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J G Kahn

Publications and source records attributed to J G Kahn.

33 records · Page 2Linked to original sources

The cost-effectiveness of HIV prevention targeting: how much more bang for the buck?

BACKGROUND: Although the targeting of human immunodeficiency virus (HIV) prevention to high-risk populations has been widely discussed, its benefits have not been quantified. METHODS: This analysis of cost-effectiveness combines an HIV epidemic model, target population scenarios, and data on the cost and impact of prevention. RESULTS: The number of HIV infections averted in 5 years with $1 million in annual prevention spending ranges from 164 in high-risk populations to 0.4 in very-low-risk populations. Fortyfold to two-hundredfold differences in prevention costs could equalize HIV infections averted. CONCLUSIONS: Targeting appears to provide substantial benefit and should be considered in allocation decisions about prevention.

Cost-Benefit Analysis↗

Deferral of blood donors with risk factors for HIV infection saves lives and money in Zimbabwe.

We compared the cost-effectiveness of three strategies to avert transfusion-associated HIV infection in Zimbabwe: HIV antibody testing, deferral of donors with HIV risk factors, and deferral of donors with risk factors followed by antibody testing ("Defer/Test"). The Defer/Test strategy averted the most HIV infections. Compared with antibody testing alone, the Defer/Test strategy, using history of genital ulcer or any sexually transmitted disease as a criterion for deferral, resulted in net savings. The cost per HIV-infected unit averted using history of paying for sex or having had multiple sex partners was $ 127 and $ 773, respectively. We discern four benefits of risk factor-based deferral before antibody testing. First, deferring donors at risk lessens collection of blood in the window period. Second, deferring donors likely to be HIV positive minimizes the number of units discarded. Third, ascertainment of donor risk provides an opportunity for AIDS education and prevention. Fourth, the number of false negatives is lower with a lower HIV prevalence among accepted donors. The Defer/Test strategy is cost-effective in Zimbabwe because additional recruitment costs are offset by discarding fewer HIV-positive units. We predict the Defer/Test strategy will be cost-effective in other sub-Saharan African donor populations.

Blood Donors↗

Avoiding missed opportunities for immunization in the Central African Republic: potential impact on vaccination coverage.

Quantified in the study are the extent of missed opportunities for immunization and the potential increases in vaccination coverage and timeliness that could be achieved by using all health centre visits to administer childhood vaccinations in the Central African Republic. The data were collected during a national vaccination coverage survey of 642 children aged 12-23 months from three areas: rural, urban, and the capital, Bangui. Dates of all vaccination visits and other health centre visits were obtained from combined vaccination/health cards. Nationwide, 70% of all opportunities for valid measles vaccination were missed. Of these, 28% occurred at visits when at least one vaccine was given, while 72% occurred at other health centre visits. If there had been no missed opportunities to administer all vaccinations due when at least one vaccine was given, the coverage would have increased from 53% to 67% for the diphtheria-pertussis-tetanus series, from 54% to 70% for measles, and from 34% to 59% for all antigens. If there had been no missed opportunities at any visit, the corresponding increases would have been to 70%, 76%, and 65%. For measles, 46% of the potential increase depends on recognizing that an earlier dose of the vaccine was invalid and on revaccinating. Days-at-risk for measles (after the age of 270 days) would have been reduced by a mean of 74 days per subject with a health card had no opportunities been missed. The method used serves as a valuable adjunct to evaluations of missed opportunities based on exit interviews at health facilities.(ABSTRACT TRUNCATED AT 250 WORDS)

Central African Republic↗

The cost-effectiveness of voluntary counseling and testing of hospital inpatients for HIV infection.

