Background:: Increasing availability of urine testing for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) offers expanded opportunities to collaborate with community‐based organizations (CBOs) to screen high‐risk populations for sexually transmitted diseases (STDs).
Goal:: To determine the prevalence and correlates of genital tract gonococcal and chlamydial infection among CBO clients, and to assess the feasibility of implementing widespread community‐based STD screening programs.
Design:: Free, voluntary, confidential first‐catch urine screening was conducted at 20 CBOs serving disadvantaged populations in St. Louis, MO. Brief demographic, behavioral, and sexual contact data were obtained from all participants. Urine samples were tested by ligase chain reaction (LCR). Persons testing positive were promptly notified and directed to seek treatment.
Results:: A GC and/or CT infection was identified in 24 of 277 persons (8.7%) screened; 2 persons were infected with GC only, 17 with CT only, and 5 with GC and CT. Treatment was documented for 22 persons (91.7%) testing positive. The highest rates of infection were found at shelters (12.3%) and residence facilities (11.1%). Costs of screening were $38 per sample collected and $453 per case identified.
Conclusion:: Community‐based urine testing successfully identified GC and CT infections, and was well accepted by community members and CBOs. Community‐based screening can significantly impact STD epidemiology by facilitating early detection, treatment, and interruption of transmission.
*From the Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri; the †City of St. Louis Department of Health and Hospitals, St. Louis, Missouri; and the ‡Section of STD/HIV/AIDS Prevention and AIDS Care, Missouri Department of Health, Jefferson City, Missouri
The authors thank Diane Granberry‐Owens, who coordinated and led the screening programs; Rachel Addison‐Hardy, Tara Robinson, Mark King, Denise Johnson, Bill Lafser, Charlene Teaser‐Polk, Nat Munro, Denise Henry, and Cathy Liang, who conducted the screenings; Dr. Ella M. Swierkosz and technicians at the Saint Louis University Hospital, Microbiology Laboratory, where the LCR assays were performed; the three HIV/AIDS programs that facilitated entry into numerous CBOs; and Beth Meyerson for facilitating a partnership between the Missouri Department of Health and the screening project.
Supported in part by cooperative agreement R30/CCR713576; the Centers for Disease Control and Prevention, Division of STD Prevention and Division of HIV/AIDS Prevention, Atlanta, GA; and the National Institute of Mental Health, Washington, DC.
Reprint requests and correspondence: Bradley Stoner, MD, PhD, Division of Infectious Diseases, Washington University School of Medicine, 660 S. Euclid Avenue, Box 8051, St. Louis, MO 63110. E‐mail: firstname.lastname@example.org
Received for publication June 29, 1999, revised August 20, 1999, and accepted August 26, 1999.
CHLAMYDIA TRACHOMATIS AND Neisseria gonorrhoeae are the two most commonly reported sexually transmitted diseases (STDs) in the United States.1 Serious long‐term consequences of untreated gonococcal and chlamydial infection include pelvic inflammatory disease (PID), ectopic pregnancy, tuboovarian abscess, and infertility.2 In addition, inflammatory bacterial STDs have been shown to increase the risk of HIV acquisition and the amount of HIV viral shedding in genital tract secretions.3–5 Many gonococcal and chlamydial infections are asymptomatic in males and females, and may be most effectively detected through screening programs involving high‐risk populations.6–11
Urine‐based testing for gonorrhea and chlamydia by ligase chain reaction (LCR) is sensitive and specific.12–15 The availability of urine‐based testing is revolutionizing the delivery of STD services by allowing noninvasive, portable screening of persons who are difficult to reach because of limited healthcare access or an asymptomatic infection that does not trigger healthcare‐seeking responses. Urine testing has proven feasible and effective in the diagnosis of asymptomatic chlamydial and gonococcal infections in a variety of clinical settings.14,16–19 In addition, the portability of the new technologies has been tested in street outreach programs involving a variety of community‐based facilities to access populations at risk.20–22 Given the public recognition of need for innovative STD‐care delivery systems and mechanisms,23,24 more information is needed to better understand the role that partnerships with community‐based organizations (CBOs) could play in STD and HIV education and services.
