Parenting and family adjustment scales (PAFAS): validation of a brief parent-report measure for use with families who have a child with a developmental disability

Research in Developmental Disabilities 72 (2018) 140–151

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Parenting and family adjustment scales (PAFAS): validation of a brief parent-report measure for use with families who have a child with a developmental disability

MARK

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Trevor G. Mazzucchellia,b, Julie Hodgesb, , Robert T. Kanea, Kate Sofronoffc, Matthew R. Sandersb, Stewart Einfeldd, Bruce Tongee, Kylie M. Graye,f, MHYPEDD Project Team1 a

Child and Family Research Group, and Brain, Behaviour and Mental Health Research Group, School of Psychology and Speech Pathology, Western Australia, GPO Box U1987, Perth, Western Australia 6845, Australia b Parenting and Family Support Centre, School of Psychology, The University of Queensland, Brisbane, Queensland 4072, Australia c School of Psychology, Faculty of Health and Behavioural Sciences, The University of Queensland, Brisbane, Queensland, 4072, Australia d Brain and Mind Centre, The University of Sydney, Sydney, New South Wales 2050, Australia e Centre for Developmental Psychiatry and Psychology, Department of Psychiatry, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria 3168, Australia f Centre for Educational Development, Appraisal and Research (CEDAR), University of Warwick, Coventry, UK

AR TI CLE I NF O

AB S T R A CT

Number of reviews completed is 2

Background: Children with a developmental disability are three to four times more likely than their typically developing peers of developing significant emotional and behavioural problems. There is strong evidence to suggest that individual biological and psychological factors interact with family functioning to precipitate and perpetuate these problems. Aims: This study examined the psychometric properties of a brief measure, the Parent and Family Adjustment Scales (PAFAS) for use with parents of children with a developmental disability. Methods: A sample of 914 parents of children (M = 6.27 years) with a developmental disability participated in the study. Disabilities included Autism Spectrum Disorder and Intellectual Disability Results: A confirmatory factor analysis supported a 16-item, four factor model of PAFAS Parenting, and an 11-item, three factor model of PAFAS Family Adjustment. The Parenting Scale measures parental consistency, coercive practices, use of encouragement and the quality of parent-child relationship. The Family Adjustment Scale measures parental emotional adjustment and partner and family support in parenting. Conclusions: The current study indicated that the PAFAS demonstrates promise as a brief measure of multiple domains of family functioning important for families who have a child with a developmental disability.

Keywords: Parenting Disability Assessment Validation

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Corresponding author. E-mail addresses: [email protected] (T.G. Mazzucchelli), [email protected] (J. Hodges), [email protected] (R.T. Kane), [email protected] (K. Sofronoff), [email protected] (M.R. Sanders), [email protected] (S. Einfeld), [email protected] (B. Tonge), [email protected] (K.M. Gray). 1Mental Health of Young People with Developmental Disabilities (MHYPEDD) project team members are (in alphabetical order) Sheena Arora (University of Technology Sydney), Kristina Clarke (The University of Sydney), Stewart Einfeld (The University of Sydney), Kylie M. Gray (Monash University), Stephen Goodall (University of Technology Sydney), Julie Hodges (The University of Queensland), Sian Horstead (The University of Sydney), Trevor G. Mazzucchelli (Curtin University and The University of Queensland), Lauren Rice (The University of Sydney), Matthew R. Sanders (The University of Queensland), Martha Schoch (The University of Queensland), Kate Sofronoff (The University of Queensland), John Taffe (Monash University), Bruce Tonge (Monash University), and Rosalie Viney (University of Technology Sydney). https://doi.org/10.1016/j.ridd.2017.10.011 Received 24 May 2017; Received in revised form 6 October 2017; Accepted 11 October 2017 0891-4222/ © 2017 Elsevier Ltd. All rights reserved.

