Mathilda Barnes

Johns Hopkins University, Baltimore, Maryland, United States

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Publications (46)113.01 Total impact

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    ABSTRACT: Background: Individuals who are sexually active may want to make a decision as to whether they are at risk for having a sexually transmitted infection (STI) such as Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis. Our goal was to develop and evaluate a simple self-taken sexual risk quiz for participants, ordering an online STI self-collection test kit to determine whether the score predicted infection status. Methods: As part of the IWantTheKit programme for home sample self-collection for STIs, 2010-2013, the programme asked male and female users to voluntarily take a risk quiz. The six-question quiz was about risk behaviour and included an age question. Data analyses were stratified by gender as determined a priori. Scores 0-10 were stratified into risk groups for each gender based on similar risk score-specific STI prevalence. Retrospective analyses were performed to assess whether risk group predicted aggregate STI positivity. Urogenital/rectal mailed samples were tested by nucleic acid amplification tests. Results: More females (N=836) than males (N=558) provided voluntary risk scores. The percentage of eligible participants who submitted scores was 43.9% for both females and males. There was a higher STI infection rate in females (14.0%) than in males (7.0%) for having any STI (p<0.001). Multivariate logistic analysis for females, which controlled for age and race, demonstrated that a higher risk score group independently predicted risk for having an STI (OR of 2.2 for risk scores 5-7 and 4.2 OR for scores of 8-10). For males, the multivariate model, which controlled for race, indicated that no risk score group was associated having an STI. Conclusions: Results of a participant's own sexual risk quiz score independently predicted STI positivity for women, but not for men. Further study of this simple risk quiz is required.
    No preview · Article · Aug 2015 · Sexually transmitted infections
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    ABSTRACT: The www.iwantthekit.org provides Internet-based, at-home sexually transmitted infection screening. The Web site implemented an automated test result access system. To evaluate potential deleterious effects of the new system, we analyzed demographics, Web site usage, and treatment. The post-Web site design captured more participant information and no decrease in requests, kit return, or treatment adherence.
    No preview · Article · May 2015 · Sexually transmitted diseases

