Parental Stress and ASD

Abstract

The objectives of this study were (a) to evaluate parental stress in parents of children with autism spectrum disorders (ASD group) and compare it with the stress in parents of children with typical development (comparison group); (b) to study the relationship between parental stress, autism severity, and both verbal and performance IQ; and (c) to study the relationship between parental stress and resilience. Parental stress in the ASD group was clinically significant and higher than in the comparison group. The child’s autism severity was a significant predictor of parental stress related to the child’s distractibility and hyperactivity. The child’s verbal IQ was a significant predictor of parental stress in the child domain. Only for the ASD group, the child’s performance IQ was a significant predictor of parental stress, and parental resilience was a significant predictor of parental stress related to depression and competence variables. These results and implications for intervention are discussed.

Keywords

autism spectrum disorders symptom severity IQ parental stress resilience

Introduction

Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by deficits in language and communication, social interaction, and play and imagination, with the presence of restricted interests and stereotyped behaviors (American Psychiatric Association [APA], 2013). Studies of parents raising children with ASD document elevated stress levels (e.g., Estes et al., 2009; Wolf, Noh, Fisman, & Speechley, 1989). The theoretical concept of stress proposed by Folkman and Lazarus (1985) considers stress as an individual and subjective process that results from the interaction of an individual with his or her environment. When individuals deem that environmental stressors have overwhelmed their resources, they engage in coping mechanisms to restore functioning. However, if the coping mechanisms cannot meet the demands, the outcome is stress. The stress process includes four components: an external event (stressor), a cognitive appraisal of this event, coping mechanisms to reduce the noxiousness of this event, and consequential effects on the mind and body, or the stress reaction (Lazarus, 1993). From this perspective, parental stress arises when a family is unable to restore adequate functioning following the introduction of a stressor (related to parenting) by engaging in their regular family-coping strategies (Hayes & Watson, 2013).

Abidin’s (1992) theoretical perspective on parental stress—based on an ecological and systemic approach to family relations—considers that the parental stress produced by child-rearing is based on certain characteristics of the child and the parents (Abidin, 1995). The child’s characteristics include behavior problems, whereas the parents’ characteristics involve some personality features, the accessibility and perceived availability of resources, and their feelings of competence in parenting. Thus, according to Abidin (1992), the parents’ beliefs and expectations are mediators between the events (potential stressors) and the perceived parental stress. Hence, this cognitive activity is a key element in the assessment of a situation or an event (potentially stressful), as well as in the evaluation of the coping mechanisms that would allow them to deal with it more or less successfully. These evaluative processes are considered very important in perceived parental stress, to the extent that raising a child with ASD is not necessarily associated with parental stress because it greatly depends on these evaluation processes.

However, various studies point out that parents of children with ASD present significantly higher levels of chronic stress than parents of children with typical development (e.g., Brobst, Clopton, & Hendrick, 2009; Hoffman, Sweeney, Hodge, Lopez-Wagner, & Looney, 2009; Lee et al., 2009; Rao & Beidel, 2009; Wolf et al., 1989). These findings yielded a large effect size in a recent meta-analysis conducted by Hayes and Watson (2013). The high stress levels in parents of children with ASD are seen in different countries: for example, Anglo-Saxon (Hoffman et al., 2009; Osborne & Reed, 2009), Spanish (Pozo, Sarriá, & Méndez, 2006), and Chinese-speaking countries (Wang et al., 2013). Parental stress is an important variable related to parents’ behavior (Deater-Deckard, 1998). Those parents who show high levels of parental stress usually perceive their children as difficult and show patterns of ineffective disciplining and dysfunctional parenting, frequently leading to greater difficulties in the child (Abidin, 1992; Östberg & Hagekull, 2000). In these conditions, stress negatively influences the emotional climate, maintenance of a social network, leisure activities, and interactions within the family nucleus (Bebko, Konstantareas, & Springer, 1987).

Some studies have investigated the factors related to the stress experienced by parents of children with ASD. Thus, the severity of the symptoms associated with the disorder and the child’s behavior problems have been associated with parental stress in a large number of studies (e.g., Brobst et al., 2009; Hoffman et al., 2009; Lecavalier, Leone, & Wiltz, 2006; Lyons, Leon, Phelps, & Dunleavy, 2010; McStay, Dissanayake, Scheeren, Koot, & Begeer, 2013) in different countries (e.g., Spain: Pozo & Sarriá, 2014; Greece: Konstantareas & Papageorgiou, 2006; and China: Wang et al., 2013) and from a developmental perspective (Osborne & Reed, 2009; Zaidman-Zait et al., 2014). According to a theoretical model proposed by Hastings (2003), the relationship is bidirectional: The child’s problematic behaviors lead to parenting stress, which, in turn, affects parenting behaviors, which then increase the child’s problem behaviors. Children with ASD, even those who are high functioning or those who do not present especially disruptive behavior, often exhibit very unusual behaviors, such as stereotyped speech and odd or ritualistic behaviors, which can be experienced by the parents as particularly stressful (Tomanik, Harris, & Hawkins, 2004), especially if they occur in certain situations such as in public. Specifically, two of the key diagnostic traits of ASD have been identified as particularly stressful for parents: impairments in social communication (e.g., Bebko et al., 1987) and restricted and repetitive behaviors (e.g., Richardson, 2010).