St. Louis, MO is a community with high STD morbidity, ranking third among US cities in 1997 for per capita rates of infection with N gonorrhoeae (GC) (825 per 100,000 inhabitants) and C trachomatis (CT) (755 per 100,000 inhabitants).1 Despite the general decline in national and local prevalence in recent years, 1998 data from St. Louis demonstrate a 30% increase in GC infection and a 10% increase in CT infection during the past year.25 Five contiguous zip codes in the city's northern area accounted for over 43% of the city's gonorrhea case burden and 27% of the chlamydia cases in 1997.26 We undertook this 10‐month study from October 1997 to July 1998 to assess the prevalence and predictors of infection for gonorrhea and chlamydia at community settings in a high‐morbidity area. In this study, a CBO was viewed from an access vantage point; in addition to using institutional settings such as drug treatment centers and shelters to reach persons at risk, facilities such as bars and stores were considered CBOs by enabling access to populations at risk for STDs in “user‐friendly” neighborhood settings. The need for partnerships between healthcare delivery and community organizations has been recognized to be essential when an STD is widely distributed throughout a community.24
The study was conducted as a site‐specific activity of the St. Louis Gonococcal Community Action Project (GCAP), a multisite collaborative research program funded by the Centers for Disease Control and Prevention (CDC) and the National Institute of Mental Health (NIH). Formative research with STD patients, community members, and directors of CBOs serving residents in the high‐morbidity area suggested that screening should be coupled with educational presentations by project members. To implement the screening, staff contacted CBOs with whom relationships were already established, collaborated with STD and HIV outreach workers at the city health department who were already conducting risk‐reduction programs at CBOs, and collaborated with three community‐based AIDS advocacy and prevention organizations.
Screening was offered at a variety of community‐based sites, including shelters, residence facilities, bars, drug‐treatment centers, soup kitchens, and other outreach sites. Shelters provided temporary housing for 30 days or less; drug treatment facilities were either outpatient centers or had inpatient stays of 30 days to 90 days; and residence facilities were longer‐term (≥ 6 months) housing centers primarily serving women and children. A flexible format was developed to accommodate varied CBO institutional and programmatic requirements. At some sites, the screening complemented an educational presentation provided by the health department or AIDS group; at some sites, screening staff presented an educational presentation of a 20‐minute slide show addressing gonorrhea, chlamydia, and pelvic inflammatory disease (PID), followed by the offer to screen; and at other sites, a table was set up and passers‐by were recruited. Brochures and condoms were available in all settings. Screenings were conducted by project staff and city and state disease‐intervention specialists.
At each site, attendees 15 years and older were invited to participate. In some cases, persons younger than 15 years were screened if they attended a screening event and requested to be included in the study. Later in the project period, screening was restricted to persons age 15 years to 30 years to maximize the likelihood of detecting prevalent disease in adolescents and young adults. Persons older than 30 years attending these events were offered two free bus passes to the city STD clinic, where free screening would be performed. In all cases, urine testing was offered to persons who repeatedly requested inclusion in the project.
Testing at all sites was free, voluntary, and confidential. Participants completed a brief questionnaire to elicit demographic data, contact information, symptom status (for discharge and dysuria), sexual history, and written consent for their urine testing. To facilitate healthcare seeking, participants were asked during initial consent acquisition for written permission to fax positive results to their doctor or clinic. Younger persons were asked for the name and telephone number of a trusted adult with whom positive results could be shared. Participants were given a card with their unique screening number and a phone number to call for results in 1 week. Each participant was given a 30‐ml urine specimen container and was instructed to give 15 ml to 20 ml of first‐catch urine. Specimens were stored in an ice cooler and transported to the lab after the screening event. The LCR assays (Abbott LCx; Abbott Diagnostics, Abbott Park, IL) for CT and GC were run in batches performed twice weekly.
Once results were available, screening staff immediately notified persons whose test results were positive and reported locating information to the health department. Every effort was made to facilitate healthcare seeking and to verify provision of appropriate antibacterial medication. Health department staff assisted in contacting untreated index cases, and routine partner notification was undertaken for gonorrhea contacts in accordance with current health department guidelines. While formal contact tracing was not performed for chlamydia contacts, persons testing positive were counseled to notify their sex partners and refer them for evaluation and treatment.
Persons testing positive for GC or CT were treated with standard antibiotic regimens as recommended by the CDC.27 Those with CT infection received 1‐g azithromycin (single oral dose), 100‐mg doxycycline (orally, twice daily for 1 week), or 500‐mg erythromycin (orally, four times daily for 1 week). Persons with GC received 125‐mg ceftriaxone (single intramuscular injection), 400‐mg cefixime (single oral dose), 400‐mg ofloxacin (single oral dose), or 500‐mg ciprofloxacin (single oral dose). Persons with both GC and CT infections were treated with regimens effective against both organisms. Study data were analyzed using standard statistical software (EpiInfo, CDC, Atlanta, GA). All procedures were approved in advance by the Institutional Review Board of the Washington University Human Studies Committee.
