Care at the End of Life

Overview

What decisions do you need to make about care at the end of life?

You will face many hard decisions as you near the end of life. Those decisions will include what kind of care you'd like to receive, where you'd like to receive care, and who will make decisions about your care should you not be able to make decisions yourself.

No one knows when his or her time may come. So it's a good idea to spend some time planning what you want at the end of life. To be prepared:

• Decide what kind of health care you want or don't want. For example, you can decide whether you want CPR if your heart or breathing stops.
• Let others know what you've decided. Consider writing an advance directive that includes a living will and a medical power of attorney (also called a durable power of attorney). A living will is a legal document that expresses your wishes for medical care if you are not able to speak or make decisions for yourself. A medical power of attorney lets you to choose a health care agent. Your health care agent will have the legal right to make treatment decisions for you, not only at the end of your life but anytime you are not able to speak for yourself.
• Decide whether you'd like to donate your organs.

Will you have to choose between palliative care and treatments that might cure you?

One thing to think about is what type of medical care you want. Some people ask their doctors to do everything possible to keep them alive. This is called curative treatment. Others choose palliative care, which does not try to cure your illness or keep you alive longer. It looks at ways to make you more comfortable. For example, palliative care may include giving you medicines to help with pain or with the side effects from treatment.

You can have both types of treatment. You can get palliative care to help keep you comfortable, and you can take medicines or other treatments that might cure you.

But a time may come when you decide one is more important. You may choose to stop curative treatment if it is very clear that your illness can't be cured. If you choose palliative care only, you will still see your doctor and get excellent care. And if your condition changes, you can start curative treatment again.

Where would you like to be treated?

Another thing to think about is where you'd like to receive care. Some people check into a hospital. Others choose to be cared for at home or in a nursing home.

If you have only a few months left, you may choose to receive care through hospice. Hospice services are provided by a team of people that includes doctors, nurses, and volunteers. The team gives palliative care and emotional and spiritual support to people near the end of life and to their families. It also offers practical support like running errands or fixing meals. You can get hospice care in your home or in a hospice center, hospital, or nursing home.

What do you and your doctor need to know?

If you find out that you have a life-threatening disease or condition, talk with your doctor about the kind of medical care you'd like to receive. Ask a lot of questions about your illness and the treatments that are available. It can be helpful to have a friend or family member go to your appointments with you.

When you have decided whether you want palliative care or curative treatment or both, tell your doctor. Also, share your advance directive with your doctor.

How do you talk with your loved ones about your end-of-life choices?

It can be hard to talk with your loved ones about death, but it is important to discuss your choices while you can speak for yourself. Planning ahead will help you and your loved ones make hard decisions when the time comes.

Even though it might be awkward or uncomfortable, look for chances to talk about your end-of-life choices. For example, you could bring up the subject while you are making out your will. Or you could talk with loved ones after a visit to the doctor. Family gatherings are another place to make time to discuss your plans with loved ones.

Whatever you decide and whenever you decide to talk with loved ones, be sure to put your wishes in writing. You can always change your mind if your condition or your wishes change.

Health Tools

Health Tools help you make wise health decisions or take action to improve your health.

	Decision Points focus on key medical care decisions that are important to many health problems.
	Should I have an autopsy done on my loved one?
	Should I receive artificial hydration and nutrition?
	Should I receive CPR and mechanical ventilation?
	Should I stop kidney dialysis?
	Should I stop life-prolonging treatment?

Frequently Asked Questions

Important Decisions

Many important decisions can be made about the care you want to receive at the end of life while you are active and able to communicate your wishes. By making arrangements in advance, valuable time can be used to spend time with loved ones.

Communicating your health care decisions

By completing an advance directive, which documents your health care preferences, you can help ensure your wishes will be respected if you become unable to communicate for yourself.

An advance directive can always be changed as your personal needs and goals change. Advance directives include:

• A living will, which is a legal document that expresses your wishes for medical care if you become unable to speak or make decisions for yourself. It allows you to keep control over your medical treatment decisions at the end of life. Check the laws governing living wills in your state. When considering some of the more difficult end-of-life decisions, it may help to think about what kinds of medical procedures you would or would not want.
• A medical power of attorney (or durable power of attorney for health care), which allows you to legally appoint a health care agent (also called a health care proxy) to make medical treatment decisions for you, not only at the end of your life but any time you are unable to speak for yourself. You can and should make decisions about your medical treatment for as long as you are able to make and communicate them. But when this is not possible, your health care agent can use both the written information in your living will as well as what he or she knows about you personally to make decisions about your medical treatment.

