In her recent editorial, Judith Stephenson highlighted the lack of trial evidence supporting the opportunistic approach used by the National Chlamydia Screening Programme (NCSP) and calls for a randomised control trial (RCT) to compare opportunistic versus a register based call/recall
approach to screening1. What this editorial and the National Institute for Health and Clinical Evidence (NICE...
In her recent editorial, Judith Stephenson highlighted the lack of trial evidence supporting the opportunistic approach used by the National Chlamydia Screening Programme (NCSP) and calls for a randomised control trial (RCT) to compare opportunistic versus a register based call/recall
approach to screening1. What this editorial and the National Institute for Health and Clinical Evidence (NICE) commissioned rapid review, of which she is a co-author, inadequately highlight and therefore underplay, are the practical and ethical difficulties, time requirement and expense of undertaking such a trial2. Senok et al. undertook a pilot exercise addressing this and concluded that a definitive trial would be resource intensive and need to be of a substantial size3.
The NCSP uses a multifaceted opportunistic approach to screening which is intended to make a sustainable impact within the local health economy and is not restricted to health care settings. Those RCTs that have been undertaken in relation to chlamydia screening measured the success of achieving a single screen and were restricted to specific
settings, such as general practice, or a single method, such as postal invitation. This underestimates the potential benefit of the broader approach employed by the NCSP. The constraints of a RCT design would also restrict the ability of the programme to be a continuous public health
intervention incorporating new technology to promote accessibility and acceptability to young persons, such as screening requests via the Internet, and texting results.
We agree with Stephenson that good quality research into the natural history of chlamydial infection and related complications is to be encouraged. The evolution of the NCSP research and development agenda and associated performance indicators is well underway. This is integral to the development of the programme, as are more focussed investigations including RCTs in addressing ways of improving programme effectiveness and modernising sexual health services for young people.
We do not support the pursuit of the holy grail of RCT evidence in relation to the specific question of opportunistic versus register call/recall. Further debate here takes the focus away from addressing the
real problem in hand, that of the rising number of young persons with chlamydial infection and the associated risk of serious long term morbidity and potential infertility.
References
1 Stephenson J. NICE guidance and the National Chlamydia Screening Programme. Sex Transm Infect 2007;83:170.
2 National Institute for Health and Clinical Excellence. Revised rapid review of evidence for the effectiveness of screening for genital chlamydia infection in sexually active young women and men.
http://nice.org.uk/page.aspx?o=371768. Accessed 19 April 2007.
3 Senok A, Wilson P, Reid M, Scoular A, Craig N, McConnachie A, et al.. Can we evaluate population screening strategies in UK general practice? A pilot randomized controlled trial comparing postal and opportunistic screening for genital chlamydial infection. J Epidemiol
Community Health 2005;59:198-204.
In their manuscript, Utility of the Determine TP Rapid Syphilis Test in Commercial Sex Venues in Peru, Campos et al. report poor validity and utility of a point-of-care rapid syphilis assay in an outreach facility for commercial sex workers in urban Peru [1]. We have identified
potential limitations in their study design, which might have contributed to their conclusion that the TP Determine Rapid Syphilis Te...
In their manuscript, Utility of the Determine TP Rapid Syphilis Test in Commercial Sex Venues in Peru, Campos et al. report poor validity and utility of a point-of-care rapid syphilis assay in an outreach facility for commercial sex workers in urban Peru [1]. We have identified
potential limitations in their study design, which might have contributed to their conclusion that the TP Determine Rapid Syphilis Test (Abbott Laboratories, Tokyo, Japan) is not a suitable screening test.
One possible methodological shortcoming was the direct application of unheparanized whole blood onto the TP Determine testing device. In a combined laboratory and clinical study of the TP Determine test, we previously reported a poor sensitivity (11/17, 64.7%) with the rapid-test as compared to TP-PA using whole blood directly applied to the testing pad [2]. In response, we continued our study with the use of heparinized capillary tubes for collection of whole blood and deposition onto the testing pad. This alteration resulted in 100% sensitivity (52/52) of the TP Determine for the remaining specimens. The authors here report an almost identical sensitivity of 64% when comparing directly applied whole blood to TP Determine tests compared to rapid plasmin reagin (RPR) confirmed with treponema pallidum particle agglutination (TPHA). When the
authors repeated the use of rapid tests in laboratory using sera from the RPR and TPHA samples, they noted a 97% sensitivity of the rapid tests. They conclude that the assays do not perform well with whole blood
specimens. We suggest that this shortcoming is potentially limited to unheparainzed whole blood.