Another factor that has been studied in relation to stress in parents of children with ASD is the child’s level of intellectual ability, given that it is related to his or her capacity for autonomy, potential to learn, ability to communicate, and manifestation of problematic behaviors. Nevertheless, results from studies relating parental stress to intellectual functioning are not conclusive (Rao & Beidel, 2009; Totsika, Hastings, Emerson, Lancaster, & Berridge, 2011). According to Lee et al. (2009), high functioning is not equal to adaptive functioning. In addition, some factors related to parents’ characteristics have also been associated with parental stress. Abidin (1992) conferred great importance to personality factors, mental health (depression, anxiety . . . ), the partners’ relationship, and emotional problems that parents can suffer even before the child’s birth. External factors, such as economic conditions and perceived social support, would also modulate the parental stress experienced (Ekas, Lickenbrock, & Whitman, 2010; Pozo & Sarriá, 2014).

As noted above, not all parents raising a child with ASD report high stress levels. An event is experienced as stressful based on the meaning one attributes to the event and the perceived coping resources. In this vein, resilience has emerged as a growing field of interest in family research, as a means to emphasize healthy and positive family functioning in the face of chronic stress (Hayes & Watson, 2013). Resilience has been defined as “a dynamic process encompassing positive adaptation within the context of significant adversity” (Luthar, Cicchetti, & Becker, 2000, p. 545). A family is resilient if it shows strength when facing adversity and manages to function well and come out stronger. Some studies (e.g., Bayat, 2007; Cripe, 2013) have shown that, despite challenges faced by families of children with ASD, a considerable number of these families show evidence of resilience. These families react to adversity by becoming stronger and having a more positive outlook. A recent review of the resilience literature on parents of children with ASD (Bekhet, Johnson, & Zauszniewski, 2012) concluded that those who possess indicators of resilience are better able to handle the challenge of raising a child with ASD.

The current study had several aims. The first objective was to evaluate the perceived parental stress (in several domains related to the child and the parents’ characteristics) in parents of children with ASD (ASD group) and compare it with that of parents of children with typical development (comparison group). The second objective was to study the relationship between perceived parental stress and several characteristics of the child: severity of autistic symptoms (in the ASD group), verbal IQ, and performance IQ, to find out whether the degree of autism (in the ASD group), linguistic skills, and intellectual ability were significant predictors of parental stress. The third objective was to study the relationship between perceived parental stress and the parental characteristic of resilience, to find out whether resilience was a significant predictor of parental stress in the ASD group.

To our knowledge, this is the first article about ASD in which, within the same study, the relationships between parental stress and different variables of both the child (severity of autistic symptoms, verbal IQ, and performance IQ) and the parents (resilience) have been analyzed, using the Parenting Stress Index (PSI) scale (a comprehensive and validated measure of parenting stress) and a comparison group of children with typical development matched one to one with the ASD group on chronological age, gender, and performance IQ. Specifically, in our study the role of ASD has been isolated from intellectual functioning, by comparing parents of children with and without ASD matched on performance IQ. This contribution goes beyond the published studies on the subject. Moreover, various diagnostic criteria were considered in selecting the children for the ASD group, as described in the “Participants” section, strengthening the methodological contribution of this article.

Method

Participants

The participants consisted of 84 families: 42 with a child diagnosed with ASD (ASD group) and 42 with a child with no diagnosis (comparison group). The children’s ages ranged from 5 to 8 years old, and their performance IQ ranged from 75 to 135 on the Raven test (Raven, 1996). This is a non-verbal test to obtain an estimation of reasoning ability, where the subject is asked to identify the missing element that completes a pattern. Children in the ASD group had a clinical diagnosis of ASD, according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR; APA, 2000), and they met the diagnostic criteria for Level 2 of the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; APA, 2013). They were diagnosed by neuropediatric services from different hospitals in the national health system. These neuropediatric services were responsible for checking compliance with these diagnostic criteria, and they derived the children who met the diagnostic criteria to early care units, where the diagnosis was confirmed using more specific instruments, such as the Autism Diagnostic Observation Schedule (ADOS). Moreover, all of them obtained an autism index (AI) score ≥85 on the Gilliam Autism Rating Scale, Second Edition (GARS-2), indicating a high likelihood of the disorder (Gilliam, 2006). The scores ranged from 85 to 165 (M = 99.80, SD = 11.30). For GARS-2 subscale standard scores, Stereotyped Behavior ranged from 3 to 18 (M = 8.72, SD = 2.32), Social Interaction ranged from 2 to 17 (M = 10.12, SD = 2.74), and Communication ranged from 3 to 19 (M = 11.40, SD = 2.4). The children in the ASD group were attending school in Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH)–integrated classrooms in state schools in Valencia (Spain). These classrooms are specific units integrated in ordinary public schools where students with disorders affecting language and communication are enrolled. However, the children in the comparison group were children with typical development, without any clinical diagnosis, and they attended the same schools as the ASD Group, but in the ordinary modality.

To obtain this sample, a selection was made using the following process. The ASD group initially consisted of 67 children, but 8 were ruled out because they were not able to understand the Raven test. The comparison group was initially comprised of 350 children. The two groups of children were matched one to one on IQ performance, chronological age, and gender, so that of the initial 350 children without ASD, 61 were selected. Parents of all the selected children were asked to fill out a series of questionnaires and participate in an interview with the school psychologist. Based on the information collected from the families who attended the meeting with the school psychologist and filled in the questionnaires, the two groups were finally formed.