For more information on choosing a health care agent and writing an advance directive, see:

• Writing an Advance Directive.
• Choosing a Health Care Agent.

Organ donation

Organ donation is another important decision to consider at the end of life. Many people need organ transplants because of medical conditions such as kidney failure, cornea disease, or heart failure. After your death, you may be able to donate certain organs depending on their condition. Talk to your doctor about whether your illness allows you to be an organ donor.

If you choose to donate, your organs may be distributed to one or more people, based on blood and tissue type, the severity of the recipient's medical condition, how long the recipient has been waiting, and geographical location.

If you are interested in donating, you can indicate this on an organ donor card, a witnessed document that states your desire to donate your organs. On this card, you can specify which organs you wish to donate, or you can choose to donate any organ that is needed at the time of your death. Many states allow people to designate on their driver's licenses their wishes regarding organ donation.

People under the age of 18 must have a parent's or guardian's consent to donate organs.

Even if you complete a donor card or indicate your wishes on your driver's license, it is important to discuss your decision with your family. After your death, your family may be asked to give consent prior to donating your organs. For this reason, it is important to involve your family.

Organ donation will not disfigure your body, nor will it interfere with your funeral, including plans for an open casket funeral. You and your family will not be responsible for the costs associated with organ donation-those costs are paid by the person who receives the organ.

Estate planning

As you make end-of-life decisions, an attorney can advise you on how best to organize your estate so your family can handle your affairs after your death. Also, a financial planner or social worker may be available in your community or through a local hospital or hospice program. If your finances are limited, some attorneys and accountants offer services at a reduced rate or at no cost (pro bono).

Estate planning may include:

• Writing a will. If you already have a will, it may need to be updated. If you do not make your wishes known in a will, your state law may dictate what happens to your property when you die. Generally, property is distributed to a spouse, to children, or if there is no spouse or children, to other relatives. If no relatives can be found, your property may be taken by the state. Consider appointing a person to oversee your property after your death. This person is called an executor. After you write your will, keep it in a safe place, and let your executor and close family members know where it can be found.
• Appointing someone to make financial decisions for you in the event you are unable to do so.
• Choosing one or more people to care for your minor children (guardianship). A guardianship is a legal arrangement in which an adult has the court-ordered authority and responsibility to care for a child under the age of 18 or for an incapacitated adult.
• Ensuring your records are in a safe, accessible place. Documentation of a life insurance policy, pension, retirement account, or annuity should be stored in a safe place, along with bank account information, deeds to real estate, or investment information. Close family members, the executor of your estate, and your attorney should know where this information is kept.

Choosing the care you want

When you are diagnosed with a terminal illness, it can be difficult to know whether you should focus on treatment to cure your condition or prolong your life or on palliative care to relieve pain and maintain comfort. For more information on treatment to relieve pain and maintain comfort, see the topic Palliative Care.

Several factors may impact your decision about the kind of care you want, including:

• Your illness. If you are diagnosed with a serious illness, curative treatment options may be available. Certain diseases, such as skin cancer, testicular cancer, and cervical cancer, are often cured with appropriate medical treatment. Other serious illnesses, such as diabetes and AIDS, cannot be cured but can be managed successfully for many years. And some illnesses are more aggressive and life-limiting.
• Your treatment options. Many medical treatment options offer the chance of curing a disease with little effect on the quality of your life. Other treatments may prolong your life but may be associated with side effects that drastically decrease the quality of your life.
• Your age and other health conditions. Older people with multiple health problems may be more likely than healthier younger people to choose care that focuses on keeping them comfortable rather than keeping them alive as long as possible.

For more information on making the decision to stop curative treatments, see:

Should I stop life-prolonging treatment?

Talking to your doctor

When you are diagnosed with a terminal disease or condition, it is important to communicate your preferences and concerns clearly with your doctor. Likewise, you should expect your doctor to communicate openly and sensitively with you and your loved ones. Your doctor can provide information, answer questions, and advise you. But the decisions are yours.