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What this paper adds Given that factors such as coercive parenting, emotional adjustment difficulties of carers and relationship conflict between caregivers have been implicated in the development and maintenance of the emotional and behaviour problems of children with developmental disabilities, it is essential that allied professionals have a means for the early identification of these modifiable risk factors. This study found that the Parenting and Family Adjustment Scales (PAFAS) demonstrated promise as a brief outcome measure for assessing change in risk factors associated with family functioning. Due to its brevity and ease of scoring, this measure has the potential to be used at a public health level or in individual or group parenting interventions for parents of children with a disability. 1. Introduction Children with a developmental disability are three to four times more likely than their typically developing peers of developing significant emotional and behavioural problems (Einfeld, Ellis, & Emerson, 2011). These problems have serious consequences. They can threaten the physical health of children (Borthwick-Duffy, 1994; Nissen & Haveman, 1997), restrict children’s access to recreational and educational programs (Parmenter, Einfeld, Tonge, & Dempster, 1998), lead to exclusion from community settings (Borthwick-Duffy, Eyman, & White, 1987; Hill & Bruininks, 1984), and reduce occupational opportunities in the post-school period (Anderson, Lakin, Hill, & Chen, 1992). Behaviour problems not only impact the child, but are also one of the main predictors of parental distress (Floyd & Gallagher, 1997; Mazzucchelli, 2016; Plant & Sanders, 2007), use of respite services (Chan & Sigafoos, 2001; Sloper, Knussen, Turner, & Cunningham, 1991), and parents relinquishing the care of their child (Nankervis, Rosewarne, & Vassos, 2011). 1.1. Risk factors for behavioural and emotional problems While individual biological and psychological factors may place children with a developmental disability at increased risk for developing behavioural and emotional problems, there is strong evidence to suggest that these factors interact with social and environmental factors to precipitate and perpetuate problem behaviour (Oliver, Demetriades, & Hall, 2002; Tonge & Einfeld, 2003). In particular, coercive parenting practices, emotional adjustment difficulties of carers, and relationship conflict between caregivers have been implicated in the development and maintenance of the emotional and behavioural problems of children with developmental disabilities (Chadwick, Kusel, & Cuddy, 2008; Hastings & Lloyd, 2007; Koskentausta et al., 2007). Indeed, studies indicate that children with developmental disabilities are more likely to be exposed to such risk factors than their non-disabled peers (Beck, Daley, Hastings, & Stevenson, 2004). For instance, there is evidence that maternal expressed emotion towards children with an intellectual disability is more negative than expressed emotion towards children without intellectual disability (Beck et al., 2004; Green & Baker, 2011). Ragaldo, Harvinder, Inkelas, Wissow, and Halfon (2004) found that parents of children at risk of developmental delay were more likely to report that they spanked their child than were parents whose child was not at risk of developmental delay. These children have also been found to be at greater risk of maltreatment (Stalker & McArthur, 2012). The impact of adverse parenting practices and family dysfunction on a range of outcomes is well illustrated by the Adverse Childhood Experiences Study (ACES; Gilbert et al., 2015). The ACES assessed the long-term relationship between childhood experiences, including abuse and household dysfunction with adult outcomes. Abuse, as measured by this study, included yelling, swearing, hitting or grabbing a child, while household dysfunction included living with a parent who had a mental and/or substance use disorder or witnessing a parent being treated violently. This study found that there was an 80% likelihood that a child exposed to one of these behaviours was also likely to be exposed to at least one other (Felitti et al., 1998). In the main, these behaviours represent modifiable risk factors and underline the importance of prevention and early intervention to address the problem, with child-rearing practices, parental adjustment, and family relationships the obvious foci of assessment and modification. To assist with interventions and the planning of services aimed at improving the parenting and social context of children with a disability, it is necessary to have an efficient means of identifying families who exhibit high levels of relevant risk factors such as dysfunctional parenting practices and parental maladjustment. In terms of parents’ personal adjustment, many studies have reported that mothers of children with developmental disabilities have higher levels of stress (Herring et al., 2006) and poorer psychological well-being than other mothers (Barlow, Cullen-Powell, & Cheshire, 2006; Eisenhower, Baker, & Blacher, 2005). Parents often experience grief when they learn that their child has a disability and the process of adapting to disability can be prolonged in nature (Eakes, Burke, & Hainsworth, 1998; Rentinck, Ketelaar, Jongmans, & Gorter, 2007). Significantly, a bidirectional relationship has been found between parenting stress and child behaviour problems: high parenting stress contributing to a worsening in child behaviour problems over time, and child behaviour problems exacerbating parental stress (Neece, Green, & Baker, 2012; Woodman et al., 2015). 1.2. Measuring family functioning in parents of children with developmental disabilities Developers of evidence-based parenting programs recommend the use of parent and teacher report outcome measures to assist with treatment planning and to monitor the effects of parenting interventions (e.g., Mazzucchelli & Sanders, 2011). Child outcome measures that have been employed in intervention studies for children with a developmental disability include the Child Adjustment and Parent Efficacy Scale—Developmental Disability (Mazzucchelli, Sanders, & Morawska, 2011, see Emser et al., 2016), the Developmental Behaviour Checklist (Einfeld & Tonge, 1995), the Eyberg Child Behavior Inventory (Eyberg & Pincus, 1999), and the 141

