Valuing the health states associated with Chlamydia trachomatis infections and their sequelae: a systematic review of economic evaluations and primary studies

The serodiagnositic value of Chlamydia trachomatis antigens in antibody detection using luciferase immunosorbent assay

Introduction

Among the different antigens used in the detection of anti-Chlamydia trachomatis antibodies, significant differences in sensitivity and specificity have been observed. Further evaluation of C. trachomatis antigens in antibody detection is urgently needed for the development and application of C. trachomatis serologic assays.

Methods

Chlamydia trachomatis antigens Pgp3, TmeA, InaC, and HSP60 were selected and used in luciferase immunosorbent assay (LISA). The detection results obtained from well-defined C. trachomatis positive and negative samples were compared with the commercial C. trachomatis ELISA (Mikrogen) for performance evaluation.

Results

Pgp3, TmeA, InaC, and HSP60-based LISA showed sensitivity of 92.8, 88.8, 90.4, and 94.4%, and specificity of 99.2, 99.2, 99.2, and 92%, respectively. ROC analysis indicated that Pgp3-based LISA showed similar performance to Mikrogen ELISA (AUC 0.986 vs. 0.993, p = 0.207). Furthermore, four C. trachomatis antigens achieved strong diagnostic efficiency, i.e., positive likelihood ratios [+LR] ≥ 10 in C. trachomatis-infected women and negative likelihood ratios [-LR] ≤ 0.1 in C. trachomatis negative low exposure risk children, but only Pgp3 and TmeA showed strong diagnostic value in general adults. In addition, Pgp3, TmeA, and InaC, but not HSP60, achieved high performance, i.e., both positive predictive value (PPV) and negative predictive value (NPV) ≥ 90.9%, and showed no significant cross-reactivity with anti-Chlamydiapneumoniae.

Conclusion

Three C. trachomatis species-specific antigens Pgp3, TmeA, and InaC show superior performance in the detection of anti-C. trachomatis antibody, indicating the potential to be used in developing C. trachomatis serologic tests.

Ignored and undervalued in public health: a systematic review of health state utility values associated with syphilis infection

BACKGROUND

Syphilis is a sexually transmitted infection causing significant global morbidity and mortality. To inform policymaking and economic evaluation studies for syphilis, we summarised utility and disability weights for health states associated with syphilis.

METHODS

We conducted a systematic review, searching six databases for economic evaluations and primary valuation studies related to syphilis from January 2000 to February 2022. We extracted health state utility values or disability weights, including identification of how these were derived. The study was registered in the international prospective register of systematic reviews (PROSPERO, CRD42021230035).

FINDINGS

Of 3401 studies screened, 22 economic evaluations, two primary studies providing condition-specific measures, and 13 burden of disease studies were included. Fifteen economic evaluations reported outcomes as disability-adjusted life years (DALYs) and seven reported quality-adjusted life years (QALYs). Fourteen of 15 economic evaluations that used DALYS based their values on the original Global Burden of Disease (GBD) study from 1990 (published in 1996). For the seven QALY-related economic evaluations, the methodology varied between studies, with some studies using assumptions and others creating utility weights or converting them from disability weights.

INTERPRETATION

We found a limited evidence base for the valuation of health states for syphilis, a lack of transparency for the development of existing health state utility values, and inconsistencies in the application of these values to estimate DALYs and QALYs. Further research is required to expand the evidence base so that policymakers can access accurate and well-informed economic evaluations to allocate resources to address syphilis and implement syphilis programs that are cost-effective.

Costs, Health Benefits, and Cost-Effectiveness of Chlamydia Screening and Partner Notification in the United States, 2000-2019: A Mathematical Modeling Analysis

BACKGROUND

Chlamydia remains a significant public health problem that contributes to adverse reproductive health outcomes. In the United States, sexually active women 24 years and younger are recommended to receive annual screening for chlamydia. In this study, we evaluated the impact of estimated current levels of screening and partner notification (PN), and the impact of screening based on guidelines on chlamydia associated sequelae, quality adjusted life years (QALYs) lost and costs.

METHODS

We conducted a cost-effectiveness analysis of chlamydia screening, using a published calibrated pair formation transmission model that estimated trends in chlamydia screening coverage in the United States from 2000 to 2015 consistent with epidemiological data. We used probability trees to translate chlamydial infection outcomes into estimated numbers of chlamydia-associated sequelae, QALYs lost, and health care services costs (in 2020 US dollars). We evaluated the costs and population health benefits of screening and PN in the United States for 2000 to 2015, as compared with no screening and no PN. We also estimated the additional benefits that could be achieved by increasing screening coverage to the levels indicated by the policy recommendations for 2016 to 2019, compared with screening coverage achieved by 2015.

RESULTS

Screening and PN from 2000 to 2015 were estimated to have averted 1.3 million (95% uncertainty interval [UI] 490,000-2.3 million) cases of pelvic inflammatory disease, 430,000 (95% UI, 160,000-760,000) cases of chronic pelvic pain, 300,000 (95% UI, 104,000-570,000) cases of tubal factor infertility, and 140,000 (95% UI, 47,000-260,000) cases of ectopic pregnancy in women. We estimated that chlamydia screening and PN cost $9700 per QALY gained compared with no screening and no PN. We estimated the full realization of chlamydia screening guidelines for 2016 to 2019 to cost $30,000 per QALY gained, compared with a scenario in which chlamydia screening coverage was maintained at 2015 levels.

