Analysis of clinical and psychological characteristics of 225 children with autism spectrum disorder based on the C-PEP-3 scale

Abstract

BACKGROUND

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders that affect children’s social interaction and communication skills and exert a serious effect on children’s perception, language, emotion, and especially social interaction development.

AIM

To determine the clinical and psychological characteristics of children with ASD according to the C-PEP-3.

METHODS

This retrospective study included 225 children with autism aged 2-7 years who were treated in our hospital from 2021 to 2024. The C-PEP-3 scale was used for assessment, and the evaluation results were analyzed.

RESULTS

The comparison of children with ASD in the age groups of < 3.5 years and > 3.5 years revealed significant differences in the scores of imitation, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition development areas (P: Pass) (P < 0.01). However, no significant differences in the scores of perception, emotion, interpersonal relationships, play, sensation, and language (S: Severe) were observed on pathological scales (P > 0.05). The difference in age in the gross motor developmental delay of the scale was the smallest, whereas that of the verbal cognition was the largest, followed by the imitation functional area. An inverse correlation was found between the scores of imitation, perception, hand-eye coordination, and cognitive performance (P) developmental function areas in children with ASD and those of emotion, interpersonal relationships, game and item preferences, sensory patterns, and emotion (S) in the pathological scale (P < 0.05). Fine and gross motor skills were negatively correlated with interpersonal relationships, game and item preferences, and emotions in the pathological scale (P < 0.05). Age was significantly positively correlated with the scores of imitation, perception, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition developmental function areas (P) (P < 0.05). Further, age was not associated with emotions, interpersonal relationships, game and item preferences, sensory patterns, and emotions (P > 0.05). No gender difference was observed between the scores of each developmental area (P) of the scale and the scores of each functional area (S) of the pathological scale.

CONCLUSION

The C-PEP-3 scale reflects the differences in clinical characteristics of children with autism, and the pathological scale is associated with the severity of developmental function areas. The C-PEP-3 scale can be utilized to assess the effect of age changes on children with autism. Attention in rehabilitation should be focused on addressing the pathological behaviors of children with autism.

Key Words: Autism spectrum disorder; Psycho-educational profile; C-PEP-3

Core Tip: Autism spectrum disorder (ASD) exerts a serious effect on the development of children’s perception, language, emotion, and especially social interaction, with substantial individual differences in its clinical characteristics and severity. However, the cause of ASD remains unknown. This study investigated and analyzed the clinical psychological characteristics of ASD reflected by the scale results to early detect ASD, providing a theoretical basis for clinical workers to better understand and apply the C-PEP-3 in evaluating children with ASD and formulating individualized intervention plans.

INTRODUCTION

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders that affect children’s social interaction, communication skills, and behavior patterns[1]. ASD exerts a serious effect on the development of children’s perception, language, emotion, and especially social interaction, with substantial individual variations in its clinical characteristics and severity[2].

The cause of ASD remains unknown. Therefore, the current treatment mainly depends on behavioral and educational interventions in contrast to targeted drug therapy. Scientific assessment is the prerequisite for performing rehabilitation interventions, and the formulation of education plans requires a scale that accurately, truly, comprehensively, and dynamically reflects the level of children’s development. At present, the predominantly used clinical developmental assessment scales are designed according to normal children’s development to obtain intelligence quotient (IQ) scores. However, several children with ASD are unable to complete standardized tests in the required testing context and are mostly considered to have low IQs due to factors such as abnormal behaviors. The test results cannot fully reflect the disease characteristics of children with ASD, causing missed opportunities to receive targeted education. The psycho-educational profile (PEP)[3], designed by Schopler and Reichler in 1979 from a developmental perspective, is specifically for children with autism and associated developmental disabilities and accommodates the unique cognitive and learning styles of children with ASD. The use of developmental and behavioral observation and assessment as well as parent reports accurately reflects the unbalanced and specific developmental abilities, pathological behavioral characteristics, and severity of deviations from normal development in children with ASD and provides individualized education plans for rehabilitation interventions, making it one of the most predominantly used tools to assess the development of children with ASD. The PEP scale, introduced to China in 1995, was named the Chinese version of the PEP (C-PEP) after cross-cultural revision in 1998[4] and then the C-PEP, Third Edition (C-PEP-3) after completing norm domestication in 2014[5]. Research reveals that the scale significantly improves disease symptoms in formulating an individualized education program and assessing the rehabilitation efficacy of autism[6]. Training according to item E of the scale effectively reduces participants’ frustration and rejection reactions, thereby forming a virtuous cycle of education and significantly improving training efficiency[7]. The assessment results of children with ASD with different cognitive levels demonstrate different patterns and serve as a reference for auxiliary diagnosis[8]. Some research reveals that girls with ASD experience more severe impairments in cognitive function, communication, social interaction, and gross and fine motor skills compared to boys, and their self-care ability and adaptive behavior lag behind boys, regarding the gender differences in the ASD clinical characteristics reflected by the C-PEP-3 scale[9]. However, a study indicated no gender difference in the test results of various functional areas for children with ASD with microcephaly[10]. The conclusions are inconsistent. A pronounced imbalance was observed in the developmental quotients of children with ASD[11]. This study aims to investigate and analyze the clinical psychological characteristics of ASD reflected by the scale results, thereby providing a theoretical basis for clinical workers to better understand and apply the C-PEP-3 in evaluating children with ASD and formulating individualized intervention plans.

