• U.S. Preventive Services Task Force (USPSTF). Screening for illicit drug use: U.S. Preventive Services Task Force recommendation statement. Rockville (MD): Agency for Healthcare Research and Quality (AHRQ); 2008 Jan. 7 p. [15 references]

This is the current release of the guideline.

This version updates a previously published guideline: U.S. Preventive Services Task Force. Guide to clinical preventive services. 2nd ed. Baltimore (MD): Williams & Wilkins; 1996. Chapter 53, Screening for drug abuse. p. 583-95. [80 references]

Illicit drug use

Prevention
Screening

Family Practice
Internal Medicine
Nursing
Obstetrics and Gynecology
Pediatrics
Preventive Medicine

Advanced Practice Nurses
Allied Health Personnel
Health Care Providers
Nurses
Physician Assistants
Physicians

• To summarize the U.S. Preventive Services Task Force (USPSTF) recommendations and supporting scientific evidence on screening for illicit drug use
• To update the 1996 USPSTF recommendations on screening for illicit drug use

Asymptomatic adolescents, adults, and pregnant women

Note: The following was considered but not recommended:

Routine screening for illicit drug use using standardized questionnaires or toxicologic tests of blood or urine

Key Question 1: Is there direct evidence that screening for drug misuse reduces morbidity and/or mortality?

Key Question 2: Do screening tests accurately detect drug misuse?

Key Question 3: Does screening for drug misuse result in adverse effects?

Key Question 4: Does treatment for drug misuse among individuals identified through screening improve morbidity and/or mortality?

Key Question 5: Does treatment for drug misuse among individuals identified through screening result in decreased drug misuse?

Key Question 5a: Does treatment for drug misuse reduce risk behaviors or improve social and legal outcomes?

Key Question 6: Does treatment for drug misuse result in adverse effects?

Key Question 7: Is decreased use or abstinence following drug misuse reliably associated with reduced morbidity and mortality?

Searches of Electronic Databases

Staged Systematic Review

Key Question 1: No relevant articles were identified.

Key Questions 4, 5, and 5a: 17 relevant articles were identified.

Key Question 7: 11 relevant articles were identified.

Supplemental Review: Assessment of Screening Instruments

The abstracts of a total of 340 articles, identified from literature searches conducted for each of the nine instruments, were reviewed for relevance using the screening criteria noted above. Of these, 37 citations were selected for review of full-text articles. Most of the excluded abstracts were not studies of the specified screening instrument (e.g., the instrument shared its acronym with some other entity). After full-text articles were reviewed, 16 studies were ultimately included that addressed the validity, reliability or clinical utility of the screening instrument. Of these, 2 evaluated ASSIST, 3 evaluated CAGE-AID, 4 evaluated CRAFFT, 4 evaluated DAST, 2 evaluated RAFFT, and 1 evaluated SSI-SA. No studies reporting on assessments of DUDIT, RAGS or RDPS met the criteria for inclusion.

Expert Consensus

Not applicable

Systematic Review with Evidence Tables

Note from the National Guideline Clearinghouse (NGC): A staged review of the literature was prepared by the Oregon Evidence-Based Practice Center (EPC) for use by the U.S. Preventive Services Task Force (USPSTF). Following this, AHRQ staff conducted a separate review of recent literature on the accuracy, reliability, and clinical utility of instruments designed to screen for drug use among adolescents, adults and pregnant women (see the "Availability of Companion Documents" field).

Staged Systematic Review

Data Abstraction and Critical Appraisal

Data were extracted from each paper, entered into evidence tables, and, for key questions 4, 5, and 5a, the main findings were highlighted in a summary table, with trials categorized by population, drug, and treatment type. Information abstracted in an evidence table for trials of drug treatment included: target population, whether the population was screened/not screened in primary care, total number of patients, patient inclusion/exclusion criteria, type of drug(s) treated, treatment and control conditions, treatment duration and longest follow-up, results (by key question), whether results differed at short follow-up(s), and reviewer comment.  For key question 7, the following information was abstracted: study design, target population, whether the population was screened or not screened in primary care, total number of patients, inclusion criteria and sample description, exclusion criteria, type of drug(s), groups analyzed, length of follow-up(s), type of data analysis, outcome(s), results, and reviewer comment. A second investigator reviewed or abstracted studies if the initial investigator required confirmation of exclusion or inclusion criteria or data abstraction elements.

