Selection of appropriate tests and measures

After the patient history and interview and the review of systems, the next step in the patient/client management process is the selection of appropriate tests and measures that will identify the most important patient problems that require therapeutic intervention. In the clinical environment, the therapist often approaches this process by first identifying the functional activities that the patient is able and not able to do (activity limitation or functional limitation), hypothesizing the possible impairments causing this activity or functional limitation, and then testing the body systems and subsystems to identify the nature and extent of the impairments. Consistent with the International Classification of Functioning, Disability and Health (ICF) model, the client’s strengths are often emphasized as the foundation for this process. The approach is proactive and collaborative, truly capitalizing on the client’s potential and goals, and highlights the therapist-client partnership.

Tests of activity and functional performance

As mentioned previously, the therapist typically starts with the examination of functional activities. This step will allow the therapist to understand the specific functional tasks that the patient can do, as well as those activities or functions that the patient is unable to perform. It is important to observe the client during the performance of these tasks and to note the motor patterns used. Many functional assessment tools have been developed to provide a more objective assessment of everyday skills and tasks. Each tool is designed to measure and score a specific type of functional ability. Several tools test a range of skills from balance skills to walking ability during the performance of functional tasks. Some tests are quick and easy to set up and perform, such as the Functional Reach Test and Timed Up and Go (TUG) Test, whereas other tools may take longer to administer, such as the Berg Balance Scale or Fugl-Meyer Assessment. There are advantages and disadvantages to both of these types of tests. Those that are the quickest to administer tend to measure fewer functional skills and do not supply information on the total functioning of a client. However, if the clinician properly identifies the client’s problems and is able to focus on the most efficient way of measuring them, a quick functional test can be the most beneficial one to use. Tests that take a bit longer to administer typically assess multiple skills and supply the user with a more comprehensive picture of the client’s functional abilities including those in various domains such as gross mobility, self-care, cognitive ability, and communication ability, among others. Often the decision on the complexity of the assessment tool used is based on the client and family’s objectives and long-term goals.

Outcome scales for functional tests may be found in ordinal format (e.g., Functional Independence Measure [FIM], Barthel Index, Katz Index of Independence in Activities of Daily Living). Each has its own unique point value and range, varying from a two- to three-point scale (e.g., Tinetti Performance-Oriented Mobility Assessment [POMA]) to a seven-point scale (e.g., FIM). A few tools supply ratio scale data (e.g., the TUG, Functional Reach Test, and measures of gait velocity). Test data presented in ratio scale format will more clearly show incremental changes, thereby facilitating the comparison of pretherapy to posttherapy performance.

Tests of body functions and structures

After identifying problems with functional performance of activities, the clinician then focuses on the performance of appropriate tests for body functions and structures. Consistent with the ICF model, the intent is to identify which body systems or subsystems are intact and functioning normally and could be optimized as the patient works on regaining the ability to perform functional tasks or participate in life. In this step, it is also important to identify which body systems and subsystems are not normal. These body system impairments may be the cause of the functional loss.

Impairment (ICF; International Classification of Impairments, Disabilities, and Handicaps [ICIDH]; Nagi)¹¹ is defined as the loss or abnormality of physiological, psychological, or anatomical structure or function at the organ system level.¹² The clinician needs to make the distinction between primary impairments, which are a direct consequence of the client’s specific disease or pathological condition, and secondary impairments, which occur as sequelae to the disease or rehabilitation process or as the result of aging, disuse, repetitive strain, lifestyle, and so on. Moreover, the clinician must remember that, although functional limitations are usually caused by a combination of specific impairments, it is possible that impairments may not contribute to specific functional problems for a particular client. If this is the case, the clinician should make a determination regarding whether these impairments, if left uncorrected, will result in the development of activity limitations at a later time. Simultaneously, the patient needs to be a part of this discussion because the therapist may not have the time to address all impairments. The correction of particular impairments may have more meaning or value to the patient. To the consumer some impairments may lead to limitation of functions that are important to them, whereas other impairments may restrict an activity in which the patient would never want to participate.

