Chapter 8 Improving Health

Improving Health

After reading this chapter you will be able to:

  • Consider the broader goals of health care in terms of disability-free survival;
  • Summarize the arguments for preventive interventions at the individual patient level versus on the whole population;
  • Describe the advantages and disadvantages of identifying and treating individuals versus implementing population-level approaches to prevention (MCC objective 78-3)
  • Describe strategies for community needs assessments, health education, community engagement and health promotion (MCC 78-3)
  • Apply survival curves in describing the outcome of an intervention (78-2)
  • Describe the main functions of public health related to population health assessment, (…) disease and injury prevention, health promotion and health protection (78-4)
  • Appreciate the role that physicians can play in promoting health and preventing diseases at the individual and community level (e.g. prevention of low birth weight, immunization, obesity prevention, smoking cessation, cancer screening, etc.) (78-3)
  • Illustrate ways the clinician can incorporate prevention in routine practice (78-12)
  • Understand how public policy can influence population-wide patterns of behavior and affect the health of a population
  • Name and describe the common methods of health protection (such as agent-host-environment approach for communicable diseases, and source-path-receiver approach for occupational/environmental health).
  • Describe one or more models of patient behavior change, including predisposing, enabling and re-enforcing factors and the stages of change (78-3)
  • Identify the potential community, social, physical, environmental factors and work practices that might promote healthy behaviors, as well as ways to assist communities and others to address these factors (78-3)
  • Be able to describe the health impact of community-level interventions to promote health and prevent disease (78-3)

Linking these topics to the Medical Council exam objectives, especially section 78-3.

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Words in CAPITALS are defined in the Glossary

No disease, no problem?

Dr. Rao is seeing David Richards. Four weeks ago David went to the city emergency room with a cough. He was given antibiotics. The ER doctor suspected underlying asthma, so she referred David back to Dr. Rao for follow-up. With a detailed history, knowing the family, and having examined the respiratory system, Dr. Rao is fairly certain that David doesn’t have asthma. However, he notes that David smokes tobacco and marijuana and regularly drinks more than 5 units of alcohol in one sitting. He also pays little attention to safety. He doesn’t always use his car seat belt. Although he works in construction, he doesn’t have steel-capped boots and doesn’t bother with ear protectors on noisy jobs, although he usually wears his hard hat on work sites. David has a steady girlfriend and occasional “one night stands.” He uses condoms only if his partner insists. Dr. Rao decides he has to do something to help David to reduce his health risks.

The Goals of Health Care

In principle, health care aims to reduce morbidity and mortality. A person’s health and quality of life declines over time through exposure to noxious factors, at a varying rate until death. For a population, this can be represented by SURVIVAL CURVES, as in Figure 8.1. The red curve shows the proportion of people who remain alive at each age (see Chapter 6). The blue line shows the declining health of a population: the area below it indicates the proportion of the population in each age group who are in good health. Health care that prevents—or at least delays—the onset of potentially fatal diseases shifts the red curve up and to the right, so its shape becomes more rectangular. But shifting only the survival curve would increase the area between it and the blue, disability-free survival curve, a gain in life-years at the expense of an increase in disability. Reassuringly, however, preventive actions that extend life also seem to improve health, and a combination of disease prevention and health promotion tends to raise the disability-free survival curve, compressing morbidity. This “squaring of the curves” describes the hoped for delay in age-related declines in health so that people enjoy a good quality of life for as long as possible and die as late as possible.

Figure 8.1: Squaring mortality, compressing morbidity (Adapted from Fries1)
Figure 8.1: Squaring mortality, compressing morbidity (Adapted from Fries1)

Prevention or treatment?

Chapter 4 introduced the stages of prevention but made the point that these are arbitrary distinctions that only have heuristic value. Chapter 1 showed that the definition of “disease” is also arbitrary. Many experts likewise believe that the distinction between disease and risk factors is artificial: it depends on the point in the disease’s natural history that is being considered. Tobacco addiction, hypertension, and diabetes are generally considered diseases in themselves that need to be treated. However, treating them can also be thought of as a way of reducing the risk of chronic lung disease, stroke and renal disease, respectively. Even surgery following subarachnoid haemorrhage has no effect on the haemorrhage that has occurred or on its effects: it simply aims to prevent another one.

According to the WHO, “disease prevention covers measures that aim not only to prevent the occurrence of disease, such as risk factor reduction, but also to arrest its progress and reduce its consequences once established.” This implies that all effective clinical interventions prevent something: the occurrence, progression or duration of disease, or its resulting disability or handicap.2

One way to think about the distinction between prevention and treatment is that preventive interventions are applied to patients who do not have symptoms of the targeted disease and who have often not solicited the intervention. Intervening in an ostensibly healthy patient, especially one who has not asked for it, adds to the importance of the clinician taking care to minimize harm, maximize benefit, and ensure informed consent. For both treatment and prevention, the risks and benefits of intervening versus not intervening should be assessed and discussed with the patient in every case. Offitt provided a detailed history of the hazards of medical innovations.3

Intervening in Individuals or in Populations?