The quality of studies, including systematic reviews, was rated using design-specific criteria developed by the USPSTF and others (see Appendices C, D, and E in the Evidence Synthesis [see "Availability of Companion Documents" field]). Each study's overall rating is a combination of internal and external validity ratings. Throughout the literature review and data abstraction process, when reviewers disagreed, a final rating was reached through consensus.

Literature Synthesis

Since this staged review's primary purpose was to determine evidence sufficiency, EPC staff did not undertake quantitative data synthesis such as meta-analysis. These techniques are used to provide summary effect sizes or explore heterogeneity in systematic reviews of treatment. Instead, they qualitatively summarized the findings, with an emphasis on the best available evidence for each critical key question and the overall coherence of the evidence. This level of synthesis was appropriate to the decision being made by the USPSTF using this review.

Supplemental Review: Assessment of Screening Instruments

Data Abstraction

Full text articles of non-excluded studies were examined and critically appraised. When available, the following data were extracted from each study:

1. Type of patient population
2. Sample size
3. Reference standard used
4. Sensitivity
5. Specificity
6. Positive predictive value
7. Negative predictive value
8. Internal consistency (alpha score)
9. Test-retest coefficients (kappa values)

It was also noted if the instrument measured recent use or lifetime use, and if it had been evaluated for feasibility and/or clinical utility. ARHQ staff asked if assessment studies were conducted in primary care practice settings.

Critical Appraisal

Studies were rated using previously published USPSTF grading scales. Studies were considered of good quality if they used a credible reference standard, interpreted the reference standard independently of the questionnaire, and included more than 100 patients with and without a drug use problem, some of whom were from a general clinic population.

Studies were considered of fair quality if they used a reasonable, although not the best possible, reference standard, interpreted the reference standard independently of the questionnaire, and included a sample size of 50-100.

Studies were considered of poor quality if an inappropriate reference standard was used, there was a potentially biased ascertainment of the reference standard, or the study included a small (<50) sample size.

Balance Sheets
Expert Consensus

When the overall quality of the evidence is judged to be good or fair, the U.S. Preventive Services Task Force (USPSTF) proceeds to consider the magnitude of net benefit to be expected from implementation of the preventive service. Determining net benefit requires assessing both the magnitude of benefits and the magnitude of harms and weighing the two.

The USPSTF classifies benefits, harms, and net benefits on a 4-point scale: "substantial," "moderate," "small," and "zero/negative."

"Outcomes tables" (similar to "balance sheets") are the USPSTF's standard resource for estimating the magnitude of benefit. These tables, prepared by the topic teams for use at USPSTF meetings, compare the condition specific outcomes expected for a hypothetical primary care population with and without use of the preventive service. These comparisons may be extended to consider only people of specified age or risk groups or other aspects of implementation. Thus, outcomes tables allow the USPSTF to examine directly how the preventive service affects benefits for various groups.

When evidence on harms is available, the topic teams assess its quality in a manner like that for benefits and include adverse events in the outcomes tables. When few harms data are available, the USPSTF does not assume that harms are small or nonexistent. It recognizes a responsibility to consider which harms are likely and judge their potential frequency and the severity that might ensue from implementing the service. It uses whatever evidence exists to construct a general confidence interval on the 4-point scale (e.g., substantial, moderate, small, and zero/negative).

Value judgments are involved in using the information in an outcomes table to rate either benefits or harms on the USPSTF's 4-point scale. Value judgments are also needed to weigh benefits against harms to arrive at a rating of net benefit.

In making its determinations of net benefit, the USPSTF strives to consider what it believes are the general values of most people. It does this with greater confidence for certain outcomes (e.g., death) about which there is little disagreement about undesirability, but it recognizes that the degree of risk people are willing to accept to avert other outcomes (e.g., cataracts) can vary considerably. When the USPSTF perceives that preferences among individuals vary greatly, and that these variations are sufficient to make the trade-off of benefits and harms a "close-call," then it will often assign a C recommendation (see the "Recommendation Rating Scheme" field). This recommendation indicates the decision is likely to be sensitive to individual patient preferences.

The USPSTF uses its assessment of the evidence and magnitude of net benefit to make recommendations. The general principles the USPSTF follows in making recommendations are outlined in Table 5 of the companion document cited below. The USPSTF liaisons on the topic team compose the first drafts of the recommendations and rationale statements, which the full panel then reviews and edits. Recommendations are based on formal voting procedures that include explicit rules for determining the views of the majority.