DISCUSSION

Chlamydia screening and PN as implemented in the United States from 2000 through 2015 has substantially improved population health and provided good value for money when considering associated health care services costs. Further population health gains are attainable by increasing screening further, at reasonable cost per QALY gained.

Behavioural intervention to reduce sexually transmitted infections in people aged 16–24 years in the UK: the safetxt RCT

Background

The prevalence of genital chlamydia and gonorrhoea is higher in the 16–24 years age group than those in other age group. With users, we developed the theory-based safetxt intervention to reduce sexually transmitted infections.

Objectives

To establish the effect of the safetxt intervention on the incidence of chlamydia/gonorrhoea infection at 1  year.

Design

A parallel-group, individual-level, randomised superiority trial in which care providers and outcome assessors were blinded to allocation.

Setting

Recruitment was from 92 UK sexual health clinics.

Participants

Inclusion criteria were a positive chlamydia or gonorrhoea test result, diagnosis of non-specific urethritis or treatment started for chlamydia/gonorrhoea/non-specific urethritis in the last 2 weeks; owning a personal mobile phone; and being aged 16–24 years.

Allocation

Remote computer-based randomisation with an automated link to the messaging system delivering intervention or control group messages.

Intervention

The safetxt intervention was designed to reduce sexually transmitted infection by increasing partner notification, condom use and sexually transmitted infection testing before sex with new partners. It employed educational, enabling and incentivising content delivered by 42–79 text messages over 1 year, tailored according to type of infection, gender and sexuality.

Comparator

A monthly message regarding trial participation.

Main outcomes

The primary outcome was the incidence of chlamydia and gonorrhoea infection at 12 months, assessed using nucleic acid amplification tests. Secondary outcomes at 1 and 12 months included self-reported partner notification, condom use and sexually transmitted infection testing prior to sex with new partner(s).

Results

Between 1 April 2016 and 23 November 2018, we assessed 20,476 people for eligibility and consented and randomised 6248 participants, allocating 3123 to the safetxt intervention and 3125 to the control. Primary outcome data were available for 4675 (74.8%) participants. The incidence of chlamydia/gonorrhoea infection was 22.2% (693/3123) in the intervention group and 20.3% (633/3125) in the control group (odds ratio 1.13, 95% confidence interval 0.98 to 1.31). There was no evidence of heterogeneity in any of the prespecified subgroups. Partner notification was 85.6% in the intervention group and 84.0% in the control group (odds ratio 1.14, 95% confidence interval 0.99 to 1.33). At 12 months, condom use at last sex was 33.8% in the intervention group and 31.2% in the control group (odds ratio 1.14, 95% confidence interval 1.01 to 1.28) and condom use at first sex with most recent new partner was 54.4% in the intervention group and 48.7% in the control group (odds ratio 1.27, 95% confidence interval 1.11 to 1.45). Testing before sex with a new partner was 39.5% in the intervention group and 40.9% in the control group (odds ratio 0.95, 95% confidence interval 0.82 to 1.10). Having two or more partners since joining the trial was 56.9% in the intervention group and 54.8% in the control group (odds ratio 1.11, 95% confidence interval 1.00 to 1.24) and having sex with someone new since joining the trial was 69.7% in the intervention group and 67.4% in the control group (odds ratio 1.13, 95% confidence interval 1.00 to 1.28). There were no differences in safety outcomes. Additional sensitivity and per-protocol analyses showed similar results.

Limitations

Our understanding of the mechanism of action for the unanticipated effects is limited.

Conclusions

The safetxt intervention did not reduce chlamydia and gonorrhoea infections, with slightly more infections in the intervention group. The intervention increased condom use but also increased the number of partners and new partners. Randomised controlled trials are essential for evaluating health communication interventions, which can have unanticipated effects.

Future work

Randomised controlled trials evaluating novel interventions in this complex area are needed.

Trial registration

This trial is registered as ISRCTN64390461.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 11, No. 1. See the NIHR Journals Library website for further project information.

Evaluating the impact and cost-effectiveness of chlamydia management strategies in Hong Kong: A modeling study

Objectives

To illustrate the epidemiologic and cost-effectiveness impact of shifting the focus from population-based screening toward a targeted management approach for genital chlamydia infection.

Design

Modeling study, implementing an individual-based, stochastic, dynamic network model.

Setting

Hong Kong.

Population

A hypothetical sample network of 10,000 people with a partnership distribution based on Hong Kong's sexually active population of reproductive age (age 18–49 years).

Interventions

In this study, we present several scenarios with different implementations of universal vs. targeted screening (based on partner numbers). We also explored the impact of (1) screening only, (2) screening plus expedited partner therapy, and (3) screening plus partner testing.

Primary outcome measures

Change of chlamydia prevalence before and after implementing the different strategies. The cost-effectiveness analysis reports total direct cost from a health provider perspective, the QALYs gained, and incremental cost-effectiveness ratios (ICER).

