Cerebral Palsy Outcome Measures

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Original Editor - Kim Jackson as part ICRC Cerebral Palsy Content Development Project.

Top Contributors - Naomi O'Reilly, Kim Jackson, WikiSysop, Rucha Gadgil, 127.0.0.1, Jess Bell and Olajumoke Ogunleye  

Introduction

Cerebral palsy (CP) is a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing foetal or infant brain (Rosenbaum et al., 2007). Rehabilitation in cerebral palsy focuses on promoting mobility, functional independence, and quality of life through various therapeutic strategies. In order to be able to provide quantifiable data on functional changes over time, it is important to use outcome measures, to track progress, modify interventions, and demonstrate the impact of therapy to patients, families, and healthcare systems.

Outcome Measures

An Outcome Measure is the result of a test that is used to objectively determine the baseline function of a patient at the beginning of treatment. Once treatment has commenced, the same instrument can be used to determine progress and treatment efficacy. With the move towards Evidence Based Practice (EBP) in the health sciences, objective measures of outcome are important to provide credible and reliable justification for treatment. The instrument should also be convenient to apply for the therapist and comfortable for the patient. An integral part of evaluating clinical practice is to objectively assess the intervention and measure it against a set of outcomes to determine its efficacy. Prior to determining any orthotic intervention, the careful choice of treatment goals and aims is essential in children with complex neuromuscular disability in order to identify and determine appropriate outcome measures. 

Outcome measures can assess various dimensions, including motor skills, functional independence, quality of life, participation in daily activities, and specific impairments like spasticity or dysarthria. Outcome measures:

• Enhance Treatment Planning and Decision-Making: Outcome measures contribute to individualised treatment planning by providing valuable insights into a patient's functional abilities and limitations. The Gross Motor Function Classification System (GMFCS) is widely used in CP rehabilitation and helps clinicians establish baseline assessments, set realistic goals, and monitor progress over time . Such data-driven approaches empower clinicians to make informed treatment decisions and optimise outcomes.

• Facilitate Interprofessional Collaboration: CP rehabilitation often involves a multidisciplinary team. Standardised outcome measures act as a common language, facilitating communication and collaboration among healthcare professionals. For instance, the Manual Ability Classification System (MACS) evaluates upper limb function and assists clinicians from various disciplines in sharing and interpreting assessment results. This collaborative approach supports a comprehensive and coordinated care plan.

• Monitor Progress and Evaluate Treatment Efficacy: Regular assessment of functional abilities is crucial for monitoring progress and evaluating the effectiveness of interventions. The Paediatric Evaluation of Disability Inventory (PEDI) assesses functional capabilities in self-care, mobility, and social function domains. By utilising such measures, clinicians can track changes in performance, identify the impact of interventions, and optimise outcomes for individuals with CP.

Clinician Reported Outcome Measures

Clinician-reported outcome measures (ClinROs) are an essential component of assessing and managing cerebral palsy (CP). They provide an objective and standardised method for clinicians to evaluate the impact of interventions and track progress over time. Examples include the Timed Up and Go test (TUG), the 88 and 66 item Gross Motor Function Measure (GMFM-88 and GMFM-66 respectively), Gross Motor Performance Measure (GMPM), Clinical Gait Assessment Score (CGAS), Pediatric Balance Scale (PBS) and the Standardised Walking Obstacle Course (SWOC). These outcome measures have been proven to be valid and reliable to evaluate motor function and performance in children and the choice should be based on the specific context and objectives of the assessment.      

Patient Reported Outcome Measures

A Patient Reported Outcome Measure (PROM) such as the Paediatric Outcomes Data Collection Instrument (PODCI), the Pediatric Evaluation of Disability Inventory (PEDI) or Gillette Functional Assessment Questionnaire (FAQ), permits the child and family to provide information from their own everyday environment that relates not only to the function of the child’s gait but also to quality of life issues. It is not always possible for healthcare professionals to observe children in their own environment, which makes the PROM a powerful and valuable evaluation tool.