From: Harris RP, Helfand M, Woolf SH, Lohr KN, Mulrow, CD, Teutsch SM, Atkins D. Current methods of the U.S. Preventive Services Task Force: a review of the process. Methods Work Group, Third U.S. Preventive Services Task Force. Am J Prev Med 2001 Apr;20(3S):21-35.

What the United States Preventive Services Task Force (USPSTF) Grades Mean and Suggestions for Practice

USPSTF Levels of Certainty Regarding Net Benefit

Definition: The U.S. Preventive Services Task Force defines certainty as "likelihood that the USPSTF assessment of the net benefit of a preventive service is correct." The net benefit is defined as benefit minus harm of the preventive service as implemented in a general, primary care population. The USPSTF assigns a certainty level based on the nature of the overall evidence available to assess the net benefit of a preventive service.

A formal cost analysis was not performed and published cost analyses were not reviewed.

Comparison with Guidelines from Other Groups
External Peer Review
Internal Peer Review

Peer Review. Before the U.S. Preventive Services Task Force makes its final determinations about recommendations on a given preventive service, the Evidence-Based Practice Center and the Agency for Healthcare Research and Quality send a draft evidence review to 4 to 6 external experts and to federal agencies and professional and disease-based health organizations with interests in the topic. They ask the experts to examine the review critically for accuracy and completeness and to respond to a series of specific questions about the document. After assembling these external review comments and documenting the proposed response to key comments, the topic team presents this information to the Task Force in memo form. In this way, the Task Force can consider these external comments and a final version of the systematic review before it votes on its recommendations about the service. Draft recommendation statements are then circulated for comment from reviewers representing professional societies, voluntary organizations and Federal agencies. These comments are discussed before the final recommendations are confirmed.

Comparison with Guidelines from Other Groups. Recommendations for screening from the following groups were discussed: American Academy of Pediatrics, the American Medical Association, the Bright Futures initiative, and the American College of Obstetrics and Gynecology.

The U.S. Preventive Services Task Force (USPSTF) grades its recommendations (A, B, C, D, or I) and identifies the Levels of Certainty regarding Net Benefit (High, Moderate, and Low). The definitions of these grades can be found at the end of the "Major Recommendations" field.

Summary of Recommendations and Evidence

The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening adolescents, adults, and pregnant women for illicit drug use. (This is an I statement)

Clinical Considerations

Patient Population Under Consideration: While the rate of illicit drug use in the U.S. is highest between the ages of 18-20 years, more than 10% of adolescents aged 12-17 are known to use illicit drugs. The percentage of adults who regularly use illicit drugs decreases steadily with age. About 5% of pregnant women report using illicit drugs within the past month.

Patterns of Drug Use: Marijuana is the most commonly used illicit drug in the U.S., with around 6% of the population age 12 and older admitting to use within the past month. While cocaine is the second most commonly used illicit drug, it is used by less than 1% of the population. Only a small minority of Americans use hallucinogens, inhalants, heroin, or illicitly manufactured methamphetamine, although the potential for abuse of, or dependence on, these substances is high. Illicit (non-medical) use of prescription-type drugs, categorized as pain relievers, tranquilizers, stimulants, and sedatives, is a growing health problem in the U.S.

Screening Tests: While clinicians should be alert to the signs and symptoms of illicit drug use in patients, the added benefit of screening asymptomatic patients in primary care practice remains unclear. Toxicologic tests of blood or urine can provide objective evidence of drug use, but such tests do not distinguish between occasional users and those who are impaired by drug use. A few brief, standardized questionnaires have been shown to be valid and reliable in screening adolescent and adult patients for drug use/misuse. However, the clinical utility of these questionnaires is uncertain. The reported positive predictive values are variable and at best 83% when the questionnaires are applied in a general medical clinic. Moreover, the feasibility of routinely incorporating the questionnaires into busy primary care practices has yet to be assessed. The validity, reliability and clinical utility of standardized questionnaires in screening for illicit drug use during pregnancy have not been adequately evaluated.

