Skip to main content
NCBI home page
International Journal of Developmental Disabilities logoLink to International Journal of Developmental Disabilities
. 2021 Aug 20;69(2):317–326. doi: 10.1080/20473869.2021.1965826

A measurement of self-determination for people with intellectual disability: description of the AUTODDIS scale and evidences of reliability and external validity

Miguel Angel Verdugo 1, Eva Vicente 2,✉, Verónica Marina Guillén 3, Sergio Sánchez 4, Alba Ibáñez 3, Laura Elisabet Gómez 5
PMCID: PMC10071893  PMID: 37025337

Abstract

Background: Appropriate supports and instructional practices contribute to the development of self-determination. Also, research shows that the promotion of skills related to self-determination has been linked to the achievement of desired outcomes over the different life stages. Advances in self-determination require the development of assessment instruments because there is a reciprocal relationship between assessment and instruction. The purpose of this paper is to provide a description of the AUTODDIS Scale, along with evidence of its reliability and external validity.

Method: A sample of 541 people with intellectual disabilities aged from 11 to 40 was used to validate the scale.

Results: The reliability results indicate that the AUTODDIS Scale shows high internal consistency. The total score and subscale scores indicate moderate inter-rater reliability. The scores were also moderately to highly associated with other related measures of self-determination and quality of life (QoL).

Conclusion: Our results demonstrate that consistent and valid information can be obtained from the AUTODDIS Scale.

Keywords: self-determination, intellectual disability, young people, adults, assessment, reliability, validity

Introduction

Attempts to understand and operationalize the construct of self-determination at an international level date back many years (Abery and Stancliffe 2003a, 2003b, Field and Hoffman 1994, Wehmeyer 1999). The most recent theoretical framework for understanding self-determination is Causal Agency Theory (Shogren et al. 2015b). This model—developed from the functional model of self-determination (Wehmeyer 1999), as well as from more recent contributions from positive psychology and the socioecological conception of disability—understands self-determination as a dispositional characteristic that implies acting as the causal agent in one’s life.

Causal Agency Theory (Shogren et al. 2015b) describes three essential characteristics of self-determined actions (volitional action; agentic action; and action-control beliefs) and seven associated component constructs. Volitional action involves intentional and conscious decision-making based on personal preferences, and includes the component constructs of self-initiation and autonomy. Agentic actions imply adjusting one’s own actions by directing them toward the achievement of goals and overcoming obstacles as they occur, and comprise the component constructs of self-direction, self-regulation and pathways thinking. Finally, action-control beliefs refer to recognizing one’s own abilities and beliefs needed to reach goals, involving control-expectancies and acting with self-realization and empowerment.

This theory holds that these characteristics can be developed over the different life stages, particularly during adolescence, by providing the necessary supports and interventions to promote the component constructs (Shogren et al. 2020). Furthermore, there is a sufficient body of research linking the promotion of self-determination to the achievement of desired outcomes during the school years (Palmer et al. 2012, Shogren et al. 2012, Wehmeyer et al. 2011) and in the transition to adulthood (Martorell et al. 2008, Shogren et al. 2015c); as well as to enhanced quality of life (QoL) (McDougall et al. 2010, Lachapelle et al. 2005, Pascual-García et al. 2014, Wehmeyer and Schalock 2001).

In this context, implementing and evaluating the effectiveness of practices to promote self-determination requires appropriate tools (Shogren et al. 2018, Wehmeyer 2001) focused on both adolescence and adult life. Assessing self-determination is a complex process that should include a combination of standardized and informal procedures, incorporating information from multiple sources, involving the individuals concerned, their families, and professionals who know them well (Wehmeyer 2001). The persons with disabilities should be at the center of the process (Field et al. 1998) and the assessment itself should serve to enhance reflection, self-awareness, self-evaluation, and ultimately, self-determination. In other words, it should be based on an ‘empowerment evaluation’ (Fetterman 1996, Wehmeyer 2001).

Most of the instruments developed to date are self-reports designed for use by adolescents (Abery et al. 1995a, 1995b, Hoffman et al. 2015, Wehmeyer and Kelchner 1995, Wolman et al. 1994). The Arc’s Self-Determination Scale (Wehmeyer and Kelchner 1995) is one of the most internationally recognized and widely used scales for adolescents with intellectual disabilities. In Spain, this scale has been translated (Wehmeyer et al. 2006) and has also served as the basis for the development of another instrument that has demonstrated adequate psychometric properties (The ARC-INICO Scale; Verdugo et al. 2015a, 2015b). There have been recent initiatives to develop new tools that are aligned with the current theoretical model (Shogren et al. 2015b) and that enable the assessment of adolescents with and without disabilities. One such tool is the Self-Determination Inventory System (Shogren et al. 2015a, 2020), as well as its translation and adaptation into Spanish (Mumbardó-Adam et al. 2018b).

Despite the wide range of instruments available (albeit some already obsolete), in reality the vast majority are limited to the assessment of self-determination during the school years and are in self-report format. While there is no doubt about the importance of self-determination during these years, nor about the relevance of self-report measures as a way to place the person at the center of the assessment, an appropriate evaluation should use various methods and include professionals and relatives as a source of information, allowing the comparison of results (Field et al. 1998).

There is still a need to develop new assessment tools to address existing gaps. On the one hand, there is a lack of tools to assess self-determination in other age ranges beyond adolescence (i.e. from childhood through to early adulthood or even later). Many studies aimed at promoting self-determination in the adult people find it necessary to use other types of non-specific assessment instruments (e.g. quality of life scales: Martorell et al. 2008, Pascual-García et al. 2014) due to the lack of instruments for this stage. On the other hand, there is a need to standardize third-party assessment instruments, enhancing the range of tools available for comprehensive and comparable evaluations. Furthermore, given that self-report measures are not a suitable option for many people with disabilities (Shogren et al. 2020), scales based on information provided by others are a good alternative.