Table 1 includes the children’s demographic information for the ASD and comparison groups. There were 38 boys and 4 girls in the ASD group and 33 boys and 9 girls in the comparison group. Both groups had a mean age of around 80 months and a mean performance IQ (measured by the Raven test) around 100. Statistically significant differences were not found between the two groups of children on gender (χ² = 2.27, p = .131, η² = .027), chronological age, F(1, 82) = 1.16, p = .280, $η_{p}^{2}$ = .014; or performance IQ, F(1, 82) = 0.03, p = .850, $η_{p}^{2}$ = .000. Nonetheless, statistically significant differences were found on verbal IQ, F(1, 82) = 63.62, p = .000, $η_{p}^{2}$ = .437, as it was higher in the comparison group than in the ASD group. Moreover, both groups of parents answered a set of items, based on the DSM-IV-TR criteria, to evaluate their child’s inattention, hyperactivity, and impulsivity. Statistically significant differences between the two groups of children were found on Inattention, F(1, 82) = 27.66, p = .000, $η_{p}^{2}$ = .252, and Hyperactivity/Impulsivity, F(1, 82) = 24.16, p = .000, $η_{p}^{2}$ = .228, with more attention deficit hyperactivity disorder (ADHD) symptoms in the ASD group than in the comparison group. Parents also reported on their children’s disruptive behavior. This type of behavior was present in 36.58% of the children in the ASD group and 21.42% of the children in the comparison group, with no statistically significant differences found between the two groups (χ² = 2.31, p = .128, η² = .027). They also reported other medical conditions, such as digestive problems, constipation, and epilepsy (see Table 1).

Table 1.

Children’s Demographic Information for ASD and Comparison Groups.

Demographic	ASD (n = 42)	Comparison (n = 42)
Gender
Female (%)	9.50	21.40
Male (%)	90.50	78.60
Age (in months; M)	77.60	81.50
Performance IQ (M)	99.57	100.36
Verbal IQ (M)	68.62	97.45
Inattention (M)^a	6.00	2.64
Hyperactivity/impulsivity (M)^b	5.59	2.90
Disruptive behavior (%)	36.58	21.42
Digestive problems (%)	11.10	2.40
Constipation (%)	14.40	14.40
Epilepsy (%)	4.80	2.40

Note. ASD = autism spectrum disorders; DSM-IV-TR = Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; APA, 2000).

^aNumber of ADHD Inattention Symptoms (DSM-IV-TR). ^bNumber of ADHD Hyperactivity/impulsivity Symptoms (DSM-IV-TR).

Table 2 includes family demographic information for the ASD and comparison groups. In the two groups, most of the participants were mothers (around 80%), while fathers were a minority. The mean age of the parents was about 39 (range = 25–49). Statistically significant differences were not found between the two groups of parents on gender (χ² = .15, p = .694, η² = .001) or age, F(1, 82) = 0.65, p = .419, $η_{p}^{2}$ = .008. About 57% of the parents in the ASD group and 74% of the parents in the comparison group had secondary or higher education. Most of the parents in the two groups were married or living together (around 80%). There were more single parents in the ASD group (9.54%) than in the comparison group (2.38%), but more divorced or separated parents in the latter (19.08%) than in the former (9.54%). Most of the parents in the two groups (almost 90%) reported having medium or low income, although more parents reported low income in the ASD group (19.08%) than in the comparison group (7.14%). Finally, the mean number of children in the family was about 1.90 in both groups.

Table 2.

Family Demographic Information for ASD and Comparison Groups.

Demographic	ASD (n = 42)	Comparison (n = 42)
Parents’ response
Fathers (%)	17.90	21.40
Mothers (%)	82.10	78.60
Parental age (M)	38.86	39.62
Parents’ education
No studies (%)	2.38	0
Primary (%)	28.56	26.18
Secondary (%)	26.18	33.32
University (%)	31.00	40.50
Unknown (%)	11.88	0
Parents’ marital status
Single (%)	9.54	2.38
Married (%)	76.16	66.66
Divorced/separated (%)	9.54	19.08
Living together (%)	4.76	11.88
Annual family income
No income (%)	11.88	11.88
Low income (%)	19.08	7.14
Medium income (%)	64.26	80.98
High income (%)	2.38	0
Children (M)	1.81	1.95

Note. ASD = autism spectrum disorders.

Procedures

This study is part of a broader investigation that was approved and funded by the University of Valencia and had the authorization of the agency responsible for primary education. All of the Valencian state schools with TEACCH-integrated classrooms were invited, via an informational meeting, to participate in the research. From the schools that voluntarily agreed to participate, some classrooms of 5- to 8-year-old children were selected. The parents of the children gave written informed consent to participate in the research. Children’s performance IQ and verbal IQ were individually evaluated by the school psychologist in a noise- and distraction-free office. Parents of all the selected children were asked to have an interview with the school psychologist to provide the necessary information about their children and fill out the questionnaires. Information was gathered about their children’s characteristics, including ADHD symptoms, behavior, and health data (see Table 1), as well as family demographic data (see Table 2). Information about the ADHD symptoms was added because of the frequent association between ASD and ADHD, which has even been recognized in the DSM-5 (APA, 2013), and the possible influence of the comorbid presence of ASD + ADHD on parental stress. Furthermore, the school psychologist interviewed parents to get information about parental stress, by administering the PSI (Abidin, 1995), and resilience, by administering the Resilience Scale (RS; Wagnild & Young, 1993) in the case of the parents of the ASD group. In addition, information about autism severity was obtained from the GARS-2, by means of an interview with the parents of the ASD group.

Measures

Raven Color Progressive Matrices Scale (CPM)

This scale provides one of the best estimations of the deductive capacity and “g” factor of general intelligence. It is a non-verbal test that contains 36 elements where the child must choose missing pieces from a series of between six and eight proposals. It is administered to children between 4 and 9 years old. We have used the performance IQ score provided by the test (Raven, 1996).

Peabody Picture Vocabulary Test (PPVT)

This instrument is widely used to assess vocabulary knowledge in children and adults. It consists of 192 items: The examiner names a word (noun, verb, adjective, etc.), and the child has to point out an image from four images presented. We have used the verbal IQ score provided by the test (Dunn, Dunn, & Arribas, 2006).

GARS-2

The GARS-2 (Gilliam, 2006, the Spanish version) is a standardized, professional, and parent-report instrument to evaluate autism symptoms in people between 3 and 22 years old. Based on the APA (2000) definitions of autism and the DSM-IV-TR diagnostic criteria, the scale consists of 42 items, responded to on a Likert-type scale, that measure three domains associated with the disorder: Stereotyped Behavior, Communication, and Social Interaction (M = 10 and SD = 3 for each). The combined scores on these subscales yield an AI score (M = 100 and SD = 15), with higher scores indicating a greater degree of autism. Gilliam (2006) reported AI scores ≥85 for 90% of a normative sample of 1,107 people diagnosed with autism. Its internal consistency was high (Cronbach’s αs were .94 for the AI, .84 for Stereotyped Behavior, .86 for Communication, and .88 for Social Interaction). For the current study, Cronbach’s alphas were, respectively, .84, .86, .76, and .70. The scale’s criterion validity with the Autism Behavior Checklist was high (.94). GARS-2 is a widely used tool to assess ASD symptoms, and it has been adapted and validated in different countries, with results that show good psychometric characteristics.

PSI

The PSI (Abidin, 1995; translation by Grau, 2007) is a comprehensive and standardized measure designed to evaluate parenting stress. It is the most widely used instrument to evaluate parental stress in parents of children with ASD (Hayes & Watson, 2013). It has strong psychometric properties, and its validity is supported in numerous studies described in the manual across different disability groups. In our study, we used the translation by Grau (2007), in which both forward and backward translations were done, and the equivalence of the translation was first reviewed by eight expert panel members. The PSI questionnaire has a total of 120 items, responded to on a Likert-type scale, that evaluate parental stress in two domains: the Child Domain and the Parent Domain. The Child Domain refers to the stress stemming from caring for the child and from characteristics of the child that make raising him or her more difficult. The Parent Domain refers to the stress derived from the parents’ own characteristics and functioning, which can keep them from appropriately performing their parental role. Each of these two domains contains various subscales (or variables). The Child Domain contains the following variables: distractibility/hyperactivity, child behaviors associated with ADHD; adaptability to changes and transitions; reinforces parent, perception or feelings of the child as a source of reinforcement; demandingness, the child’s demands, requirements and difficulties; mood, the child’s negative mood state; acceptability, parents’ expectations about the physical, intellectual, and emotional characteristics of their child. The Parent Domain includes the following variables: depression, presence of sadness and feelings of discontent with themselves and with their life circumstances; competence, parents’ feelings of competence about their role as parents; role restriction, limitations or restrictions on the parental role; isolation (social); attachment, feeling closeness or emotional bonding with the child; health, parental health problems; and spouse, active and emotional support from the partner in taking care of the child. The PSI provides a score for each variable, as well as a global score for each domain (Child and Parent). Furthermore, various additional items refer to possible sources of stress in the past 12 months (stressful life events), from which a score called Life Stress can be obtained. On all these variables, direct scores and percentiles have been used. Scores above the 90th percentile are indicative of significant stress and may require professional consultation (Abidin, 1995). A high internal consistency has been reported for both domains. For the present study, the internal consistencies, as assessed by Cronbach’s alpha, were .92 for the Child Domain and .93 for the Parent Domain.

The RS

This scale was designed to identify personal qualities that benefit a resilient individual adaptation (Wagnild & Young, 1993; adaptation by Heilemann, Lee, & Kury, 2003). The original scale was based on the story of 24 American women who had favorably overcome the most adverse situations in their lives, and it was applied to a sample of 1,500 people. The RS consists of 25 items responded to on a Likert-type scale. The total score is obtained from the sum of the scores on the scale, and the theoretical values range from 25 to 175: Scores higher than 145 are indicative of high resilience, scores less than 120 indicate low resilience, and scores from 120 to 145 show moderate resilience. The RS has been adapted and validated in several countries, obtaining good psychometric properties. We used the Spanish version (ES), adapted by Heilemann et al. (2003), which showed a high internal consistency (Cronbach’s α = .93), the same as in the current study.

Own Questionnaires

We used a health questionnaire to ask parents about the presence of possible conditions in their child, such as symptoms of ADHD—using a set of items based on the criteria included in the DSM-IV-TR (APA, 2000)—disruptive behavior, digestive problems, constipation, and epilepsy (see Table 1), and a sociodemographic questionnaire to ask parents about their gender, age, educational level, marital status, income level, and number of children (see Table 2).

Results

Analyses were performed using the SPSS statistical package, version 19 for Windows. MANOVAs were carried out, to compare the parental stress of the parents of the ASD group with that of the parents of the comparison group. Then, Pearson’s correlation analyses were carried out between the parental stress variables and both the children’s (severity of autism, verbal IQ, and performance IQ) and parents’ characteristics (resilience). Next, any statistically significant relationships were submitted to simple regression analysis for further exploration. Finally, to study the contribution of each of the different variables within a joint model, two multiple regression analyses were performed for the ASD group: one for the PSI Parent Domain variable and the other for the PSI Child Domain variable. Of all the correlations and regressions carried out, we only mention those that were statistically significant.