Furthermore, the poor performance of the Determine TP test reported in terms of positive predictive value (71.4%) is possibly due to use of sequential RPR and TPHA testing as a gold standard to evaluate the TP Determine Test. The authors do not specifically describe the analysis of
specimens that tested positive by TP Determine but negative by the RPR gold standard. We assume that these specimens were considered false positives and therefore contributed to the poor positive predictive value. There are at least two cases where specimens with a positive TP Determine
result might be expected to test negative by RPR: 1) in subjects with a history of treated syphilis because non-treponemal antibodies diminish following proper treatment and 2) in very early and late-stage syphilitic
infection when non-treponemal tests have poorer sensitivity [3]. A more appropriate gold standard might be the direct comparison of the TP Determine test, a treponemal antibody assay, to another treponemal antibody assay (e.g. TPHA or TP-PA alone), in the absence of a preliminary non-treponemal assay (RPR). To minimize false positives, we use the TP
Determine assays in San Francisco as a point-of-care preliminary test in outreach centers only on patients who deny a history of syphilis treatment.
Many previous studies have documented strong validity of rapid syphilis tests with the use of sera [4-6]. Because of the need for point-of-care testing for syphilis without complex laboratory methods, there is a corresponding need for analysis of these same assays with the use of
whole blood. Whether it be the TP Determine or another rapid test for the diagnosis of syphilis, a valid and simple test will be invaluable to control programs in stemming the worldwide morbidity associated with syphilitic infection.
References
1. Campos PE, Buffardi AL, Chiappe M, et al. Utility of the DetermineTM Syphilis TP Rapid Test in Commercial Sex Venues in Peru. Sex Transm Infect 2006
2. Siedner M, Zapitz V, Ishida M, De La Roca R and Klausner JD. Performance of rapid syphilis tests in venous and fingerstick whole blood specimens. Sex Transm Dis 2004;31:557-60
3. Young H. Syphilis: new diagnostic directions. Int J STD AIDS 1992;3:391-413
4. WHO Special Programme for Research and Training in Tropical Diseases (TDR) STD Diagnostics Initiative (SDI). Laboratory-based evaluation of rapid syphilis diagnostics. Diagnostics Evaluation Series 2003;1:1-31
5. Diaz T, Almeida M, Georg I, Maia S, Souza RD and Markowitz L. Evaluation of the Determine rapid syphilis TP assay using sera. Clin Diagn Lab Immunol 2004;11:98-101
6. Herring AJ, Ballard RC, Pope V, et al. A Multi-centre Evaluation of Nine Rapid Point of Care Syphilis Tests Using Archived Sera. Sex Transm Infect 2006
The article by Prost el al.[1] entitled ‘There is such a thing as asking for trouble’: Taking rapid HIV testing to gay venues is fraught with challenges” is an important addition to the growing literature focusing on HIV testing at entertainment venues catering to men who have sex with men (MSM). Their ethnographic approach to exploring the
complexity of such programs adds further dimension to this topic,...
The article by Prost el al.[1] entitled ‘There is such a thing as asking for trouble’: Taking rapid HIV testing to gay venues is fraught with challenges” is an important addition to the growing literature focusing on HIV testing at entertainment venues catering to men who have sex with men (MSM). Their ethnographic approach to exploring the
complexity of such programs adds further dimension to this topic, however their experience should not discourage others from integrating HIV (and other STI) screening in such venues.
In their article, Prost et al [1] identified confidentiality, the apparent disconnect between a serious medical issue and gay life, post-test support, and venue-specific concerns as potentially damaging to venue
based testing for MSM. Since February 2006, the NYU School of Medicine Center for AIDS Research has been conducting a study in New York City bathhouses to assess the feasibility of HIV testing in these venues; to date we performed 406 tests. Many of the points that the authors have made regarding implementation of such a program influenced our study design well before we ever performed our first test. Privacy, risk-reduction counseling, and clear paths connecting those found to be HIV positive to care were central to our design and the design of any successful HIV testing program at bathhouses, saunas, and other commercial
venues. Before we approached the management of the two remaining bathhouses in Manhattan, we studied models described by similar programs successfully functioning in Seattle and Los Angeles.[2]
All of these observations are valid issues facing non-traditional venue HIV rapid testing. It is the charge of the organization developing a venue-specific program to predict these issues rather than to respond to
them. Each issue can be dealt with to create a program that is acceptable and effective.
