Young Adults With Developmental Coordination Disorder: A Longitudinal Study

Review of the Literature

DCD has been shown to have academic, social, behavioral, and emotional ramifications and a direct influence on quality of life for children and young adults (Cantell, Smyth, & Ahonen, 2003; Cermak et al., 2002; Kaplan, Dewey, Crawford, & Wilson, 2001; Miller et al., 2001; Missiuna & Polatajko, 1995; Rasmussen & Gillberg, 2000; Saban, Ornoy, Grotto, & Parush, 2012). Although DCD has garnered increased interest over the past decade (Cantell et al., 2003; Kirby, Edwards, & Sugden, 2011; Kirby, Edwards, Sugden, & Rosenblum, 2010), the focus has been primarily on the pediatric population, in which the prevalence is estimated at 6%–10% (APA, 2000; Dewey, 1995; Hamilton, 2002). Researchers have found that 30%–70% of children diagnosed with DCD in childhood maintain difficulties in daily functioning into young adulthood (Cousins & Smyth, 2003; Kirby, Sugden, Beveridge, & Edwards, 2008).

Cousins and Smyth (2003) assessed 19 people ages 18–65 yr who had been diagnosed in childhood with DCD and found that they continued be affected by DCD in adulthood, expressed as slowness, clumsiness, and avoidance of daily living tasks such as driving. In addition, participants described their motor coordination deficits as having a significant impact on their overall function, including reduced participation in daily tasks and poorer quality of life.

Kirby et al. (2008) investigated 93 students in higher education and found that those with DCD reported more motor and executive function difficulties than those without DCD. Kirby et al. (2010), comparing a group of 49 young adults (ages 17–42 yr) with DCD with a group of young adults without motor difficulties, found differences between the two groups. The young adults with DCD described more difficulty with writing quickly and neatly, being organized, and finding objects than the control group; in addition, the DCD group avoided attending dance clubs more often than the control group.

A growing body of evidence has addressed the symptoms and implications of DCD in adolescents and young adults (Cousins & Smyth, 2003; Kirby et al., 2010, 2011; Losse et al., 1991; Wagner et al., 2011), and findings imply that when DCD continues into adulthood, it may result in slowness; clumsiness; avoidance of daily living tasks; decreased quality of life; and reduced participation in a wide range of activities, such as maintaining gainful employment, being organized, and driving (Barnett, Henderson, Scheib, & Schulz, 2011; Kirby et al., 2008, 2010, 2011; de Oliveira & Wann, 2011). These difficulties appear to result from the gross motor, fine motor, handwriting, and time management deficits characteristic of this population (Cantell et al., 2003; Cermak et al., 2002; Cousins & Smyth, 2003; Kirby et al., 2008, 2010). It has been demonstrated that these participation difficulties are not context specific and affect the person in a wide range of environments, including home and educational settings (Cermak et al., 2002; Miller et al., 2001; Missiuna & Polatajko, 1995; Polatajko et al., 1995).

The period of adolescence and young adulthood, commonly referred to as a transition period, is a critical stage of development in which people learn how to participate independently in daily occupations, separate from their parents, and build a healthy perception of their independence (Hill, Brown, & Sorgardt, 2011; Kirby et al., 2010, 2011). Healthy development in this period promotes optimum participation and quality of life (Hill et al., 2011).

Beyond functional deficits, DCD can have emotional, behavioral, and social implications that can result in increased risk for mental health problems such as depression, anxiety, and obesity in adults (Cousins & Smyth, 2003; Hill et al., 2011; Mandich, Polatajko, & Rodger, 2003; Miyahara & Piek, 2006; Rasmussen & Gillberg, 2000; Skinner & Piek, 2001; Wagner et al., 2011). Adolescents and adults with DCD tend to have more negative emotions about themselves, reduced self-perception, decreased feelings of competency and self-esteem, and higher levels of anxiety and are less likely to attribute their successes to internal control than are young adults without DCD (Miyahara & Piek, 2006; Skinner & Piek, 2001; Tal-Saban et al., 2012). Furthermore, in a study comparing 20 young adults ages 18–27 yr with DCD with a group of 30 young adults without motor difficulties, Hill et al. (2011) found that the DCD group reported significantly lower life satisfaction and overall quality of life than the control group. Although research interest in this population is growing and more information is coming to light about the implications of DCD in older populations (Cantell & Kooistra, 2002), an urgent need remains for research exploring the quality of life and participation of young adults with motor deficits.