MATERIALS AND METHODS

Research participants

This study retrospectively selected 225 children aged 2-7 years who were diagnosed with ASD and received treatment in the rehabilitation department of Anhui Provincial Children’s Hospital from February 2021 to April 2024. Inclusion criteria: Patients who meet the autism diagnostic criteria following the Diagnostic and Statistical Manual of Mental Disorders, fifth edition from the American Psychiatric Association[12]. Exclusion criteria: Children with autism aged < 2 years or > 7 years and those suffering from diseases, including childhood schizophrenia and Heller syndrome.

Methods

Personnel with professional assessment qualifications for C-PEP-3 used unified standard instructions and strictly adhered to the operating procedures to test the functional development level of the children. C-PEP-3 consisted of two parts: The pathological behavior scale and the functional development scale[13], totaling 139 items. The functional development scale encompasses 95 items from seven major domains: Imitation (10 items), perception (11 items), fine motor (10 items), gross motor (11 items), hand-eye coordination (14 items), cognitive performance (20 items), and verbal cognition (19 items), with scoring criteria as pass (P), emerge €, and fail (F). The pathological behavior scale consists of 44 items and comprises five major domains: Emotions (6 items), interpersonal relationships (7 items), game and item preferences (6 items), sensory response (14 items), and language (11 items), with scoring criteria as none (A), mild (M), and severe (S). Finally, the developmental level of children was identified based on the number of P in each developmental area corresponding to the developmental age, whereas the pathological scale was expressed by the number of S in each developmental area.

Statistical analyses

Statistical Package for the Social Sciences version 21.0 statistical software was utilized for data processing. Continuous data were presented as mean ± SD, and a two-sample t-test was conducted for between-group comparison. Count data are expressed as rates or component ratios. Correlation analysis was conducted with the Pearson correlation method. P values of < 0.05 indicated statistically significant differences.

RESULTS

General data

Table 1 presents the general demographic characteristics of children with ASD. This study included 225 children with ASD aged 2-7 years, consisting of 188 (83.6%) males with an average age of 55.80 ± 14.76 months and 37 (16.4%) females with an average age of 53.76 ± 13.20 months. This gender distribution reflects the well-documented gender disparity in ASD diagnoses, where males are diagnosed more frequently than females[14]. No notable inter-group differences were determined in age between children with ASD of different sexes (P > 0.05).

Table 1 General information.

	Sex (mean ± SD)		t	P value
	Male (n = 188)	Female (n = 37)
Age	4.65 ± 1.23	4.48 ± 1.10	0.773	0.440

Gender differences in scores of various functional areas of the scale

The results indicated no significant gender differences in imitation, perception, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition (P) scores in children with ASD, as well as in emotion, interpersonal relationship, game and item preference, sensory pattern, and language functional area (S) scores in the pathological scale (P > 0.05, Table 2).

Table 2 Comparison of gender differences in scores of various functional areas.