Results

In comparing the effects of universal screening only and targeted screening of the high-risk population, the mean prevalence during the 10th year of intervention was 2.75 ± 0.30% and 2.35 ± 0.21%, respectively (compared with 3.24 ± 0.30% and 3.35 ± 0.21% before the interventions, respectively). The addition of contact tracing to the latter targeted screening scenario reduces the mean prevalence during the 10th year of intervention to 1.48 ± 0.13% (compared with 3.31 ± 0.33% at baseline) in the best-case of testing before treatment and maximal contact-tracing effectiveness (40%). Overall, the most effective scenarios were those for which interventions focused on the high-risk population defined by the number of partners, with contact tracing included. The ICER for targeted screening with contact tracing at 20% and 40% efficiency was $4,634 and $7,219 per QALY gained, respectively (10-year time horizon). Expedited partner therapy did not significantly impact overall chlamydia prevalence and caused overtreatment.

Conclusions

Our study suggests that targeted screening with strengthened contact tracing efforts is the most cost-effective strategy to reduce the prevalence of chlamydia in Hong Kong.

Methodological considerations in the assessment of direct and indirect costs of back pain: A systematic scoping review

Background

Back pain is a common and costly health problem worldwide. There is yet a lack of consistent methodologies to estimate the economic burden of back pain to society.

Objective

To systematically evaluate the methodologies used in the published cost of illness (COI) literature for estimating the direct and indirect costs attributed to back pain, and to present a summary of the estimated cost burden.

Methods

Six electronic databases were searched to identify COI studies of back pain published in English up to February 2021. A total of 1,588 abstracts were screened, and 55 full-text studies were subsequently reviewed. After applying the inclusion criteria, 45 studies pertaining to the direct and indirect costs of back pain were analysed.

Results

The studies reported data on 15 industrialised countries. The national cost estimates of back pain in 2015 USD ranged from $259 million ($29.1 per capita) in Sweden to $71.6 billion ($868.4 per capita) in Germany. There was high heterogeneity among the studies in terms of the methodologies used for analysis and the resulting costs reported. Most of the studies assessed costs from a societal perspective (n = 29). The magnitude and accuracy of the reported costs were influenced by the case definition of back pain, the source of data used, the cost components included and the analysis method. Among the studies that provided both direct and indirect cost estimates (n = 15), indirect costs resulting from lost or reduced work productivity far outweighed the direct costs.

Conclusion

Back pain imposes substantial economic burden on society. This review demonstrated that existing published COI studies of back pain used heterogeneous approaches reflecting a lack of consensus on methodology. A standardised methodological approach is required to increase credibility of the findings of COI studies and improve comparison of estimates across studies.

Screening for chlamydia and/or gonorrhea in primary health care: systematic reviews on effectiveness and patient preferences

BACKGROUND

We conducted systematic reviews on the benefits and harms of screening compared with no screening or alternative screening approaches for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in non-pregnant sexually active individuals, and on the relative importance patients' place on the relevant outcomes. Findings will inform recommendations by the Canadian Task Force on Preventive Health Care.

METHODS

We searched five databases (to January 24, 2020), trial registries, conference proceedings, and reference lists for English and French literature published since 1996. Screening, study selection, and risk of bias assessments were independently undertaken by two reviewers, with consensus for final decisions. Data extraction was conducted by one reviewer and checked by another for accuracy and completeness. Meta-analysis was conducted where appropriate. We used the GRADE approach to rate the certainty of the evidence. The Task Force and content experts provided input on determining thresholds for important effect sizes and on interpretation of findings.

RESULTS

Of 41 included studies, 17 and 11 reported on benefits and harms of screening, respectively, and 14 reported on patient preferences. Universal screening for CT in general populations 16 to 29 years of age, using population-based or opportunistic approaches achieving low screening rates, may make little-to-no difference for a female's risk of pelvic inflammatory disease (PID) (2 RCTs, n=141,362; 0.3 more in 1000 [7.6 fewer to 11 more]) or ectopic pregnancy (1 RCT, n=15,459; 0.20 more per 1000 [2.2 fewer to 3.9 more]). It may also not make a difference for CT transmission (3 RCTs, n=41,709; 3 fewer per 1000 [11.5 fewer to 6.9 more]). However, benefits may be achieved for reducing PID if screening rates are increased (2 trials, n=30,652; 5.7 fewer per 1000 [10.8 fewer to 1.1 more]), and for reducing CT and NG transmission when intensely screening high-prevalence female populations (2 trials, n=6127; 34.3 fewer per 1000 [4 to 58 fewer]; NNS 29 [17 to 250]). Evidence on infertility in females from CT screening and on transmission of NG in males and both sexes from screening for CT and NG is very uncertain. No evidence was found for cervicitis, chronic pelvic pain, or infertility in males from CT screening, or on any clinical outcomes from NG screening. Undergoing screening, or having a diagnosis of CT, may cause a small-to-moderate number of people to experience some degree of harm, mainly due to feelings of stigmatization and anxiety about future infertility risk. The number of individuals affected in the entire screening-eligible population is likely smaller. Screening may make little-to-no difference for general anxiety, self-esteem, or relationship break-up. Evidence on transmission from studies comparing home versus clinic screening is very uncertain. Four studies on patient preferences found that although utility values for the different consequences of CT and NG infections are probably quite similar, when considering the duration of the health state experiences, infertility and chronic pelvic pain are probably valued much more than PID, ectopic pregnancy, and cervicitis. How patients weigh the potential benefits versus harms of screening is very uncertain (1 survey, 10 qualitative studies); risks to reproductive health and transmission appear to be more important than the (often transient) psychosocial harms.