The PODCI is a parent-reported outcome measure that assesses the mobility, physical function, comfort, happiness and expectations of the healthcare interventions in children with musculoskeletal health issues.  In accordance with the ICF values, it not only focuses on assessing function and performance following healthcare interventions, but also evaluates quality of life issues. The PODCI has good reliability and validity when evaluating quality of life issues and walking function in children with Cerebral PalsyP, but does have floor and ceiling effects in the transfer and mobility scales.   It demonstrates only a modest sensitivity to detect changes of walking function in children with CP following orthopaedic surgery as the scoring system is considered too expansive to detect subtle changes.   Lee et al.  found statistically significant improvements in PODCI scores following orthopaedic surgery, but only minimal clinically relevant results. This may mean the PODCI may not be sensitive enough to evaluate the effects of orthotic intervention on mobility and provide results that are clinically relevant.

The International Classficiation of Function, Disability and Health

The International Classification of Function, Disability and Health (ICF) is the World Health Organization's framework for measuring health and disability at both individual and population levels. The ICF has shifted the focus of the impairments in children with Cerebral Palsy from restriction in joint ROM or abnormal muscle tone to the evaluation of functions by assessing the quantitative and qualitative aspects of a child’s Activities of Daily Living (ADL). It states that the focus of rehabilitation should be shifted from identifying a person’s disability to focusing on enhancing a person’s function, ability and performance quality for each individual in a contextual manner. The ICF identified domains that should be evaluated in children with Cerebral Palsy to include body function and structure, activity and participation. A consensus-based survey of clinicians, parents and youth with Cerebral Palsy supported these domains as relevant to the evaluation of all health care interventions in children with Cerebral Palsy.

The primary goal of orthotic treatment of ambulant children with CP (GMFCS I-III) is to optimise their gait. This is with the expectation that it will preserve or improve their physical function and provide them with the ability to increase their participation in physical activities, recreation and sport.  Evaluating orthotic intervention requires the use of outcome measures that will not only assess the function and quality of walking, but also the health related quality of life. Quality of life is frequently used as a ‘catch all’ expression for any self-reported measure, even when the instrument is capturing information objectively verifiable as functional ability, activities or participation.

Given the heterogeneous nature of the Cerebral Palsy population, the goals of rehabilitation are often widely distributed across the ICF domains. This may result in problems interpreting the outcome when using standardised outcome measures alone.   Items in a standardised outcome measure may not match the individual treatment goals and even if they do, the outcome may not necessarily represent goal attainment.

Outcome Measures for Children with Cerebral Palsy

When choosing outcome measures it is important to focus on the expectations for children with CP of the same age and gross motor function, rather than those for children without developmental delays.Although some of these measures can be used independently many should be used in conjunction with other tools to ensure that all needs are met.

Bayley Scales of Infant and Toddler Development

The Bayley Scales of Infant and Toddler Development (Bayley-III) is a widely used assessment tool designed to evaluate the developmental functioning of infants and young children. It plays a significant role in assessing children with cerebral palsy and provides valuable insights into their cognitive, language, motor, and socio-emotional development.

The Bayley-III is relevant for children with CP to assess developmental delays and identify specific areas of impairment. It can assist in treatment planning and intervention strategies by identifying areas of strength and weakness. The assessment results can guide clinicians in setting realistic goals and monitoring progress over time.

One notable feature of the Bayley-III is its ability to assess different domains of development. The cognitive scale assesses problem-solving, memory, and early academic skills. The language scale evaluates expressive and receptive language abilities. The motor scale examines fine and gross motor skills, including reaching, grasping, sitting, and walking. Finally, the socio-emotional scale explores social interactions, emotional regulation, and behaviour.

Gross Motor Function Measure

The Gross Motor Function Measure (GMFM) is a widely employed assessment tool that provides both objective and quantitative data on motor function. It is used to evaluate the gross motor abilities and functional limitations of children with cerebral palsy (CP). It assists in establishing a baseline assessment, setting functional goals, and monitoring progress over time. The measure is sensitive to changes in motor skills and can be used to track improvements resulting from therapy interventions or surgical interventions.

There are two versions of the GMFM commonly used: GMFM-66 and GMFM-88. Both versions consist of a series of standardized motor skills tasks that assess a child's ability to perform various gross motor activities. These activities range from lying and rolling to walking, running, and jumping, depending on the child's age and functional level.