The AUTODDIS Scale (Verdugo et al. 2021) was developed in response to this need. A research project was carried out to develop and validate a new scale to assess the self-determination of people with intellectual disabilities aged 11 to 40 (using third-party information). The aim of the AUTODDIS Scale is not to diagnose or classify people with intellectual disabilities but to identify the strengths and weaknesses in self-determination focused on promoting interventions to improve their self-determination development and opportunities (i.e. an assessment to support planning; Schalock et al. 2010). Given the reciprocal relationship between assessment and instruction, valid and reliable measures of self-determination are needed to effectively evaluate the impact of interventions to promote self-determination (Shogren et al. 2018, Wehmeyer 2001).

The AUTODDIS Scale is a multidimensional self-determination instrument composed of different subscales to be completed by an external observer who knows the person with intellectual disability well (e.g. professionals or family members). The final version of the scale consists of 46 items—written in the third person—that assess six subdomains of self-determination according to the theoretical model proposed by Shogren et al. (2015b). The scale was developed over three stages, taking into account the steps proposed for the objective development of a test (Muñiz and Fonseca-Pedrero, 2019). First phase: scale elaboration and construction of the items. The first pool of items was developed using the results of a Delphi study, in which agreement was reached on a comprehensive pool of 115 items with adequate evidence of content validity based on consensus across stakeholders (Vicente et al. 2019b). Second phase: scale edition and pilot study. The wide pool of items was reduced to create the first field-test version of the scale, composed of 88 items and a pilot study was conducted to provide preliminary evidence of reliability and validity (Vicente et al. 2019a). Third phase: application and validation of the scale. This phase of development and validation of the scale involves several data analysis procedures, with the aim of guaranteeing the solidity of the final version. First, the scale was tested with a wide sample in order to provide evidence about the dimensional structure of a 46-item scale, distributed across six domains, through an Exploratory Structural Equation Modeling —ESEM— approach and measurement invariance across age and gender was established (Vicente et al. 2020c). Within this phase, the main goal of this paper is to provide evidences of reliability and external validity related to other variables that support and complete the validation of the AUTODDIS Scale.

Method

Participants

A total of 181 professionals acted as informants for the assessment of 541 people with intellectual disabilities between the ages of 11 and 40 years. Most professionals were women (75.1%); and their profiles were diverse: teachers (21%), carers (20.4%), psychologists (9.9%), occupational therapists (3.9%), directors of centers or services (2.8%), speech therapists (2.8%), social workers (2.8%), and educators (2.8%). Complementary information was also gathered from 106 family members, who acted as second respondents, which meant that 19.6% of the sample was double assessed. The majority were women (71.7%), and 56.6% of the total were the mothers of the participants with disabilities. The other assessors included fathers (22.6%), another family member (7.5% brothers/sisters; 3.8% aunts/uncles), and legal guardians or persons with another type of relationship (9.5%).

All informants had to meet some criteria to guarantee that they had enough knowledge of the assessed person to serve as their informant: (1) know them for at least four months (M = 64 months; SD = 57.15); and (2) have frequent contact (at least once a month) and opportunities to observe them in different situations nowadays (74.8% saw the assessed person daily or several times a week).

Regarding people with intellectual disability assessed (n = 541), most were men (n = 334; 61.7%); between the ages of 11 and 40 years (M = 26.28; SD = 8.28); and distribution by gender and age was not homogeneous (χ(30)2 = 47.23, p < .05).

In addition to filling in the AUTODDIS Scale, informants were asked to estimate participants’ level of intellectual disability, based not only on their intellectual functioning (classical perspective) but also on their adaptive behavior (current supports paradigm; Schalock et al. 2010, 2021). Most were identified as having a mild or moderate disability (Table 1). Further, when asked about associated conditions and possible specific etiologies, informants reported behavioral problems in 25.9% of participants (n = 140); communication difficulties in 18.1% (n = 98); mobility impairments in 16.3% (n = 88); epilepsy in 14% (n = 76); autism spectrum disorder in 8.7% (n = 47); cerebral palsy in 6.9% (n = 32); visual impairments in 3.7% (n = 20) and hearing impairments in 2.4% (n = 13). It should also be noted that for 12.2% of the sample (n = 66), the intellectual disability was associated with Down syndrome.

Table 1.

Participants with ID based on intellectual functioning and adaptive behavior.

Estimation based on intellectual functioning Estimation based on adaptive behavior
Mild Moderate Severe Profound Total no data
Mild 161 32 1 0 194  
Moderate 19 161 16 0 196  
Severe 0 12 56 2 70  
Profound 0 0 4 19 23  
Total 180 205 77 21 483 58
Open in a new tab

Instruments

Self-determination

The AUTODDIS Scale (Vicente et al. 2020c) is designed to assess the self-determination of adolescents and adults with intellectual disability between the ages of 11 and 40. This wide age range expands research regarding available scales for early adulthood—a critical transitional life stage during which self-determination is essential. Tests of configural, strong and strict invariance were executed between young people (11–21) and adults (21–40). Results have confirmed that the factor structure, factor loading magnitudes and item residual variances were equivalent between groups (see Vicente et al. 2020c). Different factorial models (i.e. correlational, hierarchical, bifactorial and exploratory structural equation models) were tested and good evidence of validity based on the internal structure were also showed in the same article. Previously, in the pilot study, the scale showed preliminary results indicating good reliability (with Cronbach’s alphas near or above .95; Vicente et al. 2019a).

The scale is composed of six subscales, which can be categorized into three domains of self-determination according to the most recent theoretical model (Shogren et al. 2015b). The first domain, volitional characteristics (autonomous and volitional actions), is made up of two subscales: autonomy (7 items) and self-initiation (6 items). The second domain, agentic characteristics (self-managed actions), includes the subscales of self-direction (12 items) and self-regulation (3 items). Finally, the action-control beliefs domain is structured around two subscales: self-realization (6 items) and empowerment (12 items). The response format for all items is a four-point Likert scale based on level of agreement (i.e. strongly disagree, disagree, agree, and strongly agree).

