Mathilda Barnes

Johns Hopkins Medicine, Baltimore, Maryland, United States

Are you Mathilda Barnes?

Claim your profile

Publications (40)92.49 Total impact

  • [Show abstract] [Hide abstract]
    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.
    Sexually transmitted diseases 05/2015; 42(5):243-245. DOI:10.1097/OLQ.0000000000000270 · 2.75 Impact Factor
  • [Show abstract] [Hide abstract]
    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.
    Sexually transmitted infections 03/2014; 90(6). DOI:10.1136/sextrans-2013-051167 · 3.08 Impact Factor
  • [Show abstract] [Hide abstract]
    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.
    Journal of clinical microbiology 01/2014; 52(3). DOI:10.1128/JCM.02966-13 · 4.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    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.
    Sexual Health 10/2013; 10(6). DOI:10.1071/SH13047 · 1.58 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    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.
    International Journal of STD & AIDS 07/2013; 24(9). DOI:10.1177/0956462413483252 · 1.04 Impact Factor
  • Sexually Transmitted Infections 07/2013; 89(Suppl 1):A32-A32. DOI:10.1136/sextrans-2013-051184.0100 · 3.08 Impact Factor
  • Sexually Transmitted Infections 07/2013; 89(Suppl 1):A354-A354. DOI:10.1136/sextrans-2013-051184.1106 · 3.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Tests for Chlamydia trachomatis and Neisseria gonorrhoeae, that 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 demonstrated sensitivities for endocervical, vaginal, and urine samples of 97.4%, 98.7%, and 97.6%, respectively, in females and in male urine a sensitivity of 97.5%, with all specificity estimates ≥99.4%. Results for gonorrhea demonstrated sensitivities for endocervical, vaginal, and urine samples of 100.0%, 100.0%, and 95.6%, respectively, in females, and in male urine a sensitivity of 98.0%, with all estimates of specificity ≥99.8%. These results indicate that this short-turn-around-time test can be used to accurately test patients, possibly at the site of care, thus potentially improving chlamydia and gonorrhea control efforts.
    Journal of clinical microbiology 03/2013; 51(6). DOI:10.1128/JCM.03461-12 · 4.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    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.
    Sexually transmitted infections 01/2013; 89(6). DOI:10.1136/sextrans-2012-050946 · 3.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    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.
    Sexually transmitted infections 10/2012; 89(4). DOI:10.1136/sextrans-2012-050686 · 3.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    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.
    Sexually transmitted infections 09/2012; 89(2). DOI:10.1136/sextrans-2011-050355 · 3.08 Impact Factor
  • Sexually Transmitted Infections 05/2012; 88(Suppl 1):A26-A26. DOI:10.1136/sextrans-2012-050601c.48 · 3.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    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.
    Diagnostic microbiology and infectious disease 05/2012; 73(1):16-20. DOI:10.1016/j.diagmicrobio.2012.02.008 · 2.57 Impact Factor
  • y Jett-Goheen, Mathilda Barnes, Nicole Quinn
    [Show abstract] [Hide abstract]
    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
    National STD Prevention Conference 2012 Centers for Disease Control and Prevention; 03/2012
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chlamydia trachomatis (CT) rates and incidence continue to increase, and university students are known to engage in high-risk activities, but studies of CT prevalence in this population are limited by poor screening rates. Utilisation of self-obtained sample (SoS) kits in private student residencies may reduce screening barriers. The authors sought to determine the relative effectiveness, and comparative effectiveness, of two SoS kit distribution mechanisms: one which provided kits directly to students and another encouraging students to order kits from a website. During 2010-2011, residents of six university dormitories were provided training sessions describing CT, the project and SoS kit use. Students in three dormitories were provided kits, and the remaining students directed to the website (http://www.iwantthekit.org). Of 391 resident students, 163 were provided with kits and 175 were directed to the website. Of provided kits, 12 (8 women) were returned and 2 (16.7%; both women) were positive. Of only three internet-requested kits, all were returned (all women) and none were positive. In a post-project survey examining non-participation, 26.2% of students were unaware of the project (no difference by dormitory or gender) and 58.5% of women cited prior testing as part of a medical exam. Though direct kit distribution was more effective in student screening engagement, overall participation was poor despite widespread advertising. The methodology of online testing and SoS kits has been well validated elsewhere, but research is needed to successfully engage university students in screening and refine SoS target populations in light of changing healthcare policies.