DISCUSSION

Most of the evidence on screening for CT and/or NG offers low or very low certainty about the benefits and harms. Indirectness from use of comparison groups receiving some screening, incomplete outcome ascertainment, and use of outreach settings was a major contributor to uncertainty. Patient preferences indicate that the potential benefits from screening appear to outweigh the possible harms. Direct evidence about which screening strategies and intervals to use, which age to start and stop screening, and whether screening males in addition to females is necessary to prevent clinical outcomes is scarce, and further research in these areas would be informative. Apart from the evidence in this review, information on factors related to equity, acceptability, implementation, cost/resources, and feasibility will support recommendations made by the Task Force.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42018100733 .

Assessing the costs and outcomes of control programmes for sexually transmitted infections: a systematic review of economic evaluations

OBJECTIVE

To identify economic evaluations of interventions to control STIs and HIV targeting young people, and to assess how costs and outcomes are measured in these studies.

DESIGN

Systematic review.

DATA SOURCES

Seven databases were searched (Medline (Ovid), EMBASE (Ovid), Web of Science, PsycINFO, NHS Economic Evaluation Database, NHS Health Technology Assessment and Database of Abstracts of Reviews of Effects) from January 1999 to April 2019. Key search terms were STIs (chlamydia, gonorrhoea, syphilis) and HIV, cost benefit, cost utility, economic evaluation, public health, screening, testing and control.

REVIEW METHODS

Studies were included that measured costs and outcomes to inform an economic evaluation of any programme to control STIs and HIV targeting individuals predominantly below 30 years of age at risk of, or affected by, one or multiple STIs and/or HIV in Organisation for Economic Co-operation and Development countries. Data were extracted and tabulated and included study results and characteristics of economic evaluations. Study quality was assessed using the Philips and BMJ checklists. Results were synthesised narratively.

RESULTS

9530 records were screened and categorised. Of these, 31 were included for data extraction and critical appraisal. The majority of studies assessed the cost-effectiveness or cost-utility of screening interventions for chlamydia from a provider perspective. The main outcome measures were major outcomes averted and quality-adjusted life years. Studies evaluated direct medical costs, for example, programme costs and 11 included indirect costs, such as productivity losses. The study designs were predominantly model-based with significant heterogeneity between the models.

DISCUSSION/CONCLUSION

None of the economic evaluations encompassed aspects of equity or context, which are highly relevant to sexual health decision-makers. The review demonstrated heterogeneity in approaches to evaluate costs and outcomes for STI/HIV control programmes. The low quality of available studies along with the limited focus, that is, almost all studies relate to chlamydia, highlight the need for high-quality economic evaluations to inform the commissioning of sexual health services.

Perceptions and Experiences of Internet-Based Testing for Sexually Transmitted Infections: Systematic Review and Synthesis of Qualitative Research

Background

Internet-based testing for sexually transmitted infections (STIs) allows asymptomatic individuals to order a self-sampling kit online and receive their results electronically, reducing the need to attend a clinic unless for treatment. This approach has become increasingly common; however, there is evidence that barriers exist to accessing it, particularly among some high-risk populations. We review the qualitative evidence on this topic, as qualitative research is well-placed to identify the complex influences that relate to accessing testing.

Objective

This paper aims to explore perceptions and experiences of internet-based testing for STIs among users and potential users.

Methods

Searches were run through 5 electronic databases (CINAHL, EMBASE, MEDLINE, PsycINFO, and Web of Science) to identify peer-reviewed studies published between 2005 and 2018. Search terms were drawn from 4 categories: STIs, testing or screening, digital health, and qualitative methods. Included studies were conducted in high-income countries and explored patient perceptions or experiences of internet-based testing, and data underwent thematic synthesis.

Results

A total of 11 studies from the 1735 studies identified in the initial search were included in the review. The synthesis identified that internet-based testing is viewed widely as being acceptable and is preferred over clinic testing by many individuals due to perceived convenience and anonymity. However, a number of studies identified concerns relating to test accuracy and lack of communication with practitioners, particularly when receiving results. There was a lack of consensus on preferred media for results delivery, although convenience and confidentiality were again strong influencing factors. The majority of included studies were limited by the fact that they researched hypothetical services.

Conclusions

Internet-based testing providers may benefit from emphasizing this testing’s comparative convenience and privacy compared with face-to-face testing in order to improve uptake, as well as alleviating concerns about the self-sampling process. There is a clear need for further research exploring in depth the perceptions and experiences of people who have accessed internet-based testing and for research on internet-based testing that explicitly gathers the views of populations that are at high risk of STIs.