In order to provide evidence of convergent validity, prior to the administration of the AUTODDIS Scale, informants were asked via four items to estimate participants’ level of self-determination. The first was an item to estimate the global level of self-determination of the person being assessed. Informants were presented with five statements numbered 1 to 5 and were asked to choose the most appropriate (1 = The person has little or no control over his/her life, rarely acts as the causal agent in his/her life; 2 = The person has some control over his/her life, acts as the causal agent in some facets of his/her life; 3 = The person has moderate control over his/her life, acts as a causal agent in many facets of his/her life; 4 = The person has considerable control over his/her life, acts as the causal agent in most facets of his/her life; 5 = The person has total control over his/her life, acts as the causal agent in all facets of his/her life). For the three remaining items, informants were asked to estimate the person’s level in each of the three essential characteristics of self-determination (volitional action, agentic action, and action-control beliefs). They were provided with a description from the theoretical model (Shogren et al. 2015b) and asked to give an estimate for the person on a scale of 1 to 5 (where 1= low; 2 = moderately low; 3= medium; 4 = moderately high; 5 = high).

Quality of life

Informants were also asked to provide information on participants’ quality of life based on previously conducted assessments that were readily available at their centers. For that reason, a wide number of different scales were reported. They were asked to report standard scores for the quality of life domains along with the global quality of life index (i.e. total standardized score).

The INICO-FEAPS Scale (Gómez et al. 2014, Verdugo et al. 2013a) was the most frequently reported tool (n = 67 for the self-report version; and n = 94 for the report by others version); the San Martin Scale (Verdugo et al. 2014) was reported for 48 participants; the INTEGRAL Scale (Verdugo et al. 2010b) for 45 participants; the GENCAT Scale (Verdugo et al. 2010a) for 26; and the KidsLife Scale (Gómez et al. 2016) was reported for nine participants. All are scales with suitable evidences of reliability and validity in Spanish intellectual disabilities population.

The INICO-FEAPS Scale (as more reported scale) was therefore used to provide validity evidences based on the relationship of self-determination with other related constructs. Research endorses the relations between self-determination and quality of life (Lachapelle et al. 2005, McDougall et al. 2010, Wehmeyer and Schalock 2001, White et al. 2018). According to Wehmeyer and Schalock (2001) the theoretical frameworks of both “rely on or reference each construct as a means of defining the other” (p. 7). This scale includes a report by others version, comprising 72 items that provide a standard score for each of the domains according to the Schalock and Verdugo model (2002): social inclusion, rights, self-determination, emotional wellbeing, physical wellbeing, material wellbeing, personal development, and interpersonal relationships. A global index of quality of life is also provided. Data reported with this version were the most appropriate considering that third-party information is used, as the AUTODDIS scale.

Procedure

The sample was selected through the voluntary participation of 33 organizations that work with people with intellectual disabilities, covering most of the regions of Spain (11 of the country’s 17 autonomous communities). Previously, a thorough search of organizations was performed, and an email sent to all potential centers explaining the aims of this research and asking them to participate. The study was also disseminated through the Institute of Community Integration (INICO) website, social networks (e.g. Twitter and Facebook), and scientific conferences and meetings. Thus, some participating organizations showed interest in the project after receiving the informative email; and others contacted the research team directly after learning about the project through other means.

Each organization was responsible for identifying potential people to be assessed, then informing them and their families, and subsequently collecting the informed consents needed for the assessments. To satisfy the selection criteria, potential people had to: (a) have an intellectual disability and (b) be aged between 11 and 40 years. Similarly, the organizations were responsible for identifying from within their centers professionals who would act as informants, completing the assessment on each person’s behalf. They were also asked, as far as possible, to recruit relatives of the people with intellectual disabilities as second informants. Given that the AUTODDIS Scale is a third-party scale, selection criteria were established to be able to be selected as an informant. They should be completed by at least one informant (professional or relative) who: (a) knows the person well (minimum of 4 months), (b) have frequent contact with the person being assessed and (c) be familiar with the constructs of self-determination or commit to reading the scale instructions in which the concept and underlying theoretical model were defined.

The study received ethical approval from the Research Ethics Committee of the Community of Aragón (CEICA), and it complied with the principles for the development of research as set out in the Declaration of Helsinki. Participating organizations and the research team ensured that informed consents were collected for all participants, who voluntarily agreed to take part in the research. At no point did the study collect the names of the people being assessed; instead, identification codes were used to ensure confidentiality and anonymity.

Data analysis

The data were refined and processed with the statistics package SPSS 25.0. Cronbach’s αand McDonald’s ω were calculated to estimate the reliability of the scale in terms of internal consistency. The inter-rater reliability of the subscale scores and the total score of the AUTODDIS Scale was analyzed using the intra-class correlation coefficient (ICC) statistic and inter-rater correlations. The ICC was employed to examine the degree of agreement between evaluations provided by the two raters (professional and relative) on the same participant. The 95% confidence interval was calculated for each ICC and Spearman’s correlation to take sampling variation into account. Additionally, Chi squared (χ2) tests were carried out to contrast if there were significant differences amongst families and professionals’ perspectives on self-determination measurement. Evidences of external validity were obtained by relating the scores in the AUTODDIS Scale with other instruments that hypothetically measure the same construct and other related constructs (Elosua 2003), as detailed in instrument section. It was explored by comparing the self-determination estimation items and the INICO-FEAPS Scale scores to the results of the AUTODDIS Scale using Spearman’s correlations.

Results

Descriptive analysis

Table 2 shows the descriptive statistics and Spearman’s correlations among subscale scores. Although the values of the scores at the descriptive level showed a distribution far from normality, the Kolmogorov-Smirnov test was carried out, confirming that the scores were not normally distributed (p < .05).

Table 2.

Descriptive statistics and Spearman’s correlations.

