AUTISM is a developmental disorder characterized by deficits in social relating, communication impairments, and the presence of restricted interests and stereotyped behaviors (American Psychiatric Association, 2000). Symptoms are usually apparent by 30 months of age (Short & Schopler, 1988; Volkmar, Stier, & Cohen, 1985), and recent research has revealed that the diagnosis can be made accurately in children as young as 2 years (Cox et al., 1999; Lord, 1995; Stone et al., 1999). Early identification is now widely recognized as an integral part of the medical management and treatment of children with autism (American Academy of Pediatrics Committee on Children With Disabilities, 2001a; Committee on Educational Interventions for Children With Autism, 2001; Filipek et al., 2000). Identification of autism at young ages can allow for earlier participation in specialized intervention services, which may reduce the impact of early deficits on later functioning (Happe, 1994; Mundy & Crowson, 1997).
Although the average age of diagnosis appears to have decreased over the past 2 decades (Howlin & Moore, 1997; Smith, Chung, & Vostanis, 1994), many children still do not receive definitive diagnoses of autism until age 3½ to 4 or older (Howlin & Asgharian, 1999; Mandell, Listerud, Levy, & Pinto-Martin, 2002). Autism diagnoses are behaviorally based, and many early childhood professionals are unfamiliar with or inexperienced in recognizing the behavioral manifestations of autism in young children. Research focusing on the symptoms of autism in children as young as 18 to 24 months has demonstrated the diagnostic utility of social-communicative behaviors such as imitation, play, and joint attention (Baird et al., 2000; Baron-Cohen, Allen, & Gillberg, 1992; Baron-Cohen et al., 1996; Cox et al., 1999; Lord, 1995; Stone, Coonrod, & Ousley, 2000; Stone et al., 1999). However, because diagnoses are rarely made prior to this age, less is known about symptoms that may be present even earlier.
Prediagnostic behaviors in infants have been studied using retrospective methods such as analysis of home videotapes and parental report of early symptoms. Although these studies are not without methodological concerns—such as lack of control over (and comparability of) situations in which infants are filmed and uncertainty about the degree of accuracy of retrospective reports—these areas of research have provided much-needed insight into the possible earliest behavioral manifestations of autism. Findings from videotape studies indicate that by 12 months, infants who receive a later diagnosis of autism demonstrate deficits in social-communicative and attentional behaviors that include pointing to and showing objects, looking at others, smiling socially, using appropriate facial expressions, orienting to visual stimuli, orienting to their name, and sustaining attention (Adrien et al., 1993; Baranek, 1999; Osterling & Dawson, 1994; Osterling, Dawson, & Munson, 2002; Werner, Dawson, Osterling, & Dinno, 2000). Results from retrospective parental report studies indicate that during the first 2 years of life, children with autism may demonstrate more impairments in early motor and social communication behaviors compared to age-matched typically developing children (Ornitz, Guthrie, & Farley, 1977), and more social-communicative deficits, unusual sensory behaviors, atypical play behaviors, and behavioral problems than do children with other developmental disabilities (Dahlgren & Gillberg, 1989; Ohta, Nagai, Hara, & Sasaki, 1987; Vostanis et al., 1998; Wimpory, Hobson, Williams, & Nash, 2000).
These studies suggest that both “positive symptoms” (ie, the presence or increased frequency of developmentally atypical behaviors) and “negative symptoms” (ie, the absence or decreased frequency of developmentally typical behaviors) may be present very early in development. However, diagnostic research with young children indicates that negative symptoms related to deficits in early social-communicative behaviors, such as failure to smile socially, are more common and hold greater utility for early identification than do positive symptoms involving sensory-motor behaviors such as hand-flapping (Cox et al., 1999; Lord, 1995; Stone et al., 1999). Unfortunately, negative social-communicative symptoms can be quite subtle and difficult to detect for untrained observers.
Nonetheless, in most cases, it is the parents and not professionals who are the first to suspect developmental problems in their child (Smith et al., 1994), and parents have been found to be accurate reporters about their child's general development (Glascoe & Sandler, 1995). In contrast, clinicians may be more likely than parents to detect the more subtle social-communicative problems in young children with autism (Stone, Hoffman, Lewis, & Ousley, 1994). Findings from videotape studies suggest that social-communicative deficits are present in infants prior to the emergence of parental concerns (Adrien et al., 1992). Parents may be less aware of social-communicative deficits than other developmental problems because they become adept at using compensatory strategies to engage their infants socially (Adrien et al., 1992; Baranek, 1999). Thus social communication problems, though holding great diagnostic utility, may not be the earliest symptoms detected and reported by parents.
Only a handful of studies have asked parents of children with autism to retrospectively identify the areas of development that first caused them concern (De Giacomo & Fombonne, 1998; Siegel, Pliner, Eschler, & Elliott, 1988; Smith et al., 1994). In these studies, the vast majority of parents (72% to 98%) indicated that problems with language development were a primary concern. Far fewer parents reported concerns related to medical problems and motor milestones (26% to 34%), general behavior problems (26%), or ritualistic and stereotyped behaviors (5% to 15%). Report of concerns about social development varied widely across studies, ranging from 39% to 84%. On an average, parents reported first becoming concerned when their child was between 17 and 19 months of age, and first sought help or advice about their concerns when their child was between 21 and 25 months of age. The majority of parents first shared their concerns with their child's pediatrician or other health workers.
Understanding early parental concerns is important for early diagnosis and intervention. The expression of parental concerns may be a professional's first indicator that a child is experiencing developmental difficulties; therefore, parental input can be essential in identifying children in need of further screening or assessment (Dulcan et al., 1990; Glascoe, Altemeier, & MacLean, 1989). Additional research into early parental concerns for children with autism is needed to clarify several issues. First, little is known about the extent to which the first concerns of parents of children with autism differ from those of parents of children with other disabilities. For example, one might expect that concerns related to social development would be more common for parents of children with autism; however, previous studies have not included comparison groups (De Giacomo & Fombonne, 1998; Siegel et al., 1988; Smith et al., 1994). Second, most studies examining parental first concerns have included parents of children who had already received an autism diagnosis, which may have biased their recollection of early symptoms. Moreover, the common procedure of including parents of older children and adolescents in studies of first concerns may affect the accuracy of parents' recall (Siegel et al., 1988; Smith et al., 1994). Finally, diagnostic issues complicate the interpretation of these studies. For example, De Giacomo and Fombonne (1998) included samples of children diagnosed with a range of autism spectrum disorders, and Smith et al. (1994) obtained diagnosis via parental report. Diagnostic clarity is critical to studies of this type.
The primary purpose of the present study was to examine similarities and differences in parental report of early concerns about development in matched groups of 2-year-old children with and without autism. The secondary purpose was to assess the relation between first concerns and current child behaviors in the children with autism. Group differences in age of first concern, specific type of concerns, and current social and communicative behaviors were examined.
Participants were 44 children between the ages of 24 and 36 months. The sample comprised 22 children with diagnoses of autism and 22 children with diagnoses of developmental delay (DD) who were individually matched on chronological age and mental age (both within 4 months). All children were recruited between 1991 and 1995 from a regional diagnostic center where they received multidisciplinary evaluations that included diagnostic, cognitive, speech-language, and behavioral measures. Diagnostic teams consisted of a psychologist, a speech-language pathologist, and a developmental pediatrician.
Inclusion criteria for all children were (1) a diagnostic evaluation prior to age 3; (2) the availability of cognitive test scores; (3) the absence of identified metabolic or genetic disorders; and (4) the absence of severe sensory and motor impairments. A total of 71 children (47 diagnosed with autism and 24 diagnosed with DD) initially met eligibility criteria; however, only 22 pairs of children could be individually matched (47% of the children with autism and 92% of the children with DD). In general, the unmatched children with autism had lower mental ages than those who could be matched.
The group of children with autism had all received a clinical diagnosis from a licensed psychologist on the basis of criteria provided in Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (American Psychiatric Association, 1987) or Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (American Psychiatric Association, 1994); these criteria require the presence of social deficits, communication impairments, and restricted activities and interests. In addition, only children who obtained scores within the autistic range on the Childhood Autism Rating Scale (CARS; Schopler, Reichler, & Renner, 1988) were included in this group. None of the children in the DD group had an identified etiology for their delay, and none had a CARS score within the autistic range.
Demographic data for both groups are presented in Table 1. No significant differences were found across demographic dimensions, including chronological age, mental age, developmental quotient, race, gender, and maternal level of education. As expected, groups differed on the CARS total score, t (42) = 10.6, P < .001.
Measures and Procedures
Informed consent was obtained from parents prior to the administration of any research measures. Measures were administered on the day of the child's diagnostic evaluation, and were completed before parents had received the results of their child's evaluation. Thus, parents were not yet aware of their child's diagnosis when completing the measures. In most cases, biological mothers served as respondents (n = 40). Two respondents were biological fathers, one was a biological grandmother who was the child's primary caregiver, and for 1 child, both biological parents completed the measures.
Mental age was assessed using the Mental Scale from the Bayley Scales of Infant Development (Bayley, 1969, 1993) (n = 42) or the Merrill-Palmer Scale of Mental Tests (Stutsman, 1948) (n = 2). These measures were administered either by a licensed psychologist or by a clinical psychology graduate student under the direct supervision of a licensed psychologist. Mental age equivalents were used for matching the autistic and DD groups. Developmental quotients were used to describe the sample (see Table 1), and were derived using the following formula: (mental age/chronological age) × 100.
Childhood Autism Rating Scale
The CARS (Schopler et al., 1988) is a 15-item behavioral rating scale used to evaluate the severity of symptoms of autism. It was completed by a licensed clinical psychologist on the basis of behaviors observed during the evaluation. CARS scores range from 15 to 60, with higher scores reflecting greater symptom severity. Scores of 30 and above are considered to reflect symptomatology consistent with autism.
Early Concerns Questionnaire
Parental concerns were evaluated using the Early Concerns Questionnaire (ECQ), an open-ended, pencil and paper measure developed for the current study. The ECQ was designed to provide information about the age of their first concerns (ie, “How old was your child when you first thought there might be something unusual about his/her behavior or development?”); the nature of their first concerns (ie, “What did you think was unusual?”); the age at which they first sought help (ie, “How old was your child when you first tried to get professional help, or tried to find out what was wrong?”); and the nature of their current concerns (ie, “What do you see as the main problem now?”). Questions about types of concerns were coded according to categories in the Autism Diagnostic Interview-Revised (ADI-R; Lord, Rutter, & Le Couteur, 1994), using a procedure similar to that described by De Giacomo and Fombonne (1998). These categories included (1) delayed or deviant language development (eg, poor receptive or expressive language skills, nonresponsiveness to sounds); (2) medical problems or delay in developmental milestones other than language (eg, motor delays, general cognitive delays); (3) lack of social interest or abnormality in social or emotional responses (eg, poor eye contact, social disinterest/difficulty engaging, not wanting to be held); (4) behavior problems not specific to autism (eg, sleeping problems, inattention, aggressive behavior); and (5) autistic-type behaviors (eg, motor stereotypies, repetitive behaviors, unusual play with objects). A sixth category for coding unclear or missing responses was also used. Interrater reliability was evaluated by having parents' responses coded independently by 2 examiners blind to the children's diagnostic status and then calculating percentage agreement and Cohen's kappa for initial and current concerns in each of the 6 categories. Reliability was high, with agreement for each category ranging from 95% to 100%, and kappas ranging from 0.66 to 1.0, with all but one kappa value above 0.81. Disagreements were discussed and recoded according to consensus decision.
Social Behavior Checklist
Parental report of social behavior was assessed using the Social Behavior Checklist (SBC; Stone & Lemanek, 1992), a measure adapted from the Preschool Social Behavior Checklist (PSBC; Stone, Lemanek, Fishel, Fernandez, & Altemeier, 1990). The SBC is a 30-item parental report measure of child social behaviors that includes items related to sharing toys, demonstrating affection, and expressing interest in peer play. Social behaviors involving expressive language skills (eg, greeting others, having conversations) were not included on the SBC because of the well-documented language deficits of children with autism and a desire to minimize the confounding effect of language abilities on social behavior. Parents rate how true each statement is for their child on a 3-point scale (ie, not true = 0, sometimes true = 1, almost always true = 2), with total scores ranging from 0 to 60 and higher scores indicating more normative social behaviors. Previous research with the SBC revealed an alpha coefficient of .88 and 2-week test-retest reliability of 0.80 (Stone & Lemanek, 1992).
MacArthur Communicative Development Inventory
Expressive vocabulary and nonverbal communication skills were assessed using two scales on the MacArthur Communicative Development Inventory (MCDI; Fenson et al., 1991, 1993). Expressive vocabulary was measured using the Vocabulary Checklist, which consists of 396 words from several categories (eg, food, people, pronouns, action words). Parents are asked to indicate which words their child understands (receptive vocabulary) and which words their child understands and says (expressive vocabulary). Only the expressive vocabulary scores were used in the present study. Nonverbal communication skills were measured using the First Communicative Gestures subscale. On this 12-item subscale, parents indicate on a 3-point Likert-type scale how frequently their child uses specific communicative gestures, such as reaching to be picked up or nodding one's head “yes.” Raw score totals for the Vocabulary Checklist and First Communicative Gestures subscale were used in data analysis.
Age of first concern and seeking advice
T tests revealed no significant group differences for the mean age at which parents first became concerned about their child's behavior or development or for the mean age at which parents first sought professional help or advice for their child. The mean age of first concern was 17.8 months (range = 6–30 months) for the children with autism and 16.6 months (range = 5–30 months) for the children with DD, P = .46. In both groups, 82% of parents became concerned before their child reached the age of 2 years. The mean age at which parents first sought professional help or advice for their child was 22.6 months (range = 9–35 months) for the children with autism and 23.2 months (range = 12–31 months) for the children with DD, P = .69. Likewise, the mean length of time between the child's age at parental first concern and the child's age at which parents first sought professional help did not differ between the groups; the mean length of time was 4.8 months (range = <1 month to 11 months) for the children with autism and 6.6 months (range = <1 month to 19 months) for the children with DD, P = .17.
First concerns and current concerns
Chi-square analyses indicated that the frequency with which specific developmental concerns were reported by parents of children with autism and parents of children with DD did not differ for any developmental area (all Ps > .15). Percentages of parents reporting concerns in specific developmental areas are presented in Table 2. The most common first concern reported by both groups was delayed language development, with 86% of parents of children with autism and 73% of parents of children with DD reporting this concern. Language delays were also described as the most common current concern, with 91% of parents of children with autism and 77% of parents of children with DD reporting this concern. Both groups of parents mentioned their children's social-emotional development, medical or developmental problems, behavior problems, or autistic-like behaviors relatively infrequently as areas of first or current concern. The patterns of parental concerns, or frequencies of specific co-occurring concerns (eg, concerns about both language and social development), were also examined and did not differ between the groups (all Ps > .14). In addition, there were no significant group differences for total number of first concerns (autistic group mean = 1.32, SD = 0.57, range = 1–3; DD group mean = 1.23, SD = 0.43, range = 1–2), P > .55, or for the total number of current concerns (autistic group mean = 1.27, SD = 0.46, range = 1–2; DD group mean = 1.18, SD = 0.50, range = 1–2), P > .63.
Current social and communicative behaviors
Significant group differences were found on parental report measures of current social and communicative skills (see Table 3). Parents of children with autism reported more impaired social behaviors on the SBC than did parents of children with DD, t(42) = −3.5, P < .001. On the MCDI, children with autism were described as using fewer words, t(42) = −2.1, P < .05, and fewer communicative gestures, t(42) = −3.7, P < .001, than did children with DD.
To learn more about the relation between parental first concerns and symptom severity in children with autism, correlations were used to examine the relation between age of first concern and children's current developmental quotient, CARS score, SBC score, and scores from the Vocabulary Checklist and the First Communicative Gestures subscales from the MCDI. A significant relation was found between age of first concern and the CARS score, r = −0.42, P = .05, and SBC score, r = 0.45, P = .03, in that parents of children with more severe autism symptoms and weaker social skills first became concerned about their child at younger ages.
This study examined parental report of early concerns about development and current social and communicative behaviors for developmentally matched groups of children diagnosed with autism and with nonautistic DD. When asked open-ended questions, the first concern for the vast majority of parents in both groups was their child's language development, with concerns about social abnormalities, stereotypic behaviors, medical problems/DD, and general behavior problems reported much less frequently. These results suggest that the earliest concerns experienced by parents of children with autism are not necessarily specific to autism, in that they do not reflect the unique pattern of symptoms in social impairment, repetitive behavior, and communication that is characteristic of this disorder. The prominence of initial concerns about language among parents of children with autism is consistent with that of previous research (De Giacomo & Fombonne, 1998; Siegel et al., 1988; Smith et al., 1994). The relative infrequency of reported concerns regarding social development is consistent with one previous study (De Giacomo & Fombonne, 1998), but inconsistent with other studies in which the majority of parents of children with autism (approximately 60%–84%) reported early concerns in this area (Siegel et al., 1988; Smith et al., 1994). However, the latter studies relied on the reports of parents of older children who had already received a diagnosis of autism. It is possible that these parents' recollections were affected by their knowledge of their child's diagnosis and the greater length of time over which they were being asked to recall their initial concerns, and that abnormalities in social behaviors become more apparent to parents when their child is somewhat older.
When parents were asked about their current concerns about their children at the age of 2, using open-ended questions, similar results were obtained. For both groups, language delays again emerged as the predominant concern, with no group differences in the frequency of this concern, and relatively few concerns reported in other behavioral domains. However, when questionnaires were used to ask specific questions about children's current social-communicative development, the parents of children with autism reported significantly more deficits in social development, expressive vocabulary, and use of communicative gestures. Thus, similar high rates of language concerns in the two groups belied considerable differences in actual vocabulary levels and communicative competence between the children with and without autism.
For the parents of children with autism, the results regarding their children's current social development were even more striking. Only 9% of parents of 2-year-olds with autism reported concerns about their child's social development when open-ended questions were used. However, their responses on the SBC, a questionnaire probing for specific social behaviors, revealed significantly more social impairments than those reported by parents of children with DD. Collectively, these results point to the potential benefit of using more specific and targeted questions in the early identification of autism, particularly after language concerns have been expressed.
There are several implications of these findings. Although research has demonstrated that social-communicative deficits, such as failure to imitate or engage in joint attention, are key indicators of autism in young children (Baird et al., 2000; Baron-Cohen et al., 1992, 1996; Cox et al., 1999; Lord, 1995; Stone et al., 1999, 2000), physicians and early childhood professionals should be aware that parents of children with autism may not spontaneously report early concerns in this area. Evidence from home video studies of infants later diagnosed with autism suggests that social deficits are present in infants prior to the emergence of parental concerns (Adrien et al., 1992). It is possible that parents of children with autism are less aware of, or less concerned about, social deficits because of the relative lack of knowledge about milestones for social development, especially compared with those available for language development. It is also possible that early social impairments are not detected by parents because of their accommodation to their child and their use of compensatory strategies to engage the child in social interactions (Adrien et al., 1992; Baranek, 1999).
The finding that parents of children with autism rarely reported concerns about their child's social development spontaneously, though they did report deficits in response to specific questions, also has significant implications for service providers. A parent's failure to report social concerns should not be interpreted as the absence of difficulties in this domain. On the contrary, it is extremely important for professionals to query about social behaviors more specifically, especially when language concerns are reported. Professionals can expect that a certain percentage of parents who have early concerns about their children's language development have children who will receive a later diagnosis of autism. Recent practice parameters prepared by the American Academy of Neurology (Filipek et al., 1999, 2000) and the American Academy of Pediatrics Committee on Children With Disabilities (2001b) provide examples of specific questions regarding social-communicative behaviors that can be used to determine whether a more in-depth autism evaluation is warranted. In addition, it behooves researchers in early identification to disseminate information about normative social-communicative behaviors, along with autism “red flags,” to community professionals as well as parents.
Consistent with previous research (De Giacomo & Fombonne, 1998; Siegel et al., 1988; Smith et al., 1994), parents of children with autism reported first becoming concerned about their child's development at about 17½ months and first seeking professional help at about 22½ months. These ages contrast sharply with the average age of diagnosis of autism, which is closer to 3½ to 4 years, if not older (Mandell et al., 2002; Stone & Rosenbaum, 1988). The successes of early intervention programs highlight the importance of closing this large gap between age of concern and age of diagnosis. The delay in diagnosis may result from a number of factors, such as reluctance to label young children or lack of familiarity with the early signs of autism. Additional research examining reasons underlying this delay is clearly warranted, so that interventions can be developed for overcoming obstacles to early identification. Our finding that parents of children with more severe symptoms of autism report concerns at earlier ages further supports the need for earlier recognition and intervention.
This study has some limitations that warrant mention. First, children in the autistic group were diagnosed clinically rather than by receiving standardized diagnostic testing. However, there is a precedent for using clinical diagnosis as the diagnostic “gold standard” for 2-year-old children (Volkmar et al., 1994). In addition, the diagnosis of autism was made by an experienced clinical psychologist (W. L. S.), and was supported by the CARS scores obtained for these children. Second, parents were asked to retrospectively identify their first concerns for their children. As with all retrospective research, the information provided by parents in hindsight may not be as accurate as the information that would be provided in a prospective study. However, for studies of its kind, this one has notable strengths, including the facts that the children were younger and the parents described their first concerns prior to receiving their child's diagnosis. These methodological features may have reduced parents' bias in recollecting early symptoms and increased the accuracy of their recall.
Finally, the generalizability of these findings to other samples of children with autism is not known. Only those parents who sought or had been referred for clinical evaluations at young ages (ie, 24–35 months) were included in this study. As a result, the extent to which the experiences of parents in this sample are representative of those in the larger population of young children with autism is not known. For example, the prominence of language concerns in this sample may have reflected referral patterns; it might be the case that language delays, relative to other types of concerns, are more likely to lead physicians and early childhood professionals to recommend developmental evaluations. It is not clear how the results may generalize to children whose parents first seek a clinical evaluation when the children are older, as may be the case with very high functioning children. In addition, as a result of the matching process, children included in the autism sample had higher mental ages than those who could not be matched. While this limitation is not unique to the present study, it may affect the generalization of these results to children with autism who are functioning at lower cognitive levels.
In sum, although parents of children with autism and nonautistic DDs report similar early concerns about their child's development when asked open-ended questions, these same parents can report differences in more subtle social-communicative behaviors when asked specific questions. Such questions may have more utility than open-ended questions in identifying young children who are at risk for an autism diagnosis. It is critical that early childhood professionals screen children for social-communicative deficits, even if parents fail to report specific concerns in this area, in order to maximize the likelihood that children with autism will obtain appropriately specialized early intervention services at the youngest age possible.
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