Categories	Sex (mean ± SD)		t	P value
	Male (n = 188)	Female (n = 37)
Imitation (P)	5.05 ± 2.39	4.68 ± 2.27	0.885	0.377
Perception (P)	6.61 ± 1.67	6.11 ± 1.71	1.653	0.100
Fine motor (P)	4.74 ± 1.87	4.81 ± 1.93	-0.211	0.833
Gross motor (P)	8.79 ± 1.47	8.68 ± 1.38	0.446	0.656
Hand-eye coordination (P)	7.05 ± 2.31	6.81 ± 2.20	0.588	0.557
Cognitive performance (P)	6.95 ± 3.97	6.41 ± 3.35	0.785	0.434
Verbal cognition (P)	5.85 ± 3.73	5.05 ± 3.82	1.183	0.238
Emotions (S)	1.16 ± 1.29	1.30 ± 1.05	-0.612	0.541
Interpersonal relationships (S)	1.45 ± 1.59	1.32 ± 1.20	0.445	0.657
Game and item preferences (S)	1.26 ± 1.51	1.27 ± 1.54	-0.055	0.956
Sensory patterns (S)	2.38 ± 1.92	2.54 ± 2.21	-0.460	0.646
Language (S)	2.95 ± 2.35	3.43 ± 2.19	-1.160	0.247

Variations in scores in various functional areas of the scale across different age groups

Significant differences were observed in imitation, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition development (P) scores between children aged < 3.5 years and those aged > 3.5 years with ASD (P < 0.01) but with no marked differences in perception, emotions, interpersonal relationship, game and item preference, sensory pattern, and language (S) scores (P > 0.05, Table 3).

Table 3 Comparison of scores between different age groups in various functional areas.

Categories	Age groups (mean ± SD)		t	P value
	< 3.5 years old (n = 113)	> 3.5 years old (n = 112)
Imitation (P)	5.55 ± 2.37	4.43 ± 2.25	3.637	0.000b
Perception (P)	6.69 ± 1.71	6.36 ± 1.64	1.489	0.138
Fine motor (P)	5.47 ± 1.87	4.03 ± 1.59	6.240	0.000b
Gross motor (P)	9.21 ± 1.31	8.33 ± 1.46	4.766	0.000b
Hand-eye coordination (P)	7.98 ± 2.42	6.04 ± 1.66	7.041	0.000b
Cognitive performance (P)	7.73 ± 4.26	5.99 ± 3.23	3.445	0.001b
Verbal cognition (P)	6.64 ± 3.93	4.79 ± 3.32	3.798	0.000b
Emotions (S)	1.27 ± 1.36	1.09 ± 1.12	1.113	0.267
Interpersonal relationships (S)	1.46 ± 1.51	1.39 ± 1.55	0.330	0.742
Game and item preferences (S)	1.32 ± 1.54	1.20 ± 1.48	0.606	0.545
Sensory patterns (S)	2.49 ± 2.21	2.32 ± 1.69	0.631	0.529
Language (S)	2.88 ± 2.41	3.18 ± 2.25	-0.974	0.331

^bP < 0.01.

Comparison of the difference between the equivalent age of the developmental functional area of the scale and the actual age

A lag was observed between the equivalent age and actual age in various developmental function areas of children with ASD, with the smallest, largest, and second largest age differences found in gross motor, cognitive performance, and imitation, respectively (Table 4).

Table 4 Difference between the equivalent months of age and the actual age in each developmental function area of C-PEP-3.

Project (months)	Minimum	Maximum	Mean	Standard deviation	Median
Imitation	-13.800	56.800	20.553	14.064	19.400
Perception	-24.680	58.000	16.375	14.934	16.000
Fine motor	-21.680	52.800	19.433	13.291	18.200
Gross motor	-21.600	51.400	13.038	13.714	12.600
Hand-eye coordination	-27.600	49.600	14.447	12.496	14.400
Cognitive performance	-26.600	63.800	21.002	15.588	20.200
Verbal cognition	-26.680	64.800	17.565	15.015	16.600

Association between the scale developmental function score and the pathological scale score

Pearson correlation analysis revealed the presence of a negative correlation between imitation, perception, hand-eye coordination, and cognitive performance scores in the developmental function areas (P) of children with ASD and emotion, interpersonal relationship, game and item preference, sensory pattern, and language scores in the pathological scale (S) (r ranging from -0.174 to -0.428, P < 0.05). Fine motor and gross motor were inversely related to interpersonal relationships, game and item preferences, and emotions in the pathological scale (r ranging from -0.136 to -0.249, P < 0.05, Table 5).

Table 5 Relationship between the score of developmental functional areas and the score of the pathological scale.