  AUT SIN SDI SRE REA EMP VA AA AC
SIN .764                
SDI .726 .745              
SRE .618 .590 .725            
REA .639 .672 .741 .628          
EMP .639 .740 .824 .685 .748        
VA .958 .908 .772 .636 .684 .753      
AA .737 .742 .986 .816 .749 .833 .777    
AC .710 .755 .841 .701 .855 .979 .769 .850  
i 7 6 12 3 6 12 13 15 18
n 541 541 541 541 541 541 541 541 541
M 18.34 16.40 25.86 6.74 15.81 29.77 34.74 32.59 45.60
SD 5.56 4.29 8.34 2.06 3.69 8.45 9.39 10.01 11.61
Min 7 6 12 3 6 12 13 15 18
Max 28 24 48 12 24 48 52 60 72
Sk −.458 −.488 −.054 −.118 −.622 −.540 −.543 −.087 −.600
Ku −.460 .045 −.432 −.417 .747 −.168 −.118 −.361 .114
Open in a new tab

Note: AUT = autonomy score; SIN = self-initiation score; SDI = self-direction score; SRE = self-regulation score; REA = self-realization score; EMP = empowerment score; VA = Volitional Action Domain; AA = Agentic Action Domain; AC = Action-Control Beliefs Domain; i = number of items; n = sample; M = mean; SD = Standard Deviation; Min = minimum score; Max = maximum score; sk = skewness; ku = kurtosis.

Internal consistency

To estimate the reliability of the scale in terms of internal consistency, Cronbach’s α and McDonald’s ω were calculated for the data obtained by professionals (n = 541) and also for relatives (n = 106). Cronbach’s α is reported, as this has traditionally been the most widely used to assess the reliability of assessment instruments in social sciences. McDonald’s ω has also been included because it provides the greatest reliability estimate (Revelle and Zinbarg 2009). As Table 3 shows, all coefficients indicated excellent internal consistency in both applications, above .970 for the global scale, and ranging from .844 and .963 for the domains and subscales. All the subscales obtained good reliability indices, regardless of the informant, with the self-initiation subscale showing the highest level of internal consistency, and the self-regulation subscale the lowest.

Table 3.

Internal consistency of the AUTODDIS Scale.

  Cronbach’s α
 McDonald’s ω
 N items
Domains and Subscales PRO REL PRO REL  
Volitional Action Domain .946 .903 .947 .903 13
 AUT .916 .872 .917 .874 7
 SIN .903 .842 .906 .850 6
Agentic Action Domain .963 .956 963 .957 15
 SDI .961 .952 .962 .953 12
 SRE .841 .855 .844 .859 3
Action-Control Beliefs Domain .960 .945 .960 .946 18
 REA .909 .881 .909 .882 6
 EMP .949 .927 .950 .929 12
AUTODDIS Scale .982 .972 .983 .973 46
Open in a new tab

Note: AUT = autonomy; SIN = self-initiation; SDI = self-direction; SRE = self-regulation; REA = self-realization; EMP = empowerment; PRO = professionals; REL = relatives.

Inter-rater reliability

As mentioned, 106 participants had a double assessment, completed by different raters (i.e. a professional and a relative). The inter-rater reliability of the items, the domain and subscale scores, and the total score of the AUTODDIS Scale were analyzed through ICC and the inter-rater correlations. The results showed moderate item-to-item correlations ranging from .267 to .594 for all, except seven items. Table 4 presents the ICC and inter-rater correlations for domain and subscale scores, indicating medium-high convergence between the scores of professionals and relatives. The ICC for the total score was .832, indicating adequate inter-rater reliability. No significant differences were found amongst families and professionals measures.

Table 4.

Inter-rater reliability of the Scale and its domains and subscales.

  Rater 1 PRO M (SD) Rater 2 REL M (SD) χ2 p ICC 95% CI inter-rater rho 95% CI
AUT 19.49 (4.37) 19.01 (5.17) 0.03 .870 .707 .569 to .801 .543 .494 to .778
SIN 17.09 (3.42) 17.09 (3.42) 0 1 1.000   1.000  
SDI 27.19 (6,58) 26.51 (8.80) 0.38 .535 .710 .571 to .804 .601 .445 to .793
SRE 6.84 (1.73) 7.13 (2.21) 1.44 .230 .595 .404 to .725 .462 .289 to .618
REA 16.18 (2.78) 16.61 (3.50) 2.10 .148 .571 .368 to .708 .391 .193 to .565
EMP 31.24 (6.01) 30.29 (7.67) 1.91 .167 .808 .716 to .970 .597 .439 to .731
VA 36.55 (7.39) 36.18 (7.28) 0.04 .832 .892 .841 to .926 .747 .590 to .857
AA 34.04 (7.92) 33.73 (10.57) 0.05 .823 .712 .573 to .805 .612 .457 to .737
AC 47.42 (8.21) 46.92 (10.63) 0.38 .536 .771 .662 to .845 .566 .401 to .715
SD 118.01 (21.59) 116.52 (25.53) 0.23 .629 .832 .749 to .887 .653 .491 to .774
Open in a new tab

Note: AUT = autonomy; SIN = self-initiation; SDI = self-direction; SRE = self-regulation; REA = self-realization; EMP = empowerment; VA = Volitional Action Domain; AA = Agentic Action Domain; AC = Action-Control Beliefs Domain; SD = Self-determination total score; PRO = professionals; REL = relatives; M = mean; SD = Standard Deviation; ICC = intra-class correlation coefficient.

Relationship with conceptually related constructs

To evaluate validity in relation to other measures (i.e. self-determination estimation items and quality of life INICO-FEAPS Scale), Spearman’s correlation coefficients were calculated. The correlations support the relation of the self-determination estimation items with the AUTODDIS subscales. The estimation items were moderately to highly correlated to the subscale scores (from .600 to .766) and were always in the expected direction (Table 5).

Table 5.

Spearman’s correlations between AUTODDIS Scale and self-determination estimation items.

  AUT SIN SDI SRE REA EMP
Volitional action estimation .669 .756        
Agentic action estimation     .766 .600    
Action-control beliefs estimation         .645 .705
Global SD Estimation .677 .770 .745 .598 .631 .725
Open in a new tab

Note 1: AUT = autonomy; SIN = self-initiation; SDI = self-direction; SRE = self-regulation; REA = self-realization; EMP = empowerment; SD = self-determination.

