Don C. Des Jarlais

Improving the Reporting Quality of Nonrandomized Evaluations of Behavioral and Public Health Interventions: The TREND Statement

Developing an evidence base for making public health decisions will require using data from evaluation studies with randomized and nonrandomized designs. Assessing individual studies and using studies in quantitative research syntheses require transparent reporting of the study, with sufficient detail and clarity to readily see differences and similarities among studies in the same area. The Consolidated Standards of Reporting Trials (CONSORT) statement provides guidelines for transparent reporting of randomized clinical trials. We present the initial version of the Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) statement. These guidelines emphasize the reporting of theories used and descriptions of intervention and comparison conditions, research design, and methods of adjusting for possible biases in evaluation studies that use nonrandomized designs.

Audio-computer interviewing to measure risk behaviour for HIV among injecting drug users: a quasi-randomised trial.

BACKGROUND We aimed to assess audio-computer-assisted self-interviewing (audio-CASI) as a method of reducing under-reporting of HIV risk behaviour among injecting drug users. METHODS Injecting drug users were interviewed at syringe-exchange programmes in four US cities. Potential respondents were randomly selected from participants in the syringe exchanges, with weekly alternate assignment to either traditional face-to-face interviews or audio-CASI. The questionnaire included items on sociodemographic characteristics, drug use, and HIV risk behaviours for 30 days preceding the interview. We calculated odds ratios for the difference in reporting of HIV risk behaviours between interview methods. FINDINGS 757 respondents were interviewed face-to-face, and 724 were interviewed by audio-CASI. More respondents reported HIV risk behaviours and other sensitive behaviours in audio-CASI than in face-to-face interviews (odds ratios for reporting of rented or bought used injection equipment in audio-CASI vs face-to-face interview 2.1 [95% CI 1.4-3.3] p=0.001; for injection with borrowed used injection equipment 1.5 [1.1-2.2] p=0.02; for renting or selling used equipment 2.3 [1.3-4.0] p=0.003). INTERPRETATION Although validation of these self-reported behaviours was not possible, we propose that audio-CASI enables substantially more complete reporting of HIV risk behaviour. More complete reporting might increase understanding of the dynamics of HIV transmission and make the assessment of HIV-prevention efforts easier.

Methadone maintenance treatment in opiate dependence: a review.

This paper examines the changes and advances in research and clinical practice and examines the role of treatment structure and programme characteristics in the delivery of methadone maintenance. Methadone prescribing has become much more available over the past decade, both in countries with a history of its use, such as the United Kingdom and Australia, and in countries around the world which previously had not endorsed substitute prescribing.1 There is a need to examine closely the framework in which this treatment is delivered to ensure that the modes of delivery most effective from both cost and benefit perspectives are utilised. This review focuses entirely on methadone maintenance because this is the most extensively evaluated and most used treatment, with about a quarter of a million drug misusers receiving methadone treatment globally. A small number of experimental diamorphine and buprenorphine substitute programmes are being evaluated in several countries. Most studies have come from the United States and focus on the long term use of methadone in a specific setting; in contrast, methadone treatment in the United Kingdom has received virtually no formal evaluation to date bar one study.2 There is concern that a considerable amount of the methadone prescribing could be having little impact on illicit drug use or risk taking behaviour,3 a recent study of drug users in police custody echoes this.4 The Advisory Council on the Misuse of Drugs has recommended a shift to a more structured approach for delivery of oral methadone maintenance. The organisation and regulation of methadone maintenance treatment varies widely, with explicit guidelines for programme operation in the United States and Australia and a virtual absence of structure and regulation in Britain. It is likely that policy analysts and treatment providers in countries with high levels of regulation and structured programmes …

Sociometric risk networks and risk for HIV infection.