Trial Registration

PROSPERO CRD42019146938; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=146938

A Systematic Literature Review of Reviews on the Effectiveness of Chlamydia Testing

Chlamydia trachomatis is the most common bacterial sexually transmitted infection, causing significant morbidity and economic burden. Strategies like national screening programs or home-testing kits were introduced in some developed countries, yet their effectiveness remains controversial. In this systematic review, we examined reviews of chlamydia screening interventions to assess their effectiveness and the elements that contribute to their success to guide public policy and future research. We assessed English material published after 2000 in PubMed, the Cochrane Library, the British Nursing Index, Medical Database, and Sociological Abstracts, in addition to World Health Organization Global Health Sector Strategies, the European Center for Disease Prevention and Control guidelines, and the Prospective Register of Systematic Reviews. Systematic reviews that focused on chlamydia screening interventions were included. Using the socioecological model, we examined the levels of interventions that may affect the uptake of chlamydia screening. A total of 19 systematic reviews were included. Self-collection in home-testing kits significantly increased screening among girls and women 14-50 years of age. At the organizational level, using electronic health records and not creating additional costs facilitated testing. At the community level, outreach interventions in community and parent centers and homeless shelters achieved high screening rates. At the policy level, interventions with educational and advisory elements could result in significant improvements in screening rates.

Antibody Testing in Estimating Past Exposure to Chlamydia trachomatis in the Netherlands Chlamydia Cohort Study

The asymptomatic course of Chlamydia trachomatis (CT) infections can result in underestimated CT lifetime prevalence. Antibody testing might improve this estimate. We assessed CT antibody positivity and predictive factors thereof in the Netherlands Chlamydia Cohort Study. Women who had ≥1 CT Nucleic Acid Amplification Test (NAAT) in the study (2008–2011) and who provided self-reported information on NAATs were tested for CT major outer membrane protein specific IgG in serum (2016). CT antibody positivity was assessed and predictive factors were identified using multivariable logistic regressions, separately for CT-positive women (≥1 positive NAAT or ≥1 self-reported positive CT test) and CT-negative women (negative by study NAAT and self-report). Of the 3,613 women studied, 833 (23.1%) were CT -positive. Among the CT-negative women, 208 (7.5%, 95% CI 6.5–8.5) tested positive for CT antibodies. This increased CT lifetime prevalence with 5.8% (95% CI 5.0–6.5). Among women with a CT-positive history, 338 (40.6%, 95% CI 38.5–44.1) tested positive. Predictive factors for antibody positivity related to lower social economic status, sexual risk behavior, multiple infections, higher body mass index, and non-smoking. CT antibody testing significantly increased the lifetime prevalence. Combining NAAT outcomes, self-reported positive tests, and antibody testing reduced misclassification in CT prevalence estimates.

Valuing the health states associated with breast cancer screening programmes: A systematic review of economic measures

Policy decisions regarding breast cancer screening and treatment programmes may be misplaced unless the decision process includes the appropriate utilities and disutilities of mammography screening and its sequelae. The objectives of this study were to critically review how economic evaluations have valued the health states associated with breast cancer screening, and appraise the primary evidence informing health state utility values (cardinal measures of quality of life). A systematic review was conducted up to September 2018 of studies that elicited or used utilities relevant to mammography screening. The methods used to elicit utilities and the quality of the reported values were tabulated and analysed narratively. 40 economic evaluations of breast cancer screening programmes and 10 primary studies measuring utilities for health states associated with mammography were reviewed in full. The economic evaluations made different assumptions about the measures used, duration applied and the sequalae included in each health state. 22 evaluations referenced utilities based on assumptions or used measures that were not methodologically appropriate. There was significant heterogeneity in the utilities generated by the 10 primary studies, including the methods and population used to derive them. No study asked women to explicitly consider the risk of overdiagnosis when valuing the health states described. Utilities informing breast screening policy are restricted in their ability to reflect the full benefits and harms. Evaluating the true cost-effectiveness of breast cancer screening will remain problematic, unless the methodological challenges associated with valuing the disutilities of screening are adequately addressed.

Screening for chlamydia and/or gonorrhea in primary health care: protocol for systematic review

BACKGROUND

Chlamydia trachomatis and Neisseria gonorrhoeae are the most commonly reported sexually transmitted infections in Canada. Existing national guidance on screening for these infections was not based on a systematic review, and recommendations as well as implementation considerations (e.g., population groups, testing and case management) should be explicit and reflect the quality of evidence. The aim of this systematic review is to synthesize research on screening for these infections in sexually active individuals within primary care. We will also review evidence on how people weigh the relative importance of the potential outcomes from screening, rated as most important by the Canadian Task Force on Preventive Health Care (CTFPHC) with input from patients and stakeholders.

METHODS

We have developed a peer-reviewed strategy to comprehensively search MEDLINE, Embase, Cochrane Library, CINAHL, and PsycINFO for English and French literature published 1996 onwards. We will also search trial registries and conference proceedings, and mine references lists. Screening, study selection, risk of bias assessments, and quality of findings across studies (for each outcome) will be independently undertaken by two reviewers with consensus for final decisions. Data extraction will be conducted by one reviewer and checked by another for accuracy and completeness. The CTFPHC and content experts will provide input for decisions on study design (i.e., when and whether to include uncontrolled studies for screening effectiveness) and for interpretation of the findings.

DISCUSSION

The results section of the review will include a description of all studies, results of all analyses, including planned subgroup and sensitivity analyses, and evidence profiles and summary of findings tables incorporating assessment based on Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods to communicate our confidence in the estimates of effect. We will compare our findings to others and discuss limitations of the review and available literature. The findings will be used by the CTFPHC-supplemented by consultations with patients and stakeholders and from other sources on issues of feasibility, acceptability, costs/resources, and equity-to inform recommendations on screening to support primary health care providers in delivering preventive care.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42018100733.