Note 2: All correlations were significant at the .001 level.

The correlations also support the relationship among the INICO-FEAPS Scale and the AUTODDIS subscales. As shown in Table 6, the self-determination scores of the INICO-FEAPS Scale had high correlations with all the AUTODDIS subscale scores (from .412 to .637). Moderate correlations were also obtained among all the AUTODDIS subscales and the INICO-FEAPS scores in personal development and rights (from .305 to .488). The total score of the AUTODDIS Scale was closely associated with the self-determination score of the INICO-FEAPS Scale (rho= .556).

Table 6.

Spearman’s correlations between AUTODDIS Scale and INICO-FEAPS Scale.

  AUT SIN SDI SRE REA EMP
SD .551** .637** .500** .412** .430** .501**
RI .364** .381** .309* .347** .305* .358**
EW .144 .182 .099 .192 .180 .220*
SI .273* .346** .248* .200 .300* .398**
PD .434** .488** .373** .312* .345** .457**
IR .224* .269* .276* .149 .222* .240*
MW .286* .320** .252* .192 .177 .305*
PW −.093 .194 .104 .087 .157 .187
QOL .444** .514** .379** .344** 414** .476**
Open in a new tab

Note: AUT = autonomy; SIN = self-initiation; SDI = self-direction; SRE = self-regulation; REA = self-realization; EMP = empowerment; SD = self-determination; RI = rights; EW = emotional wellbeing; SI = social inclusion; PD = personal development; IR = interpersonal relations; MW = material wellbeing; PW = physical wellbeing; QOL = Quality of life Index.

*

p<.01.

**

p<.001.

Discussion

This article provides a description of the final version of the AUTODDIS Scale (its development process, purpose, structure, and administration), and in addition provides evidence to support its reliability and validity, building on previous findings obtained for the scale (Vicente et al. 2019a, 2019b, 2020c). Reliability results indicate that the AUTODDIS Scale and its subscales show high internal consistency. Similarly, the scores of the scale showed adequate inter-rater reliability (i.e. there was a relationship between the assessments completed by professionals and family members). Relations with other measures of self-determination and with related constructs such as quality of life (Lachapelle et al. 2005, McDougall et al. 2010, Wehmeyer and Schalock 2001, White et al. 2018) would support the AUTODDIS Scale as a means to assess self-determination and its essential components. Results show that there is a relationship between the global quality of life scale and all the AUTODDIS subscales, and also reveal high correlations between these subscales and the self-determination, rights, and personal development domains of the quality of life model (which are the most closely related domains); in contrast, they also indicate very low and non-significant correlations with the physical wellbeing domain. These results are in line with previous studies, which found an overall relationship between the concepts of self-determination and quality of life (Chao 2018, Wehmeyer and Schalock 2001, White et al. 2018), as well as evidence that the level of self-determination is a specific predictor of certain quality of life domains, such as personal development and personal fulfillment (McDougall et al. 2010).

In short, the AUTODDIS Scale can be regarded as a tool that provides reliable and valid information on the general level of self-determination and its component constructs (see Spanish version in https://sid-inico.usal.es/documentacion/escala-autoddis to download the final version of the scale). Using third-party information, it is a way to assess people with intellectual disability between the ages of 11 and 40 years in order to identify their needs or priorities for action with regard to self-determination. With sound psychometric properties, it is a useful scale for assessing self-determination at the micro, meso and macro levels. At the micro and meso levels, the information obtained can then be used to measure and enhance the impact of personalized support plans and implemented systems at the organizational level, thus further promoting self-determination (Shogren et al. 2018, Wehmeyer 2001). Similarly, at the macro level, it adds to the suite of specific instruments that foster scientific research, stimulating the design of evidence-based practices, since evaluation requires evidence (Schalock 2018). Along these lines, the current Quality of Life Supports Paradigm (Gómez et al. 2021, Verdugo et al. in press) provides a solid theoretical and professional framework for supports provision, person-centered evaluation of results, and to enhance organizations transformation and systems change. This new paradigm emphasizes the importance of providing supports within inclusive community settings and outcome-focused assessments; therefore, it is necessary to design and use specific and rigorous assessment tools, as the AUTODDIS scale, to guarantee personal support plans that improve all quality of life domains.

However, more extensive research and complex analyses (e.g. regression models) are needed to provide further evidence and to ensure the scale is effective for estimating the impact of practices aimed at promoting self-determination. Although professionals recognize the importance of the self-determination construct (Vaucher et al. 2019, Vicente et al. 2020a), there are still some barriers to its promotion (Mumbardó-Adam et al. 2020) and research should continue to develop new assessment and instructional tools and align professional practices with current theoretical framework. Also, specific studies are required to assess and promote self-determination of people with other disabilities or neurodevelopmental disorder (e.g. autism spectrum disorder) using specific instruments of self-determination (Morán et al. 2019), including assessment and promotion contextual opportunities for acting in a self-determined manner (Mumbardó-Adam et al. 2018a). Furthermore, when interpreting the results and implications of the scale, there are a number of limitations to consider. First, there are limitations related to the sample. The fact that a convenience sample was used makes it difficult to generalize the results, as does the fact that there was inadequate representation of the different levels of intellectual disability or of other developmental disabilities or associated conditions (e.g. autism spectrum disorder, cerebral palsy). It would therefore be helpful to increase the size and improve the representativeness of the sample to better demonstrate the reliability and validity of the scale in population subgroups that account for possible associated conditions; and also to include people without disabilities, as has been done with other self-determination assessment instruments (Mumbardó-Adam et al. 2018b, Shogren et al. 2020). It would also be necessary to expand the research considering control variables such as intellectual disability level or other external factors, as some studies, including one carried out by Vicente et al. (2020b), have showed that contextual opportunities have a mediator role in the classic relationship between ID level and self-determination. Similarly, not having two informants (professional and family member) for all our assessments constituted another sample-related limitation and more research would be needed considering a deeper analysis of their disprepacnies. Second, the lack of tradition in the use of self-determination scales did not allow us to use other self-determination results as comparators to analyze the external validity and we were enforced to use global quality of life measures as indicators. Besides, these evaluations were not consistent as the organizations had administered different quality of life scales and some of our assessed people did not even have anyquality of life data available. Finally, the scale was designed for third-party information. While this format is responding to a need, since there are no standardized tools of this kind, it nonetheless implies a limitation that should be resolved in future research, through the development of a parallel self-report version and the study of the relationship between this scale and other available self-report measures.