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Strengths and Difficulties Questionnaire (Goodman, 1997). These child outcome measures have demonstrated both reliability and validity with a disability population. However, in terms of other areas of family functioning, there is a marked absence of concise parent-report measures of parenting skills, parental emotional adjustment, and family relationships that have demonstrated reliability and validity for this population. Measures such as the Parenting Scale (Arnold, O’Leary, Wolff, & Acker, 1993) and the Alabama Parenting Questionnaire (Shelton, Frick, & Wootton, 1996), when used with other measures to comprehensively assess family functioning tend to be long, use different or confusing scoring formats, have high literacy demands, and typically do not explicitly measure the specific targets of the intervention introduced in parenting programs (Sanders, Morawska, Haslam, Filus, & Fletcher, 2014). Recently, Sanders et al. (2014) validated a brief 30-item measure, the Parent and Family Adjustment Scales (PAFAS), for assessing changes in parenting practices, parental adjustment, and family relationships, in parents of typically developing children. This work suggested that the PAFAS demonstrated promise as a quick and easy to administer tool for assessing multiple domains of family functioning in parents of young (2- to 12-year-old) children who are developing typically. This raises the question of whether this scale might be useful with parents of children with a developmental disability. Consequently, the aims of the present study were to assess (a) the factor structure of the PAFAS, (b) the validity and reliability of this inventory with parents of children with a developmental disability, and (c) the relationship between aspects of parenting and child behaviour. 2. Method 2.1. Participants Participants were 1097 parents and caregivers living in Queensland and Victoria, Australia, who responded to a community parent survey (My Say survey), of whom 914 were included in the confirmatory factor analysis. This end-user survey was designed to encourage participants to share their opinions and perspectives and to “have their say” about their experience of parenting a child with a disability. The majority of respondents who identified as the main caregiver of a child with a disability were mothers (92.2%), 23.5% indicating that they worked part time and 44.8% that they were not in paid employment. The age of the parent/caregivers ranged from 21 years to 68 years (M = 39.01; SD = 6.80). The mean age of children was 6.27 years (SD = 2.36) with the majority being boys (73.3%). Parents reported the type of their child’s disability, with 78% of children identified as being diagnosed with an autism spectrum disorder, 28.7% an intellectual disability or developmental delay, and 28.1% a language delay or disorder. The majority of children (87.2%) received their diagnosis from a paediatrician (see Table 1 for a summary of the demographic characteristics of the sample). 2.2. Procedure The My Say Survey (My Say) was conducted as part of the Mental Health of Young People with Developmental Disabilities Project, a National Health and Medical Research Council funded project aimed at providing families of children with a disability access to free evidence-based parenting programs. In order to tailor the roll-out of programs to the needs of participating families, the online My Say survey was conducted prior to the commencement of programs. Parents were recruited mostly by emails sent from organisations (33.3%) or through a Facebook link (20%). Parents completed the survey online, by phone interview, or were posted a hard copy. Participants were instructed to answer all questions in relation to only one child with a disability (if parents had two children with disabilities, they were instructed to answer questions in relation to the oldest child). 2.3. Measures 2.3.1. Demographic variables Demographic information including parent age, their work and marital status, and child age and disability type was collected (see Table 1) 2.3.1.1. Parenting and family adjustment scales. The PAFAS (Sanders et al., 2014) assesses parenting practices and parent and family adjustment. The authors originally suggested that the PAFAS was a 28-item Parenting Scale encompassing two domains including parenting practices (17 items) and parent-child relationship (11 items) and a 12-item family adjustment scale of three domains including parental emotional maladjustment (5 items), family relationships (4 items) and parental teamwork (3 items). A subsequent confirmatory factor analysis supported an 18-item, four-factor, model of PAFAS Parenting, and a 12-item, three factor, model of PAFAS Family Adjustment (Sanders et al., 2014). The PAFAS Parenting factors incorporated parental consistency (5 items), coercive parenting (5 items), positive encouragement (3 items), and parent-child relationship (5 items). The PAFAS Family Adjustment factors encompassed parental emotional adjustment (5 items), family relationships (4 items), and parental teamwork (3 items). Each item is rated on a 4-point scale from 0 (not true of me at all) to 3 (true of me very much). Some items are reverse scored. For each subscale of the PAFAS Parenting and PAFAS Family Adjustment, the items are summed to provide scale scores, with higher scores indicating higher levels of dysfunction. Psychometric evaluation of the PAFAS in families with typically developing children revealed that these scales had good internal consistency, as well as satisfactory construct and predictive validity (Sanders et al., 2014). 2.3.3. Child Adjustment and Parent Efficacy Scale—Developmental Disability. The CAPES-DD (Mazzucchelli, Sanders, & Morawska, 2011) was developed for use with children with a developmental disability. It consists of a 16-item Total Problems scale (with two 142

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Table 1 Participants’ Demographic Information (N = 914). % Relationship to child Mother—biological Father—biological Marital status Married Co-habitating/de-facto Divorced Single Current work status Employed full time Employed part-time Employed casually Full time student Unemployed (looking for work) Not in paid employment Gender of child Male Female Type of Disability (more than one may apply – total > 100%) ID or DD Asperger’s Autism Autism Spectrum Disorder Cerebral Palsy Hearing Impairment Down syndrome Epilepsy Neurological disability Physical disability Who made this diagnosis? Paediatrician Psychiatrist Psychologist Speech Pathologist Occupational Therapist Neurologist