  • No preview · Conference Paper · Jun 2014

  • No preview · Conference Paper · Jun 2014
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    ABSTRACT: Internet-based screening for vaginal sexually transmitted infections (STI) has been shown to reach high-risk populations. Published studies of internet-based screening for rectal STIs in women are needed. Our objectives were to describe the female users of a rectal internet-based screening intervention and assess what factors correlated with rectal positivity for STIs. The website http://www.iwantthekit.org offers free STI testing via home self-sampling kits. Women could order vaginal and rectal kits, both containing questionnaires. Rectal and vaginal swabs were tested for Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis using nucleic acid amplification tests. Data were analysed from 205 rectal kits from January 2009 through February 2011. Self-reported characteristics of participants were examined, and correlates of rectal STI positivity were analysed. Of the 205 rectal samples returned and eligible for testing, 38 (18.5%) were positive for at least one STI. The women were young (mean age 25.8 years), mostly African-American (50.0%), and only 14.0% always used condoms. After adjusting for age and race, Black race (AOR=3.06) and vaginal STI positivity (AOR=40.6) were significantly correlated with rectal STI positivity. Of women testing positive for rectal STIs who also submitted vaginal swabs, 29.4% were negative in the vaginal sample. Internet-based rectal screening can reach populations that appear to be at high risk for rectal STIs (18.5% prevalence) and led to the diagnosis of STIs in women who would not have been diagnosed vaginally. Black race and vaginal STI positivity were highly correlated with rectal STI positivity.
    No preview · Article · Mar 2014 · Sexually transmitted infections
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    ABSTRACT: Trichomonas vaginalis is the most prevalent non-viral sexually transmitted infection worldwide and improved diagnostics are critical to controlling this pathogen. Diagnostic assays that can be used in conjunction with routine chlamydia/gonorrhea nucleic acid-based screening are likely to have the most impact on disease control. Here we describe the performance of the new BD TVQ(x) amplified DNA Assay (TVQ) that can be performed on the automated BD Viper System. We focus on data from vaginal swab samples since this is the specimen type routinely used for traditional trichomonas testing and the recommended specimen type for chlamydia/gonorrhea screening. Vaginal swabs were obtained from women attending STD or family planning clinics at 7 sites. A patient collected vaginal swab was tested by TVQ; APTIMA TV (ATV) testing was performed using a clinician obtained vaginal swab. Additional clinician obtained vaginal swabs were used for wet mount and culture. Analyses included comparison against the patient infection status (PIS), defined by either a wet mount or culture positive result; head-to-head comparisons assessed by κ-scores; and latent class analysis (LCA) as an unbiased estimator of test accuracy. Data from 838 women, 116 of whom were infected with TV, were analyzed. TVQ sensitivity and specificity estimates based on the PIS were 98.3% and 99.0%, respectively. TVQ performed similarly to ATV (κ=0.938) in head-to-head analysis. LCA estimated TVQ sensitivity and specificity at 98.3 and 99.6%, respectively. The TVQ assay performed well using self-obtained vaginal swabs, the optimal sample type as recommended by the CDC for chlamydia/gonorrhea screening among women.
    Preview · Article · Jan 2014 · Journal of clinical microbiology
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    ABSTRACT: Abstract. Background: Clinicians and developers identify sensitivity as an important quality in a point-of-care test (POCT) for sexually transmissible infections (STIs). Little information exists regarding what patients want for STI POCTs. Methods: A qualitative study, encompassing five focus groups among attendees of STI and adolescent health centres in Baltimore, Maryland, and Cincinnati, Ohio, were conducted between March 2008 and April 2009. Discussion topics included advantages and disadvantages of having a POCT, perceived barriers to using POCTs in the clinic setting and at home, priorities for the development of new POCTs for STIs, and envisioned characteristics of an ideal POCT. All discussions were recorded and transcribed. A qualitative content analysis was performed to examine frequencies or patterns of recurring codes, which were regrouped and indexed to identify salient themes. Results: Patients attending STI and adolescent outpatient clinics are in favour of diagnostic tests that are rapid, easy to read and simple to use. Home testing options for POCTs were acceptable and provided better confidentiality, privacy and convenience, but clinic-based POCTs were also acceptable because they offer definitive results and ensure immediate treatment. Barriers to home POCTs centred on cost and the ability to read and perform the test correctly at home. Opinions did not differ by patient ethnicity, except that Hispanic participants questioned the reliability of home test results, wanted high sensitivity and desired bilingual instructions. Conclusions: Patients attending STI and adolescent medical centres are in favour of STI POCTs if they are affordable, rapid, easy to read and simple to use.
    Full-text · Article · Oct 2013 · Sexual Health
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    ABSTRACT: Professional organizations recommend rescreening chlamydia-infected women. The iwantthekit Internet-screening program offered rescreening opportunities by using iwantthekit. Mailed, home-collected vaginal swabs were tested for chlamydia, gonorrhea, and trichomonas by nucleic acid amplification tests. Demographics and risk behaviors of repeat users were determined from questionnaires. Predictors of repeat users were measured in a matched case-control study. Of 1747 women, 304 (17%), who used iwantthekit, indicated they had used the kit previously. Mean age was 24.7 ± 5.7 year and 69% were African American. Repeat iwantthekit users were more likely to be ≥20 years (OR = 2.10); were more likely to have been treated for a sexually transmitted infection (OR = 2.32); less likely to drink alcohol before sex (OR = 0.63); and to never use condoms (OR = 0.43). Of repeaters, 84.2% had a negative prior test and 15.8% had a positive. At current test, 13.2% were infected. Previous trichomonas was associated with current trichomonas (p < 0.05). The iwantthekit may offer rescreening opportunities for previously infected women.
    Full-text · Article · Jul 2013 · International Journal of STD & AIDS

  • No preview · Article · Jul 2013 · Sexually Transmitted Infections
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    B. Simons · C. Jessen · L. Rea · M. Barnes · P. Barnes · C. Gaydos
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    ABSTRACT: Background Alaska has one of the highest rates of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) in the United States. Alaska Native people, women and youth (ages 15–29) are disproportionately affected. Alaska Native health organisations have jurisdictions over large geographic areas, containing small isolated communities where a perceived lack of confidentiality and privacy is an identified barrier to accessing Sexually Transmitted Disease (STD) testing. The Alaska Native Tribal Health Consortium (ANTHC) has partnered with the “ I Want the Kit” programme (IWTK) at Johns Hopkins University (JHU) to provide a discrete and reliable STD testing alternative. Methods Alaska residents 14 years of age and older can request a no-cost STD testing kit online or by phone, which is mailed via U.S. Postal Service. After collection, the kit is returned in a prepaid envelope to JHU where it is tested for Chlamydia, gonorrhoea and Trichomonas . JHU reports all testing results to ANTHC, where a nurse notifies all participants of their results and refers positive cases for treatment. IWTK Alaska focuses its advertising efforts in rural Alaskan areas where the disease burden can be high and the barriers to accessing confidential healthcare are greatest. Results In 2012, JHU received a total of 439 home testing kit requests from Alaska of which 161 (37%) were returned. Alaska Native and/or American Indian participants comprised 30% and Whites 53% of kits tested; other minority groups made up the remaining 17% of kits tested. The ages of individuals who returned kits ranged from 16 to 63 years, with a median age of 28 years. Among the 161 kits tested, 14 (8.6%) tested positive for Chlamydia, two of these also tested positive for gonorrhoea, and four kits were positive for Trichomonas. Conclusion This web-based STD testing option increases access to STD testing by alleviating privacy and confidentiality concerns.
    Preview · Article · Jul 2013 · Sexually Transmitted Infections