OBJECTIVES This study examined whether networks of drug-injecting and sexual relationships among drug injectors are associated with individual human immunodeficiency virus (HIV) serostatus and with behavioral likelihood of future infection. METHODS A cross-sectional survey of 767 drug injectors in New York City was performed with chain-referral and linking procedures to measure large-scale (sociometric) risk networks. Graph-theoretic algebraic techniques were used to detect 92 connected components (drug injectors linked to each other directly or through others) and a 105-member 2-core within a large connected component of 230 members. RESULTS Drug injectors in the 2-core of the large component were more likely than others to be infected with HIV. Seronegative 2-core members engaged in a wide range of high-risk behaviors, including engaging in risk behaviors with infected drug injectors. CONCLUSIONS Sociometric risk networks seem to be pathways along which HIV travels in drug-injecting peer groups. The cores of large components can be centers of high-risk behaviors and can become pockets of HIV infection. Preventing HIV from reaching the cores of large components may be crucial in preventing widespread HIV epidemics.

Alternatives to the randomized controlled trial

Public health researchers are addressing new research questions (e.g., effects of environmental tobacco smoke, Hurricane Katrina) for which the randomized controlled trial (RCT) may not be a feasible option. Drawing on the potential outcomes framework (Rubin Causal Model) and Campbellian perspectives, we consider alternative research designs that permit relatively strong causal inferences. In randomized encouragement designs, participants are randomly invited to participate in one of the treatment conditions, but are allowed to decide whether to receive treatment. In quantitative assignment designs, treatment is assigned on the basis of a quantitative measure (e.g., need, merit, risk). In observational studies, treatment assignment is unknown and presumed to be nonrandom. Major threats to the validity of each design and statistical strategies for mitigating those threats are presented.

A meta-analysis of the effect of HIV prevention interventions on the sex behaviors of drug users in the United States

Summary: We examined the effectiveness of 33 U.S.‐based HIV intervention studies in reducing the sexual risk behaviors of drug users by reducing unprotected sex or increasing the use of male condoms. The studies, identified as of June 1998, through the HIV/AIDS Prevention Research Synthesis project, were published in 1988 or later, measured behavioral or biologic outcomes, used experimental designs or certain quasiexperimental designs, and reported sufficient data for calculating an effect size for sexual risk reduction. Of the 33 studies, 94% recruited injection drug users; 21% recruited crack users. The mean age of participants was 36 years. Almost all studies were randomized (94%), provided another HIV intervention to the comparison groups (91%), and evaluated behavioral interventions (91%). On average, interventions were conducted in 5 sessions (total, 10 hours) during 4.5 months. Interventions compared with no interventions were strong and significant (k = 3; odds ratio [OR], 0.60; 95% confidence interval [CI], 0.43‐0.85). Interventions compared with other HIV interventions showed a modest additional benefit (k = 30; OR, 0.91; 95% CI, 0.81‐1.03). When we extrapolated our result (an OR of 0.60) to a population with a 72% prevalence of risk behavior, the proportion of drug users who reduced their risk behaviors was 12.6% greater in the intervention groups than in the comparison groups. Our meta‐analysis shows that interventions can lead to sexual risk reduction among drug users and justifies providing interventions to drug users. Developing interventions with stronger effects to further reduce sexual risk behaviors among drug users must remain a high priority.

A randomized trial of an interim methadone maintenance clinic.

BACKGROUND Interim methadone maintenance has been proposed as a method of providing clinically effective services to heroin addicts waiting for treatment in standard comprehensive methadone maintenance programs. METHODS A clinic that provided initial medical evaluation, methadone medication, and AIDS education, but did not include formal drug abuse counseling or other social support services was established in New York City. A sample of 301 volunteer subjects recruited from the waiting list for treatment in the Beth Israel methadone program were randomly assigned to immediate entry into the interim clinic or a control group. RESULTS There were no differences in initial levels of illicit drug use across the experimental and control groups. One-month urinalysis follow-up data showed a significant reduction in heroin use in the experimental group (from 63% positive at intake to 29% positive) with no change in the control group (62% to 60% positive). No significant change was observed in cocaine urinalyses (approximately 70% positive for both groups at intake and follow-up). A higher percentage of the experimental group were in treatment at 16-month follow-up (72% vs 56%). CONCLUSIONS Limited services interim methadone maintenance can reduce heroin use among persons awaiting entry into comprehensive treatment and increase the percentage entering treatment.