92.7 3.7 70.5 9.2 10.3 8.6 14.1 23.5 7.9 3.4 5.4 44.8 73.2 26.7 75.6 19.5 24.7 33.8 5.5 4.0 4.9 7.1 6.8 4.9 87.2 6.7 33.9 32.1 18.4 6.6

subscales, a Behavioural Problems subscale and an Emotional Problems subscale, measuring children’s externalising and internalising behaviour problems respectively), an 8-item Prosocial Behaviour scale, and a 16-item Self-Efficacy scale that measures parent’s selfefficacy in managing specific child problem behaviours. Items on the Total Problem and Prosocial Behaviour scales are each rated on a 4-point scale. For the Self-Efficacy scale, respondents indicate on a 10-point scale their level of confidence when managing each of the child behaviour problems. The Total Problems, Prosocial Behaviour, and Self-Efficacy scales have been found to have good to excellent internal consistency (Cronbach’s alpha of 0.90, 0.82, and 0.94 respectively; Emser et al., 2016). The Total Problem scale, Behavioural Problems subscale, and Emotional Problems subscale correlate significantly (0.85, 0.85, 0.65) with the Total Behaviour Problem Score, Disruptive/Antisocial subscale, and Anxiety subscale of another widely used measure of behavioural and emotional problems in children with a developmental disability, the DBC (Einfeld & Tonge, 1995; Emser et al., 2016). 2.4. Analytical procedure 2.4.1. Sample size A minimum recommended sample size for confirmatory factor analysis is 200 cases (Kline, 2011). In addition, the results of recent simulation studies suggest that the recommended sample sizes for CFA are N ≥ 200 for theoretical models and N ≥ 300 for population models (Myers, Ahn, & Jin, 2011). Based on these guidelines the available sample of 914 cases was acceptable for testing psychometric properties of the PAFAS. More specifically, Kline has recommended at least 5 participants for each free parameter in the model. The most complex model tested in the current study includes two factors and 40 items yielding 83 free parameters indicating a minimum sample size of 820 participants. The current sample of 914 participants exceeds this minimum estimate. 2.5. Construct validity The construct validity of PAFAS was examined in two steps. First, we evaluated its factorial validity, followed by an evaluation of its convergent validity. Factorial validity was evaluated through confirmatory factor analysis using Mplus Version 7.0 (Muthén & Muthén, 2012). The Chi square (χ2) goodness-of-fit statistic, the comparative fit index (CFI), the root mean square error of 143

