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Introduction: Pre-exposure prophylaxis (PrEP) is a key HIV prevention technology, and is a pillar of a comprehensive HIV prevention approach for men who have sex with men (MSM). Because there have been no national data to characterize trends in the PrEP continuum in the United States, overall and for key demographic groups of MSM, we aimed to describe the extent to which PrEP awareness, willingness and use changed over time, overall and for specific groups of MSM critical for HIV prevention (e.g. Black and Hispanic MSM, younger MSM, MSM in rural areas and MSM without health coverage)., Methods: The American Men's Internet Survey (AMIS) is an annual survey of US MSM conducted in the United States among MSM aged ≥15 years since 2013. We analysed data on trends in elements of the PrEP continuum (awareness, willingness and use of PrEP) in a sample of 37,476 HIV-negative/unknown status MSM from December 2013 through November 2017. We evaluated trends in continuum steps overall and among demographic subgroups using Poisson models with Generalized Estimating Equations. For 2017 data, we used logistic regression to compare the prevalence of PrEP use among demographic groups., Results: Overall, 51.4% (n = 19,244) of AMIS respondents were PrEP-eligible across study years. Between 2013 and 2017, PrEP awareness increased from 47.4% to 80.6% willingness to use PrEP increased from 43.9% to 59.5% and PrEP use in the past 12 months increased from 1.7% to 19.9%. In 2017, use of PrEP was lower for men who were younger, lived outside of urban areas, and lacked health insurance; PrEP use was not different among Black, Hispanic and white MSM., Conclusions: Our data show progress in use of PrEP among US MSM, but also reveal mismatches between PrEP use and epidemic need. We call for additional support of PrEP initiation, especially among young, non-urban and uninsured MSM. Black and Hispanic MSM report levels of PrEP use no different from white MSM, but given higher HIV incidence for Black and Hispanic MSM, parity in use is not sufficient for epidemic control or health equity., (© 2020 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

The American Men's Internet Survey (AMIS) is conducted annually with 10,000 men age 15 + who have sex with men (MSM). Modeling was used with 39,863 AMIS surveys from 4 cycles between December 2013 to February 2017 to identify temporal trends in sexual behavior, substance use, and testing behavior (within 12 months preceding interview) stratified by participants' self-reported HIV status. HIV-negative/unknown status MSM had significant increases in condomless anal intercourse (CAI), marijuana use, use of other illicit substances, sexually transmitted infection (STI) diagnoses, and HIV or STI testing (testing only increased among MSM age 25 +). HIV-negative/unknown status MSM had significant decrease in CAI with an HIV-positive or unknown status partner. HIV-positive MSM had significant increases in CAI, methamphetamine use, and STI diagnoses/testing. Although encouraging, the few indicators of improvement in HIV/STI sexual health practices are not consistently seen across sub-groups of MSM and may be counteracted by growing proportions of MSM engaging in CAI and acquiring STIs.

Regular HIV testing enables early identification and treatment of HIV among at-risk men who have sex with men (MSM). Characterizing HIV testing needs for Internet-using MSM informs development of Internet-facilitated testing interventions. In this systematic review we analyze HIV testing patterns among Internet-using MSM in the United States who report, through participation in an online study or survey, their HIV status as negative or unknown and identify demographic or behavioral risk factors associated with testing. We systematically searched multiple electronic databases for relevant English-language articles published between January 1, 2005 and December 16, 2014. Using meta-analysis, we summarized the proportion of Internet-using MSM who had ever tested for HIV and the proportion who tested in the 12 months preceding participation in the online study or survey. We also identified factors predictive of these outcomes using meta-regression and narrative synthesis. Thirty-two studies that enrolled 83,186 MSM met our inclusion criteria. Among the studies reporting data for each outcome, 85 % (95 % CI 82-87 %) of participants had ever tested, and 58 % (95 % CI 53-63 %) had tested in the year preceding enrollment in the study, among those for whom those data were reported. Age over 30 years, at least a college education, use of drugs, and self-identification as being homosexual or gay were associated with ever having tested for HIV. A large majority of Internet-using MSM indicated they had been tested for HIV at some point in the past. A smaller proportion-but still a majority-reported they had been tested within the year preceding study or survey participation. MSM who self-identify as heterosexual or bisexual, are younger, or who use drugs (including non-injection drugs) may be less likely to have ever tested for HIV. The overall findings of our systematic review are encouraging; however, a subpopulation of MSM may benefit from targeted outreach. These findings indicate unmet needs for HIV testing among Internet-using MSM and identify subpopulations that might benefit from targeted outreach, such as provision of HIV self-testing kits.