Group Differences in Parental Stress

For the first objective, MANOVAs were performed between the two groups of parents: one on the variables of the PSI Child Domain subscale scores and another on the variables of the PSI Parent Domain subscale scores. For the Child Domain, statistically significant differences between the two groups were found, Wilks’s λ = .51, F(6, 77) = 11.97, p = .000, $η_{p}^{2}$ = .483, on all the variables (including the global index), except the reinforces parent variable (see Table 3). The ASD group reported higher levels of stress than the comparison group. A comparison of these results with the values reported by Abidin (1995) revealed that the percentiles of the ASD group were situated at values around 90 (in the case of the global index, 97), with the exception of the reinforces parent variable, which had a value of 70. In the comparison group, the percentiles were located around 50, with a value of 39 in the case of the global index (see Table 3).

Table 3.

Means, Standard Deviations, and F Values, for PSI Child Domain Subscales for ASD and Comparison Groups.

	ASD (n = 42)			Comparison (n = 42)
PSI	M	SD	Percentile	M	SD	Percentile	F(1, 82)	p	$η_{p}^{2}$
Distractibility/hyperactivity	30.45	5.75	90	23.62	5.19	50	32.65	.000**	.285
Adaptability	31.31	7.98	92	22.67	6.10	38	31.05	.000**	.275
Reinforces parent	10.79	4.47	70	9.55	2.60	60	2.40	.125	.028
Demandingness	25.76	6.29	96	17.43	5.13	50	44.22	.000**	.350
Mood	11.95	3.74	85	8.76	2.75	45	19.79	.000**	.194
Acceptability	21.19	5.58	99	12.38	4.66	52	49.37	.000**	.376
Global Index child	133.65	94.40	97	28.04	20.21	39	61.57	.000**	.429

Note. PSI = Parenting Stress Index; ASD = autism spectrum disorders.

p < .05. **p < .001.

For the Parent Domain, statistically significant differences between the two groups were also found, Wilks’s λ = .75, F(8, 75) = .3.09, p = .005, $η_{p}^{2}$ = .248, on all the variables (including the global index), except the depression and attachment variables and the Life Stress score (see Table 4). The ASD group reported higher levels of stress than the comparison group. These results were compared with the values reported by Abidin (1995), and the percentiles found in the ASD group were located at around 70 to 75, with the exception of two variables: depression (percentile 40) and attachment (percentile 60). In the comparison group, the percentiles were located around 50 on the competence, isolation, attachment, and health variables, while on the other variables (role restriction, depression, and spouse), they were located around 35, as in the case of the global index (see Table 4). The percentile for the Life Stress score was the same for both groups, and it was high (70).

Table 4.

Means, Standard Deviations, and F Values for PSI Parent Domain Subscales for ASD and Comparison Groups.

	ASD (n = 42)			Comparison (n = 42)
PSI	M	SD	Percentile	M	SD	Percentile	F(1, 82)	p	$η_{p}^{2}$
Competence	32.12	7.47	73	28.33	6.54	50	6.09	.016*	.069
Isolation	14.90	4.83	75	12.31	3.82	53	7.45	.008*	.083
Attachment	12.50	3.04	60	11.76	3.08	50	1.21	.273	.015
Health	13.64	3.98	75	11.07	2.89	50	11.47	.001*	.123
Role restriction	22.31	6.22	80	16.71	5.00	38	20.61	.000**	.201
Depression	18.00	5.22	40	16.83	4.91	30	1.11	.295	.013
Spouse	18.38	6.34	70	15.10	4.76	40	7.20	.009*	.081
Global index	131.86	27.83	70	112.12	22.19	35	12.91	.001*	.136
Life Stress	10.64	8.93	70	10.00	8.52	70	0.11	.737	.001

Note. PSI = Parenting Stress Index; ASD = autism spectrum disorders.

p < .05. **p < .001.

Parental Stress and Autism

To examine the relationship between the level of the children’s autism and their parents’ reports of stress, Pearson’s correlations were carried out between the PSI and the GARS-2 measures in the ASD group. The PSI distractibility/hyperactivity variable showed a statistically significant correlation with each of the three GARS-2 subscales (Stereotyped Behavior, r = .48, p = .001; Communication, r = .43, p = .004; and Social Interaction, r = .31, p = .045), as well as with the global AI (r = .47, p = .002). Furthermore, the PSI attachment variable showed a statistically significant correlation with the Communication subscale from the GARS-2 (r = .32, p = .035). Regression analyses showed that the global AI contributed significantly to the variance in predicting parental stress related to the child’s characteristics of Distractibility and Hyperactivity, R² = .22, F(1, 40) = 11.41, p = .002.

Parental Stress and the Child’s Verbal IQ

To examine the relationship between the child’s level of linguistic competence and the parents’ reports of stress, Pearson’s correlations were carried out between the PSI measures and the child’s verbal IQ in the two groups separately. Regarding the ASD group, all the PSI variables in the Child Domain—with the exception of the mood variable—showed a statistically significant correlation with the child’s verbal IQ (r = −.38, p = .012 for distractibility/hyperactivity; r = −.45, p = .003 for adaptability; r = −.43, p = .004 for reinforces parent; r = −.32, p = .037 for demandingness; r = −.49, p = .001 for acceptability; and r = −.49, p = .001 for the global index). This did not occur in any case in the Parent Domain. Regarding the comparison group, the PSI variables that correlated significantly with the child’s verbal IQ were adaptability (r = −.61, p = .000), acceptability (r = −.44, p = .003), the global index in the Child Domain (r = −.41, p = .006), and role restriction in the Parent Domain (r = −.34, p =.023). Separate regression analyses for each group were carried out. For both groups, the child’s verbal IQ contributed significantly to the variance in predicting parental stress in the Child Domain, R² = .20, F(1, 40) = 10.38, p = .003 for the ASD group, and R² = .17, F(1, 40) = 8.43, p = .006 for the comparison group.