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approximation (RMSEA) with 90% confidence interval, and the standardised root mean square residual (SRMR) were used to evaluate model fit. For the model to have an acceptable fit: the CFI values should be > 0.95, although values above 0.90 are considered adequate (Hu & Bentler, 1999); the RMSEA values should be < 0.05, though values as high as 0.08 are also considered reasonable (Browne & Cudeck, 1992); and the SRMR values should be < 0.08 (Browne & Cudeck, 1992). Models were re-specified based on modification indices (MIs), and theoretical considerations (Kline, 2011). To assess the extent to which each newly specified model exhibits an improvement over its predecessor, we used the Akaike information criterion (AIC) and Bayesian information criterion (BIC) values to compare the non-nested models. Smaller values of AIC and BIC indicate better fit of the model (Brown, 2015; Schreiber et al., 2006). Convergent validity of PAFAS was evaluated by examining associations between parenting and family adjustment constructs as measured by PAFAS and child adjustment and parental efficacy constructs of CAPES-DD. Pearson product-moment correlations were calculated to assess associations between constructs. 2.6. Reliability Due to the limitations associated with Cronbach’s alpha coefficient when the assumptions of tau-equivalence and uncorrelated errors are violated (Cheng, Yuan, & Liu, 2012; Sijtsma, 2009; Yang & Green, 2009) we assessed the reliability of the PAFAS by calculating composite internal consistency (Hancock & Mueller, 2001). Composite internal consistency is computed from the standardised factor loadings and the error variances associated with the PAFAS items and is used to assess the reliability of the latent constructs (i.e., factors). Values above 0.70 are considered good indicators of internal consistency, however, values above 0.60 are also acceptable (Enders, 2010; Hancock & Mueller, 2001). 3. Results 3.1. Data screening The Mplus full information (FIML) procedure was applied to account for missing data. FIML allows all available information to be used in the analysis without deleting cases with missing values (Enders, 2001). FIML has been shown to outperform traditional approaches for handling missing data (Bentler, 2006; Graham, 2009). Many of the 40 PAFAS items showed significant skew or significant kurtosis. Since the PAFAS variables were both ordered, categorical (4-point Likert scale) and not normally distributed, we employed the robust maximum likelihood estimator MLR, which produces standard errors and fit indices that are robust in relation to non-normality of observations and the use of ordered categorical variables when there are at least four or more response categories (Beauducel & Herzberg, 2006; Dolan, 1994; Muthén & Kaplan, 1985). 3.2. Construct validity of the PAFAS 3.2.1. Factorial validity The evaluation of factorial validity started with testing the hypothesised 2-factor model of the PAFAS (28-Item Parenting Scale, 12-Item Family Adjustment; Model A). As Table 2 shows, the fit of this model to the data was poor. The next step of the analysis involved conducting separate CFAs on each of the two scales. 3.2.2. Factor structure of PAFAS parenting scale A 2-factor model of the 28-item Parenting Scale (17-item parenting practices, 11-item parent-child relationship Model B1) was then tested. As Table 2 shows, the overall fit of this model to the data was poor. We then tested a 4-factor model of the Parenting Scale (5-item Parental Consistency, 5-item Coercive Parenting, 3-item Positive Encouragement, 5-item Parent Child Relationship), both with (Model B3; replicating Model F3 of Sanders et al., 2014) and without (Model B2) correlating errors between Items 13 (“I give my child attention [e.g. a hug, wink, smile or kiss] when they behave well”) and 22 (“I enjoy giving my child hugs, kisses and cuddles”), and Items 6 (“I follow through with a planned consequence [e.g. take away a toy] when my child misbehaves”) and 16 (“I deal with my child’s misbehaviour in the same way all the time”). Table 2 shows that the correlated errors model fit the data marginally better, but neither model provided an adequate fit. Modification indices suggested dropping Item 6 (“I follow through with a planned consequence [e.g. take away a toy] when my child misbehaves”) of the Parental Consistency factor and Item 22 (“I enjoy giving my child hugs, kisses and cuddles”) of the Parent Child Relationship factor from the model. The revised 4-factor, 16-item model (4-item Parental Consistency, 5-item Coercive Parenting, 3-item Positive Encouragement, 4-item Parent Child Relationship; Model B4) provided an adequate fit for the data. Although Item 16 (“I deal with my child’s misbehaviour the same way all the time”) had a small factor loading (.17) on Parental Consistency, this item was retained as it has face validity and its inclusion increased the model’s goodness of fit from χ2(99) = 381.28 to χ2(98) = 367.15, which is a statistically significant increase (p < 0.001). A graphic illustration of Model B4 is presented in Fig. 1. 3.2.3. Factor structure of PAFAS family adjustment scale A 3-factor model of the 12-item Family Adjustment Scale (5-item Parental Adjustment, 3-item Parental Teamwork, 4-item Family Relationships; Model C1). As Table 2 shows, the overall fit of this model to the data was poor; however, fit was improved by 144

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correlating errors between items 36 (“Our family members fight or argue”) and 37 (“Our family members criticize of put each other down”) Model C2; replicating Model G1 of Sanders et al., 2014). Modification indices suggested dropping Item 36 (“Our family members fight or argue”) of the Family Relationships factor from the model. The revised 3-factor model (5-item Parental Adjustment, 3-item Family Relationships, 3-item Parental Teamwork; Model C3) provided an adequate fit for the data (Table 2, Model C3). A graphic illustration of this model is presented in Fig. 2. 3.3. Convergent validity Table 3 presents Pearson product-moment correlation coefficients for all the constructs measured by PAFAS and CAPES-DD. As expected, Coercive Parenting, Parental Adjustment, Family Relationships, and Parental Teamwork showed the strongest (medium sized; Cohen, 1992) positive relationships with child Behaviour Problems, Emotional Problems, and Total Problems, meaning that higher levels of coercive parenting, parental emotional adjustment difficulties, and dysfunctional family relationships were associated with higher levels of children’s problem behaviour. Parental Consistency, Coercive Parenting, Parental Adjustment problems, Family Relationships, and Parental Teamwork showed (medium sized) negative relationships with parental Self-efficacy as measured by CAPES-DD, meaning that higher levels of dysfunctional parenting, parental adjustment difficulties, and dysfunctional family relationships were associated with lower levels of parental self-efficacy. 3.4. Composite internal consistency As shown in Table 3, three of the four factors comprising the Parenting Scale demonstrated adequate to good composite internal consistency, Coercive Parenting (.75), Positive Encouragement (.69) and Parent-Child Relationship (.80), while Parental Consistency (.53) was marginally lower than expected (Enders, 2010; Hancock & Mueller, 2001). The composite internal consistency for the 16item Parenting Scale was 0.74. For the Family Adjustment Scale the composite internal consistency for each of the factors, Parental Adjustment (.82), Family Relationships (.79) and Parental Teamwork (.76) was good. The composite internal consistency for the 11item Family Adjustment Scale was 0.86, which is relatively high and reflects the strong correlations among the factors (r = 0.53 to 0.63). Table 2 Confirmatory Factor Analyses of the Factor Structure of PAFAS Parenting and PAFAS Family Adjustment Scales. Model

