communication knowledge and practice among public health practitioners in China. We designed the survey questionnaire to capture information related to the risk communication core capacities required by international health regulations and common risk communication principles. RESULTS: Our findings showed that risk communication training has successfully developed an awareness of risk communication principles and the ability to implement those principles in practice in China. CONCLUSIONS: Future efforts should focus on areas such as a dedicated risk communication workforce, requirements that public health agencies develop a risk communication plan, and additional training for public health practitioners and their partners. It is critical that the infectious diseases prevention and control law be amended to grant provincial and local public health agencies more autonomy to release information. |
Collection efficiencies of high flow rate personal respirable samplers when measuring Arizona road dust and analysis of quartz by X-ray diffraction
Stacey P , Lee T , Thorpe A , Roberts P , Frost G , Harper M . Ann Occup Hyg 2014 58 (4) 512-23 Prolonged exposure to respirable crystalline silica (RCS) causes silicosis and is also considered a cause of cancer. To meet emerging needs for precise measurements of RCS, from shorter sampling periods (<4h) and lower air concentrations, collaborative work was done to assess the differences between personal respirable samplers at higher flow rates. The performance of FSP10, GK2.69, and CIP 10 R samplers were compared with that of the Safety In Mines Personal Dust Sampler (SIMPEDS) sampler as a reference, which is commonly used in the UK for the measurement of RCS. In addition, the performance of the FSP10 and GK 2.69 samplers were compared; at the nominal flow rates recommended by the manufacturers of 10 and 4.2 l . min(-1) and with flow rates proposed by the National Institute for Occupational Safety and Health of 11.2 and 4.4 l . min(-1). Samplers were exposed to aerosols of ultrafine and medium grades of Arizona road dust (ARD) generated in a calm air chamber. All analyses for RCS in this study were performed at the Health and Safety Laboratory. The difference in flow rates for the GK2.69 is small and does not result in a substantial difference in collection efficiency for the dusts tested, while the performance of the FSP10 at 11.2 l . min(-1) was more comparable with samples from the SIMPEDS. Conversely, the GK2.69 collected proportionately more crystalline silica in the respirable dust than other samplers, which then produced RCS results most comparable with the SIMPEDS. The CIP 10 R collected less ultrafine ARD than other samplers, as might be expected based on earlier performance evaluations. The higher flow rate for the FSP10 should be an added advantage for task-specific sampling or when measuring air concentrations less than current occupational exposure limits. |
Community-level text messaging for 2009 H1N1 prevention in China
Chai SJ , Tan F , Ji Y , Wei X , Li R , Frost M . Am J Prev Med 2013 45 (2) 190-6 BACKGROUND: Although patients worldwide increasingly are using mobile phone text messaging (SMS) for clinical care, quality data are sparse on the community-level effectiveness of SMS to prevent and control disease. PURPOSE: To determine SMS effectiveness in improving 2009 H1N1 knowledge, attitudes, behaviors, and self-reported outcomes and to assess community SMS acceptability. METHODS: A program evaluation of Shanghai, China's SMS system using a single-blinded, randomized-controlled method was conducted in 2010 and results were analyzed in 2010-2011. Randomly selected community residents who agreed to participate were assigned to receive 3 weeks of either 2009 H1N1 prevention and control or tobacco-cessation messages. Assessments were made of 2009 H1N1 knowledge, attitudes, behaviors, and self-reported influenza-like illness before and after sending messages to participants. Acceptability of SMS also was assessed. RESULTS: Of 1992 respondents, those receiving 2009 H1N1 messages had higher scores measuring 2009 H1N1 knowledge (4.2% higher) and desired attitudes (9.4% higher) (p<0.001); 1.77 times greater odds of new 2009 H1N1 vaccination (p<0.001); and 0.12 times smaller odds of reporting influenza-like illness (p<0.001) than those receiving tobacco messages. More than 95% of participants found the SMS program useful and trustworthy; nearly 90% would use it again. CONCLUSIONS: SMS can improve self-reported uptake of short-term behaviors, such as vaccination, that can result in long-term prevention and control of disease. SMS can improve knowledge and influence attitudes about infection prevention and control and self-reported health outcomes. In Shanghai, health-based SMS is acceptable to users. |
Respondent driven sampling--where we are and where should we be going?
White RG , Lansky A , Goel S , Wilson D , Hladik W , Hakim A , Frost SD . Sex Transm Infect 2012 88 (6) 397-9 Respondent Driven Sampling (RDS) is a novel variant of link tracing sampling that has primarily been used to estimate the characteristics of hard-to-reach groups, such as the HIV prevalence of drug users.1 ‘Seeds’ are selected by convenience from a population of interest (target population) and given coupons. Seeds then use these coupons to recruit other people, who themselves become recruiters. Recruits are given compensation, usually money, for taking part in the survey and also an incentive for recruiting others. This process continues in recruitment ‘waves’ until the survey is stopped. Estimation methods are then applied to account for the biased recruitment, for example, the presumed over-recruitment of people with more acquaintances, in an attempt to generate estimates for the underlying population. RDS has quickly become popular and relied on by major public health organisations, including the US Centers for Disease Control and Prevention and Family Health International, chiefly because it is often found to be an efficient method of recruitment in hard-to-reach groups, but also because of the availability of custom written software incorporating inference methods that are designed to generate estimates that are representative of the wider population of interest, despite the biased sampling. | As demonstrated by RDS's popularity,1 there was a clear need for new methods of data collection on hard-to-reach groups. However, RDS has not been without its critics. Its reliance on the target population for recruitment introduced ethicalw1 and sampling concerns.w2 If RDS estimates are overly biased or the variance is unacceptably high, then RDS will be little more than another method of convenience sampling. If these errors can be minimised however, then RDS has the potential to become a very useful survey methodology. |
- Page last reviewed:Feb 1, 2024
- Page last updated:May 06, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure