**Figure 1.**

*Essentials in Hip and Ankle*

cal outcome measures.

to measure dysfunction at this level. Furthermore, the International Classification of Functionality (ICF) proposed by the World Health Organization (WHO) suggests that health issues should be considered by taking into account individual function, activity, and social participation. The impact that injuries, illnesses, and any other harm might have upon health, especially over functionality and quality of life, must

Usually, ankle dysfunctions require the involvement of a wide variety of healthcare professionals in order to achieve excellence in recovery and functionality. This is particularly true when the treatment plan includes surgery, medications, rehabilitation program, and many other interventions carried out by different professionals. Multidisciplinary healthcare thus requires instruments that work across distinct

The health team may have priorities that can diverge from patient-specific needs

or beliefs. This may happen often because both look for a health condition from different backgrounds and starting points and this communication noise may lead

Focusing on the patient, who is most interested in full recovering of his/her health, quantifying subjective perception of functional status as well as healthrelated quality of life represents a challenge both for clinicians and researches, particularly in the field of rehabilitation. A patient-centered or also called clientbased assessment tool is needed and should meet the clinical needs of both the patient and the healthcare team, in such a way that it must be practical and accepted

Client-based assessment instruments, like questionnaires, are tools suitable to comprise the domains of activity and social participation being commonly the selected instrument for the assessment of health-related quality of life. They have the ultimate goal of transforming subjective measures into objective data that can be quantified and analyzed. Self-report questionnaires are useful both for clinical and scientific research purposes once they combine efficiency, reliability, and low cost and, at the same time, meeting the necessity to quantify patient-centered clini-

**3. Practical scenario: clinical use of self-report assessment tools**

hindfoot scale (AOFAS) are both examples of condition-specific measures.

Every clinical outcome measure may have five goals in order to be useful in a clinical-based scenario. The acronym that exemplifies this feature is known as

One way to classify questionnaires and functional scales is by their assessment application (see **Figure 2**). In this case, they can be categorized as being generic or specific. Generic questionnaires measure overall health, within biopsychosocial approach, and are intended to be applicable across a wide spectrum of diseases, interventions, demographic, and cultural subgroups. The most famous and used instrument that encompasses this properties is the 36-item short-form health survey (SF-36), which measure health-related quality of life in two main domains of mental and physical health. On the other hand, disease-specific measures aim to assess the most important traits usually affected by a condition of interest and that can be used to determine clinical improvement or deterioration. The foot and ankle outcome score (FAOS) and the American Orthopedic Foot and Ankle Society ankle-

be considered in a context of clinical evaluation in the health area.

disciplines in a sense of combining them and unifying perspectives.

to inappropriate treatment plan and can decrease patient's compliance.

by everyone involved in a treatment context [1–17].

SMART goals and can be visualized in **Figure 1**.

**3.1 Target population and purpose of the measurement tool**

**66**

*SMART goals for a clinical assessment tool.*

**Figure 2.** *Questionnaires and functional scale classification schema.*

Another form in which self-report tools can be organized is in relation to the clinical function (see **Figure 2**). Within this context, they can be discriminative or evaluative instruments. The selection of one type over the other depends on the desired use of the instrument. Discriminative instruments, such as the Cumberland ankle instability tool (CAIT), can be used to identify individuals with a particular disorder, in this case, chronic ankle instability. Evaluative instruments are developed to follow up and measure an individual's change, thus assessing the effectiveness and outcome of treatment. The foot and ankle ability measure (FAAM) and lower extremity functional scale (LEFS) are examples of evaluative instruments. Information acquired from an evaluative instrument is useful only if evidence is available to support the interpretation of scores obtained in the specific population in which the instrument is intended to be used.

#### **3.2 Practicality and feasibility**

The main factors when considering practicality are the following:


Although patients may appear to have time to complete self-report measures in the waiting room before being seen for therapy, lengthy or numerous self-report forms may interfere with patient care. Some people may fatigue while completing self-report forms, and this fatigue could influence their responses. When selecting a self-report instrument, clinicians should pay attention on the time needed to fulfill the questionnaire. Usually, the authors report this time in scientific publications or in user's manual, when applicable. For a self-administered questionnaire, ideally no more than 10 min should be needed to answer all items.

Another important point to consider is the form of test administration. Some self-report questionnaires, especially translated versions, may require a structured interview for a proper measurement reliability. Although this procedure is likely to increase the time needed to fill in the questionnaire, it is essential to achieve an acceptable level of accuracy in measurement. Instructions for taking a test are sometimes not sufficient, and special training and experience may be necessary. Usually, there is no need for special training, but test familiarization and reading the user's guide, when applicable and suggested by the test developers, may be helpful. A great advantage of self-report measures is that no equipment or specific setups, and no professional or support staff are needed to help with the tests.