A PAFAS Initial 2-factors model (I1–I40; 28-item Parenting, 12-item Family Adjustment) Testing factors individually (jigsaw piecewise procedure) B Parenting Practices B1 2-factors (I1 − I28; 17-item PP, 11-item PCR) B2 4-factors (I3, I5, I6, I8-I10, I12-I17, I19, I20, I22, I24, I25, I28) (5-item PC, 5-item CP, 3-item PE, 5-item PCR) B3 4-factors (I3, I5, I6, I8-I10, I12-I17, I19, I20, I22, I24, I25, I28; 5-item PC, 5-item CP, 3-item PE, 5-item PCR; includes correlated errors between I13 and I22, and between I6 and I16) B4 4-factors (I3, I5, I8-I10, I12-I17, I19, I20, I24, I25, I28 [6 & 22 deleted]; 4-item PC, 5-item CP, 3-item PE, 4-item PCR) C Family Adjustment C1 3-factors (I29 − I40; 5-item PA, 3-item PT, 4-item FR) C2 3-factors (I29 − I40; 5-item PA, 4-item FR, 3-item PT; includes correlated errors between I36 and I37) C3 3-factors (I29 − I35, I37 − I40 [Item 36 deleted]; 5-item PA, 3-item FR, 3-item PT)

χ2

df

CFI

SRMR

RMSEA

RMSEA 90% CI

AIC

BIC

5962.39***

739

0.496

0.103

0.088

.086–.090

77165.76

77364.43

3209.58***

349

0.531

0.124

0.095

.092–.098

54077.30

54216.68

625.11***

129

0.856

0.067

0.065

.060–.070

31845.51

31943.90

536.95***

127

0.881

0.065

0.059

.054–.065

31752.51

31854.18

367.15***

98

0.908

0.056

0.055

.049–.061

28545.05

28633.59

476.66***

51

0.867

0.061

0.096

.088–.103

21677.71

21741.78

264.25***

50

0.933

0.050

0.068

.060–.077

21426.35

21492.02

230.63***

41

0.933

0.045

0.071

.062–.080

19720.53

19779.64

Note. AIC = Akaike information criterion; it is used to compare non-nested factor models, the smaller the value the better the model. BIC = Bayesian information criterion; it is also used to compare non-nested factor models, the smaller the value the better the model. CFI = comparative fit index, values > 0.95 indicate good fit. CP = Coercive Parenting. PA = Parental Adjustment. PAFAS = Parenting and Family Adjustment Scales. PC = Parental Consistency. PCR = Parent Child Relationship. PE = Positive Encouragement. PP = Parenting Practices. PT = Parental Teamwork. RMSEA = root mean square error of approximation, values < 0.05 (or a 90% CI that encompasses 0.05) indicates good fit. SRMR = standardised root mean square residual, values < 0.08 indicate good fit. *** p < 0.001.

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4. Discussion This study aimed to (a) confirm the factor structure of the PAFAS, and (b) assess the validity and reliability of this brief inventory for parents of children with developmental disabilities. Rigorous psychometric evaluation on a large sample of parents of children disabilities found that a 4-factor (16-item) model of the Parenting Scale and a 3-factor (11-item) model of the PAFAS Family Adjustment Scale best fit the data and that both scales demonstrated adequate reliability. This outcome is consistent with the (Sanders et al., 2014) evaluation of the PAFAS in a population of parents of typically developing children and is an important strength of the PAFAS; this instrument may be meaningfully administered and interpreted for both families of typically developing children and families who have a child with a developmental disability. Although the original evaluation of the PAFAS (Sanders et al., 2014) introduced correlated errors to improve the fit of the model, the

Fig. 1. 4-factor confirmatory factory analysis of the 16-item PAFAS Parenting with standardised estimates. Numbers according to item numbers in the final version of the PAFAS (Appendix B of Sanders et al., 2014).