There are two main approaches to squaring the survival curve: the first is to identify individuals at high risk and intervene to reduce their risk. The second is to reduce the average risk level for the whole population; sometimes this occurs without the consent or even knowledge of people in the population.

The justification for a population approach comes from the work of Geoffrey Rose4 who noted that many cases of disease arise in people who are not in a high-risk group. Moreover, more cases often arise among people at average risk than among those at high risk simply because there are so many more people at average risk in a population. To illustrate, Figure 8.2 uses Canadian data to show that 61% of cases of diabetes mellitus arose from people in low or moderate risk BMI categories, versus only 39% from in high-risk BMI categories. Rose showed similar patterns for heart disease, hypertension, and trisomy 21, and there are many other examples.

Figure 8.2 Comparison of the number of incident cases of diabetes by category of body mass index, Canada 2007-2017.4
Figure 8.2 Comparison of the number of incident cases of diabetes by category of body mass index, Canada 2007-2017.5

Rose proposed that preventing disease by trying to achieve a small shift in the distribution of a risk factor in an entire population can be more efficient than trying to identify everyone at high risk and getting them to drastically reduce their risk. For instance, estimates suggest that in North America an equal reduction in the number of cerebrovascular accidents could be achieved either by decreasing the average blood pressure by just 2 mm Hg or by successfully identifying and treating everyone with a diastolic pressure of 95 mm Hg or greater.6 However, not all diseases are amenable to this type of population strategy. For instance, an analysis of the potential effects of cholesterol reduction to prevent coronary artery disease suggested that a high risk strategy is more likely to be effective than a population strategy.7

Trisomy 21: high risk and population strategies:

Comparing the total elimination of risk in a high-risk group versus a small reduction of risk in the entire population

The following table shows historical figures that Rose used to illustrate his arguments;4 they refer to the risk of giving birth to a child with trisomy 21 by maternal age group in 1979.8 Women aged 35 and over are considered to be at high risk for bearing a baby with trisomy 21. If screening were aimed at this group and was 100% effective in identifying trisomy 21 births in advance, this would only identify a small fraction of cases (6: 5+0.95+0.05 – see column “Number of trisomy 21 births”).

Distribution of trisomy 21 infants by the mother’s age (data from England and Wales).

Mother’s age Total births Trisomy 21 per 1,000 births Number of trisomy 21 births
Under 30 111,429        0.7    78
30 to 34  12,308       1.3    16
35 to 39    1,351      3.7     5
40 to 44       73    13.1          0.95
45 and over        1    34.6         0.05
Total 100 

By contrast, if a population-wide screening program were just 80% sensitive it would identify far more: 80 cases in advance, although at immense cost. Rose illustrated the hypothetical impact of a population-wide intervention that reduced the risk by just 0.1 per thousand in all age groups:

Impact of reducing risk of trisomy 21 births by 0.1 per thousand across all maternal ages

Mother’s age Total births Trisomy 21 per 1,000 births Number of trisomy 21 births
Under 30 111,429   0.6 67
30 to 34  12,308   1.2 15
35 to 39    1,351   3.6  5
40 to 44        73 13.0       0.94
45 and over         1 34.5       0.05
Total 87

Lowering the risk of trisomy 21 by just 0.1 per thousand pregnancies in all age groups would reduce the total number of trisomy 21 births by 13 – twice as good as the high-risk strategy.

Table 8.1 summarizes arguments for and against individual, high-risk approach and the alternative, average-risk population strategy.

Table 8.1: High-risk versus population strategies (adapted from Rose4)

Individual-centred “high-risk” strategy Population “average-risk” strategy
Advantages Intervention is relevant to the individual.
People who learn that they are at high risk should be more motivated to change their behavior to reduce their risk (as predicted by the Health Belief Model – see Chapter 2).
Physicians feel justified in reducing risk factors in high-risk patients.
Arguably cost-effective as resources are directed to individuals most in need.
Favourable benefit to risk ratio: high-risk individuals are likely to gain more benefit from the intervention for the same likelihood of harm as lower-risk individuals.
Intervention aimed at roots of problem reduces illness in the whole population so is egalitarian; it lessens the possibility of creating prejudice against high-risk groups.
Tackles condition before the risk factor causes irreversible damage.
A small change in the level of a risk factor in a population can improve the health of a large number of people.
Can engage self-sustaining social change—as non-smoking becomes the norm, smokers smoke less and are more likely to attempt to stop smoking.
Disadvantages Difficulties and costs of identifying high risk groups and individuals.
Dividing line between average and high-risk is often arbitrary, and many “average-risk” people can still be at risk.
Reaches those most at risk but has little impact on the disease burden in society, because most cases of disease occur in people at low or moderate risk.
Palliative and temporary—the determinants are not addressed, so there will always be individuals who need the intervention.
May be socially inappropriate—a change of behavior sufficient to reduce risk significantly may put the individual outside the norms of his or her social circle.
Those not at risk will derive minimal benefit and this may be outweighed by the risk of the intervention, even if this is also small.
Inefficient: it imposes change on a large number of people who would not have developed the disease at all.
There is little intrinsic motivation for low-risk individuals to change behavior; indeed, there may be opposition to change.
There is a danger of increasing inequity in health9 (see Chapter 2) as vulnerable people most in need of change are often the least likely to do so, while less vulnerable but more health-aware people may make the change.
Intervening in apparently healthy people may be interpreted as coercion, which is ethically more complex than intervening in people with health problems who are seeking care.