• Confidentiality
In creating our program, we followed many of the dictums laid out in a successful bathhouse testing program in Seattle.[2] To create an effective program, community ties and the relationship with venue management need to be developed. The testing program becomes a service that is provided by a healthcare or research group in close association with the staff and management of the venues. Maintaining a sustainable program requires working within the culture and environment of the venue, not against it. With the support of the venue management, we converted
unused space into discreet, soundproof, confidential testing rooms.
• HIV testing is “too serious” for an entertainment venue.
In our survey of the men attending one Manhattan bathhouse, nearly 80% of men responded that HIV testing was appropriate in the bathhouse setting. As demonstrated in one study, bathhouse testing may impact behaviors
associated with HIV risk.[3] Part of HIV stigma is the
compartmentalization of sexuality from health. We believe that HIV testing at the bathhouse in a model acceptable to venue staff and patrons makes sexual health an important reality for these MSM. Rather than too serious, our service is just serious enough. This is evidenced by the
fact that many men who choose not to be tested through our program approach testing staff to ask questions about safer sex and HIV exposure. Furthermore, the testing staff report overwhelmingly positive feedback from venue patrons, staff, and management.
• Post-test support/Venue Specific Concerns
No HIV testing program should exist without a good post-test plan. When we discussed our program with venue management, they expressed concern about connection to care and the risk for self-destructive behavior for men with preliminarily positive tests. Ninety-three percent of our
positives have been successfully connected to HIV primary care. Additionally, we have in place a clear and discreet plan to remove anyone from the bathhouse upset by a result. Despite a 5.1% seroprevalence rate among testers there have been no such “evacuations” necessary [4].
Additionally there is no data to support that people newly diagnosed with HIV are at increased risk of suicidal behavior.
The data presented in the study by Prost et al1 confirms many of the assumptions we made in designing a testing protocol in bathhouses in New York City. This valuable addition to the literature should be used to help guide and design such testing programs rather than be used as evidence for why they should not exist. A close understanding of the community of clients such programs will reach as well as a close working relationship with venue management is central in a lifestyle-competent
testing program. Connection to care and safety concerns need to be assumed and planned for in the design of any non-traditional rapid testing program.
The challenge of venue based testing programs is that each city and venue represents its’ own culture. What works in one venue, may not translate well to a different venue. Prost et al [1] identified several critical components in their evaluation of the acceptability of HIV
testing in commercial sex venues in the UK. However, for every venue based HIV testing program that is not accepted by its clients, there are ones that succeed. Our bathhouse screening program in New York has been not only well received by the clients its serves, but also by the larger
prevention community. We hope that readers of Prost et al see opportunities to improve and expand venue based testing programs, and not reasons to abandon them all together.
References
1. Prost A, Chopin M, McOwan A, et al. "There is such a thing as asking for trouble": Taking rapid HIV testing to gay venues is fraught with challenges. Sex Transm Infect 2007
2. Spielberg F, Branson BM, Goldbaum GM, Kurth A and Wood RW. Designing an HIV counseling and testing program for bathhouses: the Seattle experience with strategies to improve acceptability. J Homosex 2003;44:203-20
3. Huebner DM, Binson D, Woods WJ, Dilworth SE, Neilands TB and Grinstead O. Bathhouse-based voluntary counseling and testing is feasible and shows preliminary evidence of effectiveness. J Acquir Immune Defic Syndr
2006;43:239-46
4. Daskalakis DRSRHKB, PhD; Richard Hutt, RN; Dylan Stein; Timothy Neithercott; Ancil Brown; Fred Valentine, MD; Michael Marmor, PhD. Correlates of Incident HIV Diagnosis, Knowledge of Chemoprophylaxis, and
Burden of Acute and Recent Infection among Patrons of new York City Bathhouses, a Pilot Study. In: Conference on Retroviruses and Opportunistic Infections. Los Angeles, CA, 2007
As the editor of the recently published NAM Manual of HIV Prevention and a person living with HIV, I think serosorting is on balance a positive influence on the course of the HIV epidemic and, as Robert Reinhardt says, say, it’s ‘natural selection’. If I’m honest, if I was HIV
negative, I’m not sure if I’d want to have sex with someone with HIV.