A Systematic Review of the Techniques Used to Value Temporary Health States

BACKGROUND

A broad literature on health state utility values exists, but compared with chronic health states (HSs), issues surrounding the valuation of temporary health states (THSs) have been poorly explored.

OBJECTIVES

To assess the methods used by previous studies to value HSs that are considered temporary so as to determine the strengths and limitations associated with various approaches and to inform future study designs.

METHODS

A systematic review was undertaken to explore the methods used, assess how the valuation was conducted for diseases that might lead to HSs deemed as temporary, and identify the challenges encountered in the valuation of THSs.

RESULTS

Of the 36 relevant studies, 22 were explicit that the HS being valued was temporary. Most of the studies used more than one technique (often incorporating both conventional and adapted approaches). In using adapted techniques, the primary challenge was identifying an appropriate intermediate "anchor" HS and the possibility of negative utilities.

CONCLUSIONS

There is no agreement on the most methodologically robust approach to THS valuation. Valuation is complex and important issues relating to the validity, practicality, and reliability of the techniques used were not adequately covered by most of the studies identified.

Using patient values and preferences to inform the importance of health outcomes in practice guideline development following the GRADE approach

Background

There are diverse opinions and confusion about defining and including patient values and preferences (i.e. the importance people place on the health outcomes) in the guideline development processes. This article aims to provide an overview of a process for systematically incorporating values and preferences in guideline development.

Methods

In 2013 and 2014, we followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to adopt, adapt and develop 226 recommendations in 22 guidelines for the Ministry of Health of the Kingdom of Saudi Arabia. To collect context-specific values and preferences for each recommendation, we performed systematic reviews, asked clinical experts to provide feedback according to their clinical experience, and consulted patient representatives.

Results

We found several types of studies addressing the importance of outcomes, including those reporting utilities, non-utility measures of health states based on structured questionnaires or scales, and qualitative studies. Guideline panels used the relative importance of outcomes based on values and preferences to weigh the balance of desirable and undesirable consequences of alternative intervention options. However, we found few studies addressing local values and preferences.

Conclusions

Currently there are different but no firmly established processes for integrating patient values and preferences in healthcare decision-making of practice guideline development. With GRADE Evidence-to-Decision (EtD) frameworks, we provide an empirical strategy to find and incorporate values and preferences in guidelines by performing systematic reviews and eliciting information from guideline panel members and patient representatives. However, more research and practical guidance are needed on how to search for relevant studies and grey literature, assess the certainty of this evidence, and best summarize and present the findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-017-0621-0) contains supplementary material, which is available to authorized users.

Measuring Health and Quality of Life for Women Undergoing Testing and Screening for Chlamydia: A Systematic Review

BACKGROUND

Most economic evaluations of interventions to prevent or control curable sexually transmitted infections (STIs), such as chlamydia, have focused on the longer-term health impacts avoided. However, there is a range of qualitative evidence suggesting that those who think that they might have an STI and/or undergo testing can experience impacts on their quality of life (QoL) at the testing and diagnosis stage. A systematic review was undertaken to identify and evaluate studies that have measured QoL and sexual health for women undergoing testing and screening for chlamydia.

METHODS

A systematic review was conducted, with searches of 5 electronic databases up to the end of August 2013. Data on study characteristics, methods, and results were extracted using a standard template, and a narrative synthesis was undertaken.

RESULTS

Eight studies measuring QoL and sexual health were included. The included studies measured a variety of aspects of QoL and sexual health, with a focus on psychosocial well-being. A range of validated tools were used to measure health and QoL, and "bespoke" questions were also developed. Few significant differences were found with comparator groups using generic instruments, but some impacts were found using bespoke questions.

CONCLUSIONS

Although researchers have begun to examine the relationships between QoL and sexual health, there are limitations associated with the evidence available. There is, thus, a need for further research exploring sexual health and QoL for patients undergoing testing and screening for curable STIs, with a focus on analyzing the most appropriate methodological approaches in this context.

Chlamydia sequelae cost estimates used in current economic evaluations: does one-size-fit-all?

BACKGROUND

Current evidence suggests that chlamydia screening programmes can be cost-effective, conditional on assumptions within mathematical models. We explored differences in cost estimates used in published economic evaluations of chlamydia screening from seven countries (four papers each from UK and the Netherlands, two each from Sweden and Australia, and one each from Ireland, Canada and Denmark).

METHODS

From these studies, we extracted management cost estimates for seven major chlamydia sequelae. In order to compare the influence of different sequelae considered in each paper and their corresponding management costs on the total cost per case of untreated chlamydia, we applied reported unit sequelae management costs considered in each paper to a set of untreated infection to sequela progression probabilities. All costs were adjusted to 2013/2014 Great British Pound (GBP) values.

RESULTS

Sequelae management costs ranged from £171 to £3635 (pelvic inflammatory disease); £953 to £3615 (ectopic pregnancy); £546 to £6752 (tubal factor infertility); £159 to £3341 (chronic pelvic pain); £22 to £1008 (epididymitis); £11 to £1459 (neonatal conjunctivitis) and £433 to £3992 (neonatal pneumonia). Total cost of sequelae per case of untreated chlamydia ranged from £37 to £412.