Parental Stress and Child Performance IQ

To examine the relationship between the children’s level of intellectual ability and the parents’ reports of stress, Pearson’s correlations were performed between the PSI measures and the child’s performance IQ in the two groups separately. Regarding the ASD group, the PSI variables that correlated significantly with the child’s performance IQ were the global index in the Parent Domain (r = −.35, p = .022) and the spouse variable (r = −.32, p = .035), as well as the global index in the Child Domain (r = −.32, p = .039), the adaptability variable (r = −.36, p =.018) and the acceptability variable (r = −.33, p = .029). In the case of the comparison group, statistically significant correlations were also found with the same variables: adaptability (r = −.30, p = .049) and acceptability (r = −.31, p = .041). Separate regression analyses for each group were carried out. Only for the ASD group, the child’s performance IQ contributed significantly to the variance in predicting parental stress, both in the Child Domain, R² = .10, F(1, 40) = 4.55, p = .039, and the Parent Domain, R² = .12, F(1, 40) = 5.76, p = .021.

Parental Stress and Resilience

The mean value obtained on the resilience variable for the ASD group was 133.83 (SD = 16.7), which indicated moderate resilience. Pearson’s correlations were carried out between the PSI measures and the Resilience measure in the ASD group. The PSI variables that correlated significantly with the Resilience measure were the global index in the Parent Domain (r = −.43, p = .004), the competence variable (r = −.505, p = .001), and the depression variable (r = −.537, p = .000). Regression analyses showed that the Resilience measure contributed significantly to the variance in predicting parental stress related to competence, R² = .25, F(1, 40) = 13.68, p = .001; depression, R² = .29, F(1, 40) = 16.21, p = .000; and the global index, R² = .19, F(1, 40) = 9.34, p = .004, in the Parent Domain.

Finally, to study the contribution of each of the different variables within the entire model, two multiple regression analyses were performed for the ASD group: one for the PSI Parent Domain variable and the other for the PSI Child Domain variable, in which the following were introduced as independent variables: children’s performance IQ, children’s verbal IQ, children’s autism severity, and parents’ resilience. In addition, the prediction model for the PSI Parent Domain was statistically significant, F(4, 37) = 4.46; p = .005. The independent variables together predicted 32.5% of its total variance. Specifically, the following factors significantly contributed to the explained variance of this variable: resilience (β = −.443; t = −3.23; p = .003) and performance IQ (β = −.373; t = −2.30; p = .027). Moreover, the prediction model for the PSI Child Domain was also statistically significant, F(4, 37) = 3.91; p = .010. The independent variables together predicted 29.7% of its total variance. In this case, one factor significantly contributed to the explained variance of this variable: verbal IQ (β = −.471; t = −2.49; p = .017).

Discussion

In the present study, perceived parental stress was significantly higher in the ASD group than in the comparison group, which supports results from previous studies (e.g., Brobst et al., 2009; Hoffman et al., 2009; Lee et al., 2009). Moreover, the perceived parental stress in the ASD group was situated at much higher levels than the norms reported by Abidin (1995), especially in the case of stress related to the child’s characteristics, as in prior research (e.g., Rao & Beidel, 2009). Most of the variables in the PSI Child Domain were located at a percentile above 90, which is considered clinically significant. Some child behavioral factors, such as hyperactivity and demandingness, as well as the child’s difficulties with social skills and empathy, could be the basis for these elevated parental stress levels in the ASD group. Only the reinforces parent variable (the degree to which parents perceive their child as a source of gratification and positive reinforcement) was not statistically different between the two groups, and it was not high in any group (compared with the Abidin, 1995, norms). Hence, it seems that in no case was there a high perception of the child as a source of reinforcement.

On the contrary, although some previous studies (e.g., Rao & Beidel, 2009) did not find differences between the two groups of parents on perceived stress in the PSI Parent Domain, we found differences in most of the variables (in line with the study by Hoffman et al., 2009), except for the depression and attachment variables. Regarding the depression variable, the parents of the ASD group did not show greater feelings of discontent with themselves and their life circumstances or stronger feelings of sadness than the other parents. In the interview in which the PSI was filled in, some parents of the ASD group made comments such as “managing to be happy despite their circumstances,” “viewing their child’s peculiarities with a sense of humor,” or “having the necessary physical and psychic energy to fulfill their parental responsibilities.” Moreover, the parental stress related to depression was fairly low for both groups (compared with the Abidin, 1995, norms), in contrast to the study by Hoffman et al. (2009), which exclusively used mothers as the source of information (not fathers). In our case, although most participants were mothers (around 80%), some fathers also participated (about 20%), and this may partly explain the differences between the two studies.