Meta-Regression of Hepatitis C Virus Infection in Relation to Time Since Onset of Illicit Drug Injection: The Influence of Time and Place

The authors examined the relation between time since onset of illicit drug injection (time at risk) and rates of hepatitis C virus (HCV) infection by using meta-regression. In 72 prevalence studies, median time since onset of injection was 7.24 years and median prevalence was 66.02%. The model showed statistically significant linear and quadratic effects of time at risk on HCV prevalence and significantly higher prevalence in developing and transitional countries and in earlier samples (1985-1995). In developed countries post-1995, mean fitted prevalence was 32.02% (95% confidence interval: 25.31, 39.58) at 1 year of injection and 53.01% (95% confidence interval: 40.69, 65.09) at 5 years. In developing/transitional countries post-1995, mean fitted HCV prevalence was 59.13% (95% confidence interval: 30.39, 82.74) at 1 year of injection. In 10 incidence studies, median time at risk was 5.29 years and median cumulative HCV incidence was 20.69%. Mean fitted cumulative incidence was 27.63% (95% confidence interval: 16.92, 41.70) at 1 year of drug injection. The authors concluded that time to HCV infection in developed countries has lengthened. More rapid onset of HCV infection in drug injectors in developing/transitional countries resembles an earlier era of the HCV epidemic in other regions.

HIV Incidence Among Injection Drug Users in New York City, 1990 to 2002: Use of Serologic Test Algorithm to Assess Expansion of HIV Prevention Services

OBJECTIVES We sought to estimate HIV incidence among injection drug users (IDUs) in New York City from 1990 to 2002 to assess the impact of an expansion of syringe exchange services. Syringe exchange increased greatly during this period, from 250,000 to 3,000,000 syringes exchanged annually. METHODS Serum samples were obtained from serial cross-sectional surveys of 3,651 IDUs. HIV-positive samples were tested with the Serologic Test Algorithm for Recent HIV Seroconversion (STARHS) assay to identify recent HIV infections and to estimate HIV incidence. Consistency with other incidence studies was used to assess strengths and limitations of STARHS. RESULTS HIV incidence declined from 3.55/100 person-years at risk (PYAR) from 1990-1992, to 2.63/100 PYAR from 1993-1995, to 1.05/100 PYAR from 1996-1998, and to 0.77/100 PYAR from 1999-2002 (P<.001). There was a very strong negative linear relationship (r= -.99, P<.005) between the annual numbers of syringes exchanged and estimated HIV incidence. These results were highly consistent with a large number of shorter incidence studies among IDUs conducted during the time period. CONCLUSIONS STARHS testing of samples from large serial cross-sectional surveys can provide important data for the assessment of community-level HIV prevention.

Hepatitis C virus infection among injection drug users: survival analysis of time to seroconversion.

Background: Time to hepatitis C virus (HCV) seroconversion in initially seronegative injection drug users has not been directly measured, and public health planning would benefit from specifying the window of opportunity for prevention of infection, and factors that affect timing of infection. Methods: Four hundred eighty-four HCV antibody-negative injection drug users in Seattle, Washington were followed a median of 2.1 years to observe seroconversion. We examined time to HCV seroconversion in relation to subject characteristics using the Kaplan-Meier method and Cox proportional hazards regression. A weighted-average time to HCV seroconversion was calculated among new injectors (injecting ≤2 years) using seroprevalence and seroincidence data. Results: There were 134 HCV seroconversions (11.6 per 100 person-years at risk; the 25th percentile of time to seroconversion was 26.2 months). Injection with a syringe used by another injector (adjusted hazards ratio = 1.8; 95% confidence interval = 1.3–3.0) and sharing a cooker or cotton (1.8; 1.0–3.1) were associated with time to HCV seroconversion. Using the estimate of the mean time to seroconversion from first injection in new injectors who were HCV antibody-negative at enrollment (5.4 years), and the midpoint between first injection and study enrollment in new injectors who were HCV antibody-positive at enrollment (0.6 years), the weighted-average time to seroconversion after beginning to inject was estimated to be 3.4 years. Conclusion: The period of susceptibility to HCV infection in the majority of drug injectors appears to be long enough to justify the allocation of substantial resources toward interventions to reduce injection-related risk behavior in these individuals.