Although Rose’s arguments may eventually become obsolete (See Nerd’s corner – The case against Rose), for the moment, intervention strategies should combine individual and population approaches. For instance, preventing the complications of hypertension should include the promotion of healthy nutrition and physical activity in the general population as well as screening and treating people at risk.

The case against Rose

Geoffrey Rose published his article “Sick individuals and sick populations” in 1985, followed by his book The Strategy of Preventive Medicine in 1992.10 His ideas initially stimulated major interest, but were also  criticized. The ethics of a population approach were criticized, as for many diseases evidence of causation comes from observational studies and risk factors are not necessarily causal. Preventive actions should be based on solid evidence, but controlled trials on entire populations would be difficult. Intervening on the lives of all people without a scientifically secure basis raises the possibility of abuse.11

It was also argued that Rose’s view of the high-risk intervention approach was unduly negative. With improved understanding of risk factors, it should be possible to target interventions more precisely to those at risk, increasing the effectiveness of a high-risk approach for specific diseases. Rose’s demonstration focused on the use of a single marker to identify those at risk, whereas more recent risk algorithms, some of which include genetic markers, allow more accurate identification of high-risk individuals. Nowadays the risk of diabetes would not be predicted from BMI alone, but by a risk calculator that includes other variables. Applying these algorithms may prove more effective in lowering the burden of specific diseases than the use of population strategies.7

Population Interventions

Public health interventions have traditionally been of two main types. Universal approaches apply Rose’s theory and address whole groups, such as all adults, or all women over age 40. Narrower, targeted interventions apply to a priority, defined sub-group within the population that is disproportionately affected by a condition, such as those living in poverty, or racialized groups. More recently, these two approaches have been blended and “targeted universalism” describes programs designed for priority sub-groups but that are also open to anyone in the population. Alternatively, “proportional universalism” programs deliver a different volume, intensity, or type of intervention based on need.12 For example, breast cancer screening or childhood immunisation are organised on a population basis but can also be actively promoted among those in most need.

Health promotion

Chapter 4 described the Ottawa Charter for health promotion and to apply it the Public Health Agency of Canada developed an “integrated model of health promotion” – see Figure 8.3. In planning a health intervention, the integrated model asks: Who needs the intervention? What should the intervention target? How should the objectives be achieved? The answers should be based on evidence, considering health determinants and patients’ and populations’ priorities, the services available and any ethical issues relating to potential interventions.

Figure 8.3: Integrated model of population health promotion11
Figure 8.3: Integrated model of population health promotion13

Community mobilization is the strategy of choice for sustainable health promotion. Unlike earlier, top-down health education campaigns, community members are involved in defining the problems and in proposing solutions. Over time, this empowers local groups and promotes a healthy community. Health promoters believe that population health should be the responsibility of all members of a population or community, and a core responsibility for all government departments.14, 15 The variety of health determinants (see Chapter 2) implies a need to involve a wide range of academic disciplines, professions, and organizations.

Examples of government-led universal interventions that target health determinants include income redistribution policies aimed at alleviating poverty. Poverty reduction and improving built environments can address many health determinants and risk factors at once. For instance, walkable neighbourhoods with traffic calming measures encourage people to become physically active; well-lit neighbourhoods reduce the risk of accidents and crime, and increases the sense of security. However, such broad interventions can be difficult to bring about because they require collaboration across a number of sectors, each with its own agenda.

Targeted interventions by government and public health agencies to reduce particular diseases include legislation, awareness raising, community development and implementation of health programmes. Examples include legislation which allows the addition of iodine to salt to reduce goitre, the replacement of vitamin D removed by skimming milk or replacement of B vitamins removed with the bran in the processing of wheat flour. Raising public health awareness of the illnesses caused by tobacco and alcohol paved the way for legislation on advertising and sales.

Harm reduction

Sometimes community or individual priorities do not support the healthiest choices. For example, community members may vote against building a halfway house for ex-prisoners in their neighborhood; a person who uses drugs may want to continue doing so or is not ready to stop using all drugs. In such cases, a harm reduction approach may be useful. Harm reduction accepts that risk is an unavoidable part of our world. It can be difficult – even impossible – to eliminate the risk, but its harmful effects can be reduced. The approach is generally talked about in relation to substance use. Interventions include safe consumption sites, drug checking, providing clean equipment to prevent sepsis, or ensuring access to (and use of) naloxone.