Regarding the attachment variable, the reported level of closeness and emotional bonding with the child, as well as the self-perceived capacity to understand his or her feelings and needs, was similar in the two groups of parents, and it was around the mean (compared with the Abidin, 1995, norms). The same result was obtained in the study by Hoffman et al. (2009). In our study interview, some parents of the ASD group made statements such as “having great complicity with their child” or “knowing what is wrong with their child when he/she is angry or sad, in spite of his/her communicative limitations.” Hence, although parental stress in the ASD group was greater than that in the comparison group, this does not seem to be due to a different degree of closeness or affective and emotional bonding between parents and children. This finding supports, once again, the rejection of old ideas about blaming parents for their children’s handicap because of their apparently cold way of relating to them and the historical perspective of mothers of children with autism as “refrigerator mothers.” Likewise, parents may feel that their child is not responsible for his or her behavioral and functioning problems. When these types of causal attributions are made, one is more likely to help and show greater affective bonding. This type of attribution may serve to support parents’ understanding of their child’s feelings or needs and provide a sense of closeness. However, the stress related to life events was similar in both groups, and it was high (compared with the Abidin, 1995, norms). Stressful life events—such as divorce, separation, moving home, the death of a family member, economic, job, or legal problems—seemed to occur equally in both groups, and they produced comparable levels of stress. This result was also obtained by Rao and Beidel (2009).

The second objective of our study was to analyze the relationship between parental stress and several characteristics of the child. First, we found that the child’s autism symptom severity contributed significantly to predicting parental stress related to the child’s characteristics of distractibility and hyperactivity. In the interview in which the GARS-2 was filled in, some parents described their child with ASD as “very jittery and edgy” when they were asked about some items on the Behavior Stereotype subscale (e.g., “Makes rapid lunging, darting movements . . .” or “Prances”). In some cases, they perceived these behaviors as “extremely stressful.” It is likely that the child’s behavioral characteristics associated with ADHD (excessive reactions, nervousness, distraction, short attention span, etc.), which often have a comorbid presence in ASD (see, for example, Rao & Landa, 2013), constitute one of the main factors associated with parental stress. As noted above, data collected in our sample about the parents’ reports of their children’s inattention and hyperactivity/impulsivity revealed a significantly higher number of ADHD symptoms in the ASD group than in the comparison group (see the “Participants” section), which could partly justify the fact that parental stress related to ADHD behaviors has been significantly associated with the severity of the autism symptoms.

Second, the child’s verbal IQ was a significant predictor of parental stress in the Child Domain for both groups. The worse the child’s linguistic skill, the more the parental stress was related to the child’s characteristics. In the case of children with ASD, poor linguistic skills probably imply worse communication skills, which could be related to greater parental stress (Bebko et al., 1987). In the present study, the overall multiple regression model for predicting the PSI Child Domain variable showed that, in the ASD group, verbal IQ was the only factor that significantly contributed to the explained variance of this variable. Nevertheless, some studies (Davis & Carter, 2008; Hoffman et al., 2009) have found that autism-specific communication skills were not salient predictors of parental stress. In fact, in the present study, the child’s verbal IQ was not a significant predictor of parental stress in the Parent Domain in either group. There was no relationship between the child’s linguistic skills and parental stress related to the parents’ own characteristics and functioning as parents (regarding aspects such as spousal relations, health problems, social isolation, depression levels, etc.), even in the case of the children with ASD.

Third, the analysis of the relationship between parental stress and the child’s performance IQ yielded various interesting results in the case of the ASD group. Thus, the lower the child’s performance IQ, the more parental stress there was in the Parent Domain, especially stress related to the fit with the partner. Hence, the child’s lower intellectual ability was associated with higher parental stress related to worsening of the marital relationship due to a greater perception of lack of support in taking care of the child by the other partner and a more dysfunctional relationship between the couple. This result is in line with other studies that have associated the severity of the child’s disability with low levels of marital satisfaction and with the mothers’ perception of less support, respect, and commitment from their partners (Brobst et al., 2009). Moreover, the lower the child’s performance IQ, the greater the parental stress was in the Child Domain. In particular, the child’s lower intellectual ability was associated with higher parental stress related to the child’s capacity to adapt to changes and transitions and the degree to which the child meets the parents’ expectations and is accepted by them (although not consciously). Furthermore, the simple regression analyses showed that, only for the ASD group, the child’s performance IQ was a significant predictor of parental stress (in both the child and parent domains). This result contrasts with the study by Davis and Carter (2008), in which the cognitive functioning of children with ASD was not a salient predictor of parental stress, although in their study the sample consisted of young children, which may partly explain the differences between the two studies. However, in the present study the multiple regression models for predicting both variables of the PSI (PSI Parent Domain and PSI Child Domain) showed that performance IQ significantly contributed to the explained variance of the PSI Parent Domain, but not to that of the PSI Child Domain. This would indicate that the intellectual capacity of the child with ASD would be a significant predictor of the parental stress related to the parents’ own characteristics, but not of the parental stress related to the characteristics of the child.