The ultimate goal of any therapeutic intervention program is to attain the highest level of health and wellness possible. Measurement tools that the clinician chooses to use also need to reflect this end result. For example, “traditional” impairment measurements may indicate that a client demonstrates shoulder range of motion (ROM) that is decreased by 25 degrees. The more important question should be how this decrease in ROM affects the client’s ability to perform a functional task such as dressing or any other activity that the client perceives as important. The clinician is therefore encouraged to consider the functional implications of these measurements to obtain results that are more meaningful for the client.

The clinician is always faced with the challenge of identifying and administering examination tools that will not only reflect the client’s level of health and wellness but also reflect the client’s functional improvement as a result of the intervention provided. Functional measurement tools can be used as a baseline measure for those functional skills. However, these tools typically require a large improvement in a client’s functional performance for a clinically significant change to be seen. Results obtained from impairment tests can fill in the large gaps between numerical scores on functional scales, demonstrating objective measurements and trends in the direction toward improvement before any change is demonstrated on the functional examination.

Box 8-1 illustrates impairments that may be seen in patients/clients with movement disorders caused by neurological dysfunctions. These impairments are further classified as those that are within the central nervous system and those that are outside the central nervous system and result from interaction with the environment. These impairments are further discussed in detail in various sections of this book.

Range of motion testing is one example of a common neuromusculoskeletal system examination procedure. Clinicians depend heavily on ROM measurements as an essential component of their examination and consequent evaluation process. It is imperative that the data obtained from this procedure be reliable. It has been suggested that the main source of variation in the performance of this procedure is method and that reliability can be improved by standardizing the procedure.¹³

An impairment in ROM can be the result of other body system impairments. ROM measurements may be used to determine the effect of tone, balance, movement synergies, pain, and so forth on the neuromuscular system and ultimately on behavior. Most important, the clinician needs to remember that the ROM needed to perform a functional activity is more critical than “normal,” anatomical, biomechanical ROM values and must be considered when labeling and measuring impairments. For example, full ROM in the shoulder is seldom needed unless activities of daily living, work, or leisure activities require it, such as performing a tennis serve or reaching overhead to paint a ceiling. When needed for specific tasks, goniometric measurements of ROM are appropriate, but at other times a functional range measurement may be sufficient.

Muscle strength testing is another commonly used examination procedure. Clinicians use various methods of quantifying strength including “traditional” manual muscle testing (MMT) and the use of a dynamometer. As with ROM, strength should be correlated with the patient’s functional performance. Again, the clinician may find a client to have 3/5 strength in the shoulder flexor muscle groups or find grip strength to be 35 kg, but the more important question should be “What does this mean in terms of the client’s ability to perform activities of daily living, and/or can he use that power in a functional activity?” The clinician is also advised to make the distinction between muscle strength and muscular endurance as it relates to function. A client may have sufficient lower-extremity strength and power to get up from the seated position; however, this does not necessarily mean that the client has muscular endurance to perform the task repeatedly during the day as part of normal everyday activities.

The status of the cardiac, respiratory, and circulatory systems significantly affects a client’s functional performance (see Chapter 30). Blood pressure, heart rate, and respiration give the clinician signs of the patient’s medical stability and the ability to tolerate exercise. The clinician may also obtain the results of pulmonary function tests for ventilation, pulmonary mechanics, lung diffusion capacity, or blood gas analysis after determining that the client’s pulmonary system is a major factor affecting medical stability and functional progress. Various exercise tolerance tests also attempt to quantify functional work capacity and serve as a guide for the clinician performing cardiac and pulmonary rehabilitation.