Harm reduction

Harm reduction refers to reducing the negative consequences of risky behavior, rather than trying to eliminate the behavior itself, for instance smoking outdoors so children are not exposed to second-hand smoke in the house. It can be defined as a set of practical strategies that help reduce the risks associated with a danger (adapted from the U.S. Harm Reduction Coalition, 2000; definition supported by Canadian AIDS Society, 2000).

Harm reduction has evoked significant debate and is often opposed by people who disapprove of the risky behavior. For example, placing condom vending machines in high school washrooms raises the argument that it condones, even encourages, sexual activity. Similarly, providing safe consumption sites and clean equipment is construed as condoning illegal drug use. In particular, providing clean equipment is prisons may be seen as unacceptable because drugs are banned from prison anyway.

Nonetheless, from a health perspective, however, if efforts to eradicate a behavior fail repeatedly, it is logical to implement evidence-based approaches that reduce the harm associated with it. There is also an ethical argument to provide services or interventions regardless of the individual’s decision to continue practicing the behavior. This does not mean that attempts to reduce the risky behavior should be abandoned. Harm reduction is just one component in reducing the burden of unhealthy behavior. Others are healthy public policies, prevention, treatment, and enforcement.16

Safer injection information for people who use recreational drugs

Here is an excerpt from Sharp Shooters, an information pamphlet from CATIE, Canada’s source for HIV and hepatitis C information:17

Everything new:

  • Use new needles, syringes, filters, water and cookers every time you inject drugs.
  • Use your own gear, don’t share with others, and follow steps for safer injecting to lower your chance of damaging your veins and getting bacterial infections or viruses that are passed through the blood, like hepatitis B, hepatitis C and HIV.

Reduce the chance of a fatal overdose:

  • The best way to prevent a fatal overdose is to not use alone.
  • Stagger use with other people so someone is able to respond if an overdose happens.
  • Carry naloxone, know how to use it and let others know you have it.
  • Start low, go slow
  • Know the source of your drugs and inject yourself.

Take a break and take care of yourself:

  • Be kind to yourself, your skin and veins.
  • Take breaks and get some sleep.
  • Eat something before you use. Stay hydrated with water or juice.
  • Have condoms and lube with you.
  • Take care of your veins and use different sites.

Politics and harm reduction

In 2003, North America’s first supervised injection facility, Insite, was established in Vancouver’s Downtown Eastside, one of Canada’s poorest neighbourhoods. There were an estimated 12,000 injection drug users in Vancouver, one third of whom lived in the Downtown Eastside. Insite was designed to increase access to health care and addiction services, to reduce overdose-related death and reduce the transmission of blood-borne infections.18

Insite users bring their own drugs to an injection booth where they are provided with clean injection equipment, including needles. Nurses, trained to respond to overdoses, supervise the injections. Insite also provides onsite addictions counselling and referral to detoxification facilities and other forms of community support, as well as providing a point of access to the health care system for drug users who are not otherwise well connected.18

The facility has been successful in connecting its patrons to substance use treatment services. It has reduced the number of deaths from overdoses, decreased transmission of HIV and HCV, and it is associated with a decrease in high-risk behavior, including needle sharing.19  Insite has also led to improved public order, with decreased rates of public injecting and less injection-related litter and is cost-effective.20, 21 Its critics argue that safer injection facilities will lead to an increase in drug-related crime and promote drug use in the community, but these claims are not supported by the current evidence.22

Insite initially operated under a Health Canada exemption from prosecution under federal drug laws. Despite the growing body of evidence supporting safer injecting facilities, in 2006, when the pilot phase was due for renewal, the federal government threatened to withdraw this exemption and close the facility. But local community-based organizations, with the support of the scientific and medical community, took the federal government to court, stating that federal drug policy was inconsistent with the Charter of Rights and Freedoms. On May 27th 2008, a provincial judge found in their favour and Insite remained open. Since this time, the BC Court of appeal has upheld this ruling. In September 2011, the Supreme Court of Canada was unanimous in its decision to allow Insite to continue operating. An early history of Insite was given by Dooling et al.,23 while a systematic review of injection sites suggests they reduce morbidity and mortality, and neither increase crime nor cause public nuisance.22 

The success of Insite led to the establishment of dozens of supervised consumption sites across Canada. On a daily basis, it is estimated that 2,700 visits take place. Between 2017 and June 2023, more than 360,000 unique clients sought services. During that same time period, there were approximately 49,000 overdoses and other medical emergencies, with no reported deaths on-site.24

To read about Vancouver’s safe injection Insite, visit the Vancouver Coastal Health website.