But I don’t think serosorting is a good thing in itsel...
As the editor of the recently published NAM Manual of HIV Prevention and a person living with HIV, I think serosorting is on balance a positive influence on the course of the HIV epidemic and, as Robert Reinhardt says, say, it’s ‘natural selection’. If I’m honest, if I was HIV
negative, I’m not sure if I’d want to have sex with someone with HIV.
But I don’t think serosorting is a good thing in itself, and I agree that campaigning specifically for serosorting risks promoting 'viral apartheid'. You cannot legislate against human nature; HIV negative and positive people are going to continue to be attracted to each other and have sex and relationships and this should not become a socially shunned activity.
No, I think serosorting is a good thing because in order to serosort you have to do two things: a) Know your status b) Disclose it.
It’s not serosorting we should be encouraging, it’s the behaviours that make it possible.
Gus Cairns,
Board of Directors
UKC - UK Coalition of People Living with HIV and AIDS
The authors of the cited article on serosorting in San Francisco, including members of the city’s Public Health Department, have created more problems than they have solved due, in part, to the premature rollout in San Francisco of a campaign to actively “encourage” serosorting as a HIV prevention strategy. That campaign was initiated coincidentally when their article was published in STI by means of...
The authors of the cited article on serosorting in San Francisco, including members of the city’s Public Health Department, have created more problems than they have solved due, in part, to the premature rollout in San Francisco of a campaign to actively “encourage” serosorting as a HIV prevention strategy. That campaign was initiated coincidentally when their article was published in STI by means of a press release, a web based campaign and use of other media. 1-2
“Serosorting” has been variously and vaguely defined, even by the authors themselves. 2-4 It is also subject to radically different public perceptions by the at risk community. Although the STI article refers to it as a rather recent phenomenon in terms of effect on HIV incidence, the campaign acknowledges that this new fangled term describes an obvious behavior, in my view one that is much like natural selection, operating over the last 25 years. Most likely its effect on incidence has always
been a background phenomenon. The web campaign states:
"Since the beginning of the epidemic some gay men have been deciding that they prefer to be with someone of the same HIV status. Many men just feel more comfortable having sex with same status men."
Although the term has a clinically-sounding soothing appeal, cool rational “preference” decision making based on considerate comfort levels seems to be stretching the boundaries to describe the deep fears, emotional anxieties, ignorance of transmission and discrimination characteristic of the epidemic then and now. The authors have not evaluated any psychological or emotional determinants of this practice as a prelude to rollout of public prevention program.
Of great concern is that with the health department’s recognition that the study has significant limitations and “remains a hypothesis that needs validation,” the agency’s Prevention Section moved forward on a serosorting based campaign publicly. The admitted limitations include
lack of clear causality, uncertainty of temporal sequence trends in the different ways data are collected, lack of key biological or behavioral information, alternative hypotheses for explaining HIV incidence and the nature of ecological modeling based studies. To those could be added lack of information about comparative circumcision rates recently shown to affect transmission and suspected to apply also in MSM and differentially in racial or ethnic populations.5 The article data do not describe any population influenced differences.
But there are more serious problems with a rollout of a serosorting prevention campaign. None of the epidemiological or ecological studies have evaluated social and other harms that may be expected. These include
legitimizing stigma against HIV infected individuals and ratifying a “pariah” status, unfairly criticizing committed serodiscordant couples because the campaign message is tantamount to telling them they are in the wrong relationship or engaged in practices that may not work, confusing messaging about the viability of other safe sex practices or the benefits of a responsible healthy sexual relationship with discordant partners. The campaign is also illogical in that the agency did not study or embark
on similar campaigns for other serodiscordant risks such as those for heterosexual HPV status.
Other messages described in this public health initiative are welcome and useful. Increasing knowledge, testing, discussion and disclosure are key elements of a prevention program. Encouraging serosorting – as it is
called today –raises a serious risk of return to objectionable, discriminatory and harmful social behaviors based not on what a person does but simply on who they are.
Sincerely,
Robert Reinhard
Community Advisory Board Member, San Francisco Clinical Trials Unit
Email: Robert_Reinhard@worldnet.att.net
References
1. G. Newsom and M. Katz. AIDS Office to Launch new HIV Prevention Campaign. Press release, City and County of San Francisco. November 1, 2006.
