Most of the older patients that come under the care of nurses are fully able to make health care decisions for themselves. For these patients, the role of the nurse is to assure that the patient's wishes are correctly elicited and met. As nurses, our Code of Ethics mandates that we respect and promote patient autonomy (American Nurses Association, 1985).
There are instances, however, when nurses care for patients whose decisional capacity fluctuates, is unclear, or whose capacity is completely and permanently impaired. Nurses encounter such patients in a variety of settings: hospital emergency rooms, following surgery, in nursing homes, and in home care. There are times when it become particularly important to accurately determine a patient/ s decision-making capacity, for example when signing a consent to a procedure or executing an advance directive (durable power of attorney for health care[health care proxy]) and /or living will).
Nurses can make a valuable contribution to assuring that the informed consent process is accurately met (Davis, 1989). Yet, in general, nurses and other health care professionals have little training in assessing decision-making capacity. Unfortunately, there is no "gold standard" for capacity determination. Standardized mental status assessment tests (e.g., MMSE, SPMSQ), often administered by nurses, are insufficient in and of themselves to measure whether a patient has the ability to make a specific health care decision. Impaired cognition, inability to follow a simple direction or do simple mathematics, and memory loss are not in and of themselves signs of incompetence and incapacity that would bar an individual from making all health care decisions.
On the other hand, by virtue of the type of encounters nurses have with patients, nurses are particularly knowledgeable about patients' behaviors, mood, and firmly held beliefs. Nurses' observations and clinical judgments are highly germane to a determination of capacity. It is precisely this type of information and documentation that can be most helpful in determining the extent to which a patient can make a health care decision. Yet it is also true that these types of observation are often not elicited or seriously considered in the process of a capacity determination.
This article reviews the overall issue of decision-making capacity. The goal of the article is to increase nurses' knowledge and comfort in making a substantive contribution to the determination of whether an individual has the requisite capacity to make health care decisions. Specifically, the authors explore the difference between the legal standard of competence and the clinical determination of capacity, present the concept of decision-specific capacity, identify measures available to help in capacity determination and describe intervening and often reversible conditions that can impair decisional capacity. It suggests, also, how nurses can contribute to accurate capacity determinations.
DIFFERENTIATING BETWEEN COMPETENCE AND CAPACFTY
Competency to make health care decisions is a legal term; only a judge can determine competency. In general, to be considered competent, an individual must be able to comprehend the nature of the particular action in question and to understand its quality and its consequence. Adults are presumed to be legally competent unless there is evidence that the individual is unable to care for him /herself or to manage his/her affairs, or both. The law presumes that all adults are competent and that they have decision-making capacity (Applebaum & Grisso, 1988; Markson, Kern, Annas, & Glantz, 1994; New York State, 1991; Roth, Meisel, & Lidz, 1977). Not only is competence to make health care decisions presumed in law, it is usually assumed in day-to-day affairs, and the assumption is ordinarily a correct one (Meisel, 1989).
Capacity, on the other hand, is clinically determined, does not require a legal opinion, and stems from the notion of functional capability. Determination of incapacity is not a medical or psychiatric diagnostic category but rather rests on a clinical judgment of the type that an informed lay person might make (President's Commission, 1982). The determination that a patient has sufficient decision-making capacity to consent to or refuse a particular treatment is based on observation of a specific set of abilities: 1) the patient appreciates /understands that he/she has the right to make a choice; 2) the patient understands the medical situation, prognosis, risks, benefits and consequences of treatment (or no treatment); 3) the patient can communicate the decision; and 4) the patient's decision is stable and consistent over a period of time (Roth, Meisel, & Lidz, 1977). Central to the concept of capacity is the fact that the patient's decision should reflect their values and preferences. It is "an individually appropriate choice" that reflects a patient's autonomous decision-making because it is evidence of the patient's "authentic self" (Zuckerman, 1994, p. 93).
The clinical approach has many aspects to recommend it over a (legal) competency determination. As opposed to the judicial approach, the clinical approach is characterized by simplicity, speed, convenience, access to experts, and family willingness to participate. It is less disruptive to health care decisions, maintains respect for patient privacy and is less emotional and upsetting to patients, family and staff (Meisel, 1989).
