Clinical Preventive services (United States Preventive Services Task Force CHAPTER OUTLINE A. Mission and History 1. UNITED STATES PREVENTIVE SERVICES TASK FORCE 217 When the USPSTF was first convened by the U.S.Public Health service in 1984. it was modeled on an earlier B. Underlying Assumptions 217 Canadian task force to serve as an independent panel of C. Evidence Review and Recommendations 2 8 experts on prevention and evidence-based medicine(EBM) II. ECONOMICS OF PREVENTION 220 Since 1995, the Task Force has worked under the Agency of A. Overuse, Underuse, and Misuse of Screening 220 Healthcare Research and Quality (AHRQ). It covers all Ill. MAJOR RECOMMENDATIONS 221 rimary and secondary preventive services, including screen A. Highly Recommended Services 221 ing, counseling, and specific chemoprophylaxis. The Task B. Limits of Evidence 224 Force aims to provide accurate and balanced recommenda tions across a spectrum of populations, types of services, and IV, COMMUNITY-BASED PREVENTION 225 disease types. Its mission is t V. SUMMARY 225 1. Assess the benefits and harm of delivering preventive ser REVIEW QUESTIONS, ANSWERS, AND EXPLANATIONS O (based on age, ger ch services should be primary care. This mission is very circumscribed, The USPSTF only considers screening of asymptomatic patients, and it only deals with services within primary however. USPSTF sized by cialist organizations. Specialists may primarily see prese In Chapter 16, we explored how screening is, in the most lected patients with subtler symptoms that were missed literal sense, "looking for trouble. " Looking for trouble makes earlier or may see high-risk groups. Screening decisions for ense if, by finding it early, it can be fixed. But if you dont such patients may be different from those for the general know what to do with the trouble you find, you are no longer population, because the pretest probability of disease is just looking for trouble, you are asking for it. The credibility much higher. On the other hand, recommendations of of preventive medicine depends on the following two goals: USPSTF are sometimes used for insurance decisions about a Screening is only done if it meets rigorous standard which screening tests to cover. In these cases, recommenda The screening test can real istically be integrated in the tions may be more broadly applied than intended. In con- busy practice of all clinicians trast to the Community Preventive Services Guide(see Chapter 26), the USPStF does not take cost-effectiveness or financial concerns into consideration When the USPSTF was founded, its principles were revolu- . UNITED STATES PREVENTIVE tionary: that preventive care should be rigorously evaluated, and that not every screening test was worth doing. In its history, SERVICES TASK FORCE USPSTF has often recommended against or failed to endorse screening tests that were recommended by other organizations. The U.S. Preventive Services Task Force(USPSTF)was The reason for this reluctance to endorse some interventions founded in 1984 to address these goals. This chapter focuses may be based on several assumptions of the Task Force on why its work is important and how busy clinicians can keep up-to-date with and incorporate the Task Force's rec ommendations. Recommendations for clinical preventive B. Underlying Assumptions ervices change frequently with emerging evidence. For more As outlined in Chapter 16, screening studies are subject to details and updated recommendations, readers should many biases that lead researchers to overestimate benefits. consult USPSTF online(see Website list at end of chapter). Therefore the Task Force places a higher burden of evidence
SECTION 3 Preventive medicine and public health for benefits than for evidence of harm For benefits, USPSTF helical computed tomography(CT). The number of patient ill only accept evidence from randomized controlled trial ives potentially saved must be weighed against the risk of (RCTs), community trials, meta-analyses, or systematic subjecting healthy patients to potentially harmful screening reviews However, it will take into account evidence of cohort tests. with this tension and when in doubt the Task force studies and case-control studies in calculations of harm seems to prefer being late to being wrong Prevention studies describe the upper bounds of efficacy In other words, controlled trials describe a best-case scenario with well-trained and highly motivated providers and C. Evidence Review and Recommendations tients. The Task force assumes that in the real world, with Developing a recommendation is a two-part process: review- unselected providers and in the general population, the ing the evidence and formulating recommendations effectiveness of a screening program will be lower Although the Task Force itself makes the recommendations, Delivery of a screening service is not an outcome. Diag independent centers review the evidence. USPSTF has estab nosis of a disease also is not an outcome. Therefore the lished 12 such evidence-based practice centers(EPCs). The benefit of a screening program lies not in the number of literature review and recommendation process is highly atients screened or the number of patients