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