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present study found that in the three instances where correlated errors were present, one of each of the item pairs was redundant and that the fit was improved by removing these items from the relevant subscales. Analyses indicated that on the Parenting Scale, “I deal with my child’s behaviour the same way all the time” (Parental Consistency subscale) and “I give my child attention (e.g. hug, wink, smile or kiss) when they behave well” (the Parent-Child Relationship subscale) were the items to be retained as part of the subscale scores. Similar to the Parenting Scale, the present study found that the PAFAS Family Adjustment Scale best fit the data by removing an item from the Family Relationships subscale, “Our family members criticize or put each other down” was retained while analyses specified that “Our family members fight or argue” was the item to be removed from the subscale. While the items in each pair convey a similar sentiment, there is sufficient difference to suggest retaining these items when using the PAFAS in a clinical setting. The composite internal consistency for each of the subscales on the Family Adjustment Scale (Parental Adjustment Family Relationships and Parental Teamwork) was good, indicating promise for the use of this scale with parents of children with disabilities. Each of the subscales on the Parenting Scale demonstrated adequate internal consistency, except the Parental Consistency subscale. While each of the items on this scale represent important aspects of consistency, parents who have not yet participated in a parenting program may not recognise their importance or act consistently across these scenarios (e.g., “I threaten something [e.g. turn off the TV] when my child misbehaves but I don’t follow through” and “I give my child what they want when they get angry or upset”). It would be interesting to investigate whether the internal consistency of this scale improves when completed by parents who have participated in an evidencebased parenting program. It is also possible that the reliability of this and the other subscales is limited by the relatively small number of items that comprise each (Fabrigar, Wegener, MacCallum, & Strahan, 1999; MacCallum, Widaman, Zhang, & Hong, 1999). Pearson product-moment correlation coefficients for the PAFAS Parenting Scale and the CAPES-DD provided evidence of convergent validity. In particular, higher levels of coercive parenting were associated with higher levels of perceived child behaviour problems. Analyses also found that relationships between the three subscales of the Family Adjustment Scale and child behaviour were in the expected direction. Better parental adjustment, family relationships and teamwork between parents were all associated with fewer behavioural and emotional problems and more prosocial behaviour. Findings of this study in a large sample of parents of children with disabilities demonstrate promise for this brief measure for assessing multiple areas of family functioning considered important in this population. The Parenting and Family Adjustment Scale (PAFAS), was found

Fig. 2. 3-factor confirmatory factory analysis of the 11-item PAFAS Family Adjustment with standardised estimates. Numbered according to item numbers in the final version of the PAFAS (Appendix B of Sanders et al., 2014).

147

148

*p < 0.05, **p < 0.01, *** p < 0.001.

Mean SD Composite internal consistency

1.07 0.53 0.53

1. PAFAS parenting Parental Consistency 2. PAFAS parenting Coercive Parenting 3. PAFAS parenting Positive Encouragement 4. PAFAS parenting Parent-Child Relationship 5. PAFAS family adjustment, Parental Adjustment 6. PAFAS family adjustment, Family Relationships 7. PAFAS family adjustment, Parental Teamwork 8. CAPES-DD, Behaviour Problems 9. CAPES-DD, Emotional Problems 10. CAPES-DD Total Problems 11. CAPES-DD Prosocial Behaviour 12. CAPES-DD, Self-Efficacy

Table 3 Pearson Correlations among PAFAS and CAPES-DD.

0.67 0.56 0.69

– 0.01 .27*** .32*** .23*** .30*** .40*** .22*** .36*** 0.05 −0.34***

– .34*** .11* .20*** .30*** .23*** .22*** .19*** .13** .20*** −0.11** −0.32*** 0.83 0.51 0.75