Gather as much information about your disease as possible. If you do not understand what is being said, ask questions until you do. It may be helpful to write down your questions prior to your appointment. Important questions to ask your doctor include:¹

• What is my diagnosis?
• What are my treatment options? What are the side effects of these treatments?
• What do you think will happen if I choose not to treat my illness?
• How long do you think I have to live?
• How soon do I need to make a decision about which treatment to use (or to not use)?
• How will my illness and care affect my loved ones?

Explore all of the possibilities with your doctor and your loved ones. Some days, you will feel better emotionally and physically than others.

There may be times when you have difficulty understanding your doctor. Sometimes good communication is difficult, especially when end-of-life issues are the focus. You may be frustrated if you feel your doctor is not communicating openly with you or is avoiding your questions. Understanding why these problems sometimes occur may decrease your frustration and help you to think of ways to improve communication.

Communicating bad news to a person is always difficult. Your doctor may have provided care to you for a long time, and perhaps he or she feels very close to you. Remember that your doctor is human, and although you want to know as much as possible about your illness, your doctor cannot predict exactly how and when your life will end. A recent study showed that the better a doctor knows a patient, the more likely the doctor is to overestimate the patient's life expectancy and to delay end-of-life care.² Doctors may overestimate survival time because they do not want to believe that a patient they feel close to is not doing well. It may be helpful to see another doctor who can give you a second medical opinion.

Some doctors have a difficult time talking to their patients about issues at the end of life because they view death as their own failure. Doctors have been trained to cure illnesses and save lives, so some may feel they have failed their patients. Communicate your goals clearly and directly.

Until recently, medical schools in the United States did not teach about care at the end of life. As a result, many doctors may have difficulty talking to dying people. As more medical schools address care at the end of life in their curriculum, many doctors will learn to communicate more skillfully with their dying patients. Seeking help from others (such as a support group for people with life-limiting illnesses) may help you through this difficult emotional time.

Some doctors feel they are not providing the best possible care unless they offer the most technologically advanced treatment, such as mechanical ventilation. Some doctors fear they may be sued for malpractice if high-tech treatments are not offered, even in situations in which death is certain. The best way to avoid unwanted medical treatments at the end of your life is to think about what treatments you do and don't want, communicate your thoughts clearly and directly, and record your wishes in writing through an advance directive.

Your illness may prevent you from feeling well enough to talk to your doctor. Also, your doctor may explain the situation in terms that are difficult for you to understand. You may find it helpful to take along a family member or a friend to your medical appointments. Another person can help you listen as your disease and treatment options are explained to you. Don't hesitate to take notes, if this is helpful for you. And it's also okay to ask your doctor to slow down, if needed.

Don't be afraid to raise spiritual issues with your doctor, especially if you have religious beliefs that affect your treatment choices. Although you cannot expect your doctor to resolve your spiritual issues, discussing them may help your doctor better understand your emotional needs.

Limited time with a doctor has always been a concern of patients (and doctors). Prepare for your appointments by writing down your questions and concerns and taking this paper to your appointment. This will help you remember to address the important issues. If a family member or friend is going with you to your medical appointment, rehearse with that person what you want to cover during your appointment.

As your illness progresses, you may become too ill to continue seeing your doctor at a clinic or to talk on the telephone. If you wish to be at home as you die, it is helpful to designate only one family member or friend to communicate with your doctor. Choosing one reliable person to relay messages will help avoid the confusion caused by several people trying to communicate with your doctor.

Aggressive life-sustaining medical treatment

Discuss with your loved ones and doctor how you feel about life-sustaining treatment.

Tough choices include whether you want cardiopulmonary resuscitation (CPR) performed on you if your heart stops. If you stop breathing, a ventilator or respirator may be used to mechanically breathe for you. Although mechanical ventilation can prolong your life, your remaining days may be spent in the intensive care unit of a hospital connected to life-support equipment. You may not be fully alert and may not be able to speak.

Talk to your doctor about your illness, specific treatment options, and chances for recovery. Your family is an key part of this process. Discuss your options with them and clearly state your wishes. Some people who are facing death have strong and definite feelings about CPR, and the decision for or against life support may be easy. For other people, this decision is extremely difficult.

For more information on this decision, see:

Should I receive CPR and mechanical ventilation?