Using a market model to reduce substance abuse

Three strategies derived from market economics may also help to reduce substance use:

Reduce supply: (e.g., destroy crops from which illicit drugs are derived or interrupting drug shipments). Tried for years, this is expensive, tends to cause an escalation of violence and may not be cost-effective. It does not address the drivers of the supply side: poverty, corruption, and the need for foreign currency in the supplying countries.

Raise prices: are effective in reducing the use of legal substances such as cigarettes. As with supply reduction it reduces access to the substance. Selling a substance only in large quantities also reduces access by increasing the price – for instance, in Canada cigarettes are sold only in packets of 20 or more. Pricing is particularly effective in limiting consumption among youth, who generally have less disposable income. But there are limits: a problem with legalized cannabis is that the price is so high that the lower-priced black market is not extinguished. And tobacco manufacturers have bypassed legislation on the quantity of cigarettes by marketing cigarillos to young people. As these are not technically cigarettes, they can be sold singly. The price of illegal substances is outside legal control, although reducing supply reduction drives prices up. Patterns of consumption of illegal substances are generally dictated by their street prices.

Reduce demand: this focuses on the other side of the equation. Education and information, community programmes, or legal penalties are used to discourage people from seeking drugs. Research suggests that these work best for those who are least dependent on drugs, but are less effective in the high risk population.

Prevention in Clinical Practice

Clinicians contribute to the health of the population when they intervene appropriately to:

  • promote health,
  • prevent disease,
  • reduce the duration or severity of illness,
  • reduce disability and handicap.

The main types of preventive intervention in clinical practice are shown in Table 8.2.

Table 8.2 Types of clinical preventive intervention

Type of intervention Examples from the recommendations of the U.S. Preventive Services Task Force*
Counselling Tobacco cessation for smokersDietary counselling for people with hyperlipidemia and other diet-related risk factors for chronic diseaseCounselling on breast feeding for pregnant women
Screening Hypertension in adultsChlamydial infection in sexually active women under 25Colorectal cancer in adults aged 50 to 70
Immunisation Routine immunisation in childhoodSpecific immunisations for people at risk due to work or travel
Pharmacoprophylaxis Ocular topical medication for newborns to prevent gonococcal ophthalmia neonatorumDiscuss the use of tamoxifen or raloxifene with women at high risk for breast cancerFolate supplements for before and during early pregnancy to prevent neural tube defects

*Note: Task Force recommendations are updated continually, so may have changed.

The evidence base for clinical preventive practice

Every day the popular and scientific media are filled with new health recommendations; the challenge is to decide which are effective. For this, the methods of evidence-based medicine are useful. A number of credible agencies undertake systematic reviews to propose clinical preventive guidelines that are available online:

Because different working groups use different notations to summarize the strength of the evidence, an international working group proposed the GRADE system of classification. This rates recommendations for or against an intervention as weak or strong depending on the balance of risk and benefit, while the underlying quality of evidence for this conclusion is rated as high, moderate, low, or very low ( ).25, 26

The Canadian Task Force on Preventive Health Care

North Americans used to view an annual physical examination as essential for maintaining health. The annual check-up was promoted by insurance companies in the 1920s and later by the American Medical Association in the 1930s and so became part of the collective medical creed. It consisted of a head-to-toe physical examination and the use of whatever tests were available: blood count, urine glucose and protein, chest X-ray ECG and, more recently, CT scans, and MRIs.

When Medicare began in Canada and everyone could have a government-funded annual physical examination, provincial ministers of health realized that the annual physical would be very expensive, that its components varied considerably, and that some were of questionable value. In 1976, a conference of Deputy Ministers of Health established a Task Force on the Periodic Health Examination, chaired by Dr. Walter O. Spitzer, to determine what should be provided in the annual physical. Spitzer brought together epidemiologists, family physicians, general paediatricians, internists, and a psychiatrist. Experts in the topics under study assisted in assembling evidence for the effectiveness of preventive procedures; the evidence was then assessed by others without particular expertise in the topic. For this, the Task Force established guidelines for searching the available evidence, assessing its quality, and expressing judgements in simple terms, thereby laying the foundations of what has now become known as evidence-based medicine. A Task Force declaration that not enough evidence was available became a stimulus to research.

The central recommendation of the Task Force’s first report in 1976 was to abandon the annual check-up altogether. Because of this, it changed its name to the Canadian Task Force on Preventive Health Care. The report also recommended when and how to use a series of preventive interventions, including counselling, screening, chemoprevention (e.g., vitamin and micronutrient supplementation), and immunisation.

The Canadian Task Force Report became respected around the world. A few years later the United States set up its own Task Force on Preventive Care. The Canadian and U.S. groups collaborated on a series of revisions and new topic reports. Even though the two groups studied the same evidence, their recommendations sometimes differed, reflecting differences in culture and context (see Chapter 14). As new evidence accumulated recommendations were updated until a second full report appeared in 1994. It was presented in a large red book, fondly known as “the red brick”. This received updates until 2006. Lack of funding caused the Task Force members to resign in 2005, but it was reformed in 2010 and continues to update its recommendations.

