Investigation of Difference Between the Three Representatives of the Functional Status According to Executive Functions and Participation in Children With Hemiplegic Cerebral Palsy

Aim: This study aimed to explore whether the three functional status representatives differentiate according to actual performance in everyday life. Method: High to moderate functional motor and communication performance levels as described by Manual Ability Classication System (MACS), Gross Motor Function Classication System, and Communication Function Classication System (CFCS) were investigated in the context of the scaled scores of executive function tasks and participation in different life situations on ABILHAND-Kids and Child and Adolescent Scale of Participation (CASP) questionnaires. The data were collected from 98 children with hemiplegic cerebral palsy (CP) mainstreamed in regular schools (mean age 9,3 years [SD 3.0 years], [%95 CI:8.7-9.9]; 42 females, 56 males); 28,6% classied to level I, 29,6 % to level II, and 41,8 % to level III in MACS. Results: The study ndings demonstrated that scaled scores of the executive function tasks and participation in different life situations increased with the greater MACS, GMFCS, and CFCS levels (p<0,5). Conclusion: Data from both MACS, GMFCS and CFCS might be useful to predict a child’s actual performance in daily life.


Introduction
Assessment of the children with cerebral palsy (CP) has clinical importance in identifying the existing problems associated with the CP. Moreover, in either research or clinical settings, it is also bene cial to quick yet robust document the clinical characteristics of the disabled children [1]. Following that, classi cation systems were developed as practical tools to concisely provide knowledge to researchers or clinicians as a snapshot of a condition [2]. Consequently, classi cation systems might help both health professionals improve their communications with families/caregivers in clinical environments, and researchers constitute homogenous groups in research settings [3].

The Manual Ability Classi cation System (MACS), Gross Motor Function Classi cation System (GMFCS)
and Communication Function Classi cation System (CFCS) are the most prevalent functional classi cation systems to report the functional motor and communication skills of children with CP into ve-level, where level I represents the best and level V represents the worst performance in daily life [4; 5]. The Manual Ability Classi cation System was established to classify hand functions of children with CP based on the perceived hand use in daily living or structured settings [4; 6]. Although the MACS is commonly used to specify functional hand use both in clinical and in research settings [4; 7], there is still uncertainty related to the role of the affected hand when manipulating an object, e.g., uncertainty in the extent of involvement of the affected side while executing a meaningful activity. The Gross Motor Function Classi cation System was designed to discriminate the disabled children concerning gross motor functions [8]. Hence, using GMFCS and MACS together provides a broad range of information about functional motor pro le, including gross and ne motor function, at a particular time point in children with these three functional classi cation systems.
One aspect of the validation of the classi cation systems is their correspondence to the external references by using outcome measures [6]. Therefore, it is crucial to explore what means each of the classi cation system levels in the context of real-life utilizing the most appropriate outcome measures. In other words, validating the classi cation systems within the functional performance in daily life and understanding each level's potential difference in terms of an external reference is essential for clinicians, health professionals and caregivers/families. Following that, some studies have investigated a potential interrelationship between these three prevailing functional classi cation systems in perspective of executive function tasks, demonstrating a meaningful correlation among classi cation systems in question and functional performance in daily living [3; 6; 14]. However, while their unique resultants, these studies included participants of different typologies of CP at all MACS and GMFCS levels, which strengthens better understanding of the differences or similarities between high to moderate levels (I-III) of classi cation systems. Furthermore, it would be crucial to differentiate between high to moderate levels of classi cation systems in the context of executive function and participation to enhance communication between families and health professionals in the clinic settings and as well as to construct homogenous groups in the research settings. An actual discrimination between classi cation systems' levels based on the actual performance in basic daily living activities and involvement in different life situation is required to practically delineate the functional status of disabled children.
Based upon the premises mentioned above, the purpose of this study was to further investigate (1) actual differences between high to moderate levels of the prevailing functional classi cation systems in respect of executional functional tasks and participation in different life situations and (2) an inter-relationship between MACS, GMFCS, and CFCS. We hypothesized that there would be a potential difference between the high to moderate levels of the classi cation systems based on functional performance in real world.

Participant
Participants in this cross-sectional study were the children with hemiplegic CP between the ages of 7-14 years and were at the MACS, CFCS, and GMFCS levels I-III. Human Research Ethics Committee at the XXXX University approved the study protocols numbered 79236777-050.01.04. A convenience sample size of the 98 children diagnosed with congenital hemiplegia (56 males, 46 females) born in XXXX city was set from different rehabilitation centers. Informed consent was obtained and signed by the parents/guardian of the children. Participants' functional motor and communication levels were evaluated by an experienced rehabilitation therapist who is expert in this eld. Children with lower levels (IV-V) of functional motor and communication skills or diagnosed with acquired brain injury were excluded from the study.