CONCLUSIONS

There was substantial variation in cost per case of chlamydia sequelae used in published chlamydia screening economic evaluations, which likely arose from different assumptions about disease management pathways and the country perspectives taken. In light of this, when interpreting these studies, the reader should be satisfied that the cost estimates used sufficiently reflect the perspective taken and current disease management for their respective context.

Sexual health promotion for young people delivered via digital media: a scoping review

Background

Young people are at risk of poor sexual health and are, therefore, in need of comprehensive, effective sexual health education. Young people are confident and constant users of digital technology, such as the internet and mobile phones, and there are many innovative possibilities for sexual health education involving these technologies.

Objectives

To summarise evidence on effectiveness, cost-effectiveness and mechanism of action of interactive digital interventions (IDIs) for sexual health; optimal practice for intervention development; contexts for successful implementation; research methods for digital intervention evaluation; and the future potential of sexual health promotion via digital media.

Design

Literature review of evidence on digital interventions for sexual health for young people, integrating the findings with the views of young people, parents and experts in digital media/sexual health. IDIs are defined as digital media programmes that provide health information and tailored decision support, behaviour-change support and/or emotional support. We focus on sexual well-being for young people aged 13–24 years in the UK.

Results

There are many imaginative IDIs for sexual health promotion, but few interventions address issues that are important to young people, such as sexual pleasure and relationships. It is vital to collaborate with young people and to use Behaviour-Change Theory in designing interventions. We located 19 randomised controlled trials of IDIs for sexual health promotion for young people, finding a moderate effect on sexual health knowledge [standardised mean difference (SMD) 0.54, 95% confidence interval (CI) 0.17 to 0.92], a small effect on confidence (self-efficacy) (SMD 0.11, 95% CI 0.02 to 0.20) and a positive effect on sexual behaviour (odds ratio 1.28, 95% CI 1.01 to 1.61), but no significant effects on safer sex intention or biological outcomes. One study suggests that IDIs may be as good as face-to-face interventions for sexual health knowledge and safer sex intention. There are no existing data on the cost-effectiveness of IDIs for sexual health promotion. The impact of an IDI will be determined by the proportion of the target population reached, intervention efficacy, adoption in a setting, how well it is delivered and maintenance/sustainability. All of these elements must be addressed for IDIs to be successful. More collaboration is needed to capitalise on the knowledge of users and stakeholders, the design and software skills of the commercial sector and the theoretical expertise and evaluation skills of academia.

Conclusions

IDIs are effective for knowledge acquisition and sexual behaviour, and could usefully contribute to sexual health education in schools, in clinic settings and online; however, there are obstacles to overcome, such as access to information technology and ensuring the quality and safety of interventions.

Future work

More evidence is needed on the best designs for interventions (e.g. choice of behaviour-change mechanisms and interactive features) and the best models of delivery (e.g. setting, modes of delivery, methods of facilitation and support for engagement) to improve sexual behaviour, biological outcomes and sexual well-being in a cost-effective way.

Funding

The National Institute for Health Research Public Health Research programme.

Conceptualising quality of life outcomes for women participating in testing for sexually transmitted infections: A systematic review and meta-synthesis of qualitative research

Many public health interventions have aims which are broader than health alone; this means that there are difficulties in using outcome measures that capture health effects only, such as Quality Adjusted Life Years (QALYs). Sexually Transmitted Infections (STIs) are a major public health concern both in the UK and globally, with Chlamydia trachomatis being the most common bacterial STI worldwide. There is scope for the wider use of qualitative syntheses in health-related research; in this study we highlight their potential value in informing outcome identification, particularly for public health interventions where a broad range of outcomes may need to be considered. This article presents a systematic review and meta-ethnography of qualitative studies that investigated women's experiences of thinking about and participating in testing for chlamydia. The meta-ethnography highlights issues relating to beliefs about STIs and testing, assessing risk and interpreting symptoms, emotional responses to testing, coping with diagnosis, relationship with sex partners(s), informal support, and interaction with health care services. The study findings suggest that women can experience a range of impacts on their health and quality of life. It is important that this range of effects is taken into account within evaluations, to ensure that decision makers are fully informed about the outcomes associated with screening interventions, and ultimately, to make sure that appropriate interventions are available to support women in maintaining good sexual health.

High-resolution typing of Chlamydia trachomatis: epidemiological and clinical uses

PURPOSE OF REVIEW

A state-of-the-art overview of molecular Chlamydia trachomatis typing methods that are used for routine diagnostics and scientific studies.

RECENT FINDINGS

Molecular epidemiology uses high-resolution typing techniques such as multilocus sequence typing, multilocus variable number of tandem repeats analysis, and whole-genome sequencing to identify strains based on their DNA sequence. These data can be used for cluster, network and phylogenetic analyses, and are used to unveil transmission networks, risk groups, and evolutionary pathways. High-resolution typing of C. trachomatis strains is applied to monitor treatment efficacy and re-infections, and to study the recent emergence of lymphogranuloma venereum (LGV) amongst men who have sex with men in high-income countries. Chlamydia strain typing has clinical relevance in disease management, as LGV needs longer treatment than non-LGV C. trachomatis. It has also led to the discovery of a new variant Chlamydia strain in Sweden, which was not detected by some commercial C. trachomatis diagnostic platforms.