A strong point for a clinician is the importance of immediate feedback and interpretation of test result. Consequently, a scoring method that can be done manually without any software or computer assistance is desirable. It is common practice for a test's score to be attained by just summing up the individual items score and then transforming this result into a percentage. It is important to know the correct interpretation of this value, whether 100% means full function or the worst score for functionality.

Some instruments result in a single composite score or in a composite score and subscale scores for components of the item being measured. A single composite score can be desirable for communicating findings to others and for identifying people who are at risk for chronic ankle instability, for example. A composite score can be useful for discriminative instruments once a single cutoff score is an important clinical information for a diagnosis process. However, a single composite score may not represent a comprehensive analysis about physical function or anklerelated functionality for a specific task or domain. Subscale scores for components of physical function, like activities of daily living or sport related tasks, may be more useful for planning intervention and monitoring outcomes.

### **4. Psychometric properties**

In order to ascertain that a questionnaire has proper methodological quality, information about its psychometric properties must be available. Ideally, although potentially time-consuming, information about the development of the

**69**

*Patient-Report Outcome Measures for Ankle-Related Functionality*

questionnaire can sometimes be useful for a better comprehension about target population and/or medical conditions. Some author's suggest eight criteria that should be taken into account when assessing the quality of such outcome measures. These include (1) conceptual and measurement model; (2) content and construct validity; (3) reliability; (4) responsiveness; (5) floor and ceiling effects; (6) internal consistency; (7) feasibility to answer, administer, and interpret; and (8) cultural and language adaptations (translations). Reference values for each of these variables have also been suggested aiming to help clinicians and researchers in the selection and use of the clinical assessment tool that bests suits their necessity.

For the purposes of this chapter, four basic variables will be addressed in detail. They contain the minimum information needed to select and use a self-report questionnaire. They are validity, reliability, internal consistency, and responsiveness.

Content validity examines the extent to which the concepts of interest are comprehensively represented by the items in the questionnaire. It is very important to know about the following aspects regarding the development of a questionnaire

• **Measurement aim of the questionnaire**: it can be discriminative, evaluative,

• **Target population**: it indicates whether the items were at the appropriate level of difficulty for the sample or the population for which the questionnaire was developed. If a questionnaire is intended to measure the functional status of patients with ankle/foot disorders, it is expected that items like *standing on tiptoes* should be much more relevant for such group than it would be for patients with knee problems. Nevertheless item's appropriateness, also the item's difficulty level, is another issue to be considered. Different populations demand different outcome measures. Ankle-related functionality of volleyball professional players, for example, requires items that measure function in a higher level of ability, with more challenging functional tasks, such as *jumping* and *landing*. In sum, a detailed description of the target population is crucial for judging the comprehensiveness and the applicability of the questionnaire for a given population.

• **Concepts:** for what the questionnaire was developed to measure. Clinicians must be aware about the relevant concepts that a questionnaire is able to measure. Quality of life, functionality, and symptoms are examples of different concepts a questionnaire may assess. These different outcome levels should clearly be distinguished and measured by separate subscales. Self-report instruments measures at the level of individual's capacity, that is, what he/she thinks they are able to do. Functional scales usually assess individual's perfor-

• **Item selection and item reduction:** a thorough list of potential items relating to symptoms, signs, and limitations can be gathered from literature review and input from expert clinicians (in the case of ankle-related functionality, from physicians, surgeons, and physical therapists) who treat individuals with foot and ankle-related disorders. Another important source of information is individuals with musculoskeletal pathologies within this scope. A common procedure is ask for all these people to rate each potential item from −2 (not important) to +2

(very important), and after that, reject all items with a score below +1.

or predictive. Different items may be valid for different aims.

*DOI: http://dx.doi.org/10.5772/intechopen.89509*

for an appropriate judgment of content validity:

mance, which is what he/she actually can do.

**4.1 Validity**

*Patient-Report Outcome Measures for Ankle-Related Functionality DOI: http://dx.doi.org/10.5772/intechopen.89509*

questionnaire can sometimes be useful for a better comprehension about target population and/or medical conditions. Some author's suggest eight criteria that should be taken into account when assessing the quality of such outcome measures. These include (1) conceptual and measurement model; (2) content and construct validity; (3) reliability; (4) responsiveness; (5) floor and ceiling effects; (6) internal consistency; (7) feasibility to answer, administer, and interpret; and (8) cultural and language adaptations (translations). Reference values for each of these variables have also been suggested aiming to help clinicians and researchers in the selection and use of the clinical assessment tool that bests suits their necessity.

For the purposes of this chapter, four basic variables will be addressed in detail. They contain the minimum information needed to select and use a self-report questionnaire. They are validity, reliability, internal consistency, and responsiveness.