A major obstacle facing the Canadian Task Force is its lack of influence over the health care system, so that, while its guidelines are appreciated, their implementation is hampered by lack of incentives and the difficulty of changing established practice patterns and professional roles. In recent years changes in the system have improved the conditions for implementation. Developments in remunerating physicians mean that they are more likely to be rewarded for practising prevention. Also, the expansion of the multidisciplinary approach to care is likely to favour preventive practice.

A challenge is posed by the overwhelming amount of evidence and the recommendations of systematic reviews of therapies (such as the Cochrane Collaboration27) are not always followed, and proven therapies may not be applied in patient care. Studies in the 1990s evaluated ways to encourage clinicians to follow evidence-based guidelines. The results were assembled to produce taxonomies of behavior change techniques and to guide users in selecting the best approach for their purpose, whether changing clinician or patient behaviors, or institutional policies.28, Table 1; 29 Michie’s Theoretical Domains Framework outlined ways to encourage clinicians to adopt evidence-based practice guidelines.30 This was later adapted in the Consolidated Framework for Implementation Research to promote understanding of what works where and why, in different contexts.29 And a Behavior Change Wheel portrayed a range of strategies a clinician could follow in altering patient health behaviors. Rotating sectors on the wheel allow the user to align situational influences on behavior with potential interventions and with ways to deliver the interventions.31, Figure 1

Implementing preventive practice

When considering prevention in a clinical setting, we tend to think only of the interaction between a clinician and a patient, but this interaction does not occur in isolation. It lies at the centre of a set of influences and constraints on the patient and clinician, illustrated in Figure 8.4. Some factors are intrinsic to patients or physicians, others are extrinsic, related to the determinants of health or to the organisation of services. The numerous influences on prevention mean that there is no single solution to improving preventive practice.32 Positive attitudes of clinicians and their staff—and knowledge of the evidence for the effectiveness of prevention—are essential, but there are practical steps a clinician can take to modify features of the practice setting:

  • Develop an office system to promote the practice of prevention, as described in the next section
  • Implement continuous quality improvement, as described in Chapter 13;
  • ensuring that the practice setting promotes health (e.g., make sure the location is easily accessible on foot or by public transport and is accessible for people with physical handicaps; provide appropriate waiting-room reading material; provide no soft drinks or junk food outlets or vending machines);
  • Advocating for the health of the practice population and promote equity and high quality preventive care oriented towards the needs of the population. Clinicians who teach should ensure that their teaching addresses population needs.

Figure 8.4: Influences on clinical practice (adapted from Walsh & McPhee23)
Figure 8.4: Influences on clinical practice (adapted from Walsh & McPhee33)

Office systems for improving prevention in practice

Within a health care setting, a range of tools can help remove obstacles to preventive practice.34  They include providing cues for clinician action as well as ways to motivate and educate patients. Here are some types of tools that can improve preventive practice.

  • Chart or computerized reminders for clinicians: can indicate that patient has a specific risk behavior or is at risk for a specific illness and can track interventions and results. The placement of stickers must respect patient confidentiality;
  • Reminders for patients: mail, email or telephone patients when an intervention is due;
  • Visual prompts in office: for example, posters showing recommended interventions by age group;
  • Health risk appraisal: questionnaire and physical measures of health risks that inform the patient of their risk of selected diseases.35 Should be used in context; may be completed by patients as they await their appointment;
  • Patient information and patient-held records give the patient ownership of care.
  • Preventive prescriptions: these set out the objective to be achieved (negotiated with the patient), date for follow-up, and information about the changes to be made. A prescription reminds the patient what he has agreed to do.

Counselling David Richards

Having asked about David’s risk behavior, Dr. Rao puts a sticker on David’s chart as a reminder that he should be counselled on his risk factors. He asks David to see Nurse Jennings, who asks more about his use of tobacco and marijuana. David is reluctant to change his smoking: he doesn’t feel that it is doing him any harm. Nurse Jennings advises that his cough may be related to smoking and gives David a leaflet specially written for young people about smoking. Similarly, David feels his marijuana intake is not a problem: he thinks he can drive after a joint, which he can’t after alcohol. His friends smoke marijuana without apparent problems. Nurse Jennings, having completed the first 3 A’s of counselling (Ask, Assess, Advise) begins to plan how she can Assist and what she can Arrange to reduce David’s risks.

Changing behavior

From quitting smoking to taking one pill a day, many preventive and therapeutic interventions require patients to change their behavior, so that understanding the process of behavior change is essential for the clinician who wants to maintain or improve patients’ health.

Chapter 2 reviewed some theories of how health behavior is shaped. Prochaska and DiClemente combined a number of these to develop their “Transtheoretical model” of behavior change, and this is particularly useful in clinical encounters.36, 37 The model describes the stages through which a patient typically passes in adopting a new behavior, and identifies factors that may motivate or impede such progression. Using the transtheoretical model, a clinician can diagnose the patient’s change status and can offer “stage-appropriate” support for advancing through the stages.