Although female sex workers are known to be vulnerable to HIV infection, little is known about the epidemiology of HIV infection among this high-risk population in the United States. We systematically identified and critically assessed published studies reporting HIV prevalence among female sex workers in the United States. We searched for and included original English-language articles reporting data on the prevalence of HIV as determined by testing at least 50 females who exchanged sexual practices for money or drugs. We did not apply any restrictions on date of publication. We included 14 studies from 1987 to 2013 that reported HIV prevalence for a total of 3975 adult female sex workers. Only two of the 14 studies were conducted in the last 10 years. The pooled estimate of HIV prevalence was 17.3 % (95 % CI 13.5-21.9 %); however, the prevalence of HIV across individual studies varied considerably (ranging from 0.3 to 32 %) and statistical heterogeneity was substantial (I(2) = 0.89, Q = 123; p < 0.001). Although the variance across the 14 studies was high, prevalence was generally high (10 % or greater in 11 of the 14 included studies). Very few studies have documented the prevalence of HIV among female sex workers in the United States; however, the available evidence does suggest that HIV prevalence among this vulnerable population is high.

From 2010 to 2014, CDC and the Office of Population Affairs at the USDHHS collaborated on the development of clinical recommendations for providing quality family planning services. A high priority was placed on the use of existing scientific evidence in developing the recommendations, in accordance with IOM guidelines for how to develop "trustworthy" clinical practice guidelines. Consequently, a series of systematic reviews were developed using a transparent and reproducible methodology aimed at ensuring that the clinical practice guidelines would be based on evidence collected in the most unbiased manner possible. This article describes the methodology used in conducting these systematic reviews, which occurred from mid-2011 through 2012., (Copyright © 2015. Published by Elsevier Inc.)

Context: This systematic review evaluated the evidence on the impact of contraceptive counseling provided in clinical settings on reproductive health outcomes to provide information to guide national recommendations on quality family planning services., Evidence Acquisition: Multiple databases were searched during 2010-2011 for peer-reviewed articles published in English from January 1985 through February 2011 describing studies that evaluated contraceptive counseling interventions in clinical settings. Studies were excluded if they focused primarily on prevention of HIV or sexually transmitted infections, focused solely on men, or were conducted outside the U.S., Canada, Europe, Australia, or New Zealand., Evidence Synthesis: The initial search identified 12,327 articles, of which 22 studies (from 23 articles) met the inclusion criteria. Six studies examined the impact of contraceptive counseling among adolescents, with four finding a significant positive impact on at least one outcome of interest. Sixteen studies examined the impact of counseling among adults or mixed populations (adults and adolescents), with 11 finding a significant positive impact on at least one outcome of interest., Conclusions: Promising components of contraceptive counseling were identified despite the diversity of interventions and inability to compare the relative effectiveness of one approach versus another. The evidence base would be strengthened by improved documentation of counseling procedures; assessment of intervention implementation and fidelity to put study findings into context; and development and inclusion of more RCTs, studies conducted among general samples of women, and studies with sample sizes sufficient to detect important behavioral outcomes at least 12 months post-intervention., (Published by Elsevier Inc.)