A total of 277 persons were screened at 31 separate screening events at 20 community‐based sites in St. Louis. Demographic, medical history, and sociobehavioral characteristics of study participants are provided in Table 1. The majority of participants who elected screening were female (59.2%), African American (94.2%), and asymptomatic for genitourinary complaints at the time of screening (92.7%), with a mean age of 28.4 years (range 13 to 57 years). Half of all persons who elected screening reported a history of previous STDs, with gonorrhea and chlamydia being the most commonly reported prior infection. The mean number of sex partners in the past 3 months for all persons enrolled was 2.0, and 69.5% of the study sample did not use a condom during their most recent intercourse. Eleven women (9.1%) self‐reported pregnancy at the time of screening. Screenings lasted 1.5 hours to 2 hours, and included a formal presentation, specimen collection, and delivery to the laboratory. An average of nine specimens were collected from each event. One or two project workers attended each event, spending an average of 3.2 person‐hours per screening session.
Among all participants enrolled, younger persons (age 15‐25 years) were more likely to have used condoms during last intercourse (42.5% versus 20.5%, P < 0.001) and less likely to have had a history of previous STDs (40.5% versus 57.4%, P = 0.01) than persons age 26 and older. Males reported more partners in the past 3 months than females (3.1 versus 1.3, P ≤= 0.003), independent of age.
Seventeen females and seven males tested positive for gonococcal and/or chlamydial infection, for a cohort positivity rate of 8.7% (Table 2). Chlamydial infection alone occurred in 17 persons, GC infection alone was found in two persons, and GC and CT coinfection occurred in five persons. Gonococcal prevalence was 2.5% and chlamydial prevalence was 7.9% among all persons screened. Interestingly, 71.4% of all persons with gonorrhea were also coinfected with chlamydia, whereas only 22.7% of persons with CT infection were coinfected with GC.
Sociodemographic and Behavioral Correlates of Infection
Demographic, medical history, and behavioral variables were analyzed to determine the degree of association with infection status (Table 3). Younger age (P = 0.03) and pregnancy at the time of screening (P = 0.02) correlated significantly with infection with N gonorrhoeae or C trachomatis. Likelihood of infection did not correlate with gender, race or ethnicity, symptom status at the time of screening, previous STD history, condom use at last intercourse, or number of sex partners in the past 3 months. Findings did not change when analyses were controlled for age, race or ethnicity, and gender of study participants.
Subanalyses of 66 younger females (age 24 years and younger) revealed that 13.6% were infected with CT, and 4.5% had GC infection (data not shown). These rates are comparable to those obtained by a sample of STD, teenage, and community‐health clinics serving high‐morbidity neighborhoods in St. Louis, based on 1997 data from the Missouri Infertility Prevention Project.25
Testing and Treatment Issues
Project protocol provided for timely treatment by referral to public STD clinics or to a competent medical provider, and aggressive follow‐up evaluation was sought for all persons testing positive. Overall, appropriate antibiotic treatment was documented for 22 of 24 persons testing positive (91.7%), of which 17 persons (77.3%) sought treatment at an STD clinic and 5 persons (22.7%) sought treatment from a private medical provider. Median time from screening to treatment was 17.5 days.
Test positivity rates were calculated by community site of recruitment and study enrollment (Table 4). Shelters had the highest prevalence of infection among all persons screened (12.3%) and comprised 26.4% of the entire study sample. High prevalence of gonococcal and chlamydial infection was also identified among persons tested at residence facilities (11.1%), a resale store (10.0%), youth programs (9.1%), and a soup kitchen (8.3%). Relatively few infections were identified among persons screened at drug‐treatment facilities (4.3%) and bars (4.8%), although these sites together constituted approximately one third of the entire study sample.