Study Background

Recently, we reported findings from a large-scale population-based study of randomly selected participants from the Israeli Army that investigated the effects of motor deficits on adolescents and young adults (Tal-Saban et al., 2012). In this initial study, which investigated the functional profile of young adults with DCD, we tested a large cohort (n = 2,379) of young adults using the Adolescents and Adults Coordination Questionnaire (AAC–Q; Tal-Saban et al., 2012). On the basis of results from this questionnaire, and following the recommendation of Geuze, Jongmans, Schoemaker, and Smits-Engelsman (2001), we established cutoff scores to identify participants with suspected DCD, probable DCD, and no DCD. Comparison between groups revealed differences for the functional measures assessed, thus validating the group placement of the participants and reinforcing the existence of the functional criteria of the DSM–IV–TR.

We considered the sample of 429 participants from the original study to be ideal for follow-up 3–4 yr after the initial study because the participants were still within the critical transition phase of development (Hill et al., 2011). The purpose of this longitudinal study was to examine the effects of DCD on participation, life satisfaction, and quality of life in young adults. This article presents the follow-up findings 3–4 yr after participants’ initial screening for DCD.

Method

Results

Participants had no known birth complications or psychiatric, physical, or neurological deficits. Normative cognition was implied by attendance in regular education frameworks. The homogeneity of the three study groups was assessed using χ² tests; no significant differences between groups were found for demographic and socioeconomic variables (including variables assessing current employment and living arrangements), with the exception of marital status; 24.4% of the control group, 3.3% of the borderline group, and 12.5% of the DCD group were married, χ²(2, N = 95) = 6.24, p = .04.

Twenty-five DCD participants (18% of the original sample; M age = 24.35 yr, SD = 0.88; 52% male), 30 borderline participants (20% of the original sample; M age = 24.48 yr, SD = 0.98; 43.3% male), and 41 control group participants (28% of the original sample; M age = 25.82, SD = 1.91; 48.8% male) agreed to participate. No differences by age, χ²(94, N = 95) = 97.28, p = .39, or gender, χ²(2, N = 95) = 0.43, p = .81, were found among these three groups.

To assess possible bias, we compared the participants who consented to participate in the follow-up study with participants from the original study who did not participate on measures of gender, years of education (at the time of the initial study), and whether they were granted testing accommodations for national exams (to accommodate learning disabilities). These comparisons were performed separately for each of the three study groups. No group differences were found for any measure with the exception of gender; the current study had more women in the DCD group, χ²(1, N = 174) = 5.27, p = .01.

MANOVA results indicated significant differences among the DCD, borderline, and control groups on total scores on the PEDAL and the Li–Sat 9 and the four domain subscores of the WHOQOL–BREF (Physical Health, Psychological Health, Social Relations, and Environment), F(7, 95) = 2.89, p = .001, η² = .17. Data from each questionnaire were then subjected to ANOVAs to determine between-group differences. Statistics for the individual scores are presented in Table 1. Comparisons revealed significant differences for the PEDAL and Li–Sat 9 scores and for the Physical Health, Psychological Health, and Environment domains of the WHOQOL–BREF; the only nonsignificant difference involved the Social Relations domain of the WHOQOL–BREF (Table 1).

Scheffé post hoc analyses revealed significant differences between the DCD and control groups for the PEDAL and Li–Sat 9 scores and for the Physical Health, Psychological Health, and Environment domains of the WHOQOL–BREF. Similarly, significant differences were found between the borderline and control groups for all questionnaire scores with the exception of the Environment subscore of the WHOQOL–BREF. No significant differences were found between the DCD and borderline groups for any questionnaire scores.

Findings regarding life satisfaction as reported on the Li–Sat 9 are presented in Table 2. The DCD and borderline groups reported lower life satisfaction than did the control group. Of the DCD group, 76.0% rated themselves as satisfied with life as a whole, compared with 89.3% of the borderline group and 97.5% of the control group. The DCD and borderline groups rated satisfaction with self-care and family life relatively higher and with vocational situation, financial situation, and partner relationship relatively lower.