A client who has difficulty performing activities of daily living and who has neurological impairments in the central motor, sensory, perceptual, or integrative systems needs to undergo examination procedures to establish the level of impairment of each involved system and to determine if and how that system is contributing to the deficit motor behaviors. Functional evaluation tools used may include the FIM, the Barthel Index, the Tinetti POMA, or the TUG test. The results of these tests will help to steer the clinician toward the most useful impairment tools to use to evaluate limitations in the various body systems. Impairment tools may include the Modified Ashworth Scale for spasticity, the Upright Motor Control Test for lower-extremity motor control, the Clinical Test of Sensory Interaction on Balance (CTSIB), or the Sensory Organization Test (SOT) for balance and sensory integrative problems, or computerized tests of limits of stability on the NeuroCom Balance Master, among others (see Appendices 8-A, 8-B, and 8-C).

The clinician is also advised to investigate the interaction of other organs and systems as they relate to the patient’s functional limitations. For example, electrolyte imbalance, hormonal disorders, or adverse drug reactions (see Chapter 36) may explain impairments and activity limitations noted in other interacting systems.

Tests for participation and self-efficacy

In ICF terminology, participation is defined as an individual’s involvement in a life situation. Domestic life, interpersonal interactions and relationships, and community, social, and civic life are some examples of aspects of participation that can be examined for each individual. Participation restriction is the term used to denote problems that individuals may experience in involvement in life situations. When considering participation it is important to obtain the individual’s perception of how the medical condition, impairments, and activity limitations affect his or her involvement in life and community. Therefore many of the tests for participation and self-efficacy are in self-report format. The Activities-specific Balance Confidence Scale (ABC), Short Form 36 (SF-36), and Dizziness Handicap Inventory (DHI) are examples of tests that can be used to gather information under this domain. These tests allow an individual to assess his or her health quality of life after an incident that affected activity and participation. Appendices 8-A, 8-B, and 8-D include tools that measure participation and quality of life.

Choosing the appropriate examination tool

The ability to choose the appropriate examination tool(s) for a particular client will depend on several factors:

The evaluator should select examination tools that will measure the client’s primary problems (activity limitations, impairments, and participation restrictions) and supply outcome values that are needed to set realistic treatment goals in accordance with those of the client and family and to plan efficient and effective intervention strategies. The clinician is advised to select functional tools that contain component skills that the particular client is having difficulty performing. Skills the client performs poorly will disclose the activity limitations. Skills the client performs well determine the client’s strengths and abilities. The evaluator must then focus on the client’s functional activity limitations as determined by the test(s) to determine the impairment tests that will be performed next. For example, if the client demonstrates difficulty in rising from a chair during a functional test and scores low on this skill on the outcome measure (the Tinetti POMA or Berg Balance Scale), the clinician must then closely examine the skill of coming to stand to determine the cause of the mobility limitation. The problem may be that the client cannot generate adequate muscle power to push up from the chair, does not have adequate ROM in the hip or the ankle joints to rise from the chair, or no longer sees a reason to get out of the chair, or that it hurts too much to even try. It may be a problem with dynamic balance during or after the transitional movement. Any impairment that is hypothesized by observing performance of the functional skill needs to be measured more specifically. It is up to the examiner to determine the next best steps to take to target the client’s problems as efficiently as possible, to measure and record the needed outcomes as objectively as possible, and then to set treatment goals in consultation with the client to design the best intervention to remediate or manage the problems.

Many of the examination tools that measure a client’s ability to perform functional activities have been accepted as valid, reliable, and useful for the justification of payment for services rendered. The number of activity limitations and the extent of the client’s participation limitation are often reasons why an individual either has accessed therapy services directly or was referred by a medical practitioner. For this reason, the third-party payer expects to receive reports concerning positive changes in the client’s functional status for therapeutic services to be justifiable (see Chapter 10). The initial list of functional or activity limitations or participation restrictions helps the therapist determine the extent of, expectations for, and direction of intervention, but it does not determine why those limitations exist. This is the question that is critical to answer as part of the evaluation process. Examination tests and procedures that identify specific system and subsystem impairments help the therapist determine causes for existing participation and activity limitations. These tools need to be objective, reliable, and sensitive enough to provide needed communication to third-party payers to explain the subsystem’s baseline progress during and after the intervention. These tools should also supply explanations for residual difficulties in the event that the functional problems themselves do not demonstrate significant objective change or show progress within the time frame estimated.