The noninvasive, community‐based screening project was effective in promoting early detection and prompt treatment among predominantly asymptomatic persons. Infection with N gonorrhoeae or C trachomatis was identified in 8.7% of all persons screened. Prevalence of infection was higher in particular subgroups; for example, 13.9% CT‐positive and 4.2% GC‐positive test results were obtained among females age 25 and younger. These rates compare favorably with findings of school‐based screening programs in other cities. Among female middle school students in Baltimore, chlamydia prevalence was 16.5% and gonococcal prevalence was 2.1%,16 whereas among junior and senior high school students in New Orleans, chlamydia prevalence was 6.5%.18 In Denver, chlamydial prevalence for male youth screened at facilities such as high schools and community centers was 4.4%, compared with 11.9% for those screened during outreach.21 In San Diego, chlamydia prevalence was 6.1% in outreach screening.20
Certain community‐based venues were more productive than others in providing program access to infected persons. The highest concentrations of infections were found at shelters and residence facilities (especially for women and children), probably reflecting the chaotic or transitional nature of their residents' lives. The low yield from the participating drug‐treatment centers and bars might be due to the older age of the population tested at these sites. Future screening programs may take these findings into account in fashioning directed screenings to shelters, residence facilities, and other high‐morbidity sites.
Ultimately, screening programs are only effective if infected persons are successfully notified and brought to treatment. Several studies, including this one, indicate that community‐based STD screening positively enhances health‐seeking behavior. This is particularly important in locales where field‐delivered treatment for STDs is not generally available or practiced. Without field‐treatment services, positive cases detected by screening must be notified and then seek care from a healthcare provider for therapy. Persons with asymptomatic infection may delay healthcare seeking or otherwise fail to obtain adequate treatment, despite notification efforts. For example, 26% of female STD clinic patients in Baltimore with positive CT test results did not return for therapy, despite aggressive attempts to notify them of positive results. Among those who did return, the median interval from testing to treatment was 14 days.14 In Birmingham, 20% of patients with untreated GC infection and 20% of patients with untreated CT infection failed to return to the STD clinic for treatment within 1 month of testing.28 Leenaars et al29 found that almost one fourth of individuals with STD‐related symptoms delayed seeking care over 1 month. High failure rates of return or delays in healthcare seeking serve to mitigate the value of screening programs.
A previous study of 200 gonorrhea patients in St. Louis revealed that 34 persons not treated at initial visit waited an average of 26.9 days before seeking treatment, and 12 persons (35%) had sex before treatment.26 In the present study, we identified 24 cases of gonococcal and/or chlamydial infection of which 22 (91.7%) were treated within a median of 17.5 days. During the study, the interval from testing to treatment was reduced as investigators implemented more effective ways to ensure treatment of persons testing positive (e.g., requesting written permission from participants to fax test results to physicians' offices). Other screening projects have also shown fairly rapid time to treatment or a high treatment rate; 97% of persons were treated in an average of 8 days with directly observed therapy in Denver,21 100% of persons were successfully administered treatment in San Diego,20 and 86% of persons were successfully treated at public schools in New Orleans.18 In retrospect, better tracking methods were needed, including a “code” word or message to use on the phone so that persons testing positive would recognize that project workers were calling with results. (One young man with chlamydia answered the phone, but then refused to speak to a project staff member or otherwise receive his test results.)
Screenings at CBOs offer several advantages. First, most CBOs appreciate being able to increase services offered to their clients without increasing their cost or time burdens, while having the flexibility to incorporate screenings into their individual routines. From the service providers' vantage point, several people may be reached during a single community‐based presentation. We collected an average of nine urine specimens from each event, with even more persons attending the educational presentations. Further, the stability offered by CBOs within the community may facilitate successful patient follow‐up evaluation by providing public health workers with venues and access points to reach persons who may otherwise be inaccessible for notification and treatment. Additional benefits include an increased sense of partnership between researchers, public health workers, and community gatekeepers; and community members' appreciation that access to health care was provided in a “user‐friendly” manner.
Finally, screening in CBOs may also be more cost efficient than street outreach. We calculated personnel and test costs of $38 per urine sample collected and $435 per positive case identified; however, these figures do not include costs associated with locating and treating persons testing positive for either infection. These costs compare favorably with cost estimates for CBO‐based CT screening in Denver of approximately $17 per urine specimen and $340 per positive case identified.30 In a Louisiana public school screening project, laboratory costs were estimated at $18 per test and $272 for each positive case identified, excluding staff time to collect specimens.18 In contrast, an outreach study of chlamydia in young men in San Diego estimated $103 for each test obtained and $1,677 for each positive test identified.20 Thus, incorporating urine‐based screening into ongoing educational efforts at CBOs can be an effective and cost‐efficient way to reach members of communities at risk and to build partnerships with community stakeholders for STD reduction.