OBJECTIVE: To evaluate the cost-effectiveness of voluntary counseling and testing of US hospital inpatients for the human immunodeficiency virus (HIV). DATA SOURCES: Data for entry into the model were derived from a review of the literature, consultation with experts, and consensus of the authors. DATA EXTRACTION: We rated our confidence in these probabilities and costs by grading the data inputs using methods adapted from those of the US Preventive Services Task Force. DATA SYNTHESIS: Decision analysis models were developed to evaluate two outcomes: (1) cost per health care worker (HCW) HIV infection averted if measures are taken by the HCW to reduce his or her risk of acquiring HIV; and (2) cost per inpatient HIV infection detected. Sensitivity analyses were also conducted. Using baseline input values, testing to avert HCW infection may prevent 3.6 HIV infections per year at a total program cost of $2.7 billion, or a cost of $753 million per infection averted. At baseline assumptions (seroprevalence = 1%), testing to detect inpatient HIV infection would cost $16,104 per year per infection detected. Cost-effectiveness at baseline drops to $8353 per HIV infection detected if the seroprevalence is 10%. If testing is limited to hospitals with inpatient seroprevalences of at least 1%, approximately 5400 persons per year will be falsely labeled HIV-positive. CONCLUSIONS: This analysis provides no justification for testing inpatients to prevent HIV infection of HCWs. Screening inpatients to detect HIV infection may be justified at seroprevalences exceeding 1%, but issues of medical or social discrimination, false-positive results, informed consent, and logistics must be resolved first.

AIDS Serodiagnosis↗

The cost-effectiveness of HIV testing of physicians and dentists in the United States.

OBJECTIVE: To evaluate the cost-effectiveness of alternative policies for human immunodeficiency testing (HIV) testing of physicians and dentists. METHODS: Decision analysis and cost-effectiveness analysis from a societal perspective were used. Data were derived from extensive literature review and consultation with experts. We conducted sensitivity analyses and also performed a cost-benefit analysis. ANALYSES: We analyzed policies for mandatory or voluntary testing of all physicians, surgeons, and dentists; for those testing positive, we analyzed mandatory or voluntary exclusion from practice, restriction from performance of invasive procedures, or requirements to inform patients of serostatus. MAIN OUTCOME MEASURE: Cost per patient infection averted. RESULTS: Although one-time mandatory testing of surgeons and dentists with mandatory restriction of those found to be HIV-positive is more cost-effective than other policies, the cost-effectiveness varies tremendously under different scenarios. Results were highly sensitive to several data inputs, especially HIV seroprevalence of surgeons and dentists and transmission risk. For example, under a medium seroprevalence and transmission risk scenario, mandatory testing of all surgeons might avert 25 infections at a total cost of $27.9 million or $1,115,000 per infection averted and an incremental cost of $291,000 compared with current testing; however, the incremental cost-effectiveness per patient infection averted ranges from $29,807,000 under a low-risk scenario to a savings of $81,000 under a high-risk scenario. CONCLUSION: Our analysis neither justifies nor precludes a mandatory testing policy. Further research on the key data inputs is needed. Given the ethical, social, and public health implications, mandatory testing policies should not be implemented without greater certainty as to their cost-effectiveness.

AIDS Serodiagnosis↗

Pelvic inflammatory disease: metaanalysis of antimicrobial regimen efficacy.

An extensive body of literature has investigated the efficacy of antimicrobial regimens used to treat pelvic inflammatory disease (PID), leaving many clinicians confused about how to choose among them. This study provides a formal appraisal of these reports. Thirty-four treatment studies published between 1966 and 1992 were identified, using Medline and bibliographies, and evaluated qualitatively and quantitatively in a metaanalysis. Twenty-one studies met the criteria for inclusion in this evaluation: appropriate system for making the diagnosis of PID, standardized assessment of clinical outcome, and entry and follow-up evaluation for lower genital tract infection with Neisseria gonorrhoeae and Chlamydia trachomatis. This metaanalysis identifies a considerable range of quality in study methods and research design and underscores the limitations inherent in comparing such data. Despite this, a number of antimicrobial regimens appear to have very good short-term clinical and microbiologic efficacy. Pooled clinical cure rates range from 75% to 94% and pooled microbiologic cure rates range from 71% to 100%. A cost comparison is provided, and future research priorities are suggested.

Adolescent↗

Diagnosing pelvic inflammatory disease. A comprehensive analysis and considerations for developing a new model.