Clinical capacity determinations lack a standardized method despite the fact that assessment of capacity is a critical ethical event (Collopy, 1994). Capacity assessment has received minirnal attention in clinical practice (Collopy, 1994; Gerety, Chiodo, Kanten, Tuley, & Cornell, 1993; Mezey, Ramsey, & Mitty, 1994). Physicians, usually the health care providers responsible for making the ultimate determination of capacity, lack clear standards (i.e., a "protocol") by which to determine capacity (Searight, 1992). Other drawbacks to a clinical approach to capacity determination include: uncertainty about its legitimacy (Meisel, 1989) and lack of procedural protection and issues of liability (Meisel, 1989). In health care institutions with ethics committees, the value of the clinical approach depends heavily on the composition and skills of such committees (Meisel, 1989).
The President's Commission (1982) urged health care professionals to develop clear policies for capacity (and competency) assessment. Yet, few systematic methods of determining capacity exist (Applebaum & Grisso, 1988; Searight, 1992).
Every health decision does not require the same degree of decisionmaking capacity in order to make an adequate decision. As such, decision-making capacity is not an "onoff" switch. Rather, bioethicists as well as legal scholars suggest that capacity should be viewed in "taskspecific" rather than in general terms (Furrow, Johnson, Jost, & Schwartz, 1991). An individual may be capable of reforming some tasks adequately, i.e., have the capacity to make some decisions, but not others. This notion of "decision specific capacity" assumes that an individual has or lacks capacity for a particular decision at a particular time and under a particular set of circumstances. Most older people retain sufficient cognitive capability to make some, but not necessarily all, decisions (Miller, 1995).
Capacity is specific to the decision in question (Meisel, 1989, p. 180). Each determination of decisional incapacity focuses on a patient's actual functioning in a particular decision-making situation rather than simply on an individual's age or diagnosis (President's Commission, 1982). A universal view of capacity as either present or absent is not supported empirically or legally (Searight, 1992).
Thus, a patient may have impaired capacity but not lack capacity totally (Meisel, 1989). Rarely is incapacity absolute; even people with impaired capacity usually still possess some ability to comprehend, to communicate, and to form and express a preference (President's Commission, 1982). Since patients may be incapable of understanding some things but are capable of understanding others, it is necessary to be specific about what understanding must be deficient in order to deem the patient incapable of making a medical decision (Haddad, 1988; Meisel, 1989). Persons with dementing illness are often inaccurately assumed to be "globally" decisionally incapacitated (Gerety, Chiodo, Kanten, Tuley, & Cornell, 1993). Yet persons with mild to moderate dementia (MMSE 24 + 4.1) are clearly able to make some treatment decisions (Drane, 1985; Gerety, Chiodo, Kanten, Tuley, & Cornell, 1993).
The standard for deterrnining if an individual has sufficient decisional capacity to make a health care decision becomes more exacting as the risks associated with the decision become more significant. Decisions that have potentially dire consequences, for example, consenting to an amputation, require clearer evidence of capacity man a less complicated decision, for example, to choose to eat in one's room rather than go to the dining room. In the case of advance directives, the capacity needed to execute a living will is thought to be greater man mat needed to execute a health care proxy (Midwest Bioethics Center, 1996; Silberfeld, Nash, & Singer, 1993). To execute a living will a person must show evidence of understanding specific treatments such as DNR, respirators, etc., while to execute a health care proxy requires a person's understanding that they are asking /appointing someone (who is known, trusted, and aware of their wishes and preferences) to make decisions should the person become I unable to do so.
CONDITIONS THAT CAUSE HEALTH CARE PROVIDERS TO QUESTION A PERSON'S CAPACITY
When trying to sort out whether a patient has the capacity to make a specific decision, it is important to keep in mind that questions about decision-making capacity usually arise when a person's capacity fluctuates or when they evidence inconsistencies when making decisions. A ^ person's capacity to make a decision is much more likely to be called into question when the decision they choose to make is at variance with the recommendation of health care providers or with administrative rules. Capacity (and competency) is presumed as long as it is not questioned. People who look and talk "normal," remember what they are told, dress and act appropriately, appear to be in meaningful communication, i.e., "have their wits about them," are assumed to understand (Roth, Meisel, & Lidz, 1977).