Artificial hydration and nutrition

Another important treatment issue to consider is whether you want intravenous, or IV, lines or feeding tubes to be used if you are no longer able to take food or fluids by mouth. This is known as artificial hydration and nutrition. An IV is a needle placed in your vein through which fluids, liquid nutritional supplements, or medicines can be given. A feeding tube can be either a tube inserted into the stomach through the nose (nasogastric, or NG, tube) or a tube surgically inserted through the abdomen into the stomach (gastrostomy or PEG tube, or g-tube). As with an IV line, liquid nutritional supplements, fluids, or medicines can be given through a feeding tube. A third form of artificial hydration, hypodermoclysis, involves the injection of fluids directly into tissues beneath the skin (subcutaneous).

Changes in your body in the final weeks of life reduce your need for food and water. You will likely not be thirsty or hungry. You may feel better without artificial hydration or nutrition.³

Talk to your doctor if you are considering artificial hydration and nutrition. Making a plan for IV fluids and feeding tubes early in the course of your illness may be helpful if you are faced later on with the decision to pursue or forgo these treatments. Remember to communicate your wishes clearly with your family and your doctor.

For more information on this decision, see:

Should I receive artificial hydration and nutrition?

Kidney dialysis

Deciding when to stop kidney dialysis can be a difficult decision for people with kidney failure. A person with kidney failure needs dialysis or a kidney transplant to sustain life. Kidney failure often occurs after kidney damage has been present for 10 years or more. It usually is caused by a chronic disease, such as chronic renal disease or diabetes, that slowly damages the kidneys and reduces their function over time.

Although dialysis sustains life, it is not a cure for kidney failure. In the United States, 1 out of 4 people with kidney failure chooses to stop dialysis and receive palliative care only.⁴ Having kidney disease means making difficult choices. Many people with kidney failure live active, productive lives while having regular dialysis treatment. But others do not feel as healthy and struggle with the complications of dialysis.

For more information on this decision, see:

Should I stop kidney dialysis?

Where to Receive Care

Deciding where you will receive care as your illness progresses can be challenging, but planning now for your care can decrease your anxiety later on. Talk to your loved ones about the type of care you would like to receive at the end of your life. Discuss their expectations as well as your wishes, care needs, finances, and the needs of your family. Your choice may change as your illness changes.

A study of seriously ill patients in hospitals and their family members showed that the most important elements of end-of-life care were:⁵

• Trust and confidence in the doctor who is treating the patient.
• Having the option of not being on life support.
• Effective communication between the patient, the patient's family, and the doctor.

Several care options are available, including hospice, home care, nursing home placement, or care from an assisted-living facility. A study of the last place of care for people at the end of life found that 69% of people were in a hospital or nursing home for their last place of care, and 31% of people were at home for their last place of care.⁶ The same study found that patients and their families were the most satisfied with home hospice care.

Hospice care

As death nears, you may choose to receive help and support from hospice. Hospice care focuses on using palliative therapies exclusively to manage pain and other symptoms when there is no cure for your condition and death is anticipated within the next six months. Part of this care is keeping you as alert and comfortable as possible in a familiar environment, surrounded by your family and friends. When you choose hospice care, you agree to forego curative and life-sustaining treatments. But you can change your treatment plan at any time.

Hospice care is provided by a team of health workers, including nurses, social workers, volunteers, counselors, and personal care assistants. Your doctor can continue to direct your care and work closely with you and the hospice team. Hospice care most often occurs at your home, although it can be given in a nursing home, a hospital, or a hospice center. If you remain at home, the hospice team supports your family in their caregiving. And 'family' is not limited to your spouse (or partner) or blood relatives. Friends from your workplace, church, community, or neighborhood may be considered part of your family.

Hospice care seeks to relieve physical symptoms and address your emotional, social, and spiritual needs, as well as the needs of your loved ones. Hospice offers a chance to address difficult but normal concerns that you and those you love may have about death and dying, such as pain, unresolved issues, and caregiving needs. If you choose, the counseling and support services that hospice provides will offer opportunities to work on mending important relationships and to explore spiritual issues.

The hospice team is available to help with advance directive forms and with legal and financial affairs. Also, hospice staff can answer questions about treatment and what to expect during the dying process. Assistance is also available to help with physical needs, such as bathing and pain control.