    Sexually transmitted infections 03/2012; 88(5):363-7. DOI:10.1136/sextrans-2011-050379 · 3.08 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background Chlamydia (CT) rates and incidence continue to increase, with adolescents/young adults at greatest risk. While university students are known to engage in high risk activities, CT prevalence studies are limited by poor screening rates. Free, self-obtained sample (SoS) kits, used in private student residencies, may reduce screening barriers. Objective Determine which SoS kit distribution mechanism was more effective in screening engagement: direct provision of kits to students, or encouraging students to order their kit from a website. Methods During 2010-2011, residents of six university dormitories were provided training sessions describing CT, the project, and SoS kit use. Students in three dormitories were provided kits, and the remaining students directed to the website (www.iwantthekit.org). Results Of 391 resident students, 163 were provided with kits and 175 were directed to the website. Of provided kits, 12 (8 female) were returned and 2 (16.7%; both female) were positive. All three internet-requested kits were returned (all female) and none were positive. In a post-project survey examining nonparticipation, 26.2% of students were unaware of the project (no difference by dormitory or gender; p>0.05), and 58.5% of females cited prior testing as part of a medical exam. Conclusions Direct distribution of kits was more effective in student screening engagement, but would cost more due to non-used kits. While total student engagement was <4%, the positivity rate of 16.7% (2/12) indicates a degree of self selection. The data indicated that SoS kits may effectively complement screening programs in the university setting.
    139st APHA Annual Meeting and Exposition 2011; 11/2011
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although the Centers for Disease Control and Prevention have recommended population-wide Chlamydia trachomatis screening of sexually active women less than 26 years of age, more than half of sexually active young women are not routinely screened. A Website (IWTK, www.iwantthekit.org), was developed in 2004 to promote home-based sample collection. A decision tree was designed to model a hypothetical cohort of 10,000 women per year who order an internet-based C. trachomatis screening kit. We compared the incremental cost-effectiveness of 2 screening strategies: self-sampling via the IWTK website, and traditional, clinic-based screening by the same cohort of women who used IWTK. Probabilities and costs were estimated for each node in the decision tree. Estimates were derived from primary data, published data, and unpublished health data. The internet-based screening strategy prevented 35.5 more cases of pelvic inflammatory disease and saved an additional $41,000 in direct medical costs as compared with the clinic-based screening strategy. Our model estimates demonstrated that an internet-based, self-swab screening strategy was cost-effective compared with the traditional, clinic-based screening strategy. Assuming that the popularity of the use of the internet as a resource for information about healthcare and sexually transmitted infections leads to an increased use of IWTK, the public health benefit of this cost-effective strategy will be even greater.
    Sexually transmitted diseases 09/2011; 38(9):815-20. DOI:10.1097/OLQ.0b013e31821b0f50 · 2.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Submission of self-obtained vaginal samples (SOVs) collected at home could remove barriers that women face in getting tested for sexually transmitted infections (STIs). Internet recruitment of SOVs is highly acceptable. Sexually active women ≥14 years were recruited by an educational Internet program, available at: www.iwantthekit.org (IWTK), which offered free testing for trichomonas as part of a panel, which also offered testing for chlamydia and gonorrhea. Kits were ordered online, SOVs were sent through US mail to the laboratory, and tested by nucleic acid amplification tests. Demographics and sexual risk factors were accessed by questionnaires. Women called or were contacted to receive their results. Of women requesting kits, 1525 (43%) returned swabs by mail. In all, 61% were <25 years, 52% were black, and 80% were single. Vaginal discharge was reported by 44%, prevalence for trichomonas was 10% (10% for chlamydia, 1% for gonorrhea), and 18% had at least one prevalent STI. Multivariate logistic regression demonstrated several significantly associated risks factors as follows: adjusted odds ratio for black race was 2.69; for residence of Illinois, 3.85; for not having health insurance, 1.57; for lack of a bachelor's degree, 5.53; for having 2 to 15 partners, 1.60; for having ≥16 partners in previous year, 3.51; for being bisexual, 2.0; for not always using condoms, 3.04; and for having a partner who had a previous STI, 1.71. Age was not associated with trichomonas infection. All infected women were treated. A high prevalence of trichomonas and high sexual risk factors were demonstrated. Internet recruitment was a useful method of screening women for trichomonas infection.
    Sexually transmitted diseases 09/2011; 38(9):828-32. DOI:10.1097/OLQ.0b013e3182228911 · 2.75 Impact Factor
  • Sexually Transmitted Infections 07/2011; 87(Suppl 1):A38-A39. DOI:10.1136/sextrans-2011-050109.38 · 3.08 Impact Factor
  • Sexually Transmitted Infections 07/2011; 87(Suppl 1):A297-A297. DOI:10.1136/sextrans-2011-050108.478 · 3.08 Impact Factor

Publication Stats

376 Citations
92.49 Total Impact Points

Institutions

  • 2013
    • Johns Hopkins Medicine
      • Division of Infectious Diseases
      Baltimore, Maryland, United States
  • 2006–2013
    • Johns Hopkins University
      • • Division of Infectious Diseases
      • • Department of Population, Family and Reproductive Health
      • • Department of Medicine
      Baltimore, Maryland, United States
  • 2012
    • Southern Illinois University School of Medicine
      • Department of Family and Community Medicine
      Springfield, IL, United States
  • 2010
    • Johns Hopkins Bloomberg School of Public Health
      • Department of Epidemiology
      Baltimore, Maryland, United States
  • 2008
    • University of Massachusetts Medical School
      • Department of Pediatrics
      Worcester, MA, United States