Context: This systematic review evaluated the evidence on the impact of family planning reminder systems-interventions intended to remind patients of behaviors to achieve reproductive health goals (e.g., daily text messages reminding oral contraceptive [OC] users to take a pill)-to provide information to guide national recommendations on quality family planning services., Evidence Acquisition: Multiple databases including PubMed were searched during 2010-2011 for peer-reviewed articles published in English from January 1985 through February 2011 describing studies evaluating reminder systems to improve family planning outcomes. Studies were excluded if they focused primarily on HIV or sexually transmitted infection prevention, focused solely on men, or were conducted outside the U.S., Europe, Australia, or New Zealand., Evidence Synthesis: The initial search identified 16,129 articles, five of which met the inclusion criteria. Three studies examined the impact of OC reminder systems; two found a statistically significant positive impact on correct use. Two studies examined the impact of reminder systems among depot medroxyprogesterone acetate (DMPA) users; one found a statistically significant positive impact on correct use., Conclusions: Although mixed support was found for the effectiveness of reminder system interventions on correct use of OCs and DMPA, the highest-quality evidence yielded null findings. The evidence base would be strengthened by the development of additional studies, especially RCTs, which objectively measure outcomes, examine additional contraceptive methods, and have sufficient sample sizes to detect behavioral outcomes at least 12 months post-intervention., (Published by Elsevier Inc.)

Context: Educational interventions can help increase knowledge of available contraceptive methods, enabling individuals to make informed decisions and use contraception more effectively. This systematic review evaluated contraceptive education interventions to guide national recommendations on quality family planning services., Evidence Acquisition: Three databases (CINAHL, PubMed, and PsycINFO) were searched from 1985 through 2012 for peer-reviewed articles on educational interventions, with supplemental searches conducted through 2015. Primary outcomes were knowledge, participation in and comfort with decision making, and attitudes toward contraception. Secondary outcomes included contraceptive use behaviors and unintended pregnancy., Evidence Synthesis: Database searches in 2011 identified 5,830 articles; 17 met inclusion criteria and were abstracted into evidence tables. Searches in 2012 and 2015 identified four additional studies. Studies used a wide range of tools (decision aids, written materials, audio/videotapes, and interactive games), with and without input from a healthcare provider or educator. Of 15 studies that examined the impact of educational interventions on knowledge, 14 found significant improvement using a range of tools, with and without input from a healthcare provider or educator. Fewer studies evaluated outcomes related to decision making, attitudes toward contraception, contraceptive use behaviors, or unintended pregnancy., Conclusions: Results from this systematic review are consistent with evidence from the broader healthcare field suggesting that a range of educational interventions can increase knowledge. Future studies should assess what aspects of educational interventions are most effective, the extent to which it is necessary to include a healthcare provider or educator, and the extent to which educational interventions can impact behaviors., (Published by Elsevier Inc.)