Hospice services are a benefit of many private health insurance policies. Check your health plan for specific information about hospice coverage. Also, if you qualify for Medicare benefits, hospice services are covered through the Medicare hospice benefit.

For more information on choosing hospice, see the topic Hospice Care.

Home care

You may choose to remain at home as your illness progresses, especially if you have a large support network of family and friends who can help with your care. Another factor in making this choice may be whether you have the financial resources to hire trained caregivers to help your family with your care. Remaining at home in a familiar environment, surrounded by loved ones, may be the best care option in these circumstances.

Community services are available to help your family provide care for you at home. Talk to your doctor about receiving help from hospice or a nursing agency. Develop a list of people who can help your family with your care, including people from work, church, or community groups. In many larger communities, private case management practices are available to help find and coordinate the services you may need in order to be cared for at home.

Nursing home care

You may consider receiving care in a nursing home if you are unable to remain at home during your illness. A nursing home also may be the best option if you need more skilled care than can be provided at home, or if a family member is unable to care for you because he or she is ill, disabled, or elderly.

Information on choosing a nursing home may help you as you decide whether nursing home care is the best choice for you.

Assisted-living facilities

Assisted-living facilities are a popular alternative to nursing homes for people who can provide the majority of their own care. Assisted-living facilities generally offer individual rooms with limited cooking facilities in each unit. Residents usually meet in a dining room for meals. Housekeeping and laundry services, social activities, and access to a nurse are generally provided.

Some assisted-living facilities are connected to a nursing home. In these facilities, you can transfer from the assisted-care facility to the nursing home when you are no longer able to provide your own care. Get written information from the assisted-living facility about what is expected if your condition gets worse and you are no longer able to care for yourself. Many assisted-living facilities require that the resident move to a nursing home or hire a personal caregiver if skilled care is needed.

Regulations for assisted-living facilities vary from state to state.

The Dying Process

If you are dying or are caring for a dying loved one, you may have questions and concerns about what will happen physically and emotionally as death approaches. The following information may help answer some of these questions.

Signs of approaching death

The dying process is as variable as the birthing process. The exact time of death cannot be predicted, nor can the exact manner in which a person will die. But people in advanced stages of a terminal illness experience many similar symptoms as they approach the end of life, regardless of their illness.

Several physical and emotional changes occur as death approaches, including:

• Excessive sleepiness and weakness as periods of wakefulness become shorter and overall energy declines.
• Breathing changes, such as periods of rapid breathing alternating with short episodes when breathing stops.
• Visual and hearing changes, such as seeing people or scenes that others do not (hallucinations).
• Decreased appetite as your metabolism slows and you no longer have the same interest in food.
• Urinary and bowel changes, such as dark or red urine and hard stools that are difficult to pass (constipation).
• Temperature changes, such as running a high temperature or feeling very cold.
• Emotional changes, such as becoming less interested in the outside world and being less socially involved with others.

Dying people may also experience symptoms specific to their illness. Talk to your doctor about what to expect. Also, if you have chosen to receive hospice care, the hospice team is available to answer any questions you may have about the dying process. The more you and your loved ones know, the better prepared you will be to cope with what is happening.

Pain

Palliative care can help you to feel relief from physical symptoms related to your illness, such as nausea or difficulty breathing. Pain control and symptom control are important parts of managing your illness and improving the quality of your life.

Whether a person suffers from physical pain in the days before death often depends on the illness. Some terminal illnesses, such as bone or pancreatic cancer, are more likely to be accompanied by physical pain than others.

Pain and other symptoms can be so feared that a person considers physician-assisted suicide. But pain associated with the dying process can be managed effectively. Any pain should be reported to your family and your doctor. Many medicines and alternative methods (such as massage) are available to treat the pain associated with dying. Do not hesitate to ask for help. Have a loved one report your pain if your illness prevents you from communicating with your doctor.

You may want to protect your family from your suffering. But it is important to tell them if your pain level is not tolerable so they can tell your doctor right away.

Spirituality

Spirituality refers to a person's sense of meaning and purpose in life. It also refers to a person's relationship to a higher power or an energy that gives life meaning.