The third objective of our study was to analyze the relationship between parental stress and the parental characteristic of resilience in the ASD group. The parents of the children with ASD perceived themselves as moderately resilient to adversity. Nonetheless, some comments collected in the interview in which the RS was filled in suggest good resilience levels, at least in some parents of the ASD group. Thus, they claimed that “their life makes more sense now than before having their child,” “they had learned a lot from their child,” “their child had helped them to be better people, to have the necessary energy to act, to overcome difficult situations, to solve problems . . . ” These comments suggest that, despite the challenges faced by families of children with ASD, some of them show adaptive management and even a positive contribution to the family dynamics. In the present study, the overall multiple regression model for predicting the PSI Parent Domain variable showed that the factor with the greatest weight was resilience. Furthermore, as the results of the simple regression analyses showed, the resilience measure was a significant predictor of parental stress in the Parent Domain, as well as two variables in this domain: depression and competence. Parents who perceived themselves as more resilient to adversity reported less stress associated with depressive symptoms and with their feelings of competence about their role as parents. This result is quite consistent with the research that has emerged recently about “learning how to be resilient” (see the literature review by Bekhet et al., 2012). In this review, indicators of resilience in family members of children with ASD included two factors related to depression and competence, respectively, optimism and self-efficacy. This could explain the significant relationship found in our study between resilience and parental stress related to these two factors (depression and competence). Indicators of resilience, such as optimism and self-efficacy, are predictors of a greater ability to cope with the challenge of raising a child with ASD.

Limitations

Our study presents some limitations. First, children with ASD with serious behavioral problems (i.e., aggressiveness) or very low cognitive functioning were not part of this sample, so the sample did not represent the entire autism spectrum. Second, some of the evaluation instruments we used (PSI, GARS-2, and RS) were self-report measures. Although these instruments have very good psychometric properties and high reliability and validity in the constructs they measure, they are subjective measures, which can lead to possible biases. Thus, for example, parents who are stressed for any reason can perceive their child’s behavior as more problematic. However, self-reports are crucial when assessing internalized states such as stress. The interviews that accompanied the completion of these questionnaires provided very useful and valuable comments made by parents that could hardly be obtained by other means. Nonetheless, the GARS-2 is not one of the most comprehensive autism measures. Third, in the case of the PSI, several of the subscales provide parent reports of children’s problem behaviors specifically associated with autism. Thus, Zaidman-Zait et al. (2010) found that parents of children with ASD endorsed items (from the Short-Form PSI) that reflected core ASD deficits, as they are associated with common behavioral features of ASD. Likewise, the GARS-2 only deals with autism-specific behaviors, so that incorporating a measure such as the Child Behavior Checklist would have allowed greater access to the childhood behaviors that parents find challenging. Nevertheless, in this article, we have presented data collected in our sample on the parents’ reports of their children’s inattention and hyperactivity/impulsivity (according to the DSM-IV-TR criteria), as well as their disruptive behavior. Fourth, in most cases the questionnaires were filled out by mothers, and only a small percentage were answered by fathers, which could limit the reach of the results and did not allow us to analyze possible differences between mothers’ and fathers’ reports. Fifth, this research used cross-sectional data, so that it did not study the variables over time. Sixth, this research did not include a comparison group with a different psychological disorder, so that we cannot definitively conclude that the group differences were unique to autism.

Conclusions and General Recommendations for Intervention

The study of parental stress is of great importance, given its implications in the quality of life of the entire family. The family continues to be the basic pillar of society in countries such as Spain; therefore, it is important to study the factors that are a source of family stress. Stress is a subjective process that stems from an incompatibility between stressors and resources, in which the parents’ appraisal plays a crucial role. As not all parents raising a child with ASD report high levels of stress, the study of factors associated not only with the child (such as behavior) but also with the parents (such as personality characteristics that promote resilient behavior) becomes important. The results found in the present study about parental stress in parents of children with ASD reinforce, once again, the benefits of providing these parents with the necessary resources (human, social, work, political, etc.) to allow them to deal effectively with stress, improve the family dynamics and functioning, and gain quality of life.

In this study, some of the child’s and parents’ characteristics associated with parental stress were investigated. Regarding the child’s characteristics, the severity of the child’s autism was a predictor of parental stress related to the child’s distractibility and hyperactivity as reported by the parents. It seems important, therefore, to carry out interventions to prevent or mitigate these behaviors associated with ADHD, which often have a comorbid presence in ASD. The child’s linguistic skills were a predictor of parental stress related to the child’s characteristics. Hence, speech therapy for children with ASD should not only be directed toward pragmatic aspects (communicative and functional aspects of language) but also toward other aspects of language that are necessary for reaching good linguistic competences (e.g., morphological and syntactic aspects). The child’s intellectual abilities were a predictor of parental stress, but only in the case of the ASD group. Hence, it seems important to promote work on cognitive skills (cognitive stimulation) as a basic goal in interventions with children with ASD, especially those who present intellectual disabilities.

However, the analysis of parents’ characteristics showed that, in spite of the high stress levels they experienced, the parents of children with ASD adapt to their children’s needs with the necessary closeness to enable them to effectively respond to their children, coinciding with the Hoffman et al. (2009) study. Moreover, the stress related to parental depression was situated at clinically low levels. Hence, the parents did not succumb to adversities and setbacks in life, even though the stress produced by life events was clinically high. In the case of the parents of children with ASD, this pattern of resilience is, obviously, quite important in facing and dealing effectively with day-to-day life with a child with ASD. Furthermore, those parents of children with ASD who perceived themselves as more resilient to adversity reported two parental characteristics closely related to two indicators of resilience: optimism and self-efficacy. Thus, it seems important to design interventions to increase positive cognitions or cognitive appraisal, such as the one carried out by Okuno et al. (2011), in which the family learns how to be resilient. In conclusion, enhancing resilience among family members of children with autism may be beneficial to both the parents and the children.

Footnotes

Acknowledgements

The authors thank the families and the teachers for their participation in this research and the University of Valencia for providing the required financial resources.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the University of Valencia, Project Grant UV-INV-PRECOMP12-79702 and the Generalitat Valenciana Government (Spain), grant number GV/2014/066.

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