OBJECTIVE: --To examine the accuracy of existing diagnostic indicators for pelvic inflammatory disease and to develop guidelines for a new diagnostic model. DATA SOURCES: --Studies were identified for the period 1969 through 1990. A Medline search of the English-language literature was conducted using the subject terms pelvic inflammatory disease or salpingitis and diagnosis. In addition, abstracts and bibliographies of articles and books were reviewed. STUDY SELECTION: --Studies were selected if pelvic inflammatory disease was diagnosed using laparoscopic findings or narrow clinical rules. Of the 15 reports identified, 12 were included in this analysis. The selected studies were grouped by a quality rating based on subject selection, definition of pelvic inflammatory disease, data analysis, and other measures. DATA EXTRACTION: --Diagnostic findings were divided into four categories: historical (symptoms), clinical examination (signs), laboratory, and combinations of the above. Sensitivity and specificity were extracted using raw data. Data were classified by quality rating. DATA SYNTHESIS: --Historical findings were usually not statistically significant predictors of pelvic inflammatory disease, and when they were they tended toward low sensitivity and high specificity, while clinical findings were somewhat more sensitive and about as specific. Several laboratory tests showed consistent value in pelvic inflammatory disease diagnosis, with high sensitivity and specificity. Combinations of indicators permitted high sensitivity or high specificity but not both simultaneously. CONCLUSIONS: --No single or combination diagnostic indicator was found to reliably predict pelvic inflammatory disease. Combining published evidence with practical clinical considerations, a diagnostic approach is proposed that emphasizes diagnostic sensitivity when clinical presentation is mild and more thorough evaluation when a woman is severely ill. Research is needed to evaluate the accuracy and acceptability of specific diagnostic models and to investigate new diagnostic indicators.

Female↗

Pelvic inflammatory disease. Key treatment issues and options.

OBJECTIVE: --To examine available data regarding optimal antimicrobial therapy for pelvic inflammatory disease (PID) and to address selected treatment issues confronting clinicians caring for women with PID. DATA SOURCES: --Studies evaluated to help establish the Centers for Disease Control's 1989 Sexually Transmitted Diseases Treatment Guidelines and other reports published since 1985. A MEDLINE search of English-language literature was conducted using the indexing terms "pelvic inflammatory disease" or "pelvic infections" or "salpingitis" and "treatment". In addition, abstracts and bibliographies of articles and books were reviewed. STUDY SELECTION: --Studies were selected for detailed review if they evaluated the effectiveness of an antimicrobial regimen for treatment of PID. DATA EXTRACTION: --All studies were evaluated to determine the numbers of women treated and the percentage with clinical or microbiologic evidence of cure. DATA SYNTHESIS: --A variety of combination antimicrobial regimens are highly effective in providing clinical and microbiologic evidence of cure; few data are available to assess optimal therapy for prevention of late sequelae. Because PID is polymicrobial in cause, recommended antimicrobial regimens are broad-spectrum in coverage. CONCLUSIONS: --No single agent that provides sufficient coverage is currently available. Several combination regimens appear highly effective clinically even among women with tubo-ovarian abscess formation. Uncertainties regarding the effectiveness of antimicrobial therapy for prevention of late sequelae complicate decisions regarding the choice among regimens and the appropriateness of ambulatory treatment of women with PID. Pending better data, hospitalization should be strongly considered, where feasible, particularly for those women with PID desiring further childbearing. Sex partners of all women with PID should be treated.

Anti-Bacterial Agents↗

Crack, sex, and STD.

Increasing rates of syphilis, gonorrhea, chancroid, and sexually transmitted human immunodeficiency virus infection appear to be related to crack cocaine use. This article critically reviews 16 epidemiologic studies that examine drug use, sexual behavior, and sexually transmitted disease (STD). Eight studies found an association between crack and STD, one study found no association between crack and STD, and seven studies found STD to be related to other drugs or methods of cocaine use. The exchange of sex for money or drugs was associated with STD in seven studies. Publications that were reviewed have numerous methodologic weaknesses: broader sampling, uninfected comparison groups, and greater specification of drug use and sexual risk behaviors are needed. Further research should compare different drugs and associated sexual behavior and STD to assess the unique risk conferred by crack. Designing effective interventions will require investigation of risk behavior determinants and barriers to health care.