Pearson correlation coefficients for scores on the three questionnaires yielded moderate to high correlations between scores (Table 3) and a high correlation between PEDAL, Li–Sat 9, and WHOQOL–BREF Psychological domain scores and between Li–Sat 9 and WHOQOL–BREF Social Relations domain scores. The moderately high negative correlation found between the PEDAL and the Li–Sat 9 and WHOQOL–BREF is attributable to the reverse scoring of the PEDAL, suggesting that the less the respondent participates in activities requiring planning and organization, the lower his or her perception of quality of life. A high positive correlation was found between Li–Sat 9 and WHOQOL–BREF Social Relations domain scores.

Linear regression was performed to determine which of the variables contributed to prediction of life satisfaction as measured by the Li–Sat 9 total score. The total score was used as the dependent variable and scores on the WHQOL–BREF and the PEDAL as the independent variables. Results indicate that for the total study sample, the Psychological Health domain of the WHOQOL–BREF (β = .442, p = .001) together with the PEDAL (β = −.265, p = .044) were significant predictors of life satisfaction. Because few group differences were found between the DCD and borderline groups, these two groups were combined for the follow-up regression analyses. For this combined group (n = 53), the Psychological Health domain of the WHOQOL–BREF remained a significant predictor of life satisfaction (B = .533, p = .001), but no measures were found to significantly predict life satisfaction for the control group.

Discussion

This study is the first of its kind to perform a 3–4-yr longitudinal follow-up of a sample of young adults who had previously been diagnosed with DCD and borderline DCD. In this study, we compared participation in daily life activities and quality of life in young adults with DCD, with borderline DCD, and without DCD. The findings expand the evidence that for children with DCD, various areas of functioning and participation continue to be affected into adulthood (Cantell et al., 2003; Cermak et al., 2002; Cousins & Smyth, 2003; Kirby et al., 2008, 2010).

The current results reinforce the claim that the significant difficulties of young adults with DCD may stem from reduced quality of life, as well as from reduced participation and independence in various activities of daily living (Hill et al., 2011; Kirby et al., 2010, 2011). On all of the instruments used in the study, both the DCD and borderline participants reported their quality of life and level of participation in daily activities to be lower than that reported by the control participants. Group differences between the control group and the DCD and borderline groups were clear, but no significant differences were found between the DCD and borderline groups, with the exception of the Social Relations domain of the WHOQOL–BREF. The relationship between motor coordination and function may not be not linear, as initially thought; once motor difficulties reach a certain level, they appear to exert a disproportionate influence on participation.

This finding is particularly interesting in light of the findings of the initial study (Tal-Saban et al., 2012), which found numerous group differences between the DCD and borderline groups. Several explanations are possible for this apparent disparity between the studies. Foremost, the initial study assessed participants on functional variables, whereas the current study assessed variables such as quality of life and participation, which may be perceived as more subjective and, therefore, more difficult to quantify. If so, the important factor in quality of life or life satisfaction may not be the intensity of the motor deficits or the effects of motor deficits on functional status, but rather the individual experience of these motor deficits. This hypothesis appears to be supported by the results of the linear regression, which revealed that the score on the Psychological Health domain of the WHOQOL–BREF was the most significant predictor of life satisfaction for the DCD and borderline groups but not for the control group.

Participation in occupations contributes to people’s health and quality of life and is instrumental in the development of skills and abilities, one way in which a person’s identity is molded (Baum & Christiansen, 2005). According to scores on the PEDAL, which assesses participation in daily activities that require planning and organization, the DCD and borderline groups participated less in such activities than the control group. A central area of optimal participation relates to activities of daily living; according to the DSM–5, one of the criteria for diagnosis of DCD is “poor performance in daily activities requiring motor coordination, with disturbances that interfere with academic achievement or activities of daily living” (American Psychiatric Association, 2013, Section 315.4 [F82]). The findings of this study provide support for this criterion even into young adulthood, consistent with other studies that assessed similar parameters within this population (de Oliveira & Wann, 2011; Kirby et al., 2010, 2011; Tal-Saban et al., 2012).

According to participants’ Li–Sat 9 total scores, the DCD and borderline groups rated their quality of life as lower than the control group and were less satisfied with their lives in general. Although no significant group differences were found between the DCD and borderline groups, it is worthwhile to look at scores on the individual items of the Li–Sat 9 (as recommended by the authors; Anke & Fugl-Meyer, 2003). Both groups consistently reported lower levels of satisfaction than the control group. Particularly noteworthy is the social contact score of the Li–Sat 9; 100% of the control group reported satisfaction, whereas 10%–20% of the DCD and borderline DCD groups reported dissatisfaction in this area. This finding differs from results on the WHOQOL–BREF, which reflected no group differences on the Social Relations domain. This difference may be explained by the possibility that for the Li–Sat 9, apparent differences in satisfaction did not reach statistical significance because we avoided individual comparisons of items to prevent excessive multiple analyses.

Despite this apparent trend in scores on the Li–Sat 9, the findings of no differences for the Social Relations domain of the WHOQOL–BREF are consistent with other studies in which participants showed some improvement in social skills at older ages, when social skills are less dependent on motor skills and participation in sports (Missiuna, Moll, King, Stewart, & McDonald, 2008). Studies with pediatric populations have shown that difficulties in social skills, accompanied by isolation, sadness, and lower self-esteem, are largely attributable to difficulties participating in the group sports activities characteristic of social interactions at younger ages (Jarus, Lourie-Gelberg, Engel-Yeger, & Bart, 2011; Poulsen, Ziviani, & Cuskelly, 2008). Missiuna et al. (2008) interviewed 9 young adults with DCD ages 19–26 yr who reported that their functional–social status had improved as they aged because they were no longer expected to participate in sports activities, made friends who accepted them despite their coordination deficits, and were able to select areas of study in which they had greater skills. This result may explain the findings in the current study of social abilities among people with motor deficits based on the WHOQOL–BREF.

With the exception of the social domains, the reported levels of satisfaction and dissatisfaction on the Li–Sat 9 appear to be consistent with those from the WHOQOL–BREF, which assesses aspects of quality of life from a much broader perspective. Differences were found between the DCD and borderline groups on one hand and control group on the other for all areas of the WHOQOL–BREF questionnaire (except for Social Relations), reinforcing the fact that quality of life and life satisfaction of people with motor deficits are negatively affected. The current findings support other research in this area that has reported lower self-perception, significantly lower life satisfaction, and reduced quality of life compared with control groups (Cousins & Smyth, 2003; Hill et al., 2011; Mandich et al., 2003; Miyahara & Piek, 2006; Skinner & Piek, 2001; Tal-Saban et al., 2012; Wagner et al., 2011). Further support for the connections among decreased life satisfaction, quality of life, and participation in people with motor deficits lies in the high negative correlations found between PEDAL scores (assessing participation in daily activities that require planning and organization) and scores on the questionnaires assessing quality of life and self-perception (Li–Sat 9 and WHOQOL–BREF), specifically the Psychological Health domain.

In summary, the findings of this longitudinal study of young adults diagnosed with DCD indicate that their functional deficits do not dissipate with age. Young adults with DCD continue to report decreased participation in various daily life activities, lending support to the DSM–5 criterion of significantly subpar performance in daily activities requiring motor coordination given the person’s chronologic age and measured intelligence. Moreover, the life satisfaction and quality of life of young adults with DCD is lower compared with those without motor difficulties.

Implications for Occupational Therapy Practice

This longitudinal research on young adults with DCD has the following implications for occupational therapy practice:

Study Limitations and Research Recommendations

The current study has several limitations. Foremost, the study used self-administered questionnaires, with no direct motor testing for diagnosis, and responses may be influenced by the participants’ state of mind at the time of completion. In addition, larger sample sizes would have enabled the performance of more in-depth statistical analyses to further describe the profile of this population.

Future research should aim at determining the factors that contribute to the wide range found in quality of life and participation within the groups. The same variables—participation, life satisfaction, and quality of life—should be tested with additional standardized assessments to see if the results are replicable. In addition, different elements of body functions, such as executive functioning and attention, should be tested to check if they are a fundamental part of DCD. A further area of exploration is the level of interest young adults diagnosed with DCD have in intervention and whether existing interventions for the pediatric population could be adapted effectively for the young adult population.