2

1

0.43 0.48 0.80

– .38*** 0.07 .12** 0.08 −0.06 −0.09* −0.09* −0.20*** −0.05

3

1.42 0.62 0.82

– .33*** .22*** .22*** .17*** .14** .16*** −0.27*** −0.27***

4

1.16 0.75 0.79

– .50*** .40*** .30*** .32*** .33*** −0.22*** −0.45***

5

0.93 0.65 0.76

– .50*** .25*** .25*** .28*** −0.16*** −0.25***

6

1.21 0.71 0.89

– .28*** .24*** .29*** −0.14** −0.24***

7

0.74 0.70 0.71

– .57*** .96*** −0.25*** −0.48***

8

1.12 0.64 0.90

– .73*** −0.17*** −0.41***

9

1.34 0.55 0.80

– −0.26*** −0.51***

10

– .31***

11

6.61 1.95 0.94

12

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to be both valid and reliable in a large sample of parents of children with a variety of disabilities. Confirmation of the factor structure in both a population of parents of typically developing and children with disabilities lends confidence to the factor structure of this scale and indicates the promise of the use of this scale with carers of children with a disability. Parenting a child with a disability presents additional challenges that can affect parents’ capacity to be consistent, their emotional adjustment, their relationship with their child and other family members. The PAFAS subscale scores (e.g., coercion, encouragement, parent-child relationship, parental adjustment, and family relationships) capture such information ensuring that the PAFAS has both practical and clinical utility for practitioners working with this population. These findings should be considered in light of some limitations. While a range of disabilities was represented, the current sample was mostly comprised of parents of children with ASD (78%), with other disabilities such as cerebral palsy (6%) and Down syndrome (5%) forming a minority of the sample. Autism spectrum disorder is associated with an increased risk of problem behaviour compared to other disabilities (Brereton, Tonge, & Einfeld, 2006; Tonge & Einfeld, 2003) and thus it is possible that the results of the present study might be different in a sample of parents of children with other types of disability who might report more prosocial behaviour and greater well-being. Further studies should be conducted targeting parents and carers of children with other types of disability to confirm that the factor structure, reliability and validity of this parenting measure is robust and to permit comparisons across disability groups. Similarly, since the majority of respondents in the present study (93%) were mothers, it is not possible to make conclusions regarding the reliability and validity of the scales for fathers or other carers. Future studies should make special efforts to engage fathers to determine whether the scale is equally reliable and valid with this important group. Finally, future research is needed to further explore the scale’s reliability and to determine test-retest reliability, interrater reliability, and sensitivity to change. 5. Summary Children with a developmental disability are more likely than their typically developing peers of developing significant emotional and behavioural problems. Social and environmental factors such as coercive parenting emotional adjustment difficulties of carers, and relationship conflict between caregivers have been implicated in the development and maintenance of the emotional and behaviour problems of children with developmental disabilities. In order to prevent such behavioural and emotional problems and their sequalae it is imperative that allied professionals have a means for the early identification of modifiable risk factors. This study found that the Parenting and Family Adjustment Scales (PAFAS) demonstrated promise as a brief outcome measure for assessing change in family functioning. Due to its brevity and ease of scoring, this measure has the potential to be used at a public health or individual level or in group parenting interventions. The results of the confirmatory factor analysis supported a four-factor 16-item structure of the PAFAS Parenting Scale and a three-factor 11-item structure of the Family Adjustment Scale. This is an important finding and implies that the instrument can be meaningfully administered and interpreted for both families of typically developing children and families who have a child with a developmental disability. The association of the PAFAS scales with child behaviour and emotional problems and parental self-efficacy indicated the scale’s convergent validity. The current study indicated that the PAFAS demonstrates promise as a brief measure of multiple domains of family functioning important in this population. Author contributions T.G.M., J.H., K.S., M.R.S., and M.S. conceived of the study; R.T.K., T.G.M., and J.H. curated and analysed the data; M.R.S., S.E., K.G., K.S., and B.T. acquired the funding; K.S., K.G., J.H., M.S., M.R.S., B.T., J.T., and T.G.M. conducted the research process; T.G.M., J.H., and R.T.K. wrote the manuscript; K.G., K.S., S.E., B.T., and M.S. reviewed and edited the manuscript. Conflict of interest The Parenting and Family Support Centre is partly funded by royalties stemming from published resources of the Triple P—Positive Parenting Program, which is developed and owned by The University of Queensland (UQ). Royalties from the program are also distributed to the Faculty of Health and Behavioural Sciences at UQ and contributory authors of Triple P programs. Triple P International (TPI) Pty Ltd is a private company licensed by Uniquest, Pty Ltd, a commercialization company of UQ, to publish and disseminate Triple P worldwide. J.H., T.G.M., M.R.S., M.S., K.S., are employees of, or hold honorary positions at, the University of Queensland. J.H., T.G.M., M.R.S., K.S., have received, receives, or may in the future receive royalties and/or consultancy fees from TPI. S.A., K.C., S.E., K.G., S.G., S.H., R.T.K., L.R., J.T., B.T., and R.V. have no conflicts to declare. Acknowledgements This study was supported by a grant from the Australian Government’s National Health and Medical Research Council (NHMRC Program Grant APP1016919) for the Mental Health of Young People with Developmental Disabilities (MHYPEDD) project. Appendix A. Parent and Family Adjustment Scales (PAFAS) Scoring Key for Parents of Children with a Disability All 30 items are rated from 0 to 3. Note that items 2, 3, 6, 8, 11, 14, 15, 16, 17, 18, 20, 22, 23, 24, 25, 28, and 30 must be reverse scored (i.e., 0 = 3, 1 = 2, 2 = 1, 3 = 0) before summing the Total Score for each subscale. PAFAS consists of two scales Parenting and Family Adjustment. PAFAS Parenting consists of four subscales and PAFAS Family Adjustment consists of 3 subscales which can be interpreted using the table below. Three items (3, 15, and 26) do not load on any subscale, but are included for their clinical utility. 149

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Scale

Items

PAFAS Parenting Parental consistency 1, 4, 11, 12 Coercive parenting 5, 7, 9, 10, 13 Positive encouragement 2, 6, 8 Parent-child relationship 14, 16, 17, 18 No factor 3, 15 PAFAS Family Adjustment Parental adjustment 19, 20, 21, 22, 23 Family relationships 24, 25, 27 Parental teamwork 28, 29, 30 No factor 26

Interpretation

Possible Range

Higher scores indicate lower levels of consistency Higher scores indicate more coercive parenting Higher scores indicate lower levels of positive encouragement Higher scores indicate worse parent-child relationship Does not form part of the subscale scores—included for clinical utility

0–12 0–15 0–9 0–12

Higher scores indicate worse parental adjustment 0–15 Higher scores indicate worse family relationships 0–9 Higher scores indicate worse parental teamwork 0–9 Does not form part of the subscale scores—included for clinical utility

Note. The Parenting and Family Adjustment Scale may be sourced from Appendix B of Sanders et al. (2014).

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