Categories	Imitation (P)	Perception (P)	Fine motor (P)	Gross motor (P)	Hand-eye coordination (P)	Cognitive performance (P)	Verbal cognition (P)
Emotions (S)	-0.216b	-0.184b	-0.118	-0.021	-0.208b	-0.281b	-0.210b
Interpersonal relationships (S)	-0.319b	-0.310b	-0.249b	-0.149a	-0.313b	-0.413b	-0.274b
Game and item preferences (S)	-0.269b	-0.280b	-0.166a	-0.136a	-0.291b	-0.379b	-0.236b
Sensory patterns (S)	-0.174b	-0.245b	-0.108	-0.068	-0.166a	-0.212b	-0.048
Language (S)	-0.326b	-0.256b	-0.196b	-0.235b	-0.311b	-0.428b	-0.283b

^aP < 0.05.

^bP < 0.01.

Correlation between the scores of each functional area of the scale with age

Table 6 shows Pearson correlation analysis, revealing that age was positively associated with imitation, perception, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition development (P) scores of functional areas (r = 0.331, 0.204, 0.485, 0.422, 0.557, 0.318, and 0.352, respectively, P < 0.05). Additionally, age exhibited no association with emotions, interpersonal relationships, game and item preferences, sensory patterns, and language (P > 0.05).

Table 6 Relationship between scores of functional areas and age.

Categories	Mean	SD	r
Imitation (P)	4.991	2.372	0.331b
Perception (P)	6.524	1.683	0.204b
Fine motor (P)	4.751	1.876	0.485b
Gross motor (P)	8.773	1.454	0.422b
Hand-eye coordination (P)	7.013	2.29	0.557b
Cognitive performance (P)	6.862	3.871	0.318b
Verbal cognition (P)	5.72	3.748	0.352b
Emotions (S)	1.182	1.249	0.011
Interpersonal relationships (S)	1.427	1.528	0.01
Game and item preferences (S)	1.258	1.51	0.013
Sensory patterns (S)	2.404	1.964	0.01
Language (S)	3.027	2.33	-0.07

^bP < 0.01.

DISCUSSION

This study revealed a male-to-female ratio of ASD of 5: 1, which is consistent with the previously reported incidence ratio of 4-5: 1 for males and females[15], reflecting a high incidence of ASD among males. However, some controversies remain regarding the gender difference in the prevalence of ASD. Some researchers have indicated that the current diagnostic criteria and tools mainly depend on male biological characteristics, causing late or missed diagnoses of females with ASD[16]. Several explanatory models have been proposed for ASD to explain the etiology of gender differences in prevalence rates, including the brain differences model (BDM). BDM is the most predominantly and extensively studied model. The extreme male brain hypothesis proposes that the male and female brains are hardwired differently in BDM, causing males to demonstrate a relative advantage in systematization and females to show a relative advantage in empathy[17]. Therefore, considering this, males may be more susceptible to autism ASD traits stemming from an extreme form of the male neurodevelopmental model, and females may be less susceptible to ASD because of their innate ability to empathize and socialize. Girls have performed better than boys in terms of fine motor and personal-social skills regarding clinical features[18,19]. Males with ASD demonstrate more external and obvious repetitive and stereotyped behaviors than females[20], whereas girls with ASD perform worse than boys with ASD in hand-eye coordination and performance areas[21]. Females and males with ASD demonstrate similar severity in ASD-specific behaviors when accompanied by intellectual disabilities[22]. Cognitive decline is a crucial factor affecting gender differences in social communication skills and behavioral characteristics in ASD[23]. Reynolds et al[24] revealed no association between the developmental quotient level of each functional area of the GESELL scale in children in the ASD group, the suspected ASD group, and the GDD group with gender. Lai et al[25] did not reveal gender differences in problem behaviors, personal self-care abilities, and adaptive behaviors in the PEP-3 assessment results either. The comparison in this study demonstrates no gender differences in different functional areas. The inconsistency of the above conclusions may be associated with factors, such as ASD severity, between genders in the sample included in this study, as well as factors, such as the age distribution of research participants and developmental assessment tools in different regions. The sample size was expanded and clinical characteristics were specified for further observation and analysis in subsequent studies.