• The GMFM-66 is the original version of the measure and assesses 66 motor skills across five dimensions: lying and rolling, sitting, crawling and kneeling, standing, and walking, running, and jumping. Each skill is scored on a four-point scale, ranging from 0 (does not initiate) to 3 (performs fully).
• The GMFM-88 is an expanded version of the GMFM-66 and includes an additional 22 motor skills tasks, resulting in a total of 88 items. This version provides a more comprehensive assessment of gross motor function and allows for a finer-grained analysis of a child's abilities across a broader range of motor skills.
  

Paediatric Evaluation of Disability Inventory (PEDI)

The PEDI is a comprehensive tool for evaluating function in children with disabilities. It assesses three domains: self-care, mobility, and social function.These domains encompass a wide range of activities and skills that are essential for a child's independence and participation in daily activities. The self-care domain includes tasks such as dressing, eating, and personal hygiene. The mobility domain focuses on activities related to mobility, such as walking, climbing stairs, and using transportation. The social function domain evaluates a child's interactions with others, play skills, and participation in social activities.

The PEDI uses both interview and observational methods to gather information from multiple sources, including parents, caregivers, and healthcare professionals. This comprehensive approach ensures a holistic understanding of a child's functional abilities and limitations across different settings and situations.​

One of the key strengths of the PEDI is its ability to provide standardised scores, allowing for comparisons with typically developing children of the same age. The scores obtained from the PEDI provide valuable information for treatment planning, monitoring progress, and measuring functional outcomes in children with CP.

Gillette Functional Ability Questionnaire (FAQ)

The Gillette Functional Assessment Questionnaire (FAQ) is a widely used assessment tool designed to evaluate the functional abilities and limitations of children with CP, providing valuable insights of functional performance and participation in daily activities. The questionnaire covers a wide range of activities that are relevant to a child's daily life, such as dressing, bathing, eating, walking, and interacting with others. It allows parents, caregivers, and healthcare professionals to provide information about the child's functional performance and challenges they may face in different contexts.

One of the strengths of the FAQ is that no training or equipment is necessary to administer the 10-level, parent-reported questionnaire. The results from the FAQ can guide treatment planning and intervention strategies. By identifying areas of functional difficulty, healthcare professionals can tailor interventions to address specific challenges and optimise a child's functional performance. It also helps in setting realistic goals and monitoring progress throughout the intervention process.

Goal Attainment Scaling (GAS)

Goal Attainment Scaling (GAS): GAS is a method of scoring the extent to which patients' individual goals are achieved in the course of intervention. In cerebral palsy, it can be used to assess the effectiveness of interventions like botulinum toxin A injections, selective dorsal rhizotomy, and intrathecal baclofen therapy.During the intervention period, progress toward each goal is monitored and rated using the predefined scaling system. This rating is based on objective and subjective criteria related to the specific goal. The ratings can be performed by the healthcare professional, the child, and/or their family, ensuring a collaborative and holistic approach to goal assessment.

GAS involves a structured process that starts with the identification of meaningful and functional goals based on the child's unique needs and abilities. These goals can encompass various domains, such as mobility, self-care, communication, and participation in daily activities. The goals should be specific, measurable, achievable, relevant, and time-bound (SMART).

One of the key strengths of GAS is its ability to capture individualised changes in functional abilities, even when traditional assessment tools may not be sensitive to subtle improvements. By focusing on personalised goals, GAS allows for the evaluation of meaningful progress that is specific to the child's unique circumstances and needs. 

Cerebral Palsy Quality of Life Questionnaire (CP QOL)

The Cerebral Palsy Quality of Life Questionnaire (CPQOL) is a widely used assessment tool designed to evaluate the quality of life of children with cerebral palsy. It provides valuable insights into the child's physical, psychological, and social well-being, helping healthcare professionals understand the impact of CP on their overall quality of life. It includes child self-report and primary caregiver proxy report forms.

The CPQOL is specifically tailored to the unique challenges and experiences faced by children with cerebral palsy. It encompasses a range of domains that are important for assessing quality of life, such as physical well-being, emotional well-being, social well-being, and participation in everyday activities.

The questionnaire consists of a series of questions or items that are rated by the child, parents, or caregivers. It captures various aspects of the child's life, including their physical abilities, pain and discomfort, emotional state, social relationships, and participation in activities at home, school, and within the community.

The CPQOL offers a standardised and reliable approach to assessing quality of life in children with cerebral palsy. It allows for the comparison of individual scores with normative data, enabling healthcare professionals to identify areas of strength and areas where additional support may be needed.