Because decision-making capacity is not a "solid state" but rather, waxes and wanes, an important role of the nurse is to make sure that the person is in the best possible condition when asked to make a decision. One starts with die premise that the patient has decisional capacity until proven otherwise. Attempts should be made to treat reversible conditions that can temporarily cause decisional incapacity such as failure to correct visual and hearing deficits, acute illness, medication effect, fatigue and sleep deprivation, depression, etc. Alterations in physical functioning, such as aphasia or inability to perform ADLs, should not be construed as necessarily impairing cognition or decisional capacity.
For the patient with fluctuating capacity, the nurse is often in the best position to identify the times of day when the patient is most lucid. The patient's capacity should then be assessed during these "windows of lucidity" (Collopy, 1994). That is, persons should be assessed at the time they are the most capable (Kutner et al., 1991). A patient whose decision-making capacity fluctuates cannot be denied an opportunity to make decisions concerning medical care, even life-sustaining medical care, just because of the temporary absence of capacity (Furrow, Johnson, Jost, & Schwartz, 1991).
DETERMINING DECISION-MAKING CAPACITY (DMC)
No valid, standardized, straightforward method exists to determine DMC. In their classic work, Roth, Meisel, and Lidz (1977) describe four levels of "evidence" that patients need to demonstrate during a process of capacity determination: 1) evidencing a choice; 2) appreciation of the issue; 3) "rational manipulation" of information; 4) appreciation of the situation. Levenson (1990) describes behaviors that would be reasonable to expect at each level of this decisional capacity hierarchy. For example, at the first level, the patient should manifest consent or "cooperate" with the plan. At the second level, the patient would repeat the information in his/her own words and appear to be aware of the situation. At the third level, the patient would be expected to logically express how his or her opinion (i.e., values) related to the situation. Finally, at the fourth level, the patient should express some understanding of the consequences of his or her decision.
The process for deteiTrtining decisional incapacity recommended in the literature does not rely on mental status tests alone but rather on the observations and judgments of the family and the interdisciplinary health care team (Midwest Bioethics Center, 1996). Confidence in the accuracy of the determination is secured over time. Proof or verification of capacity lies in the stability and coherence of the person's decision. The process takes into account variations in capacity associated with time of day, interviewer, physical state and medication effect, language and expressive ability. An individual's idiosyncratic beliefs or values are not an indicator of incapacity.
Reasons to "sciutinize" capacity include patient ambivalence, vacillation, apathy, and /or clinical evidence of altered DMC during or preceding the disclosure of information. Specific behavioral examples would be when the patient:
* understands little or nothing about what has been explained;
* is unable to appreciate the significance or usefulness of the information in regard to his/her own situation;
* uses information in a highly idiosyncratic fashion;
* is unable to use the information in making a decision
* is unable to make any decision.
Applying the principle of decision specific capacity, the reason for the capacity determination should dictate the rigor of the observations, documentation and assessments. In some situations, one person alone can readily make a capacity determination; in other situations, such a determination is best made by the interdisciplinary team.
Informing the Patient
Prior to a capacity determination, the patient needs to receive adequate information about the decision to be made, and this information must be provided in a manner reasonably calculated to be understood (Haddad, 1988; Meisel, 1989). The accuracy of a capacity assessment will be affected by the amount of information that the patient has received and its method of disclosure. Relevant information should be supplied in a format and under conditions that are supportive. The provider may need to undertake repeated and lengthy communication sessions in communicating information; lack of "informational agility" is not a reliable test of mental incompetency. The fact that older people may need more time and repetition of information is not in itself evidence of incapacity (Collopy, 1994). Understanding of information is known to be affected by socioeconomic status, education, ethnicity and race (Applebaum & Grisso, 1988; Willis, 1996). If at all possible, the person making the capacity determination should be of similar ethnic or cultural background to the patient (Applebaum & Grisso, 1988). Moreover, attention should be given to the language used in disclosure (Fitten, Lusky, & Hamann, 1990).