Background: Men who have sex with men (MSM) are disproportionately affected by human immunodeficiency virus (HIV) and there is evidence that this population is participating in increasingly risky sexual behavior. These changes are occurring in the context of new modes of online social interaction-many MSM now report first meeting their sex partners on the Internet. Better monitoring of key behavioral indicators among MSM requires the use of surveillance strategies that capitalize on these new modes of interaction. Therefore, we developed an annual cross-sectional behavioral survey of MSM in the United States, the American Men's Internet Survey (AMIS)., Objective: The purpose of this paper was to provide a description of AMIS methods. In addition we report on the first cycle of data collection (December 2013 through May 2014; AMIS-2013) on the same key indicators used for national HIV behavioral surveillance., Methods: AMIS-2013 recruited MSM from a variety of websites using banner advertisements or email blasts. Adult men currently residing in the United States were eligible to participate if they had ever had sex with a man. We examined demographic and recruitment characteristics using multivariable regression modeling (P<.05) stratified by the participants' self-reported HIV status., Results: In the AMIS-2013 round, 79,635 persons landed on the study page and 14,899 were eligible, resulting in 10,377 completed surveys from MSM representing every US state. Participants were mainly white, 40 years or older, living in the US South, living in urban areas, and recruited from a general social networking website. Self-reported HIV prevalence was 10.73% (n=1113). Compared to HIV-negative/unknown status participants, HIV-positive participants were more likely to have had anal sex without a condom with any male partner in the past 12 months (72.24% versus 61.24%, respectively; P<.001) and more likely to have had anal sex without a condom with their last male sex partner who was discordant/unknown HIV status (42.95% versus 13.62%, respectively; P<.001). Illicit substance use in the past 12 months was more likely to be reported by HIV-positive participants than HIV-negative/unknown status participants (39.17% versus 26.85%, respectively; P<.001). The vast majority of HIV-negative/unknown status participants (84.05%) had been previously HIV tested, but less than half (44.20%) had been tested in the past 12 months. Participants 18-24 years of age were more likely than those 40 years or older to have had anal sex without a condom with a discordant/unknown HIV status partner, were more likely to report substance use, and were less likely to have been HIV tested. Compared to general social networking, those from a geospatial social networking website were more likely to have reported all risk behaviors but were more likely to have been HIV tested., Conclusions: The first round of AMIS generated useful behavioral measures from more than 10,000 MSM Internet users. Preliminary findings identified some subgroups of MSM Internet users that are at potentially higher risk of HIV acquisition/transmission. AMIS will provide an ongoing data source for examining trends in sexual risk behavior of MSM. This will help to plan and monitor the impact of programs to improve this population's health.

Increased efforts in comparative effectiveness research (CER) (comparing various health care intervention and treatment options) are being used to inform health care delivery. While CER research itself is an important step in developing best practices in health care, it is not enough to ensure success. The knowledge must also be successfully disseminated to increase adoption and implementation of practices. To ensure the greatest benefits of successful interventions, it is essential to understand which dissemination strategies are effective and under what conditions. This article provides the background and methodology used in a large-scale, 2-year study aimed at determining how knowledge gained from CER research may be most effectively disseminated to those responsible for delivering behavioral health services. The study takes an important step toward addressing the gaps in dissemination and translation of CER.

This randomized controlled trial examined the influence of two strategies (informational packets alone and in conjunction with Webinars) aimed at increasing the adoption of motivational interviewing (MI), a patient-centered behavioral health practice supported by evidence from comparative effectiveness studies, among community health organizations responsible for delivering mental and behavioral health services. Data were obtained from 311 directors and staff across 92 community organizations. Hierarchical linear modeling was used to examine changes in decision to adopt MI. The mediating effects of multiple contextual variables were also examined. Results showed that both strategies positively influenced the decision to adopt. The positive impact on decision to adopt was significantly greater among individuals that received informational packets in conjunction with Webinars. Baseline attitudes toward evidence-based practices and pressures for change appeared to mediate this effect.

Introduction: Whether routine screening for depression among nonpregnant women of reproductive age improves identification and treatment of the disorder remains unclear. We conducted a systematic review of the literature to address 5 key questions specific to this population: 1) What are the current national clinical practice recommendations and guidelines for depression screening; 2) What are the prevalence and predictors of screening; 3) How well do screening tools detect depression; 4) Does screening lead to diagnosis, treatment, and improved outcomes; and 5) What are the most effective treatment methods?, Methods: We searched bibliographic databases for full-length articles published in English between 1990 and 2010 that addressed at least 1 of our key questions., Results: We identified 5 clinical practice guidelines pertinent to question 1, and 12 systematic reviews or post-hoc analyses of pooled data that addressed questions 3 through 5. No systematic reviews addressed question 2; however, we identified 4 individual studies addressing this question. Current guidelines do not recommend universal screening for depression in adults, unless staff supports are in place to diagnose, treat, and follow up patients. Reported screening rates ranged from 33% to 84% among women. Several validated screening tools for depression exist; however, their performance among this population is unknown. Screening in high-risk populations may improve the patient's receipt of diagnosis and treatment. Effective treatments include exercise, psychotherapy, and pharmacotherapy., Conclusion: More research is needed on whether routine screening for depression among women of reproductive age increases diagnosis and treatment of depression, improves preconception health, and reduces adverse outcomes.