2. http://www.disclosehiv.org/
3. Mao L, Crawford JM, Hospers HJ, Prestage GP, Grulich AE, Kaldor JM, Kippax SC.. Serosorting" in casual anal sex of HIV-negative gay men is noteworthy and is increasing in Sydney, Australia. AIDS. 2006 May 12;20(8):1204-6
4. Parsons JT, Severino J, Nanin J, Punzalan JC, von Sternberg K, Missildine W, Frost D. Positive, negative, unknown: assumptions of HIV status among HIV-positive men who have sex with men. AIDS Educ Prev. 2006 Apr;18(2):139-49
5. Centers for Disease Control. Male Circumcision and Risk for HIV Transmission: Implications for the United States. December, 2006.
http://www.cdc.gov/hiv/resources/factsheets/PDF/circumcision.pdf
The authors S Day et al1 should be commended on the performance of their department in the appropriate provision of post-exposure prophylaxis after sexual exposure (PEPSE) in accordance with BASHH
guidelines2.
A co-ordinated post exposure prophylaxis (PEP) policy was introduced at St Mary’s Hospital, London in November 2002, comprising formal links between GUM, A&E and...
The authors S Day et al1 should be commended on the performance of their department in the appropriate provision of post-exposure prophylaxis after sexual exposure (PEPSE) in accordance with BASHH
guidelines2.
A co-ordinated post exposure prophylaxis (PEP) policy was introduced at St Mary’s Hospital, London in November 2002, comprising formal links between GUM, A&E and Occupational Health, and establishing a dedicated PEP
Clinic.
All patients given PEP following sexual or occupational exposures are followed up in this clinic. A retrospective notes audit3 of all clinic attendees was conducted over a 6 month period in 2003, comparing our service with outcome measures highlighted in national guidelines at the time.45
From June to November 2003, 48 patients attended. 54% had occupational exposures. Of the 46% with non-occupational exposures, 27% were sexually exposed (n=13).
Management of our PEPSE recipients has subsequently been compared with BASHH guidelines2.
85% presented for PEPSE via the GUM clinic, 15% via A&E. Demographics, sexual exposures, and attendance for follow up HIV tests, are presented in Table 1.
In 6 of the 13 sexual exposures, the partner was known to be HIV positive, 5 had untraceable partners of unknown serostatus, and in the final case the partner was traced and tested HIV negative on the day of exposure. This patient was not prescribed PEPSE.
PEPSE was in line with ‘recommended’ indications in 11 of the 12 remaining cases. One patient presented after receptive oral sex with a known HIV positive partner, and was concerned that he had bleeding gums. This fell in line with a ‘considered’ indication according to guidelines.
Hence 100% of PEPSE prescriptions fell within recommended guidelines2 (BASHH target 90%).
Time from exposure to first dose was not documented in 1 patient, the remainder received PEPSE within 72 hours (90% target); Range 13-54 hours, mean 28 hours.
100% of PEPSE recipients completed the full 28day course of standard PEP - Combivir, Nelfinavir at the time of audit, (75% target).
Our co-ordinated approach to the provision of PEP has enabled us to provide a successful service. PEPSE is easily accessible, appropriately prescribed, and high completion rates were observed, with no discontinuations related to adverse events. The high adherence rates may have been related to the continuity of seeing the same SpR in clinic
throughout the month of treatment. If appropriate, patients were also referred promptly to clinical psychology services (25% of our cohort) for further adherence support and discussion about sexual risk taking.
At the time of audit we saw comparatively few patients requiring PEPSE. Given recent media coverage, awareness of PEPSE amongst MSM in London has significantly increased – 12 patients requesting PEPSE at St Mary’s in the last 2 weeks alone.
The authors rightly suggest that a PEPSE follow up clinic and dedicated proforma would help ensure appropriate prescription, aid adherence and completion of PEPSE, and improve attendance rates for follow up serology. Certainly the success of our PEP Clinic concurs with this suggestion.
References
1. Post-exposure HIV prophylaxis following sexual exposure:a retrospective adduct against recent draft BASHH guidance. Day S et al. STI 2006;82:236-237
2. BASHH. United Kingdom guideline for the use of post-exposure prophylaxis for HIV following sexual exposure. Fisher M et al. Int J.STD&AIDS 2006;17:81-92
3. A co-ordinated approach to HIV Post Exposure Prophylaxis ensures appropriate and high completion rates. L. Sathia, C Collister, J Walsh. Post Presentation at 7th International Conference on Drug Therapy, Glasgow, Nov '04.