Classi cation Tools of Functional Motor and Communications Performance
The participants' functional status in the study was documented using the GMFCS (interclass correlation coe cient [ICC]= 0,75) [15], MACS (ICC=0,7 to 0, 9)[6], and CFCS (ICC= 0.71 to 0.89) [9] based on both clinical observation and the reporting of child's physiotherapist or families. These three instruments are universally accepted to describe the functional performance as a snapshot of functional motor and communication skills [1; 11] on a ve-level scale from the score I to score V (lower level indicates the best capacity). Although some studies have attempted to explore the possible correlation between these instruments [9; 10; 14], the distinction among the classi cation systems' levels, especially between high levels based on the activity and participation in natural settings, remains to be determined.

2.4.Outcome Measures of Executive Function and Participation
The ABILHAND-Kids (test retest reliability ICC=0,92) [16; 17] was developed as a Rasch-based measure to report perceived manual ability of children with CP aged 6 to 15 years by their caregiver/parents [18]. The ABILHAND-Kids questionnaire consists of 21 items that are the best representative of speci c daily activities requiring one or both hand use [16]. The potential advantage of this questionnaire is its usefulness in clinical and research settings, as it can be quickly completed [18]. The total score can be calculated based on converting the raw score into a logit measure on the website of http://rssandbox.iescagilly.be [19] . Finally, ABILHAND-Kids has been validated in evaluating executive functions from the perspective of the manual ability of children with hemiplegic CP in clinical settings [16].
The Child and Adolescent Scale of Participation (CASP) (ICC=0.94) [20] was used to documenting the extent of child's involvement in different life situations, including participation in home, school, and community activities [21]. The CASP includes 20 ordinal-scaled items as to home participation (6 items), 2) community participation (4 items), 3) school participation (5 items), and 4) home and community living activities (5 items). Its assessment items are suitable for school-aged children (5 years or older) and coincide with many activities in different life situations. Psychometric properties of the CASP, such as internal consistency and test-retest reliability, were demonstrated to good [22] .

Statistical Analysis
Statistical analyses were performed using the SPSS software version 24. The variables were investigated using visual (histogram, probability plots) and analytical methods (Kolmogorov-Smirnov) to determine whether or not they are normally distributed. While investigating the associations between non-normally distributed and/or ordinal variables, the correlation coe cients and their signi cance were calculated using Spearman Test. Inter-relationship among MACS, GMFCS and CFCS was interpreted according to Spearman's correlation coe cient strength: r<0.2 very weak relationship; 0.2-0.4 weak relationship; 0.4-0.6 moderate relationship; 0.6-0.8 strong relationship; r>0.8 very strong relationship [23]. Categorical data were presented with percentage or frequency as appropriate, while continuous data were given as mean ± standard deviation. One-way ANOVA and Tukey's Test were performed to explore possible differences in mean executive functions and participation in different life situations scaled scores in three representatives of functional status on MACS, GMFCS, and CFCS. Standard error bars were used to demonstrate mean scores with %95 con dence interval (CI) on assessment tools by each classi cation system level. An overall p-value of less than 0.05 was considered to show a statistically signi cant result.

Results
All study participants' demographic characteristics and prognostic variables, and mean ages of participants classi ed into different GMFCS, MACS, and CFCS levels were shown in Table I. Children at each of the three levels of the classi cation systems demonstrated similarity in the age (p>0,05). Among the 98 enrolled children, 57 (% 58,2) were in good functioning levels in MACS (level I-II), whereas 41 (% 41,8) were in moderate functioning level (MACS level III). On average, % 55,1 could walk independently in all environments (GMFCS I), % 38.1 could walk with some limitations (GMFCS II), and only % 6.1 required a hand-held device for mobility. Considering that the MACS is a classi cation system of disabled children's hand function in ve levels (a lower value describes higher manual ability), most of the children in this study had effective hand use (MACS I-II). For communication skills, the predominant levels were level I (% 56.1) and level II (% 29.6) respectively, while fewer participants had a moderate score (level III; %14.3). That is, most of the study participants could independently and effectively communicate with people in most environments. Finally, except for hearing impairment, vision, speech, and cognition impairment was reported in 9 (% 9.2), 11 (%11,2), and 12 (% 12,2) of study participants, respectively. The distribution of children at different MACS levels within GMFCS levels was demonstrated in Table II. As outlined, most children in MACS level I (89,3%) were quali ed with GMFCS I; on the other hand, a very few percent (10,7%; 3 children) presented GMFCS II. Among children in MACS II, 55,2% was at GMFCS I; likewise, 44,8% was at GMFCS II. Finally, more than half children in GMFCS III (53,7%) featured level III of GMFCS. Table III  Children in level I, II, and III at GMFCS differed greatly for executive function tasks and participation in different life situations outcomes (p=0,000) (Table IV). Furthermore, results of pairwise post-hoc tests suggested that participants in a higher functioning GMFCS level had more signi cant outcomes in both executive function tasks and participation in different life situations than participants with a moderate functioning level (Post-Hoc: a>b>c). That is, the higher GMFCS levels were found to be associated with greater mean scores on both the ABILHAND-kids and CASP questionnaires. Children in GMFCS I presented greater variability for executive function tasks (ABILHAND-Kids) than those in GMFCS II and III. In contrast, children in GMFCS III demonstrated greater variability in scaled scores on CASP-Community Participation subdomains than those in GMFCS I and II (Figure 2 and 5) Table V shows executive function tasks and participation in different life situation outcomes by communication skills on CFCS instrument. Results of one-way ANOVA displayed statistical meaningful differences among three levels related to both manual ability and participation in different life situation outcomes (p=0,000). However, isolated comparisons (pairwise post-hoc tests with Tukey) revealed a statistically signi cant difference only between high and moderate levels (CFCS I-III), whereas it was not found out statistically meaningful differences between level I and II, and between level II and III (Post-Hoc: a>c, a=b, b=c). In other words, only children at level I and level III in CFCS exhibited variability in executive function tasks, and participation scaled scores on ABILHAND-Kids and CASP questionnaires. In contrast, a signi cant difference could not be found between children classi ed into CFCS levels closer to each other for actual performance in daily life. Furthermore, as demonstrated in Figure 3 and 6, children quali ed with CFCS III displayed greater variability in scaled scores on both executive function tasks and participation in different life situations than those in CFCS I and II.