While further research is necessary, the results presented in this article together with the ones obtained in previous studies (Vicente et al. 2020c) suggest that the AUTODDIS Scale has considerable potential in the professional field as a guide for actions aimed at promoting self-determined behavior. There is no doubt that this instrument is responding to current demand for standardized self-determination assessment tools that are available in the Spanish language, that are aligned with the most recent theoretical concepts, and that widen the pool of available instruments to perform comprehensive assessments (Field et al. 1998, Verdugo et al. 2013b, Wehmeyer 2001). In other words, the AUTODDIS Scale expands the range of available tools that meet the following minimum requirements: (a) include standardized tools along side more informal instruments; (b) place the person at the center of the process; (c) gather information from different sources; and (d) incorporate the assessment into the intervention process, as the starting point for the promotion of self-awareness and reflection on the part of all stakeholders.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Funding Statement

This study was funded by Spanish Ministry of Economy and Competitiveness (R&D Projects, 2016) (PSI2016-75826-P. AEI/FEDER. UE).

Conflict of interest

No potential conflict of interest was reported by the authors.

References

  1. Abery, B. H. and Stancliffe, R.. 2003a. An ecological theory of self-determination: Theoretical foundations. In: Wehmeyer M. L., Abery B. H., Mithaug D. E. and Stancliffe R. J., eds. Theory in self-determination. Foundations for educational practice. Springfield, IL: Charles C. Thomas, pp. 25–42. [Google Scholar]
  2. Abery, B. H. and Stancliffe, R.. 2003b. A tripartite ecological theory of self-determination. In Wehmeyer M. L., Abery B. H., Mithaug D. E. and Stancliffe R. J. (Eds.), Theory in self-determination. Foundations for educational practice. Springfield, IL: Charles C. Thomas, pp. 43–78. [Google Scholar]
  3. Abery, B. H., Stancliffe, R. J., Smith, J., McGrew, K. and Eggebeen, A.. 1995a. Minnesota opportunities and exercise of self-determination scale - adult edition. Minneapolis: University of Minnesota, Institute on Community Integration. [Google Scholar]
  4. Abery, B. H., Stancliffe, R. J., Smith, J., McGrew, K. and Eggebeen, A.. 1995b. Minnesota self-determination skills, attitudes, and knowledge evaluation scale -adult edition. Minneapolis: University of Minnesota, Institute on Community Integration. [Google Scholar]
  5. Chao, P. C. 2018. Using self-determination of senior college students with disabilities to predict their quality of life one year after graduation. European Journal of Educational Research, 7, 1–8. [Google Scholar]
  6. Elosua, P. 2003. Sobre la validez de los tests. Psicothema, 15, 315–321. [Google Scholar]
  7. Fetterman, D. M. 1996. Empowerment evaluation: An introduction to theory and practice. In: Fetterman D. M., Kaftarian S. J. and Wandersman A. (Eds.), Empowerment evaluation: Knowledge and tools for self-assessment and accountability. Thousand Oaks, CA: Sage, pp. 3–46. [Google Scholar]
  8. Field, S. and Hoffman, A.. 1994. Development of a model for self-determination. Career Development for Exceptional Individuals, 17, 159–169. [Google Scholar]
  9. Field, S., Martin, J., Miller, R., Ward, M. and Wehmeyer, M.. 1998. A practical guide for teaching self-determination. Reston: Council for Exceptional Children, CEC Publications. [Google Scholar]
  10. Gómez, L. E., Alcedo, M. Á., Arias, B., Fontanil, Y., Arias, V. B., Monsalve, A. and Verdugo, M. Á.. 2016. A new scale for the measurement of quality of life in children with intellectual disability. Research in Developmental Disabilities, 53, 399–410. [DOI] [PubMed] [Google Scholar]
  11. Gómez, L. E., Schalock, R. L. and Verdugo, M. A.. 2021. A new paradigm in the field of intellectual and developmental disabilities: Characteristics and evaluation. Psicothema, 33, 28–35. [DOI] [PubMed] [Google Scholar]
  12. Gómez, L. E., Verdugo, M. A. and Arias, B.. 2014. Validity and reliability of the INICO-FEAPS scale: An assessment of quality of life for people with intellectual and developmental disabilities. Research in Intellectual and Developmental Disabilities, 36, 600–610. [DOI] [PubMed] [Google Scholar]
  13. Hoffman, A., Field, S. and Sawilowsky, S.. 2015. Self-determination assessment-internet (SDAi) User’s manual. Trinity, FL: Early Education Group. [Google Scholar]
  14. Lachapelle, Y., Wehmeyer, M., Haelewyck, M., Courbois, Y., Keith, K., Schalock, R. L., Verdugo, M. A. and Walsh, P. N.. 2005. The relationship between quality of life and self-determination: An international study. Journal of Intellectual Disability Research, 49, 740–744. [DOI] [PubMed] [Google Scholar]
  15. Martorell, A., Gutierrez-Recacha, P., Pereda, A. and Ayuso-Mateos, J. L.. 2008. Identification of personal factors that determine work outcome for adults with intellectual disability. Journal of Intellectual Disability Research, 52, 1091–1101. [DOI] [PubMed] [Google Scholar]
  16. McDougall, J., Evans, J. and Baldwin, P.. 2010. The importance of self-determination to perceived quality of life for youth and young adults with chronic conditions and disabilities. Remedial and Special Education, 31, 252–260. [Google Scholar]