The Stages of Change model states that at any time, for any behavior, a person is in one of the following stages of behavior change:

  1. Precontemplation: The person is not intending to change behavior (e.g., they have no interest in quitting smoking). For practical purposes, the time horizon is defined as not planning to change within the next six months.
  2. Contemplation: Although the person has not begun to change the behavior, he is thinking about it and intends to do so within the next six months (e.g., has at least talked to his doctor about stopping smoking).
  3. Preparation: The individual has now taken practical steps to do so (e.g., has set a quit date).
  4. Action: The individual has changed his behavior within the past 6 months (e.g., has quit).
  5. Maintenance: The individual has kept up the new behavior for at least 6 months.
  6. Relapse: Patients often find it hard to maintain the new behavior and relapse. This may lead them either to abandon the idea of changing and revert to precontemplation, or else stimulate them to try again, and so re-enter the contemplation or even the preparation stage, illustrated in Figure 8.5.

Figure 8.5: Illustration of the Transtheoretical Model of Behaviour Change.
Figure 8.5: Illustration of the Transtheoretical Model of Behavior Change.

Table 8.3 shows how the clinician’s role varies according to the patient’s stage:

Table 8.3: Stages of change and how to manage them as applied to exercise (adapted from Zimmerman, Olsen, Bosworth38)

Stage Explanation Therapeutic goal Tips for the clinician
1. Pre-contemplation The patient doesn’t see a need to change:“My uncle was obese and hated exercise. He lived until he was 90.” The patient starts thinking about changing.
  • Encourage the patient to consider change.
  • Personalize health information: “A person like you has a one in five chance of developing diabetes.”
  • Highlight any symptom that might be related to the behavior. Express concern, but avoid scare tactics.
  • Get the patient on a positive train of thought: “What would you see as the advantage of changing?”
2. Contemplation Thinking about change; weighing the costs and benefits: “I know I should, but it would take too much time.” The patient evaluates the benefits and barriers in a balanced fashion.
  • Ask patient to list benefits of, and barriers to, change. Ask for solutions, one barrier at a time. Explore ambivalence.
  • Encourage the patient to consider planning for a change. Push gently – rather than “you should try this,” say “some people find it helpful; you might too.”
3. Preparation Making small changes:“I’ve bought a pair of jogging shoes, but…” The patient develops a plan for change.
  • Encourage action. Put the patient in touch with programmes that can help them.
  • With their permission, engage the patient’s family or friends in supporting the change.
  • Ask about setting a precise date for change.
  • Help invent strategies for handling challenges the patient will face.
4. Action Taking definitive action: “I went jogging this morning.” The patient puts the plan into action.
  • The physician’s role is to supply encouragement and support.
  • Congratulate and encourage small successes.
  • Ask about problems encountered and review solutions. Schedule follow-up visits.
5. Maintenance Maintaining new behavior: “I’ve been exercising regularly for about 6 months now.” The new behavior becomes “normal.”
  • Continued encouragement.
  • Ask about what the patient will do if tempted to relapse.
6. Relapse “The weather got bad and I just couldn’t continue.” The patient re-engages in the process.
  • Ask about lessons learned from previous change.
  • Reformulate failure into partial success.
  • Remind patient that relapse is a normal part of the process of change.

Understanding the process of behavior change avoids “blaming the patient” for not adhering to recommendations. Clinicians who feel frustrated that a patient is not changing should ask themselves if their diagnosis of the patient’s stage of change was correct, and if their intervention was stage-appropriate. Note that counselling can be an opportunity to learn from patients. The clinician can ask patients about the tricks they used to make and maintain the change and then pass these ideas on to other patients in similar situations.

More stages of change

Since its original publication, the transtheoretical model has been refined. The following figure compares the original to a later adaptation by Weinstein.39

Figure 8.6: Two models of behaviour change and the clinician’s role.
Figure 8.6: Two models of behavior change and the clinician’s role.

The arrows indicate that patients can progress through the stages in either direction. The physician’s role is to help the patient progress to “Maintenance”.

Nurse Jennings continues to counsel David

Nurse Jennings opens her discussion with David by asking how he feels about his marijuana use and whether he has considered cutting down. He has not given this much thought. She gives him tips on the safe use of marijuana and alcohol (harm reduction), mentioning that the effects of marijuana can last for a day or more depending on the dose and that during this time driving can be impaired. She also talks about safer sexual practices. She asks about exercise. David mentions that he used to enjoy basketball in high school. Nurse Jennings encourages him to take it up again. Another patient told her that the local YMCA had openings for getting into sports. She gives David their number. Later, during lunch break, Dr. Rao and Nurse Jennings discuss if there is anything that can be done to help patients get as physically active as they should be to protect their health. Nurse Jennings says that it’s best when people can incorporate activity into their usual everyday tasks rather than having to make time for it. She asks Dr. Rao if it they could put a sign on the elevator door encouraging people to use the stairs. Dr. Rao makes a mental note to use the stairs more often himself and thinks about what else the clinic can do to encourage healthy behavior.