Using the evaluation process to link body system problems, activity limitations, and participation restrictions to intervention

After objective measures have been obtained for activity limitations, body system and subsystem impairments, and participation restrictions, clinicians must determine whether the impairments or the functional problems are changeable to a more independent, safe, and functional level. In certain situations a mobility limitation may be remediated and become more functional, although the contributing component impairments may remain unchanged. In other situations, impairment measures may significantly improve but the functional problem may remain unaltered. This is especially true when one impairment is significantly improved but functional progress is masked by the contribution of other impairments. The examiner must be able to come to a conclusion regarding the relationship between the client’s activity limitations and the existing body systems impairments. Without an understanding of this relationship, it is difficult to assess the effect of the treatment intervention(s) on an individual.

The interactions and interrelationships of the identified functional problems and impairments provide the clinician with an initial status or problem list specific to that individual. That list helps the clinician formulate a diagnosis for the movement dysfunction. Through consideration of the objective values obtained during the examination process, a target status to be reached at the conclusion of therapeutic intervention can be estimated. That target status is both impairment and function driven and traditionally would be considered a list of outcome goals. The interactions between impairments and their related activity and participation limitations make up the unique problem map of that individual and direct the clinician toward selecting optimal interventions.

The prognosis made by the clinician is based on the assessment of the likelihood that the patient will achieve the target outcome in a given time frame and estimated number of visits needed to reach the treatment goal. Once the clinician has measured and identified specific activity limitations and their respective impairments, he or she then has an excellent opportunity to conceptually understand how various impairments affect multiple functional problems and which impairments are activity specific.

The following case scenario synthesizes the clinical examination and evaluation process used by physical and occupational therapists.

Assume that a clinician has been called in to examine a client who has sustained an anoxic brain injury during heart surgery. The client’s cognitive ability is within normal limits, and he is highly motivated to get back to his normal activities. He is retired; he loves to walk in the park with his wife and to go on birdwatching experiences in the mountains with their group of friends. The clinician must select which functional tests to use to obtain an objective initial status and target the client’s problems. Currently the client requires assistance with all gross mobility skills and is demonstrating difficulty balancing in various postures and performing activities of daily living. Results of functional testing reveal that the client demonstrates significant limitations, requiring moderate assistance in the activities of coming to sit, sitting, coming to stand, standing, walking, dressing, and grooming. Assume that the client also displays impairment limitations in flexion ROM at the hip joints caused by both muscle and fascia tightness and hypertonicity within the extensor muscle groups. He has compensated to some degree and is able to perform bed mobility independently. Upper-extremity motor control is within normal limits, and thus the client is capable of performing many activities of daily living as long as his lower trunk and hips are placed in a supportive position and hip flexion beyond 90 degrees is not required. The client has general weakness from inactivity, and power production problems in his abdominals and hip flexor muscles owing to the dominance of extensor muscle tonicity. Once he is helped to stand, the extensor patterns of hip and knee extension, internal rotation, slight adduction, and plantarflexion are present. He can actively extend both legs after being placed in flexion, but he is limited in the production of specific fine and gross motor patterns. Thus a resulting balance impairment is present owing to the inability to adequately access appropriate balance strategies caused by the presence of tone, limb synergy production, and weakness in the antagonists to the trunk and hip extensors. Through the use of augmented intervention (see Chapter 9) the client is noted to possess intact postural and procedural balance programming; however, both functions are being masked by existing impairments. The decision is made to perform impairment measures, including assessments of ROM at the hip, knee, and ankle joints; the ability to produce strength in both the abdominal and hip flexor muscle groups; and volitional and nonvolitional synergic programming, balance, and posture, and volitional control over muscle tone. The demand on ROM, power production, and specific synergic programming will vary according to the requirements of the functional activities performed.