  • No preview · Article · Jul 2013 · Sexually Transmitted Infections

  • No preview · Article · Jul 2013 · Sexually Transmitted Infections
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    ABSTRACT: Tests for Chlamydia trachomatis and Neisseria gonorrhoeae, which can provide results rapidly to guide therapeutic decision-making, offer patient care advantages over laboratory-based tests that require several days to provide results. We compared results from the Cepheid GeneXpert CT/NG (Xpert) assay to results from two currently approved nucleic acid amplification assays in 1,722 female and 1,387 male volunteers. Results for chlamydia in females demonstrated sensitivities for endocervical, vaginal, and urine samples of 97.4%, 98.7%, and 97.6%, respectively, and for urine samples from males, a sensitivity of 97.5%, with all specificity estimates being ≥99.4%. Results for gonorrhea in females demonstrated sensitivities for endocervical, vaginal, and urine samples of 100.0%, 100.0%, and 95.6%, respectively, and for urine samples from males, a sensitivity of 98.0%, with all estimates of specificity being ≥99.8%. These results indicate that this short-turnaround-time test can be used to accurately test patients and to possibly do so at the site of care, thus potentially improving chlamydia and gonorrhea control efforts.
    Full-text · Article · Mar 2013 · Journal of clinical microbiology
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    ABSTRACT: Background: Submission of self-collected penile samples collected at home could remove barriers that men face in getting tested for sexually transmitted infections (STIs). Methods: From December 2006 to July 2012, sexually active men aged ≥14 years were recruited by an educational internet program (http://www.iwantthekit.org) which offered free testing for Trichomonas vaginalis infection. Kits were ordered online and swabs were sent via US mail to the laboratory and tested by nucleic acid amplification tests. Demographics and sexual risk factors were accessed by questionnaires. Men called or were contacted to receive their results. Risk factors for trichomonas infection were determined by multivariate logistic regression Results: Of 4398 men requesting kits, 1699 (38.6%) returned swabs by mail (55.4% returned in 2012). Forty-one percent of men were aged <25 years, 43% were black subjects and 45% were white. The overall prevalence for trichomonas in the 1699 men was 3.7%; the highest prevalence by age group was for men aged 40-49 years (5.2%) and, by year, 216 men screened in 2008 had the highest prevalence (12.5%). Risk factors for 919 men whose risk information was collected by questionnaire (prevalence 6.0%) indicated that 9.6% had a concurrent chlamydia infection. Significantly associated risks factors included: black race (adjusted OR 2.67), residence in Illinois (OR 12.02), age 30-39 years (OR 6.63) and age >40 years (OR 5.31). Conclusions: A fairly high prevalence of trichomonas and sexual risk factors were demonstrated from internet recruitment of men. This method of engaging men to get screened for trichomonas may augment screening in STI clinics.
    Full-text · Article · Jan 2013 · Sexually transmitted infections
  • B. Simons · C. Jessen · L. Rea · M. Barnes · P. Barnes · C. Gaydos

    No preview · Article · Jan 2013 · International journal of circumpolar health
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    ABSTRACT: Background Self-obtained penile-meatal swabs and urine specimens have been used for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) for outreach screening in men. Objective To compare the sensitivity of self-collected male penile-meatal swabs and urine for the detection of CT, NG and TV. Methods Matching penile-meatal swabs and urines were collected at home after recruitment to the study; via the internet programme, http://www.iwantthekit.org. The instructions directed the participant to place the tip of a Copan flocked swab at the meatal opening of the urethra to collect the penile-meatal sample. Two ml of urine was collected after the swab onto a Copan sponge-on-a-shaft collection device. Both swab and urine were placed into individual Aptima transport media tubes and mailed to the laboratory for testing. All specimens were tested for CT and NG using the GenProbe Aptima Combo2 Assay and for TV using GenProbe Aptima Analyte Specific Reagents with TV oligonucleotides. Results Of 634 men, 86 (13.6%) were positive for CT, 9 (1.4%) were positive for NG and 56 (9.3%) positive for TV. For CT, swab sensitivity was 81/86 (94.2%), and urine sensitivity was 66/86 (76.7%). For NG, swab sensitivity was 9/9 (100%) and urine sensitivity was 8/9 (88.9%). For TV, swab sensitivity was 45/56 (80.4%) and urine sensitivity was 22/56 (39.3%). Conclusions Self-obtained penile-meatal swabs provided for the detection of more CT, NG and TV, than urine specimens.
    Full-text · Article · Oct 2012 · Sexually transmitted infections
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    ABSTRACT: Objectives: To compare the effectiveness and cost-effectiveness of a promising new point-of-care (POC) chlamydia test with traditional nucleic acid amplification testing (NAAT), and to determine the characteristics that would make a POC test most cost-effective. Methods: A decision tree was constructed to model chlamydia screening visits to a sexually transmitted disease clinic by a hypothetical cohort of 10,000 women. The model incorporated programmatic screening costs, treatment costs and medical costs averted through prevention of pelvic inflammatory disease (PID) and its sequelae. Parameter values and costs were estimated for each node in the decision tree based on primary data, published data and unpublished health data. Results: For the base-case scenario (POC sensitivity 92.9%; 47.5% of women willing to wait 40 min for test results; test cost $33.48), POC was estimated to save US$5050 for each case of PID averted compared with NAAT. One-way sensitivity analyses indicated that POC would dominate NAAT if the POC test cost is <US$41.52 or if POC sensitivity is ≥ 87.1%. In a probabilistic sensitivity analysis (Monte Carlo simulations, 10 000 iterations), 10.8% of iterations indicated that the POC strategy dominated the NAAT strategy. The mean incremental cost-effectiveness ratio indicated that the POC strategy would save US$28 in total, and avert 14 PID cases. Conclusions: A promising new chlamydia POC test is likely to be cost-effective compared with traditional NAAT. The POC test sensitivity, cost and proportion of women willing to wait for the POC test result are key elements to determining the cost-effectiveness of any new POC test strategy.
    Full-text · Article · Sep 2012 · Sexually transmitted infections