Treatment: Although drug-specific pharmacotherapy (e.g., buprenorphine for opiate abuse) and/or behavioral interventions (e.g., brief motivational counseling for cannabis misuse) have been proven effective in reducing short term illicit drug use, the longer term effects of treatment on morbidity and mortality have been inadequately evaluated. Moreover, these treatments have been studied almost exclusively in individuals who have already developed medical, social, or legal problems due to drug use, and their effectiveness in individuals identified through screening remains unclear. In all but one trial, treatment was delivered outside the primary care setting, often in specialized treatment facilities. More evidence is needed on the effectiveness of office-based treatments for illicit drug use/dependence.

Other Approaches to Prevention: While interventions to prevent or reduce illicit drug use have been proposed for use in schools and sites of employment, evidence assessing preventive measures delivered in settings other than primary care practice was outside the scope of the USPSTF review. However, the Centers for Disease Control and Prevention's (CDC's) Task Force on Community Preventive Services has announced plans to assess the effectiveness of selected population-based interventions for preventing or reducing abuse of drugs (other than tobacco and alcohol) and to make recommendations based on these findings.

Definitions:

What the United States Preventive Services Task Force (USPSTF) Grades Mean and Suggestions for Practice

USPSTF Levels of Certainty Regarding Net Benefit

Definition: The U.S. Preventive Services Task Force defines certainty as "likelihood that the USPSTF assessment of the net benefit of a preventive service is correct." The net benefit is defined as benefit minus harm of the preventive service as implemented in a general, primary care population. The USPSTF assigns a certainty level based on the nature of the overall evidence available to assess the net benefit of a preventive service.

None available

The type of supporting evidence is not specifically stated for each recommendation.

Benefits of Detection and Early Treatment

There is good evidence that various treatments are effective in reducing short term illicit drug use. Evidence is insufficient, however, either to demonstrate that treatment reliably improves social and legal outcomes for patients or to link treatment directly to longer term improvements in morbidity or mortality. Since all but one published clinical trial of treatment interventions involved individuals who had already developed problems due to their drug use, the generalizability of findings to asymptomatic individuals whose illicit drug use is detected through screening is unknown. There is fair evidence that, regardless of the patient's history of treatment, reducing or stopping drug use is associated with improvement in some health outcomes.

Harms of Detection and Early Treatment

There is little evidence of harms associated with either screening for illicit drug use or behavioral interventions used in treatment. Several clinical trials of pharmacotherapy for drug misuse have reported mild to serious adverse events, although some of these events were likely related to underlying drug use. The specific adverse events noted to occur more frequently in the treatment arm of trials (compared to placebo) have been previously recognized as potential side effects of the treatment medication and cited on its product label.

• The U.S. Preventive Services Task Force (USPSTF) makes recommendations about preventive care services for patients without recognized signs or symptoms of the target condition.
• Recommendations are based on a systematic review of the evidence of the benefits and harms and an assessment of the net benefit of the service.
• The USPSTF recognizes that clinical or policy decisions involve more considerations than this body of evidence alone. Clinicians and policy-makers should understand the evidence but individualize decision making to the specific patient or situation.

Staying Healthy

Effectiveness
Patient-centeredness

• U.S. Preventive Services Task Force (USPSTF). Screening for illicit drug use: U.S. Preventive Services Task Force recommendation statement. Rockville (MD): Agency for Healthcare Research and Quality (AHRQ); 2008 Jan. 7 p. [15 references]

Not applicable: The guideline was not adapted from another source.

1996 (revised 2008)

United States Preventive Services Task Force - Independent Expert Panel

The U.S. Preventive Services Task Force (USPSTF) is a federally-appointed panel of independent experts. Conclusions of the U.S. Preventive Services Task Force do not necessarily reflect policy of the U.S. Department of Health and Human Services (DHHS) or its agencies.

United States Government

U.S. Preventive Services Task Force (USPSTF)

The U.S. Preventive Services Task Force has an explicit policy concerning conflict of interest. All members disclose at each meeting if they have a significant financial, professional/business, or intellectual conflict for each topic being discussed. Task Force members with conflicts may be recused from discussing or voting on recommendations about the topic in question.

This is the current release of the guideline.

This version updates a previously published guideline: U.S. Preventive Services Task Force. Guide to clinical preventive services. 2nd ed. Baltimore (MD): Williams & Wilkins; 1996. Chapter 53, Screening for drug abuse. p. 583-95. [80 references]

This summary was completed by ECRI on June 30, 1998. The information was verified by the guideline developer on December 1, 1998. This NGC summary was updated by ECRI Institute on January 15, 2008. The updated information was verified by the guideline developer on January 17, 2008.