The assessment results from the CPQOL can guide treatment planning, intervention strategies, and support services. By identifying specific areas of concern or reduced quality of life, healthcare professionals can develop targeted interventions to address those challenges and improve the child's overall well-being.

It is important to note that the CPQOL should be used in conjunction with other assessments, clinical observations, and professional judgment to gain a comprehensive understanding of a child's quality of life.

Peabody Developmental Motor Scales-2 (PDMS-2)

The Peabody Developmental Motor Scales (PDMS) is a widely used assessment tool designed to evaluate the motor development and motor skills of children, including those with cerebral palsy (CP). It provides valuable insights into a child's gross and fine motor abilities, helping healthcare professionals understand their motor functioning and identify areas of strength and challenge.

The PDMS assesses two primary domains: gross motor skills and fine motor skills. The gross motor skills domain focuses on activities that involve large muscle groups and overall coordination, such as crawling, walking, jumping, and balance. The fine motor skills domain evaluates more precise and intricate movements, including hand-eye coordination, grasping, and manipulation of objects.

The PDMS uses a combination of standardised tasks and observations to assess a child's motor skills. The assessment tasks vary depending on the age of the child being evaluated, ensuring that the assessment is developmentally appropriate and comprehensive. In addition to its diagnostic and assessment purposes, the PDMS can also assist in treatment planning. By identifying specific motor challenges, healthcare professionals can develop targeted interventions and therapy approaches to address those challenges and promote motor development.

Pediatric Outcomes Data Collection Instrument (PODCI)

s a parent-report outcome measure specifically designed to assess the functional health status and quality of life of children with various musculoskeletal conditions, including cerebral palsy (CP). The PODCI provides valuable insights into a child's physical function, pain, and overall well-being as reported by their parents or caregivers.  

The PODCI consists of several sub-scales that assess different aspects of a child's health-related quality of life, including upper extremity function, mobility, pain/comfort, and happiness. Each sub-scale includes a series of questions that capture the parent's perceptions of their child's functional abilities, limitations, and overall well-being. The sensitivity of the PODCI in evaluating post-surgery and and the effects of orthotic intervention can vary depending on the specific context and individual circumstances.   

Timed Up and Go (TUG)

The Timed Up and Go (TUG) test is a commonly used outcome measure to assess functional mobility and balance in various populations, including children with cerebral palsy (CP). The TUG test evaluates the time it takes for a child to stand up from a seated position, walk a short distance, turn around, and return to a seated position. The TUG test provides valuable information on a child's functional mobility, dynamic balance, and agility. It assesses their ability to perform daily activities that involve transitions, walking, and turning, which are essential for independence and participation in various environments.

In the TUG test, a child begins in a seated position on a chair or other designated surface. They are instructed to stand up, walk a specific distance (usually three meters or ten feet), turn around, and return to the seated position. The time taken to complete the task is recorded.

For children with cerebral palsy, the TUG test can be used to evaluate changes in functional mobility and balance following interventions, therapies, or treatments. By comparing pre- and post-intervention

Importance of Evaluating Outcome Measures

Evaluating the reliability, validity, specificity, and responsiveness of outcome measures related to cerebral palsy (CP) is of paramount importance in ensuring accurate and meaningful assessment outcomes. These considerations are essential for determining the usefulness and applicability of outcome measures in CP rehabilitation.

• Reliability: Reliability ensures consistent results when an outcome measure is administered multiple times under similar conditions. High reliability minimises measurement error and accurately reflects an individual's true abilities.
• Validity: Validity ensures that an outcome measure accurately captures the targeted constructs or domains of interest. Establishing validity requires evidence-based validation studies that evaluate the measure's ability to assess what it intends to measure .
• Specificity: Specificity refers to an outcome measure's ability to detect changes in specific aspects of CP. Measures with high specificity focus on relevant domains or functions, allowing for the identification of even subtle improvements or deteriorations.
• Responsiveness: Responsiveness indicates an outcome measure's ability to detect meaningful changes over time. A responsive measure should be sensitive enough to detect even small changes in functional abilities, accurately reflecting progress or decline.

By thoroughly evaluating reliability, validity, specificity, and responsiveness in outcome measures, healthcare professionals can confidently select appropriate measures that capture the complexities of CP and reliably track progress.