diagnosed with structured and includes various steps to safeguard the Task disease, but only in the health outcomes. Health outcomes Force's integrity and to help it pursue its goals of transpar are changes in a patient's health or health perception, such ency, accountability, consistency, and independence(Table outcomes, intermediate outcomes are measurements of members, stringent policies regarding conflict of interest, pathology or physiology that can lead to health outcomes dual review of each abstract, and a comment period for com (e.g, high blood pressure). USPSTF will give no weight to munity partners and the public evidence of number of screening events or cases found, and it gives greater weight to studies of health outcomes than to CRITICAL APPRAISAL QUESTIONS those of intermediate outcom Do the studies have the appropriate research design to Because the standard for evidence is so high, USPSTF may answer the key question wait longer than other organizations before endorsing What is the internal validity? screening modalities, as with lung cancer screening using What is the external validity? Table 18-1 Procedures for Developing a Recommendation Statement Activity Responsible Parties Timeline Topic selection Topic Prioritization Workgroup, a subset of Task The Workgroup meets periodically Force members and AhRQ and EPC stafl Work plan developme The EPC writes work plans with guidance from a From start to finish, these activities development, peer review, and approval-take 3-6 months plan peer review work plans are reviewed by experts in the field reviewed work plant All members of USPSTE Evidence reports are written by EPC or by AHRQ Peer review of by lest for review, and Task force leaders are Draft recommendation statement Task force members draft recommendatio Completed within 2-4 weeks, with AHRQ med USPSTF review of cvidence and vote All members of USPSTF on draft recommendation statement Final evidence report EPC and AhrQ medical officer incorporate itted to aHRQ within 3-6 mont eviewer comments and finalize evidence report. fter USPSTF vote Peer review of draft recommendation 22 partners of USPSTF Partners typically have 2-3 weeks to Approval of final recommendation Task Force members USPSTF members typically approve atement recommendation statement as final Release of recommendation statement HRO staff Time from vote to release ( journal and posting on website)of recommendation varies odified from Guirguis-Blake 1: Ann Intern Med 147: 117-121, 2007. rs at a Task Force meeting, alt in the case of topic updates, work plan peer review and Task Force approval are exceptional rather than usuaL. edicare and Medicaid Services, Food and Drug Administration, Indian Health Service, National Institutes of Health, AHRQ, Agency for Healthcare Research and Quality; EPC, evidence-based practice center; USPSTF U.S. Preventive Services Task Force
CHAP ER 8 CLinical Preventive Services (united States Preventive Services Task Force) How many studies have been conducted that address the ey question, and how large are the stuc GRADING SERVICES How consistent are the results Once Task Force members have answered these questions, I Are there additional factors that raise confidence in the the group assigns a grade for the service of A, B, C, D, or I results(e. g, dose-response effects, consistency with bio- (Table 18-2). After assigning a tentative grade, the Task Force logic models)? discusses these recommendations with federal and primary are partners. Federal partners include the Centers for TASK FORCE MEMBERS Disease Control and Prevention( CDC), Center for Medicare and Medicaid Services(CMS), Health Resource and Services Sixteen members serve on the Task Force at any given time. Administration (HRSA), National Institutes of Health About 25% of USPSTF members are replaced each year (NIH), and Food and Drug Administration(FDA) Exam Members are nominated in a public process and are chosen ples of primary care partners include the American Medical their expertise in the subject matter, research Association, American College of Physicians, and American disease prevention, application of synthesized evi College of Preventive Medicine dence to clinical decision making, and clinical expertise in The results of the evidence review and the task force primary health care. They are chosen through a rigorous recommendations are posted for comments by the partners process and serve staggered 4-year terms on the committee. and public, published in reputable journals, and dissemi- KEY QUESTIONS In clinical practice there is little difference between gra A and b recommendations: in both cases the service should Once an evidence review is complete, USPSTF members vote be strongly encouraged. Services with grades of C, D, and I the eight key questions that determine if screening for a should not be routinely used. However, it is important to understand the difference between these grades For grades A through D, USPSTF is reasonably certain it understand I. Does screening for X reduce morbidity and/or mortality? the balance of benefits and harm. For services graded C, 2. Can a group at high risk for X be identified on clinical there is a net benefit, but it