Chancroid↗

Pregnancies averted among U.S. teenagers by the use of contraceptives.

CONTEXT: The personal and social costs associated with teenage pregnancy in the United States concern many policymakers and researchers, yet the role of contraception in preventing these pregnancies has not been adequately quantified. METHODS: Published estimates of contraceptive effectiveness were applied to 1995 National Survey of Family Growth data on sexual and contraceptive practices in order to estimate the number of pregnancies averted through the use of contraceptives by U.S. teenagers. Four scenarios of contraceptives access--from current levels of access to highly restricted access--and teenagers' sexual and contraceptive practices in response to such restrictions are used to project the potential impact on pregnancies among teenagers. RESULTS: Current levels of contraceptive use averted an estimated 1.65 million pregnancies among 15-19-year-old women in the United States during 1995. If these young women had been denied access to both prescription and over-the-counter contraceptive methods, an estimated one million additional pregnancies (ranging from 750,000 to 1.25 million) would have occurred, assuming some decrease in sexual activity. These pregnancies would have led to 480,000 live births, 390,000 abortions, 120,000 miscarriages, 10,000 ectopic pregnancies and 37 maternal deaths. CONCLUSIONS: Contraceptive use by teenage women prevents pregnancies and negative pregnancy-related health consequences that can disrupt the lives of adolescent women and that have substantial societal costs. Continued and expanded access to contraceptives for adolescents is a critically important public health strategy.

Adolescent↗

Cost and efficiency of HIV voluntary counselling and testing centres in Andhra Pradesh, India.

BACKGROUND: [corrected] As part of the effort to control HIV/AIDS, the number of HlV voluntarycounselling and testingcentres (VCTCs) is increasing rapidly in the public health system of the Indian state of Andhra Pradesh, which is estimated to have one of the highest rates of HIV infection in India. However, systematic data on the cost and efficiency of providing VCT services in India are not available to help guide efficient use of resources for these services. METHODS: We used standardized methods to obtain detailed cost and output data for the 2002-03 fiscal year from written records and interviews in 17 VCTCs in the public health system in Andhra Pradesh. We calculated the economic cost per client receiving VCT services, and analysed the variation and determinants of total and unit costs across VCTCs. We used multivariate regression techniques to estimate incremental unit costs. We assessed hurdles towards serving an optimal number of clients by VCTCs. RESULTS: In the 2002-03 fiscal year, 32 413 clients received the complete sequence of services at the 17 VCTCs, including post-HIV test counselling. The number of clients served by each VCTC ranged from 334 to 7802 (median 979). The overall HIV-positive rate in post-test counselled clients was 20.5% (range 5.4%-52.6%). The cost per client for the complete VCT sequence varied 6-fold between VCTCs (range Rs 141.5-829.6 [US 2.92-17.14 dollars], median Rs 363.5 [US 7.51 dollars]). The cost per client was significantly lower at VCTCs with more clients (p < 0.001, R2 = 0.83; power function) due to substantial fixed costs. Personnel made up the largest component of cost (53.7%). The cost per client had a significant direct relation with percent personnel cost for VCTCs (p < 0.001, R2 = 0.58; exponential function). A multiple regression model revealed that the incremental cost of providing complete VCT services to each HIV-positive and -negative client was Rs 123.5 (US 2.54 dollars) and Rs 59.2 (US 1.22 dollars), respectively. Fourteen VCTCs (82.4%) reported that they could serve more clients with the available personnel and infrastructure, and that inadequate demand for their services was the main hurdle towards achieving this. CONCLUSION: These data suggest that the efforts of the National AIDS Control Organisation of India and the Andhra Pradesh State AIDS Control Society in increasing VCTCs could yield even higher benefit if the demand for these services was enhanced, as this would increase the number of clients served and reduce the cost per client. Ongoing systematic cost-efficiency analysis is necessary to help guide efficient use of HIV-control resources in India.

AIDS Serodiagnosis↗