The direct costs of any screening program must also be balanced against savings due to averted morbidity. Recent estimates suggest that up to 15% of women with untreated, persistent cervical chlamydial infection may develop symptomatic pelvic inflammatory disease (PID); 17% of these women are likely to develop infertility, 8% are likely to have an ectopic pregnancy, and 12% experience chronic pelvic pain.31,32 Complications in males may include epididymitis and infertility. Many of the persons screened in this program would have been unlikely to access STD services at other clinical sites; therefore, detection of infections in 17 females through screening may have averted at least two cases of PID and associated complications. More widespread use of screening can be expected to increase commensurately the degree of long‐term morbidity averted in at‐risk populations.
Community‐based urine screening for genital tract infection with N gonorrhoeae and C trachomatis effectively identified prevalent infections in populations with limited healthcare access. Screening was well accepted by community‐based organizations and clients. Screening in high‐prevalence communities offers an extension of STD services beyond the traditional clinic walls, and allows for the development of meaningful collaborations between public health workers and community groups. Screening may be targeted toward younger cohorts to maximize likelihood of obtaining positive test results, but inclusion of older persons in screening programs can serve to secure “buy‐in” and positively influence participation by younger persons who seek their counsel in issues related to STD healthcare seeking.33 Through community‐based screening programs, CBOs can offer accurate, noninvasive health services to persons at risk for STD who otherwise may have limited access to, or low priority for, STD healthcare seeking. The partnership between healthcare providers and CBOs presents a “win‐win” option for improving STD healthcare delivery to youth and adults at risk.
1. Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance 1997. Atlanta: US Department of Health and Human Services, Public Health Service; September 1998.
2. Aral SO, Wasserheit JN. Social and behavioral correlates of pelvic inflammatory disease. Sex Transm Dis 1998; 25:378–385.
3. Cohen MS, Hoffman IF, Royce RA, et al. Reduction of concentration of HIV-1 in semen after treatment of urethritis: implications for prevention of sexual transmission of HIV-1. Lancet 1997; 349:1868–1873.
4. Laga M, Manoka A, Kivuvu M, et al. Non-ulcerative sexually transmitted diseases as risk factors for HIV-1 transmission in women: results from a cohort study. AIDS 1993; 7:95–102.
5. Moss GB, Overbaugh J, Welch M, et al. Human immunodeficiency virus DNA in urethral secretions in men: associations with gonococcal urethritis and CD4 depletion. J Infect Dis 1995; 172:1469–1474.
6. Cates W, Wasserheit JN. Genital chlamydia infections: epidemiology and reproductive sequelae. Am J Obstet Gynecol 1991; 164:1771–1781.
7. Centers for Disease Control and Prevention. Chlamydia trachomatis
genital infections-United States, 1995. MMWR 1997; 46:193–198.
8. Handsfield HH, Lipman TO, Harnisch JP, Tronca E, Holmes KK. Asymptomatic gonorrhea in men: diagnosis, natural course, prevalence and significance. N Engl J Med 1974; 290:117–123.
9. Hook EW, Handsfield HH. Gonococcal infections in the adult. In: Holmes KK, Mardh PA, Sparling PF, Lemon SM, Stamm WE, Piot P, Wasserheit JN, eds. Sexually Transmitted Diseases. 3rd ed. New York: McGraw-Hill, 1999:451–466.
10. Sherrad J, Barlow D. Gonorrhea in men: clinical and diagnostic aspects. Genitourin Med 1996; 72:422–426.
11. Stamm WE, Koutsky LA, Benedetti JK, Jourden JL, Brunham RC, Holmes KK. Chlamydia trachomatis
urethral infections in men: prevalence, risk factors, and clinical manifestations. Ann Intern Med 1984; 100:47–51.
12. Chernesky MA, Jang D, Lee H, et al. Diagnosis of Chlamydia trachomatis
infections in men and women by testing first-void urine by ligase chain reaction. J Clin Microbiol 1994; 32:2682–2685.
13. Crotchfelt KA, Welsh LE, Debonville D, Rosenstraus M, Quinn TC. Detection of Neisseria gonorrhoeae
and Chlamydia trachomatis
in genitourinary specimens from men and women by a coamplification PCR assay. J Clin Microbiol 1997; 35:1536–1540.