  17. Morán, M., Gómez, L. E. and Alcedo, M.. 2019. Inclusión social y autodeterminación: Los retos en la calidad de vida de los jóvenes con autismo y discapacidad intelectual. Siglo Cero, 50, 29–46. [Google Scholar]
  18. Mumbardó-Adam, C., Guàrdia-Olmos, J. and Giné, C.. 2018a. Assessing self-determination in youth with and without disabilities: The Spanish version of the AIR self-determination scale. Psicothema, 30, 238–243. [DOI] [PubMed] [Google Scholar]
  19. Mumbardó-Adam, C., Guàrdia-Olmos, J., Giné, C., Shogren, K. A. and Vicente, E.. 2018b. Psychometric properties of the Spanish Version of the self-determination inventory student self-report: A structural equation modeling approach. American Journal on Intellectual and Developmental Disabilities, 123, 545–557. [DOI] [PubMed] [Google Scholar]
  20. Mumbardó-Adam, C., Vicente, E., Simó-Pinatella, D. and Coma, T.. 2020. Understanding practitioners’ needs in supporting self-determination in people with intellectual disability. Professional Psychology: Research and Practice, 51, 341–351. [Google Scholar]
  21. Muñiz, J. and Fonseca-Pedrero, E.. 2019. Diez pasos para la construcción de un test. Psicothema, 31, 7–16. [DOI] [PubMed] [Google Scholar]
  22. Palmer, S. B., Wehmeyer, M. L., Shogren, K., Williams-Diehm, K. and Soukup, J.. 2012. An evaluation of the Beyond High School model on the self-determination of students with intellectual disability. Career Development and Transition for Exceptional Individuals, 35, 76–84. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Pascual-García, D. M., Garrido-Fernández, M. and Antequera-Jurado, R.. 2014. Autodeterminación y calidad de vida: Un programa para la mejora de personas adultas con discapacidad intelectual. Psicología Educativa, 20, 33–38. [Google Scholar]
  24. Revelle, W. and Zinbarg, R. E.. 2009. Coefficients alpha, beta, omega, and the glb: Comments on Sijtsma. Psychometrika, 74, 145–154. [Google Scholar]
  25. Schalock, R. L. 2018. Seis ideas que están cambiando el campo de las discapacidades intelectuales y del desarrollo en todo el mundo. Siglo Cero, 49, 7–19. [Google Scholar]
  26. Schalock, R. L., Borthwick-Duffy, S. A., Bradley, V. J., Buntinx, W. H. E., Coulter, D., Craig, E. M., Gomez, S. C., Lachapelle, Y., Luckasson, R., Reeve, A., Shogren, K. A., Snell, M. E., Spreat, S., Tasse, M. J., Thompson, J. R., Verdugo, M. A., Wehmeyer, M. L. and Yeager, M. H.. 2010. Intellectual disability, definition, classification and systems of supports. 11th ed. Washington, DC: American Association on Intellectual and Developmental Disabilities. [Google Scholar]
  27. Schalock, R. L., Luckasson, R. and Tassé, M. J.. 2021. Intellectual disability. Definition, Diagnosis, Classification, and Systems of Supports. 12a ed. Washington, DC: American Association on Intellectual and Developmental Disabilities; [DOI] [PubMed] [Google Scholar]
  28. Schalock, R. L. and Verdugo, M. A.. 2002. Quality of life for human service practitioners. Washington, DC: American Association on Mental Retardation. [Google Scholar]
  29. Shogren, K. A., Little, T. D., Grandfield, E., Raley, S., Wehmeyer, M. L., Lang, K. M. and Shaw, L. A.. 2020. The Self-Determination Inventory–student report: Confirming the factor structure of a new measure. Assessment for Effective Intervention, 45, 110–120. [Google Scholar]
  30. Shogren, K. A., Palmer, S. B., Wehmeyer, M. L., Williams-Diehm, K. and Little, T. D.. 2012. Effect of intervention with the self-determined learning model of instruction on access and goal attainment. Remedial and Special Education, 33, 320–330. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Shogren, K. A., Shaw, L. A., Raley, S. K. and Wehmeyer, M. L.. 2018. Exploring the effect of disability, race-ethnicity, and socioeconomic status on scores on the self-determination inventory: student report. Exceptional Children, 85, 10–27. [Google Scholar]
  32. Shogren, K. A., Wehmeyer, M. L., Little, T. D., Forber-Pratt, A. J., Palmer, S. B. and Seo, H.. 2015a. Preliminary validity and reliability of scores on the Self-Determination Inventory-Student Report Version. Career for Development and Transition for Exceptional Individuals, 50, 251–263. [Google Scholar]
  33. Shogren, K. A., Wehmeyer, M. L., Palmer, S. B., Forber-Pratt, A. J., Little, T. J. and Lopez, S.. 2015b. Causal agency theory: Reconceptualizing a functional model of self- determination. Education and Training in Autism and Developmental Disabilities, 50, 251–263. [Google Scholar]
  34. Shogren, K. A., Wehmeyer, M. L., Palmer, S. B., Rifenbark, G. and Little, T.. 2015c. Relationships between self-determination and postschool outcomes for youth with disabilities. The Journal of Special Education, 48, 256–267. [Google Scholar]
  35. Vaucher, C., Cudré-Mauroux, A. and Piérart, G.. 2019. Perceptions and understandings of self-determination in the context of relationships between people with intellectual disabilities and social care professionals. International Journal of Developmental Disabilities, 67, 121–130. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Verdugo, M. A., Arias, B., Gómez, L. E. and Schalock, R. L.. 2010a. Development of an objective instrument to assess quality of life in social services: Reliability and validity in Spain. International Journal of Clinical and Health Psychology, 10, 105–123. [Google Scholar]
  37. Verdugo, M. A., Gómez, L. E., Arias, B., Navas, P. and Schalock, R. L.. 2014. Measuring quality of life in persons with intellectual and multiple disabilities: Validation of the San Martín Scale. Research in Developmental Disabilities, 35, 75–86. [DOI] [PubMed] [Google Scholar]