Introduction: Hypertension and dyslipidemia often precede cardiovascular disease. Lifestyle modifications help prevent these conditions, and referrals for women may be possible during reproductive health care visits. However, screening recommendations vary, which may affect screening rates. The objectives of this systematic review were to 1) assess the available literature on the effectiveness of lifestyle interventions, 2) review hypertension and dyslipidemia screening recommendations for consistency, and 3) report prevalence data for hypertension and dyslipidemia screening among women of reproductive age., Methods: We conducted a systematic literature search (January 1990-November 2010) for 1) randomized controlled trials on the impact of lifestyle interventions on cardiovascular disease risk factors in women of reproductive age, 2) evidence-based guidelines on hypertension and dyslipidemia screening, and 3) population-based prevalence studies on hypertension or dyslipidemia screening or both., Results: Twenty-one of 555 retrieved studies (4%) met our inclusion criteria. Lifestyle interventions improved lipid levels in 10 of 18 studies and blood pressure in 4 of 9 studies. Most guidelines recommended hypertension screening at least every 2 years and dyslipidemia screening every 5 years, but recommendations for who should receive dyslipidemia screening varied. One study indicated that 82% of women of reproductive age received hypertension screening during the preceding year. In another study, only 49% of women aged 20 to 45 years received recommended dyslipidemia screening., Conclusion: Lifestyle interventions may offer modest benefits for reducing blood pressure and lipids in this population. Inconsistency among recommendations for dyslipidemia screening may contribute to low screening rates. Future studies should clarify predictors of and barriers to cholesterol screening in this population.

Context: Obstructive sleep apnea (OSA) is associated with an increased risk of motor vehicle crash., Objective: We performed a systematic review of the literature concerning the impact of continuous positive airway pressure (CPAP) treatment on motor vehicle crash risk among drivers with OSA. The primary objective was to determine whether CPAP use could reduce the risk of motor vehicle crash among drivers with OSA. A secondary objective involved determining the time on treatment required for CPAP to improve driver safety., Data Sources: We searched seven electronic databases (MEDLINE, PubMed (PreMEDLINE), EMBASE, PsycINFO, CINAHL, TRIS, and the Cochrane library) and the reference lists of all obtained articles., Study Selection: We included studies (before-after, case-control, or cohort) that addressed the stated objectives. We evaluated the quality of each study and the interplay between the quality, quantity, robustness, and consistency of the evidence. We also tested for publication bias., Data Extraction: Data were extracted by two independent analysts. When appropriate, data were combined in a fixed or random effects meta-analysis., Results: A meta-analysis of 9 observational studies examining crash risk of drivers with OSA pre- vs. post-CPAP found a significant risk reduction following treatment (risk ratio = 0.278, 95% CI: 0.22 to 0.35; P < 0.001). Although crash data are not available to assess the time course of change, daytime sleepiness improves significantly following a single night of treatment, and simulated driving performance improves significantly within 2 to 7 days of CPAP treatment., Conclusions: Observational studies indicate that CPAP reduces motor vehicle crash risk among drivers with OSA.