4. HIV Post exposure Prophylaxis - Guidance from the UK chief medical officers expert advisory group on AIDS Revised February 2004 - available at http://www.advisorybodies.doh.gov.uk/eaga/publications.htm
5. Clinical Effectiveness Group (British Association of Sexual Health and HIV) - United Kingdom Guideline for the use of Post-Exposure Prophylaxis for HIV following sexual Exposure available at:
http://www.bashh.org/guidelines/2006/pepse_0206.pdf
In their study Edwards et al. found that the prevalence of sex exchange for money or drugs is approximately 3.5% among the general population of United States adolescents (1). Despite this being a very
worthwhile and understudied area of research, as a researcher and clinician, I have a serious concerns about the data used for this study and the accuracy of the analysis used. Gordis (2) noted that, “...
In their study Edwards et al. found that the prevalence of sex exchange for money or drugs is approximately 3.5% among the general population of United States adolescents (1). Despite this being a very
worthwhile and understudied area of research, as a researcher and clinician, I have a serious concerns about the data used for this study and the accuracy of the analysis used. Gordis (2) noted that, “No
scientific discipline can be better than the quality of its raw data,” and, unfortunately, Edwards, et al. did not take into consideration conditional prevalence in their analysis.
The 3.5% prevalence rate of adolescents who exchange sex for money was derived from self-reports on a single survey item. In other survey questions, the adolescents were asked about engaging in vaginal and anal sex. The adolescents who answered these items in the affirmative do not account for 100% of the adolescents who reported exchanging sex. The authors assumed that the respondents who had exchanged sex, but had not engaged in vaginal and/or anal sex, must have exchanged oral sex. However, there is no evidence to back up this assumption, since the survey did not gather data on oral sex behaviour. Without this information, the possibility that the respondents were confused or simply lied about behaviour is simply too strong, leading to doubts of the accuracy of the results. Therefore, the researchers should have only analyzed the data on survey respondents who answered positively to having vaginal and/or anal sex as well as to having exchanged sex for money or drugs. Although it would have meant a much smaller sample size, the study’s findings would have been more accurate and therefore more helpful to clinicians and researchers alike.
Sincerely,
Karen Matta Oshima, MSW, LICSW
Doctoral Student,
George Warren Brown School of Social Work
References
1. Edwards, JM, Iritani, BJ, and Hallfors, DD. Prevalence and correlates of exchanging sex for drugs or money among adolescents in the United States. STI Published Online First: 10 August 2006.
doi:10.1136/sti.2006.020693.
2. Gordis, L. Assuring the quality of questionnaire data in epidemiological research. American Journal of Epidemiology 1979; 109: 21-24.
Roberts et al (1) have undertaken an ambitious task to critique economic evaluations and mathematical modelling of this topic, and have raised pertinent issues about modelling fidelity. I wish to correct their
reference to my contribution to the field, which has been described as an 'undefined "mathematical model"'. A table in my paper (2) summarised the adapted Markov model with its six inbuilt feedback l...
Roberts et al (1) have undertaken an ambitious task to critique economic evaluations and mathematical modelling of this topic, and have raised pertinent issues about modelling fidelity. I wish to correct their
reference to my contribution to the field, which has been described as an 'undefined "mathematical model"'. A table in my paper (2) summarised the adapted Markov model with its six inbuilt feedback loops allowing estimation of the impact of undetected infection, incomplete treatment,
and partner factors including reinfection. My paper also informed the reader (on page 10) that this was a second order Monte Carlo simulation, running a hypothetical cohort of 100,000 young women through 2,000 iterations. This dynamic population-based model has subsequently been used
to address screening issues: most recently the question of cost saving by pooling urine samples for mass screening in low prevalence situations. A paper on this research will shortly be submitted for publication.
Roberts et al have suggested publication lead time is a reason for the paucity of papers that have described their models in detail. My own experience would indicate that publication bias also operates here: it is much easier to publish an editorial-style paper outlining results obtained
from modelling than to publish the details of the actual mathematical method, especially in journals with clinical readership.