is likely small. A service with a C grounds? recommendation is breast cancer screening for women 3. Are accurate screening tests available? younger than 50(see Chapter 16). Decisions about these C 4. Are treatments available that make a difference in inter- services should be individualized. In contrast for services mediate outcomes when the disease is caught early? graded D, there is clear evidence that there is no net benefit, 5. Are treatments available that make a difference in mor- or that there is net harm; an example is screening for ovarian bidity and mortality (patient outcomes) when the disease cancer. These D services should be avoided. is caught earl 2. For services with an I grade, evidence is lacking or con- 6. How strong is the association between the intermediate flicting, and the Task Force has determined that they can outcomes and patient outcomes neither recommend for nor recommend against the service. 7. What are the harms of the screening test As of 2012, services with an I grade include skin cancer 8. What are the harms of treatment? screening, colorectal cancer screening with CT colonography Table 18-2 Grades Assigned to Screening Recommendation and Suggestions for Practice Grade Defnition Net Benefit Suggestions for Practice USPSTF recommends the service High certainty for net Offer/provide this service. USPSTF recommends the service Offer/provide this servi ertainty for net uSpstf does certainty that the other considerations support the net benefit is smal offering or providing the service or symptoms, an In there is likely to be only a small benefit from this service. D USPSTF recommends against the se derate or high Discourage the use of this service. certainty of SPSTF concludes that current evidence is insufficient to No certainty Read Clinical Considerations section the balance of benefits and harms of the servic balance of benefits/ of USPSTF Recommendation Evidence is lacking, of poor quality, or conflicting Statement. If the service is the balance of benefits and harms odifiedfromhttp://www.uspreventiveservicestaskforce.org/uspstto7/ratingsv2.htm. USPSTE U.S. Preventive Services Task Force
20 SECTION 3 Preventive medicine and public health and screening for lung cancer using helical CT. These ser vices require the most time to discuss, and patients and clini Use of aspirin in persons at high risk for cardiovascular cians should engage in shared decision making to understand consequences of testing and of not testing, as well as the patient s risk preferences. Such shared decision making is not According to the National Commission on Prevention only time-consuming but also requires some sophisticated Priorities, 100,000 deaths could be averted each year by evaluation of trade-offs on both sides increasing delivery of five high-value clinical preventive ser vices. Increasing use of these services might be cost-neutral or even cost-savin Table 18-3 provides one ranking of preventive services by I. ECONOMICS OF PREVENTION considerations of cost-effectiveness, Clinically preventabl burden(CPB)is the disease, injury, and premature death Attitudes towards preventive services vary. Some people that would be prevented if the service were delivered to all believe that prevention must be a good in itself. Intuition people in the target population. Cost effectiveness(Ce)is a suggests that finding problems early will make them easier standard measure for comparing services' return on invest- the other end of the spectrum are health economists, who impact, least cost-effective, among these evidence-based pre- gue that prevention rarely reduces costs and that preven tive services should be used very selectively.' A more balanced approach focuses on value. Health public good. We do not expect other public goods (e.g, A. Overuse, Underuse, and Misuse of Screening money spent on public goods should be spent wisely, we In clinical practice, it is difficult(1)to deliver all highly effec- should try to obtain as much health as we can with every tive preventive services consistently,(2)to avoid the less dollar spent. In a setting of limited health care resource effective ones, and (3)to deliver services only to patients who monies for disease care and prevention should go toward will derive benefit. This may be even more difficult with the those services that deliver the most health. Fortunately, the ascendancy of "patient-centered care; patients may have following core set of preventive services has proved highly priorities driven by passions, convictions, anxieties, and marketing that conflict with evidence-based guidelines Strong evidence exists for underuse of highly effective a Screening for hypertension, dyslipidemia, obesity, colorectal services. In the landmark Community Quality Index study and cervical cancer, and breast cancer in women over 50 published in 2003, only 54.9% of patients received all recom Childhood and adult immunizations mended preventive services. This is partially driven by Table 18-3 Ranking of Preventive Services for u.S.Population Clinical Preventive services CE Total daily aspirin use--men 40+, women 50+ Alcohol screening and brief counseling-adults Hypertension screening and -adults 18+ nfluenza immunization ad Vision screening--adults 65+ 3 Cholesterol screening and treatment--men 35+, women 45+ Pneumococcal immunizations-adults 65+ Chlamydia screening-sexually active women under 25 Discuss calcium supplementation-women Vision screening--preschool childre Discuss folic acid use--wwomen of childbearing age Obesity screening-adults Depression screening-adults of children 232 holesterol screening-men< 35, women 45 at high risk Diet counseling-adults at risk Tetanus-diphtheria booster-adults difiedfromhttp://ww prevent.org/National-Commission-on-Prevention-Prioritie es/Rankings -of-Preventive-Services-for-the-US-Population, aspx. CPB, Clinically preventable burden; CE, cost-effectiveness