Background: Opioid therapy for chronic noncancer pain (CNCP) is controversial due to concerns regarding long-term effectiveness and safety, particularly the risk of tolerance, dependence, or abuse., Objectives: To assess safety, efficacy, and effectiveness of opioids taken long-term for CNCP., Search Strategy: We searched 10 bibliographic databases up to May 2009., Selection Criteria: We searched for studies that: collected efficacy data on participants after at least 6 months of treatment; were full-text articles; did not include redundant data; were prospective; enrolled at least 10 participants; reported data of participants who had CNCP. Randomized controlled trials (RCTs) and pre-post case-series studies were included., Data Collection and Analysis: Two review authors independently extracted safety and effectiveness data and settled discrepancies by consensus. We used random-effects meta-analysis' to summarize data where appropriate, used the I(2) statistic to quantify heterogeneity, and, where appropriate, explored heterogeneity using meta-regression. Several sensitivity analyses were performed to test the robustness of the results., Main Results: We reviewed 26 studies with 27 treatment groups that enrolled a total of 4893 participants. Twenty five of the studies were case series or uncontrolled long-term trial continuations, the other was an RCT comparing two opioids. Opioids were administered orally (number of study treatments groups [abbreviated as "k"] = 12, n = 3040), transdermally (k = 5, n = 1628), or intrathecally (k = 10, n = 231). Many participants discontinued due to adverse effects (oral: 22.9% [95% confidence interval (CI): 15.3% to 32.8%]; transdermal: 12.1% [95% CI: 4.9% to 27.0%]; intrathecal: 8.9% [95% CI: 4.0% to 26.1%]); or insufficient pain relief (oral: 10.3% [95% CI: 7.6% to 13.9%]; intrathecal: 7.6% [95% CI: 3.7% to 14.8%]; transdermal: 5.8% [95% CI: 4.2% to 7.9%]). Signs of opioid addiction were reported in 0.27% of participants in the studies that reported that outcome. All three modes of administration were associated with clinically significant reductions in pain, but the amount of pain relief varied among studies. Findings regarding quality of life and functional status were inconclusive due to an insufficient quantity of evidence for oral administration studies and inconclusive statistical findings for transdermal and intrathecal administration studies., Authors' Conclusions: Many patients discontinue long-term opioid therapy (especially oral opioids) due to adverse events or insufficient pain relief; however, weak evidence suggests that patients who are able to continue opioids long-term experience clinically significant pain relief. Whether quality of life or functioning improves is inconclusive. Many minor adverse events (like nausea and headache) occurred, but serious adverse events, including iatrogenic opioid addiction, were rare.

Study Objectives: We performed a systematic review of the OSA-related risk of crash in commercial motor vehicle (CMV) drivers. The primary objective involved determining whether individuals with obstructive sleep apnea (OSA) are at an increased risk for a motor vehicle crash when compared to comparable individuals who do not have the disorder. A secondary objective involved determining what factors are associated with an increased motor vehicle crash risk among individuals with OSA., Design/setting: Seven electronic databases (MEDLINE, PubMed (PreMEDLINE), EMBASE, PsycINFO, CINAHL, TRIS, and the Cochrane library) were searched (through May 27, 2009), as well as the reference lists of all obtained articles. We included controlled studies (case-control or cohort) that evaluated crash risk in individuals with OSA. We evaluated the quality of each study and the interplay between the quality, quantity, robustness, and consistency of the body of evidence, and tested for publication bias. Data were extracted by 2 independent analysts. When appropriate, data from different studies were combined in a fixed- or random-effects meta-analysis., Results: Individuals with OSA are clearly at increased risk for crash. The mean crash-rate ratio associated with OSA is likely to fall within the range of 1.21 to 4.89. Characteristics that may predict crash in drivers with OSA include BMI, apnea plus hypopnea index, oxygen saturation, and possibly daytime sleepiness., Conclusions: Untreated sleep apnea is a significant contributor to motor vehicle crashes.