Some people do not think of spiritual matters often. For others, spirituality is a part of daily life. Facing the end of your life may cause you to confront your own spiritual questions and issues. Organized religion provides comfort to many people as they face death. Others may find solace in exploring nature, through community involvement, by strengthening existing relationships, or by developing new relationships. Think about what provides comfort and support to you. What questions and concerns do you have? Don't hesitate to ask for support from friends, family, hospice, or spiritual advisors.

Caring for a dying loved one

The dying process can be a time for growth. It offers the dying person and his or her family and friends a time to mend relationships, share memories, and say their good-byes. If you are a caregiver, it is important to communicate openly with your dying loved one. Also, seek support from others and take care of yourself so you don't become physically and mentally exhausted.

After Death

Autopsy

An autopsy is the thorough examination of a body after death to help determine how and why a person died. Autopsies are not performed as frequently as they have been in the past, especially when the death is expected.

An autopsy is often not needed to determine the cause of death when a person dies of a disease or condition that had been diagnosed. If a diagnosis and cause of death is unclear, some families may wish to have an autopsy done. This can provide family members with information about diseases or conditions that they also may be at risk for developing.

Family members should find out the cost of an autopsy before one is arranged. For more information, see the topic Autopsy.

Should I have an autopsy done on my loved one?

Grieving the death of a loved one

Grief following a loved one's death is a normal, healthy reaction. It is a gradual process that helps people begin to accept their loss and to adjust to life without their loved one. It often takes 2 years or more to go through the most intense emotions of the grieving process. Although the pain of grief fades over time, the sense of loss after a loved one's death never completely goes away.

People experience grief physically and emotionally in their own ways. After a death, it is common for survivors to wonder if their grief is normal. Shock, denial, anger, and guilt are all common reactions after the death of someone close. For example, a person may feel angry toward other family members, a higher being, or even at the person who died. Or survivors may feel guilty because their loved one had a long illness and they are relieved that the death finally occurred. These all are normal reactions to loss.

Survivors need to be patient with themselves, and they need to seek help and support from others. Grief counseling may help some people who are having difficulty with the grieving process.

For more information about surviving the death of a loved one, see the topic Grief and Grieving.

Other Places To Get Help

Organizations

Related Information

• Choosing a Health Care Agent
• Chronic Pain
• Grief and Grieving
• Hospice Care
• Writing an Advance Directive

References

Citations

1. Tobin DR (1999). Coming to terms. In Peaceful Dying: The Step-by-Step Guide to Preserving Your Dignity, Your Choice, and Your Inner Peace at the End of Life, pp. 71-86. Reading, MA: Perseus Books.

2. Christakis NA, Lamont EB (2000). Extent and determinants of error in doctors' prognoses in terminally ill patients: Prospective cohort study. BMJ, 320: 469-473.

3. McCann RM, et al. (1994). Comfort care for terminally ill patients: The appropriate use of nutrition and hydration. JAMA, 272(16): 1263-1266.

4. Cohen LM, et al. (2003). Practical considerations in dialysis withdrawal. JAMA, 289(16): 2113-2119.

5. Heyland DK, et al. (2006). What matters most in end-of-life care: Perceptions of seriously ill patients and their family members. Canadian Medical Association Journal, 174(5): 1-9.

6. Teno JM, et al. (2004). Family perspectives on end-of-life care at the last place of care. JAMA, 291(1): 88-93.

Other Works Consulted

• Billings JA (2008). Care of dying patients and their families. In L Goldman, D Ausiello, eds., Cecil Medicine, 23rd ed., pp. 11-16. Philadelphia: Saunders Elsevier.

• Byock I (1997). Dying Well. New York: Riverhead Books.

• Byock I (2004). Four Things That Matter Most: A Book About Living. New York: Free Press.

• Collins JJ (2006). End-of-life care for pediatric patients. In FD Burg et al., eds., Current Pediatric Therapy, 18th ed., pp. 242-245. Philadelphia: Saunders Elsevier.

• Kliegman RM (2007). Grief and bereavement. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 18th ed., pp. 206-208. Philadelphia: Saunders Elsevier.

• Liben S (2007). The care of children with life-limiting illness. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 18th ed., pp. 200-206. Philadelphia: Saunders Elsevier.

• Rabow MW, Pantilat SZ (2008). Care at the end of life. In SJ McPhee et al., eds., Current Medical Diagnosis and Treatment, 47th ed., chap. 5, pp. 67-84. New York: McGraw-Hill.

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