References
(1) Roberts TE, Robinson S, Barton P, Bryan S, Low N. Screening for Chlamydia trachomatis: a systematic review of the economic evaluations and modelling. Sexually Transmitted Infections. 2006; 82: 193-200.
(2) Moriarty HJ. Mathematical modelling: what it can offer to sexual health. Venerology. 2001; 14: 7-13.
In their study, Apoola et al found that patient referral was the most favoured method of partner notification in a large sample of GUM clinics
attendees (1).
Their observations are in line with our findings in a recent (2006) survey in an age- and gender stratified sample of the general population in Flanders, Belgium.
Three hundred patients were questioned regarding acceptability of partn...
In their study, Apoola et al found that patient referral was the most favoured method of partner notification in a large sample of GUM clinics
attendees (1).
Their observations are in line with our findings in a recent (2006) survey in an age- and gender stratified sample of the general population in Flanders, Belgium.
Three hundred patients were questioned regarding acceptability of partner notification strategies in the hypothetical case that they would be diagnosed with an STI.
The large majority of respondents preferred partner
notification (95.8 %). A small minority of respondents indicated that provider referral was acceptable; the provider could be a GP (12.6 %) or another health worker (6.6 %). This pattern was independent of gender,
age, level of education, sexual orientation, number of sexual partners, a history of STIs, and a history of being tested for STIs. In multivariate analysis, older age was slightly associated with the likelihood of accepting provider referral strategies.
Only two respondents stated that they would not inform their partner(s) in case they were diagnosed with an STI.
It remains to be seen to what extent these patients’ preferences in both studies reflect a true believe that being informed directly by a partner is the most optimal strategy for notifying people of a potential STI risk.
It is also conceivable that, by choosing for this strategy, patients try to stay in control over which information on possible STI transmission is disclosed to whom of their regular or occasional sex partners.
A meta-analysis of notification strategies found that patient referral is less effective than provider referral with respect to the number of partners notified and presenting for medical evaluation (2). The reluctance of patients to notify their partners may suggest that they
expect harms from doing so. Potential harms of partner notification, such as the rate of domestic violence, abuse or breaking up of relationships, are poorly understood and need further attention.
References
1. Apoola A, Radcliffe KW, Das S, Robshaw V, Gilleran G, Kumari BS, Boothby M, Rajakumar R. Patient preferences for partner notification. Sex Transm Infect. 2006;82:327-9.
2. Mathews C, Coetzee N, Zwarenstein M, Lombard C, Guttmacher S, Oxman A, Schmid G. Strategies for partner notification for sexually transmitted diseases. Cochrane Database Syst Rev. 2001;4:CD002843.
Low and colleagues used record linkage to identify specific
reproductive health outcomes in women who had or have not had a chlamydia
test. In their paper they refer to "tests done for any purpose as
screening tests". In their analysis they took the "temporal sequence of
chlamydia testing and development of consequences" into account. The most
important finding of this study was the absence of any...
Low and colleagues used record linkage to identify specific
reproductive health outcomes in women who had or have not had a chlamydia
test. In their paper they refer to "tests done for any purpose as
screening tests". In their analysis they took the "temporal sequence of
chlamydia testing and development of consequences" into account. The most
important finding of this study was the absence of any protective effect
of chlamydia testing even for those who tested negative.
Probability of outcome according to chlamydia screen result:
PID: Never tested 2.9%(2.2-2.5%) Negative test 4.0% (3.7-4.4%); Ectopic
pregnancy: Never tested 1.9% (1.7-2.1%) Negative test 2.0% (1.8-2.3%);
Infertility: Never tested 3.1% (2.8-3.3%) Negative test 4.7% (4.4-5.1%).
This is even more surprising as some tests were performed in antenatal
care and thus recruited a population at below average risk for
infertility.
It is of course possible that Low et al did not report the results
chlamydia screening but of chlamydia testing for a variety of indications.
Some patients may have had their tests performed as a part of
investigations for pelvic pain/PID or infertility even if the temporal
sequence was observed as the date of the test (on admission to the
hospital) may have preceded the diagnosis (on discharge from hospital).