Opioid therapy for chronic noncancer pain (CNCP) is controversial due to concerns regarding long-term efficacy and adverse events (including addiction). We systematically reviewed the clinical evidence on patients treated with opioids for CNCP for at least six months. Of 115 studies identified by our search of eleven databases (through April 7, 2007), 17 studies (patients [n]=3,079) met inclusion criteria. Studies evaluated oral (studies [k]=7; n=1,504), transdermal (k=3; n=1, 993), and/or intrathecal (k=8; n=177) opioids. Many patients withdrew from the clinical trials due to adverse effects (oral: 32.5% [95% confidence interval (CI), 26.1%-39.6%]; intrathecal: 6.3% [95% CI, 2.9%-13.1%]; transdermal: 17.5% [95% CI, 6.5%-39.0%]), or due to insufficient pain relief (oral: 11.9% [95% CI, 7.8%-17.7%]; intrathecal: 10.5% [95% CI, 3.5%-27.4%]; transdermal: 5.8% [95% CI, 4.2%-7.3%]). Signs of opioid addiction were reported in only 0.05% (1/2,042) of patients and abuse in only 0.43% (3/685). There was an insufficient amount of data on transdermal opioids to quantify pain relief. For patients able to remain on oral or intrathecal opioids for at least six months, pain scores were reduced long-term (oral: standardized mean difference [SMD] 1.99, 95% CI, 1.17-2.80; intrathecal: SMD 1.33, 95% CI, 0.97-1.69). We conclude that many patients discontinue long-term opioid therapy due to adverse events or insufficient pain relief; however, weak evidence suggests that oral and intrathecal opioids reduce pain long-term in the relatively small proportion of individuals with CNCP who continue treatment.

Background: Methods for describing one's confidence in the available evidence are useful for end-users of evidence reviews. Analysts inevitably make judgments about the quality, quantity consistency, robustness, and magnitude of effects observed in the studies identified. The subjectivity of these judgments in several areas underscores the need for transparency in judgments., Discussion: This paper introduces a new system for rating medical evidence. The system requires explicit judgments and provides explicit rules for balancing these judgments. Unlike other systems for rating the strength of evidence, our system draws a distinction between two types of conclusions: quantitative and qualitative. A quantitative conclusion addresses the question, "How well does it work?", whereas a qualitative conclusion addresses the question, "Does it work?" In our system, quantitative conclusions are tied to stability ratings, and qualitative conclusions are tied to strength ratings. Our system emphasizes extensive a priori criteria for judgments to reduce the potential for bias. Further, the system makes explicit the impact of heterogeneity testing, meta-analysis, and sensitivity analyses on evidence ratings. This article provides details of our system, including graphical depictions of how the numerous judgments that an analyst makes can be combined. We also describe two worked examples of how the system can be applied to both interventional and diagnostic technologies., Summary: Although explicit judgments and formal combination rules are two important steps on the path to a comprehensive system for rating medical evidence, many additional steps must also be taken. Foremost among these are the distinction between quantitative and qualitative conclusions, an extensive set of a priori criteria for making judgments, and the direct impact of analytic results on evidence ratings. These attributes form the basis for a logically consistent system that can improve the usefulness of evidence reviews.

Background: Uncertainty continues to surround the relative benefits and harms of conventional coronary artery bypass grafting (CABG) and off-pump coronary artery bypass grafting (OPCABG). Possible reasons are that high-quality studies have not comprehensively examined relevant patient outcomes and have enrolled a limited range of patients. Some studies may have been too small to detect clinically important differences in patient outcomes. The present study addresses these issues using meta-analysis., Methods: We comprehensively retrieved randomized and nonrandomized controlled studies according to predetermined criteria. We performed meta-analyses for each outcome and empirically determined whether potential biases that might result from differences in study design or patient characteristics actually biased a study's results. We also conducted sensitivity analyses and tested for publication bias., Results: Rates of perioperative myocardial infarction, stroke, reoperation for bleeding, renal failure, and mortality were lower after OPCABG than after CABG. Reductions in length of hospital stay, atrial fibrillation, and wound infection were also associated with OPCABG, but statistically significant differences among study results for these outcomes could not be explained by available information. Midterm (3 to 25 months) angina recurrence did not appear to differ between treatments; a trend was noticed toward lower reintervention rates with CABG, and a trend toward lower overall mortality with OPCABG, at least when performed at experienced centers. These midterm outcome results require confirmation., Conclusions: Off-pump coronary artery bypass grafting appears to reduce length of hospital stay, operative morbidity, and operative mortality relative to on-pump CABG. More studies are required before firm conclusions can be drawn concerning the effect of OPCABG on midterm mortality, angina recurrence, and repeat intervention.