Discussion
This current study demonstrated signi cant differences among each of three levels of functional motor skills, as measured by the MACS and GMFCS, for executive function tasks and participation in different life situations, as measured by ABILHAND-kids and CASP-subdomains in children with hemiplegic CP. Conversely, for CFCS levels, a statistically meaningful difference was found only between high and moderate levels as to actual performance in daily life. In contrast, no signi cant difference was introduced between levels closer to each other. In other words, executive function tasks and participation in different life situations increased with greater functional motor and communication levels. Furthermore, this study has demonstrated weak to moderate inter-relationships among high to moderate functional ability representatives, as measured by the rst three levels of MACS, GMFCS, and CFCS. Finally, our study demonstrated that most children with hemiplegic CP presented high functional skills on MACS, GMFCS, and CFCS (level I-II).
The gross motor function classi cation system, manual ability classi cation system, and communication function classi cation system objectively describe cerebral palsied children and adolescents' functional pro le through ve levels to ensure a practical communication between health professionals and families [10; 24]. In brief, the GMFCS delineates motor disability or current motor function [25]; the MACS describes the manual ability of children with CP to manage daily activities;[26] and the CFCS measures communication performance regardless of the underlying functional or structural impairment [9], i.e., each level of these classi cation systems is expected to characterize disabled children capacity concerning functional motor and communication skills with the most appropriate level [11; 24]. Although some studies have reported a strong relationship among this classi cation systems [10; 13; 24], the difference between each functional classi cation system level was explored only by Öhrvall et al.'s study [3], indicating a strong correlation among functional motor levels (MACS,GMFCS) and self-care and mobility capability.
Similarly, our study showed signi cant differences between three representatives of functional status for executive function tasks and participation in different life situations. Together with, our study is different from the Öhrvall et al.'s study for some aspects, by investigating a possible difference among three representatives of functional status as to executive function tasks (ability to manage daily activities) and participation in the different life situations. Then, our study was conducted on a more homogeneous group

Conclusion
In conclusion, this study is novel in investigating possible differences among three representatives of functional status associated with executive function tasks and participation in different life situations by using ABILHAND-Kids and the CASP questionnaires as an external reference. As we hypothesized, our study ndings revealed signi cant differences among each of the three levels of MACS and GMFCS for manual performance and involvement in different life situations. However, for the communication performance instrument, although it was demonstrated a signi cant difference between high and moderate levels (I-III), levels closer to each other (I-II or II-III) have not differed in actual performance in daily life. In conclusion, we assert that executive function tasks (manual performance in daily life) and participation in different life situations are more sensitive to levels of functional motor classi cation instruments than levels of communication performance instrument. In other words, our study's ndings indicated that executive function tasks and participation scaled scores increase with greater GMFCS, MACS, and CFCS levels, except for CFCS levels closer to each other.       Figure 1 Mean Scores on ABILHAND-Kids with %95 Con dence Interval for each MACS level Mean Scores on ABILHAND-Kids with %95 Con dence Interval for each GMFCS level Mean Scores on CASP subdomains with %95 Con dence Interval for each MACS level Mean Scores on CASP subdomains with %95 Con dence Interval for each GMFCS level Mean Scores on CASP subdomains with %95 Con dence Interval for each CFCS level