Similarly, chlamydia testing may have been performed as a part of an
infertility investigation. Differences in health care seeking behaviour
offer an alternative explanation for the high incidence of PID and
infertility in chlamydia test negative women. To be diagnosed with
infertility or PID a patient has to seek health care. Women who were
tested for chlamydia may be more inclined to use healthcare for other
indications than women who never tested. Interestingly there was no
significant association between the chlamydia testing and ectopic
pregnancy where the diagnosis is unlikely to be affected by health care
seeking behaviour.
It is not inconceivable that chlamydia screening could be seen as
increasing the likelihood of PID or infertility as a negative test could
give false reassurance that risk taking is not harmful. Explaining the
higher incidence of PID and infertility in women who had only negative
chlamydia tests as compared to women who never tested is therefore
essential for the survival of chlamydia screening programmes.
References
(1) Low N, Egger M, Sterne JAC, Harbord RM, Ibrahim F, Lindblom B et al.
Incidence of severe reproductive tract complications associated with
diagnosed genital chlamydial infection: the Uppsala Women's Cohort Study.
Sex Transm Infect 2006;82:212-8.
Dear Editor,
In her recent editorial, Judith Stephenson highlighted the lack of trial evidence supporting the opportunistic approach used by the National Chlamydia Screening Programme (NCSP) and calls for a randomised control trial (RCT) to compare opportunistic versus a register based call/recall approach to screening1. What this editorial and the National Institute for Health and Clinical Evidence (NICE...
In their manuscript, Utility of the Determine TP Rapid Syphilis Test in Commercial Sex Venues in Peru, Campos et al. report poor validity and utility of a point-of-care rapid syphilis assay in an outreach facility for commercial sex workers in urban Peru [1]. We have identified potential limitations in their study design, which might have contributed to their conclusion that the TP Determine Rapid Syphilis Te...
Dear Editor,
The article by Prost el al.[1] entitled ‘There is such a thing as asking for trouble’: Taking rapid HIV testing to gay venues is fraught with challenges” is an important addition to the growing literature focusing on HIV testing at entertainment venues catering to men who have sex with men (MSM). Their ethnographic approach to exploring the complexity of such programs adds further dimension to this topic,...
Dear Editor,
As the editor of the recently published NAM Manual of HIV Prevention and a person living with HIV, I think serosorting is on balance a positive influence on the course of the HIV epidemic and, as Robert Reinhardt says, say, it’s ‘natural selection’. If I’m honest, if I was HIV negative, I’m not sure if I’d want to have sex with someone with HIV.
But I don’t think serosorting is a good thing in itsel...
Dear Editor,
The authors of the cited article on serosorting in San Francisco, including members of the city’s Public Health Department, have created more problems than they have solved due, in part, to the premature rollout in San Francisco of a campaign to actively “encourage” serosorting as a HIV prevention strategy. That campaign was initiated coincidentally when their article was published in STI by means of...
Dear Editor,
The authors S Day et al1 should be commended on the performance of their department in the appropriate provision of post-exposure prophylaxis after sexual exposure (PEPSE) in accordance with BASHH guidelines2.
A co-ordinated post exposure prophylaxis (PEP) policy was introduced at St Mary’s Hospital, London in November 2002, comprising formal links between GUM, A&E and...
Dear Editor,
In their study Edwards et al. found that the prevalence of sex exchange for money or drugs is approximately 3.5% among the general population of United States adolescents (1). Despite this being a very worthwhile and understudied area of research, as a researcher and clinician, I have a serious concerns about the data used for this study and the accuracy of the analysis used. Gordis (2) noted that, “...
Dear Editor
Roberts et al (1) have undertaken an ambitious task to critique economic evaluations and mathematical modelling of this topic, and have raised pertinent issues about modelling fidelity. I wish to correct their reference to my contribution to the field, which has been described as an 'undefined "mathematical model"'. A table in my paper (2) summarised the adapted Markov model with its six inbuilt feedback l...
Dear Editor,
In their study, Apoola et al found that patient referral was the most favoured method of partner notification in a large sample of GUM clinics attendees (1).
Their observations are in line with our findings in a recent (2006) survey in an age- and gender stratified sample of the general population in Flanders, Belgium.
Three hundred patients were questioned regarding acceptability of partn...
Dear Editor,
Low and colleagues used record linkage to identify specific reproductive health outcomes in women who had or have not had a chlamydia test. In their paper they refer to "tests done for any purpose as screening tests". In their analysis they took the "temporal sequence of chlamydia testing and development of consequences" into account. The most important finding of this study was the absence of any...
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