  • No preview · Article · May 2012 · Sexually Transmitted Infections
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    ABSTRACT: Dry-shipped and mailed vaginal swabs collected at home have been used in research studies for the detection of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (GC), and Trichomonas vaginalis (TV) by nucleic acid amplification tests (NAATs) in screening programs. A verification study was performed to compare the limit of detection of CT, GC, and TV on swabs that were dry-shipped to paired swabs that were wet-shipped in transport media through the US mail. The Centers for Disease Control and Prevention prepared inocula in sterile water to mock simulated urogenital swabs with high to low concentrations of CT and GC. Replicate swabs were inoculated with 100 μL of dilutions and were dry transported or placed into commercial transport media ("wet") for mailing for NAAT testing. The University of Alabama prepared replicate concentrations of TV, which were similarly shipped and tested by NAAT. All paired dry and wet swabs were detectable for CT. For GC, all paired dry and wet swabs were detectable for GC at concentrations ≥ 10(3). At 10(2) and 10 CFU/mL, the 10 replicate GC results were variably positive. For TV, wet and dry shipped concentrations >10(2) TV/mL tested positive, while results at 10 TV/mL were negative for dry swabs. Holding replicate dry swabs at 55 (○)C 5 days before testing did not affect results. NAATs were able to detect CT, GC, and TV on dry transported swabs. Using NAATs for testing home-collected, urogenital swabs mailed in a dry state to a laboratory may be useful for outreach screening programs.
    Full-text · Article · May 2012 · Diagnostic microbiology and infectious disease
  • y Jett-Goheen · Mathilda Barnes · Nicole Quinn
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    ABSTRACT: Background: Internet recruitment for self-collected urogenital samples at home for chlamydia testing has been used previously. We hypothesized that the use of social marketing techniques would increase numbers of persons screened in this program. Objectives: To increase the number of Internet recruited women and men ages 15-25 years who are screened for chlamydia in Maryland and DC during the GYT campaign for the month of April 2011 (CDC’s STD Awareness Month), and the following months. Methods: We incorporated multiple methods of social marketing: a QR barcode, to provide smart-phone-friendly access to the www.iwantthekit.org (IWTK) order page for the kit; text messaging for ordering kits; advertising on Facebook and “OkCupid”, a teen dating website; advertising in high schools, colleges, and STD clinics; radio advertisements; and online and print ads in free daily/weekly newspapers, which preview weekend events in Baltimore and Maryland. We monitored kit requests, kit returns, and website hits. Results: Kit requests went from a low of 101 ordered in January to a high of 669 ordered in April. Kits returned for testing went from a low of 54 in January to an average of 177/month in the months following social marketing (April-120, May-205, June-206). Website hits went from a low of 89,771 in January to a high of 184,556 in April. Positivity did not appear to increase, but total numbers of positives did increase due to more persons being tested. Conclusions: The successful use of social marketing techniques appeared to increase testing via Internet recruitment as website hits, kits requests, and kits returned for testing all increased during the period of the GYT campaign. Implications for Programs, Policy, and Research: Social marketing reaches targeted audiences and can increase chlamydia (and other STD) awareness and screening services. More study is required to independently assess the most cost-effective methods to increase screening for chlamydia
    No preview · Conference Paper · Mar 2012