CHAP ER 8 CLinical Preventive Services (united States Preventive Services Task Force) imbursement; Medicare pays for 93% of recommended clinicians is therefore twofold:(1)find more efficient way reventive services for adults, but the required counseling to deliver preventive services to patients who need them and and coordination are mostly unreimbursed. In a typical (2)discuss goals of care and expected benefits of screening linical practice, urgent problems and symptomatic condi- with patients who are unlikely to benefit. This will probably easily supersede conversations about health require rethinking the delivery of care. No one provider can maintenance. provide the array of preventive services and counseling nec- The Task Force recommends that clinicians track delivery essary in a series of brief, one-on-one encounters. The solu of all services with an A or a B grade for every patient to tion may lie in a team-based model, such as the chronic care ensure that all patients receive these services. Many elec model(see Chapter 28 tronic health records feature reminders at the point of care It is even more difficult to have a meaningful conversation to help providers integrate preventive services. Alternatively, about services that depend on patient preferences for risk, and for paper charts, an assistant can check if the patient is such as those graded c (and some graded B, such as chemo due for recommended services and can prepare screening prevention of breast cancer), or services with conflicting test requisitions in advance. In either case, the time required evidence(graded I). Many patients strongly demand services is considerable. Some authors estimate it would take 7. 4 based on anecdotal evidence from friends, family member hours per workday just to incorporate all recommended ser- or the media. For these services, the Task Force to primary care. This problem might prove intrac community education, use of shared decision ntil the implementation of more innovative care and trained assistants. However, such a sophis odels that link payments to long-term outcomes and personnel-intensive approach is probably not feasible for thereby make prevention an efficient use of practice time many primary care providers (see Chapter 29, Cost Containment Strategies owever, the problem is not only lack of time and reim bursement.Strong evidence also exists for overuse and lll. MAJOR RECOMMENDATIONS misuse of screening services. Medicare reimburses physi cians for 44% of services that have a d rating from the ta A. Highly Recommended Services Force. A large proportion of Medicare patients undergo screening colonoscopies more frequently than recom Table 18-4 lists preventive services that rating of A or mended. Screening is overused in elderly patients and B from USPSTE Recommended services are skewed toward patients in poor health and at the end of life, who screening: About 25 screening services are recommended, unlikely to benefit from screening. The challenge for versus seven counseling services and seven chemoprevention Table 18-4 Recommended Preventive Health Care Screening Services Recommendation Date in Effect Abdominal aortic aneurysm One-time screening for abdominal aortic aneurysm by February 2005 ning: men ultrasonography in men age 65-75 who have ever smoked. Screening and behavioral counseling interventions to reduce alcohol April 2004 misuse by adults, including pregnant women, in primary care Aspirin to prevent cardiovascular 9 when potential benefit of reduction March 2009 disease: mer gastrointestinal hemorrhage. Aspirin to prevent cardiovascular se of aspirin in women age 55-79 when potential benefit of A March 2009 disease. women reduction in ischemic strokes outweighs potential harm of Bacteriuria screening: pregnant Screening for asymptomatic bacteriuria with urine culture for pregnant women at 12-16 weeks gestation or at first prenatal visit, if later Blood pressure screening: adults Screening for high blood pressure in adults age 18 or older. December 2 CA screening bout for deleterious mutations in BRCAI or BRCA2 genes for genetic counseling and evaluation for BRCA testing uly 2002 and at low risk for adverse effects of chemoprevention. Clinicians lould inform patients of potential bene Breast cancer screening Screening mammography for women, with or without clinical breast December 2009 Individualize decision to start mammography earlier than age 50. mber 2009 Breastfeeding counseling e interventions during pregnancy and after birth te