SUMMARY

After a brief history and comparison of the various Chlamydia typing methods, the applications of the current techniques are described and future endeavors to extend scientific understanding are formulated. High-resolution typing will likely help to further unravel the pathophysiological mechanisms behind the wide clinical spectrum of chlamydial disease.

Chlamydia screening is not cost-effective at low participation rates: evidence from a repeated register-based implementation study in The Netherlands

OBJECTIVE

In three pilot regions of The Netherlands, all 16-29 year olds were invited to participate in three annual rounds of Chlamydia screening. The aim of the present study is to evaluate the cost-effectiveness of repeated Chlamydia screening, based on empirical data.

METHODS

A mathematical model was employed to estimate the influence of repeated screening on prevalence and incidence of Chlamydial infection. A model simulating the natural history of Chlamydia was combined with cost and utility data to estimate the number of major outcomes and quality-adjusted life-years (QALYs) associated with Chlamydia. Six screening scenarios (16-29 years annually; 16-24 years annually; women only; biennial screening; biennial screening women only; screening every five years) were compared with no screening in two sexual networks, representing both lower ('national network') and higher ('urban network') baseline prevalence. Incremental cost-effectiveness ratios (ICERs) for the different screening scenarios were estimated. Uncertainty and sensitivity analyses were performed.

RESULTS

In all scenarios and networks, cost per major outcome averted are above €5000. Cost per QALY are at least €50,000. The default scenario as piloted in the Netherlands was least cost-effective, with ICERs of €232,000 in the national and €145,000 in the urban sexual network. Results were robust in sensitivity analyses.

CONCLUSIONS

It is unlikely that repeated rounds of Chlamydia screening will be cost-effective. Only at high levels of willingness to pay for a QALY (>€50,000) screening may be more cost-effective than no screening.

Impact and cost-effectiveness of chlamydia testing in Scotland: a mathematical modelling study

Background

Chlamydia is the most common sexually transmitted bacterial infection in Scotland, and is associated with potentially serious reproductive outcomes, including pelvic inflammatory disease (PID) and tubal factor infertility (TFI) in women. Chlamydia testing in Scotland is currently targeted towards symptomatic individuals, individuals at high risk of existing undetected infection, and young people. The cost-effectiveness of testing and treatment to prevent PID and TFI in Scotland is uncertain.

Methods

A compartmental deterministic dynamic model of chlamydia infection in 15–24 year olds in Scotland was developed. The model was used to estimate the impact of a change in testing strategy from baseline (16.8% overall testing coverage; 0.4 partners notified and tested/treated per treated positive index) on PID and TFI cases. Cost-effectiveness calculations informed by best-available estimates of the quality-adjusted life years (QALYs) lost due to PID and TFI were also performed.

Results

Increasing overall testing coverage by 50% from baseline to 25.2% is estimated to result in 21% fewer cases in young women each year (PID: 703 fewer; TFI: 88 fewer). A 50% decrease to 8.4% would result in 20% more PID (669 additional) and TFI (84 additional) cases occurring annually. The cost per QALY gained of current testing activities compared to no testing is £40,034, which is above the £20,000-£30,000 cost-effectiveness threshold. However, calculations are hampered by lack of reliable data. Any increase in partner notification from baseline would be cost-effective (incremental cost per QALY gained for a partner notification efficacy of 1 compared to baseline: £5,119), and would increase the cost-effectiveness of current testing strategy compared to no testing, with threshold cost-effectiveness reached at a partner notification efficacy of 1.5. However, there is uncertainty in the extent to which partner notification is currently done, and hence the amount by which it could potentially be increased.

Conclusions

Current chlamydia testing strategy in Scotland is not cost-effective under the conservative model assumptions applied. However, with better data enabling some of these assumptions to be relaxed, current coverage could be cost-effective. Meanwhile, increasing partner notification efficacy on its own would be a cost-effective way of preventing PID and TFI from current strategy.

Electronic supplementary material

The online version of this article (doi:10.1186/1742-4682-12-2) contains supplementary material, which is available to authorized users.

Chlamydia trachomatis and Genital Mycoplasmas: Pathogens with an Impact on Human Reproductive Health

The most prevalent, curable sexually important diseases are those caused by Chlamydia trachomatis (C. trachomatis) and genital mycoplasmas. An important characteristic of these infections is their ability to cause long-term sequels in upper genital tract, thus potentially affecting the reproductive health in both sexes. Pelvic inflammatory disease (PID), tubal factor infertility (TFI), and ectopic pregnancy (EP) are well documented complications of C. trachomatis infection in women. The role of genital mycoplasmas in development of PID, TFI, and EP requires further evaluation, but growing evidence supports a significant role for these in the pathogenesis of chorioamnionitis, premature membrane rupture, and preterm labor in pregnant woman. Both C. trachomatis and genital mycoplasmas can affect the quality of sperm and possibly influence the fertility of men. For the purpose of this paper, basic, epidemiologic, clinical, therapeutic, and public health issue of these infections were reviewed and discussed, focusing on their impact on human reproductive health.