  38. Verdugo, M. A., Gómez, L. E., Arias, B., Santamaría, M., Clavero, D. and Tamarit, J.. 2013a. Evaluación de la calidad de vida en personas con discapacidad intelectual: La Escala INICO-FEAPS. Siglo Cero, 44, 6–20. [Google Scholar]
  39. Verdugo, M. A., Gómez, L. E., Arias, B. and Schalock, R. L.. 2010b. The Integral quality of life scale: Development, validation, and use. In: Kober R., eds. Enhancing the quality of life of people with intellectual disabilities. Dordrecht: Springer, pp. 47–60. [Google Scholar]
  40. Verdugo, M. A., Gómez-Vela, M., Fernández, R., Vicente, E., Wehmeyer, M., Badia, M., González-Gil, F., Calvo, M. I. and Guillén, V.M.. 2013b. ¿Cómo evaluar la autodeterminación? Escala ARC-INICO de Evaluación de la Autodeterminación. Siglo Cero, 44, 21–39. [Google Scholar]
  41. Verdugo, M. A., Schalock, R. L. and Gómez, L. E.. in press. El Modelo de Calidad de Vida y Apoyos: La unión tras veinticinco años de caminos paralelos. Siglo Cero. [Google Scholar]
  42. Verdugo, M. A., Vicente, E., Fernández-Pulido, R., Gómez-Vela, M., Wehmeyer, M. L. and Guillén, V. M.. 2015a. A psychometric evaluation of the ARC-INICO Self-Determination Scale for adolescents with intellectual disabilities. International Journal of Clinical and Health Psychology, 15, 149–159. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Verdugo, M. A., Vicente, E., Gómez-Vela, M., Fernández, R., Wehmeyer, M. L., Badia, M., González-Gil, F. and Calvo, M. I.. 2015b. Escala ARC-INICO de Evaluación de la Autodeterminación: Manual de aplicación y corrección. Salamanca: Publicaciones INICO [Google Scholar]
  44. Verdugo, M. A., Vicente, E., Guillén, V.M., Sánchez, S., Ibáñez, A., Fernández-Pulido, R., Gómez, L. E., Coma, T., Bravo-Álvarez, M. A. and Vived, E.. 2021. AUTODDIS: Evaluación de la Autodeterminación de jóvenes y adultos con discapacidad intelectual. Manual de aplicación y corrección. Salamanca: Publicaciones INICO [Google Scholar]
  45. Vicente, E., Coma, T., Mumbardó-Adam, C. and Simó-Pinatella, D.. 2020a. Self-determination and people with intellectual disability: A construct analysis from a professional perspective. International Journal of Disability, Development and Education, 1–15. doi: 10.1080/1034912X.2020.1735625 [DOI] [Google Scholar]
  46. Vicente, E., Guillén, V. M., Fernández-Pulido, R., Bravo, M. A. and Vived, E.. 2019a. Avanzando en la autodeterminación de jóvenes con discapacidad intelectual: Diseño de la Escala AUTODDIS. Aula Abierta, 48, 301–309. [Google Scholar]
  47. Vicente, E., Guillén, V. M., Gómez, L. E., Ibáñez, A. and Sánchez, S.. 2019b. What do stakeholders understand by self-determination? Consensus for its evaluation. Journal of Applied Research in Intellectual Disabilities, 32, 206–218. [DOI] [PubMed] [Google Scholar]
  48. Vicente, E., Mumbardó-Adam, C., Guillén, V. M., Coma-Roselló, T., Bravo-Álvarez, M.-Á. and Sánchez, S.. 2020b. Self-determination in people with intellectual disability: The mediating role of opportunities. International Journal of Environmental Research and Public Health, 17, 6201. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Vicente, E., Verdugo, M. A., Guillén, V. M., Martínez, A., Gómez, L. E. and Ibáñez, A.. 2020c. Advances in the assessment of self-determination: Internal structure of a scale for people with intellectual disabilities aged 11 to 40. Journal of Intellectual Disability Research, 64, 700–712. [DOI] [PubMed] [Google Scholar]
  50. Wehmeyer, M. L. 1999. A functional model of self-determination: Describing development and implementing instruction. Focus on Autism and Other Developmental Disabilities, 14, 53–61. [Google Scholar]
  51. Wehmeyer, M. L. 2001. Assessment in self-determination: Guiding instruction and transition planning. Assessment for Effective Intervention, 26, 41–49. [Google Scholar]
  52. Wehmeyer, M. L. and Kelchner, K.. 1995. The Arc's self-determination scale. Silver Springs, MD: The Arc of the United States. [Google Scholar]
  53. Wehmeyer, M. L., Palmer, S. B., Lee, Y., Williams-Diehm, K. and Shogren, K. A.. 2011. A randomized-trial evaluation of the effect of whose future is it anyway? On self-determination. Career Development for Exceptional Individuals, 34, 45–56. [Google Scholar]
  54. Wehmeyer, M. L., Peralta, F., Zulueta, A., González Torres, M. C. and Sobrino, A.. 2006. Escala de autodeterminación personal ARC Instrumento de valoración y guía de aplicación: Manual Técnico de la adaptación española. Madrid: Cepe [Google Scholar]
  55. Wehmeyer, M. L. and Schalock, R. L.. 2001. Self-determination and quality and life: Implications for special education services and supports. Focus on Exceptional Children, 33, 1–16. [Google Scholar]
  56. White, K., Flanagan, T. D. and Nadig, A.. 2018. Examining the relationship between self-determination and quality of life in young adults with autism spectrum disorder. Journal of Developmental and Physical Disabilities, 30, 735–754. [Google Scholar]
  57. Wolman, J. M., Campeau, P. L., DuBois, P. A., Mithaug, D. E. and Stolarski, V. S.. 1994. AIR self-determination scale and user guide. Palo Alto, CA: American Institutes for Research. [Google Scholar]

Articles from International Journal of Developmental Disabilities are provided here courtesy of The British Society of Developmental Disabilities

RESOURCES