14. Hook EW, Spitters C, Reichart CA, Neumann TM, Quinn TC. Use of cell culture and a rapid diagnostic assay for Chlamydia trachomatis
screening. JAMA 1994; 272:867–870.
15. Smith KR, Ching S, Lee H, Ohhashi Y, Hu HY, Fisher HC, Hook EW. Evaluation of ligase chain reaction for use with urine for identification of Neisseria gonorrhoeae
in females attending a sexually transmitted disease clinic. J Clin Microbiol 1995; 33:455–457.
16. Burstein GR, Gaydos CA, Diener-West M, Howell MR, Zenilman JM, Quinn C. Incident Chlamydia trachomatis
infections among inner-city adolescent females. JAMA 1998; 289:521–526.
17. Burstein GR, Waterfield G, Joffe A, Zenilman JM, Quinn TC, Gaydos CA. Screening for gonorrhea and chlamydia by DNA amplification in adolescents attending middle school health centers. Sex Transm Dis 1998; 25:395–402.
18. Cohen DA, Nsuami M, Etame RB, et al. A school-based chlamydia control program using DNA amplification technology. Pediatrics 1998; 101:E1.
19. Gaydos CA, Crotchfelt KA, Howell MR, Kralian S, Hauptman P, Quinn TC. Molecular amplification assays to detect chlamydial infections in urine specimens from high school female students and to monitor the persistence of chlamydial DNA after therapy. J Infect Dis 1998; 177:417–424.
20. Gunn RA, Podschun GC, Fitzgerald S, Hovell MF, Farshy CE, Black CM, et al. Screening high-risk adolescent males for Chlamydia trachomatis
infection. Sex Transm Dis 1998; 25:49–52.
21. Rietmeijer CA, Yamaguchi KJ, Ortiz CG, et al. Feasibility and yield of screening urine for Chlamydia trachomatis
by polymerase chain reaction among high-risk male youth in field-based and other nonclinic settings. Sex Transm Dis 1997; 24:429–435.
22. Marrazzo JM, White CL, Krekeler B, Celum CL, Lafferty W, Stamm WE, Handsfield HH. Community-based urine screening for Chlamydia trachomatis
with a ligase chain reaction assay. Ann Intern Med 1997; 127:796–803.
23. Thomas RE, William TB, for the Institute of Medicine. The Hidden Epidemic. Washington, DC: National Academy Press, 1997.
24. Gunn RA, Rolfs RT, Greenspan JR, Seidman RL, Wasserheit JN. Special communication: the changing paradigm of sexually transmitted disease control in the era of managed health care. JAMA 1998; 279:680–684.
25. Missouri Department of Health. STD/HIV Surveillance 1997. Jefferson City, MO, Missouri Department of Health, 1998.
26. Jones CA, Stoner BP, Knaup R. Demographic and behavioral correlates of gonococcal infection in an urban area (abstract no. p306). Paper presented at: International Congress of Sexually Transmitted Diseases (ISSTDR). Seville, Spain, 1997.
27. Centers for Disease Control and Prevention. 1998 Guidelines for Treatment of Sexually Transmitted Diseases. MMWR 1998; 47(RR-1) 1–116.
28. Schwebke JR, Sadler R, Sutton JM, Hook EW. Positive screening tests for gonorrhea and chlamydial infection fail to lead consistently to treatment of patients attending a sexually transmitted disease clinic. Sex Transm Dis 1997; 24:181–184.
29. Leenaars PEM, Rombouts R, Kok G. Seeking medical care for a sexually transmitted disease: determinants of delay-behavior. Psychol Health 1993; 8:17–32.
30. Bull SS, Jones CA, Granberry-Owens D, Stoner BP, Rietmeijer CA. Acceptability and feasibility of urine screening for Chlamydia trachomatis
and Neisseria gonorrhoeae
in community organizations: perspectives from Denver, CO and St. Louis, MO. Am J Public Health 2000 (in press).
31. Genc M, Mardh P-A. A cost-effectiveness analysis of screening and treatment for Chlamydia trachomatis
infection in asymptomatic women. Ann Intern Med 1996; 224:1–7.
32. Magid D, Douglas JM Jr, Schwartz S. Doxycycline compared with azithromycin for treating women with genital Chlamydia trachomatis
infections: an incremental cost-effectiveness analysis. Ann Intern Med 1996; 124:389–399.
33. Fortenberry JD. Health care seeking behaviors related to sexually transmitted diseases among adolescents. Am J Public Health 1997; 87:417–420.