Mental Status Assessment (MSA) Instruments
Valid and reliable mental status tests can be a useful starting point in assessing capacity (Folstein, Folstein, & McHugh, 1975; Morris et al., 1994; Pfeiffer, 1975). These instruments provide information as to a person's ability to attend and concentrate, use speech and language appropriately, remember certain kinds of information, perform visual and spatial activities, and access the higher cognitive functions involved in abstract reasoning, judgment and mathematical calculations (Walsh, Brown, Kaye, & Grigsby, 1994). Most MSA instruments do not assess mental phenomena, such as mood, perceptions, thought content or depression.
It is important to keep in mind that MSAs were not developed to measure the capacity to make an informed decision. Rather MSAs are diagnostic tools that suggest the presence, degree or absence of dementia and delirium. Responses (and thus scores) of the various MSAs are known to be influenced by a person's education, fatigue, depression, language skills and culture (Crum, Anthony, Bassett, & Folstein, 1993). Furthermore, the reliability of data obtained during mental status screening is influenced by the assessor's skills and consistency of test administration across assessors (Teresi & Holmes, in press).
Despite its usefulness, an MSA should not serve as the sole surrogate or "gold standard" for the determination of decisional capacity. Fitten and Waite (1990) found differences in elderly hospitalized patients' decisional capacity between their responses to clinical vignettes in comparison to their MMSE scores and to physician judgments of their decision-making capacity. When elderly nursing home residents used increasingly complex vignettes, only 33% had intact decision-making capacity whereas their primary physicians felt that 77% of the residents had decisional capacity (M. Brod, personal communication, November 1990).
Physician Determination of Capacity
If there is a "gold standard" in determination of decision-making capacity it is the evaluation by a physician. Yet reliance on expert medical opinion can result in inaccurate judgments about capacity. Findings of various studies call into question the widespread belief mat physicians in general, and psychiatrists in particular are experts at capacity (and competence) assessment. Markson and colleagues (1994) found that while most physicians knew the correct standard for capacity, most incorrectly assumed that clinical conditions such as dementia and psychosis establish incapacity. Even psychiatrists answer correctly only half of the time when asked if a patient with dementia could be competent (Markson, Kern, Annas, & Glantz, 1994).
Physicians generally assess capacity on the basis of bedside cognitive assessment (Gerety, Chiodo, Kanten, Tuley, & Cornell, 1993), or they rely on staff's general impressions and /or brief mental status examinations (Fitten, Lusky, & Hamann, 1990). Yet the elderly are particularly vulnerable to strangers, unfamiliar environments, and the sense that they are being "quizzed" (Collopy, 1994). Physicians seem less willing to properly apply a standard of capacity assessment when this would lead to an outcome that they find unacceptable or medically irrational. Hence, physicians have been shown to disagree with the right of capacitated patients to refuse treatment (Markson, Kern, Annas, & Glantz, 1994).
The President's Commission (1982) recommended that health care institutions develop clear policies as to who is responsible for assessing incapacity, and by what standards. Persons assessing capacity should know the kinds of inquiries to make, the data to collect, the records to keep and mechanisms for review of determination of incapacity. Rutman and Silberfeld (1992) found that an interdisciplinary panel is more likely to find a patient to have capacity than would be predicted by his or her score on a mental status test, such as the MMSE. They suggest that there is a difference between the "knowing and the doing" or the cognitive versus the functional or instrumental components of capacity determination. In this respect, it is not uncommon for people with excellent verbal and social skills to be inaccurately assessed as having greater decisional capacity than is actually the case when more carefully evaluated. The converse is also true. People with limited social and verbal skills may be incorrectly assessed as lacking capacity, especially if they have compromised functional abilities.