The development of different abilities in normal children demonstrates corresponding behavioral patterns, and the performance of different abilities should be at the same level and mutually affected. The developmental level of children with ASD usually greatly varies, with significant differences. This study revealed developmental differences in various functional areas of children with ASD. Among them, the cognitive understanding of language by children with ASD is one of the abilities with the most significant delay in development[11]. Their cognitive grasp of language is in a state of mechanical memory, which frequently results in their inability to understand the explicit connotations. Further, operators issued many test items through language, which requires children with ASD to have a certain ability to understand spoken language to make a correct response. Multiple factors help to a relatively severe cognitive performance. Further, impaired imitation ability is one of the core deficits of children with ASD[26]. Imitation exhibits both learning and social functions. Facial expression, body movement, and even object or movement imitations exist in the first year of life. However, children with ASD experience delayed development of motor imitation ability in the early postnatal period[27]. Children’s imitation ability is closely associated with their language development and plays a crucial role in promoting language development. Some scholars have proposed that the imitation level is the best predictor of the two-year language therapy response in children with ASD[28]. Evidence indicates that children with ASD have delayed motor and coordination development abilities in the early years[29,30] and persist throughout their entire life cycle[31], in terms of stereotypic movement disorder (such as clapping hands), motor control, and coordination. A longitudinal study on 209 autistic children revealed that the gross motor skills of children with ASD at 2 years of age predict their expressive and receptive language development at 9 years of age[32]. Gross motor skills are related to IQ, social communication, and language in children with ASD[33]. Further, children with ASD in this study were lagging in gross motor development but less impaired than other functions, which to some extent results in parents seeking medical attention for their children’s language problems, but neglecting their developmental coordination in motor development. Gross motor skills are used as one of the symptom indicators for predicting ASD, and research in recent years has been gradually increasing. Adopting personalized intervention measures according to the characteristics of the assessment that improve the various developmental abilities of patients with ASD is an important goal of rehabilitation intervention.

Furthermore, the present research revealed that emotion, interpersonal relationship, game and item preference, sensory pattern, and emotion (S) scores in ASD pathological behaviors were negatively correlated with imitation, perception, hand-eye coordination, cognitive performance, and total developmental function scores, consistent with the results of Yenkoyan et al[34]. All of these indicate that the severity of pathological behavior in children with ASD impedes the development of their developmental functions, especially in imitation, cognitive performance, and verbal expression of the most serious typical symptoms of ASD. Abnormal pathological behavior is one of the crucial factors that hinder the development of children with ASD. Pathological behavior, which affects disease severity[35], is more prevalent in children with developmental disabilities[36], affecting the development of children’s social adaptation behaviors[37], and significantly increasing the pressure on parents for care at home and the risk of being excluded in school education[38]. Prioritizing the handling of problem behaviors and promptly incorporating them into the ASD intervention plan is of particular importance to alleviate the developmental disorders of children with ASD.

Children with ASD aged > 3.5 years demonstrated lower scores than those < 3.5 years old in the developmental function areas of imitation, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition. Meanwhile, the conditions in the function areas of imitation, perception, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition development of children with ASD became more severe as age increased. This indicates that the developmental ability of children with ASD is more significantly affected by the increase in age. This may be because most of the samples in this study were newly diagnosed and had not received systematic intervention training. Older children with ASD have more severe symptoms, indicating that the functional development of ASD will remain restricted as age increases without intervention, emphasizing the importance of early detection and early intervention. Clinicians should not only consider the traditional diagnostic manuals for ASD in the developmental domain when diagnosing and treating children with ASD but should also assess the presence of motor developmental disorders.

This study has limitations. First, the relatively modest sample was limited to children within China, requiring the inclusion of a different international population in a follow-up study to improve the robustness and external validity of the results. Meanwhile, physical development and disease severity are equally capable of causing differences in scores for the children themselves, and failure to categorize patients accordingly may cause some bias in the results. Additionally, demographics, such as socioeconomic status and parental education level, potentially affect the developmental trajectories of children with autism, and such missing data could create a significant gap. Future studies are recommended to incorporate these key demographic variables to facilitate a more in-depth exploration of the interplay between own development or family background and motor development. Additionally, future studies need to utilize a large sample size longitudinal study design that includes a comprehensive assessment of intellectual and motor skills, aiming to determine the complex mechanisms behind the observed developmental delays and challenges in children with ASD.

CONCLUSION

The pathological behaviors of the core symptoms of ASD (such as restricted, repetitive, and stereotyped behaviors, interests, and activity patterns) are pervasive over a long period and are unlikely to significantly improve in the short term[39]. This study reveals no significant correlation between the age of children with ASD and the emotion, interpersonal relationship, game and item preference, sensory pattern, and language scores of the pathological scale, indicating that pathological behaviors do not significantly change with age and are likely to persist, thereby severely affecting the development and growth of children with ASD. This reminds us of the importance of early correction of abnormal pathological behaviors in children with ASD. However, the samples in this study are focused on children with ASD aged 2-7 years. The sample age was further extended for observation in the future.