Self-test questions

1. Name the stages of change and suggest how to recognize each one according to what patients say.

A patient might say
Pre-contemplation: The patient doesn’t believe that he is at risk and sees no need to change.
“My uncle never (always) did and lived until he was 90.”
Contemplation: The patient is aware of the risk and how to avoid it, but still lacks motivation to change. Typically weighing the costs and benefits.
“I know I should, but … ”
Preparation: The patient is beginning to make small changes, the plans are more concrete.
“I’ve bought a pair of jogging shoes (supply of chewing gum, a bus pass, recipe book…), but… ”
Action: Concrete plan with definite date in the near future.
“I’m starting tomorrow.”
Maintenance: The patient has made the change and is maintaining it, although it might not be fully integrated as “usual” behavior.
“I’ve been sticking to it for a month now.”
Relapse. After behaving differently for a time, the patient falls into his previous behavior patterns.
“I was doing well, but… ”

2. What are the major influences that determine if an intervention will be applied?

In clinical situation, some factors influence the clinician, others influence the patient and yet others influence both.
Patient factors:  personal factors, such as the patient’s education, health knowledge, and income.Physician factors: the physician’s training and technical expertise.Health care delivery system factors: the costs, risks, effectiveness and acceptability of the intervention itself.Situational factors: cues to action during the consultation influence intervention.(See Figure 8.4 adapted from Walsh and McPhee 1992)

3. What are the advantages and disadvantages of reducing population risk as opposed to targeting high-risk individuals?

Advantages of a population strategy

Population strategies aim at the roots of the problem. As such, they reduce illness in the whole population, including those at low- or average risk. In a number of conditions, the population at low- or average-risk produce more cases of illness than the population at high risk (for example, see Figure 8.2), so that a population strategy may prevent more cases than strategies aimed at high risk individuals.

A small change in the level of a risk factor in a population can result in a large change in outcomes.

By emphasising the upstream, situational causes of the problem rather than individual factors, population strategies reduce the likelihood that individuals will feel blamed for their behavior, and they provide a more sustainable outcome. Population strategies aid in making the desired behavior “normal”. This encourages its adoption. They also eliminate the need to screen and identify a “high risk” group. This means that people at low or average risk are not falsely reassured and people at high risk are not needlessly made anxious.

Disadvantages of a population strategy

The small benefit to most individuals can be outweighed by the risk of the intervention, even if this is also small. As an example of the risk of intervention, recommendations about reducing fat in the diet have led some mothers to feed their baby low-fat milk in the mistaken belief that this is good for the child, who actually needs full-fat milk.

The lack of obvious personal benefit can reduce acceptability to the individuals who make up the population, particularly among those who consider themselves at low risk.

There is a danger of increasing health inequities: resources may not be directed to people most in need. Unless specifically designed strategies are used, vulnerable people in most need of change are least likely to do so. When a general population strategy is used, it is often the more educated and informed who follow the recommendations, that is those usually at least risk.

Interventions that affect apparently healthy people are open to ethical questions and they may be hard to justify politically. Interventions that affect people who have not consented to the intervention can be seen as social engineering, which is unacceptable in a liberal society.

4. What are the basic values of a health-promoting approach?

According to the Ottawa Charter (see figure 8.3) the values of a health promotion approach are the following:

·      evidence forms the basis of agreements between programme and policy decision-makers;

·      health promoters analyze all possibilities and act within their jurisdiction;

·      there is a need for overall coordination of activity;

·      society as whole must take care of all its members;

·      interactions between people and their physical and social surroundings affect health and health behaviors;

·      social justice, equity, mutual respect and caring are necessary for health;

·      health care, health protection and disease prevention complement health promotion.

5. Give an example of a primary preventive intervention recommended in clinical practice.

Consultation of guidelines such as those produced by the US task force on preventive care produce a number of such interventions, such as counselling against the use of tobacco, counselling for the use of seat-belts, or prescribing folic acid to women wishing to become pregnant. Primary prevention refers to interventions that are offered before disease occurs.

6. Give an example of a primary preventive intervention that can be applied to a population.

A wide variety of primary preventive interventions have been applied to populations. Examples include passing laws on seat-belts and on bicycle and motorcycle helmets, as well as those restricting advertising, selling and consumption of tobacco products. Many municipal activities in regulation of housing, water supply and sewage, as well as programmes of food inspections also contain elements of primary prevention. Activities that promote healthy lifestyles, such as the construction of cycle paths and the offer of healthy cooking classes in impoverished areas are others.

Reflection Questions

1.   In your experience of clinical situations, what are the barriers to primary preventive practice?
2.   In your experience of clinical situations, what increases the practice of prevention?
3.   What information resources are available to clinicians to support the choice of intervention to reduce risk?


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