REMEDIAL CLINICAL CONDITIONS THAT IMPAQ ON DECISION-MAKING CAPACITY
Depression, dementia, anemia, metabolic conditions, medication abreaction, relocation stress and pain are among the clinical conditions that can affect decisional capacity. Studies of depression and decisionmaking, for example, note a relationship between clinical depression and the content of decision-making (i.e., scope, depth, reality, validity) (Howe, Gordon, & Valentin, 1991; Krynski, Tymchuk, & Ouslander, 1994; Schwartz, 1988), cognitive functioning (Lichtenberg, Ross, Mills, & Manning, 1995), and instability as to treatment choice (CohenMansfield, Groge, & Billig, 1992; Ouslander, Tymchuk, & Krynski, 1993). Lee and Ganzini (1994) found that medically ill depressed elderly patients preferred fewer life-sustaining therapies in their current health and when the prognosis was good than did a control group. While these studies do not show a conclusive relationship between depression and the refusal of life-sustaining therapies, taken together they consistently highlight differences in the treatment preferences of depressed and non-depressed patients.
If cognitive processes are altered by depression, then health care decisions are "inautonomous." In other words, the individual lacks capacity to make a decision. While Kafonek et al. (1989) reported that the Geriatric Depression Scale (GDS) was not sensitive for depression in a demented institutionalized elderly population, administering the GDS (or other instruments that measured depression) could be a procedural safeguard when cues and signs of depression are evident during the assessment of DMC in more cognitively intact, presumed capacitated individuals.
DOCUMENTATION OF DECISIONAL CAPACITY
Nurses' notes and the patient's (medical) record in general, have moved from documenting all care and observations, i.e., routine care, to documenting only what is not normal: "charting - and reporting - by exception." Yet documentation of a patient's statements and behavior could be a vital component of a capacity determination. Thought needs to be given, also, to where to include such documentation. Computer-generated care plans, flow sheets, clinical "pathways" and summaries of care generally address specific medical and surgical conditions or events. As such, there can be significant omissions regarding description of a patient's cognitive ability and decision-making.
Changes in nursing home regulations and the data-driven imperatives of the MDS system have led many nursing homes to eliminate the nursing monthly summary of care altogether. Even though the role of the interdisciplinary team in comprehensive assessment and care planning is strongly emphasized in regulation and standards of practice, the courts more often scan nurses' notes for information and clues about patient status (Fiesta, 1983). The MDS attempts to fill the gap by asking specific questions about the resident's mood, ability to follow directions, to make choices. Despite its inadequacies with regard to decisional capacity assessment, this structured information gathering exists in nursing homes only. Inasmuch as the issue of "standardized charting" remains unsettled, nurses should periodically document the patient's mental and cognitive state by describing their statements and actions. Nursing diagnosis could be useful in that it addresses the etiology and characteristics of an impairment or disability. Nurses' notes will not be helpful, however, in contributing to the evaluation of a patient's decision-specific capacity if the nurse lacks knowledge about the components of decisional capacity and competence (or the lack thereof).
It is strongly suggested that when a patient /resident is being assessed for decisional capacity, the interdisciplinary team convene to discuss what evidence is needed to determine whether the resident has the capability to make a particular decision. As stated earlier in this article, different kinds of decisions need different levels of decisional capacity; the decision is situation-specific. An individual may have the capacity for one kind or level of decision but not another. Nursing's role in assessment and determination of DMC is dependent on the structure of the nursing service. Different nursing delivery (or assignment) systems elicit different information about the patient. A primary care nurse assistant will know the patient differently than a nurse assistant in a task or functional delivery system. The head or charge nurse, usually the nursing professional who attends the team conference, will have a different knowledge of the patient than will the patient's "team leader." Those with the most knowledge of the patient should be asked to contribute relevant information about the person. In nursing homes, more often than not, this is the nursing assistant who cares for the patient.
The loss of personal power to make decisions that affect one's life is a profound existential loss. Nursing staff have more access to the patient than any other member of the health care team, even more than the family or significant other. The objectives of assessment are to cu^minish two types of errors: 1) mistakenly preventing persons who ought to be considered capacitated from directing the course of their treatment; and 2) failing to protect incapacitated persons from harmful effects of their decisions (President's Commission, 1982).
It is incumbent on nursing, on us, to use our information power in order to assure that the patients /residents retain their rights to make decisions that affect their well-being and care - as long as they are able. As nurses, we have a key role in this, but only if we understand what is meant by decision-making capacity.
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