Using a clinical decision-making process, the clinician will conclude that the impairments that are being targeted to measure will vary from one functional activity to the next. For instance, if this client is demonstrating difficulty rising from a chair, the target impairment may be a ROM measurement. This same ROM impairment may also contribute to problems with moving about the base of support in functional sitting. The clinician makes the determination as to the extent to which the impairment interferes with each functional problem for that particular client.

These objective measurements help the clinician explain which outcomes would be expected to be achieved first and why. These measurements are recorded as part of intervention charting and help to objectively demonstrate that the client is improving toward functional independence. They also give an indication of what the client still needs to reach the desired outcome, the rate of learning that is taking place, and an estimation of recovery time that is still required. These objective measurements give to the clinician and the client a better avenue to discuss expectations with family members, other medical practitioners, and third-party payers. In this example, assume that, after intervention, functional ROM in the hip was achieved. However, this improvement did not result in an improvement in the activity problems because synergic programming prevented adequate hip flexion during one or more functional activities. Understanding and measuring the difference between lack of ROM as a result of muscle or fascia tightness versus lack of range from abnormal synergic patterning helps the clinician communicate why a client is successful in one activity and may still need assistance in another.

Scores obtained from tests of activity, participation, and impairments supply statistically important measurements that can then be used to discuss the limitations placed on the therapeutic environment by fiscal intermediaries. Therapists must be clear when documenting the initial status and the target status for clients so that the recommended intervention and length of stay may be justified (see Chapter 10).

When making a determination of the potential impact of an intervention on improving a client’s problems, clinicians must remember that a key factor in this process of examination and evaluation is the acceptance of the movement dysfunction or impairment by the client. A mobility problem or impairment may be clearly identified by a functional test or impairment test; however, the client may deny that the problem even exists. Acceptance of the problems by the client and a willingness to change are critical to the client’s adherence to the intervention strategy.

As mentioned earlier, the identification of potential impairments was done after functional testing to streamline the examination process. After performing the functional examination, the therapist postulated that the client might have impaired motor control, muscle weakness, sensory deficits, pain, and decreased endurance that may have been causing the functional limitations. MMT revealed lower-extremity strength of 1/5 in both ankle motions, 2/5 in both knees, and 3−/5 in both hips. Upper extremities tested as 1/5 finger flexors (incomplete grip), 2/5 wrist motions, and 3+/5 in both elbow motions. Shoulder and trunk strength were within functional limits for all motions. Sensory testing indicated absent touch and proprioceptive sensations from the foot to the knee of both lower extremities, with impaired sensation from the thighs to the hips. Both hands and wrists tested absent to touch and proprioception, with the elbows and shoulders testing intact. The client’s endurance was limited to short bouts of activity (3 to 5 minutes), with rapid muscular and cardiovascular fatigue. The presence of these impairments helped to explain the resultant functional limitations tested earlier.

In terms of standardized functional tests, the multidisciplinary FIM could give insight into this patient’s ability to function in multiple domains and categories. Baseline scores on the Tinetti POMA and the Berg Balance Scale could be collected because this client is expected to regain further function in balance and postural control as recovery from the condition occurs. As the client regains strength and peripheral sensory ability, he may be able to perform the TUG and the 10-Meter Walk Test. These functional assessments paint a better picture of what the client can and cannot do, as well as providing a way to measure functional progress in various activities throughout rehabilitation.

When determining an appropriate tool to examine a client’s functional status, the clinician must also consider the “ceiling and floor effect” of the functional tools. In this particular case, the patient is probably unable to perform the Functional Gait Assessment (FGA) but may be appropriate for beginning the balance portion of the Tinetti POMA. As the patient progresses, the predictive and discriminative properties of some of these tests could provide information regarding the patient’s likelihood of falling, or ability to safely perform selected functional tasks.

Special note: Condition-specific examination tools can be found in the respective chapters: