Targeting Peer Contagion Dynamics in Children with ADHD: Effects from a Two-Site Randomized Controlled Trial.

OBJECTIVE: Parental Friendship Coaching (PFC) teaches parents to coach their children in friendship skills. This paper examines whether PFC fosters positive peer contagion processes (i.e. dyadic mutuality) and reduces negative peer contagion processes (i.e. coercive joining) within the friendships of children with attention-deficit/hyperactivity disorder (ADHD). METHOD: Participants were 134 families of children with ADHD and peer problems (age 6-11 years; 69% male; 72% white) at two Canadian sites, randomized to PFC or CARE (an active comparison intervention). Children were observed in the lab at baseline, post-treatment, and at 8-month follow-up during cooperation and competition tasks with a real-life friend. Amount and reciprocity of dyadic mutuality indicators (i.e. positive affect and positive behaviors) and coercive joining indicators (i.e. aggressive, controlling, and rule-breaking behaviors) between friends were coded. RESULTS: Across treatment conditions, children showed an increase in the amount of dyadic mutuality during cooperation and a decrease in the amount of coercive joining during competition over time. Relative to CARE, PFC induced a reduced amount of coercive joining behaviors during cooperation at post-treatment and follow-up. However, PFC led to decreases in the reciprocity of positive affect during cooperation at post-treatment and to increases in the reciprocity of coercive joining during competition at follow-up relative to CARE. Moderation analyses suggest PFC was associated with better outcomes for children with externalizing comorbidity, and for those with a stable or a best friend. CONCLUSIONS: Findings highlight the importance of transactional processes, contextual differences, externalizing comorbidities, and friendship status when assessing the efficacy of PFC.

KappaAcc: A program for assessing the adequacy of kappa.

Categorical cutpoints used to assess the adequacy of various statistics-like small, medium, and large for correlation coefficients of .10, .30, and .50 (Cohen, Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Lawrence Erlbaum Associates.)-are as useful as they are arbitrary, but not all statistics are suitable candidates for categorical cutpoints. One such is kappa, a statistic that gauges inter-observer agreement corrected for chance (Cohen Educational and Psychological Measurement, 20(1), 37-46, Cohen, Educational and Psychological Measurement 20:37-46, 1960). Depending on circumstances, a specific value of kappa may be judged adequate in one case but not in another. Thus, no one value of kappa can be regarded as universally acceptable and the question for investigators should be, are observers accurate enough, not is kappa big enough. A principled way to assess whether a specific value of kappa is adequate is to estimate observer accuracy-how accurate would simulated observers need to be to have generated a specific value of kappa obtained by actual observers, given specific circumstances. Estimating observer accuracy based on a kappa table the user provides is what KappaAcc, the program described here, does.

Peer contagion dynamics in the friendships of children with ADHD.

BACKGROUND: Friendships in middle childhood carry high developmental significance. The majority of children with attention-deficit/hyperactivity disorder (ADHD) have few friendships, unstable friendships, or poor relationship quality in any friendships they have. The current study used time-window sequential analysis to map the dynamics within the friendships of children with ADHD, specifically the peer contagion processes of dyadic mutuality and coercive joining. METHODS: Participants were 164 dyads consisting of a target child with ADHD and peer problems (age 6-11 years; 68% male; and 73% white) and a reciprocated friend. Dyads were observed in the lab during a cooperative task eliciting verbal negotiation processes to decide how to share a limited resource and during a fast-paced, engrossing, and competitive task. Both tasks were designed to mirror the real-world interactions of friends. Sequences of dyadic mutuality (i.e., reciprocity of positive affect and positive behaviors) and coercive joining (i.e., reciprocity of aggressive, controlling, and rule-breaking behaviors) between target children and friends were coded. RESULTS: Regarding dyadic mutuality, target children reciprocated their friends' positive affect in both tasks. They also reciprocated their friends' positive behaviors but only in the cooperative task. In contrast, they only reciprocated their friends' coercive joining behaviors in the competitive task. Medium to large reciprocity effects was found for 36%-53% (dyadic mutuality) and 38%-55% (coercive joining) of target children. CONCLUSIONS: These results extend findings of peer contagion processes to the friendships of children with ADHD and suggest that contagion may vary according to interaction context (i.e., competition vs. cooperation). Understanding the spread of peer contagion may illuminate how children with ADHD and their friends influence each other's adjustment over time and may guide friendship-focused psychosocial interventions for this population.

Using the Theory of Planned Behavior to Understand How Crisis Intervention Team (CIT) Training Facilitates Police Officers' Mental Health Referrals.

The Theory of Planned Behavior posits that behaviors are predicted by one's intention to perform them; intention is driven by attitude toward the behavior, subjective norm, and perceived behavioral control. We used this theory to predict Crisis Intervention Team (CIT)-trained and non-CIT officers' intention to facilitate referral of persons with suspected mental illnesses to mental health services. CIT-trained (n = 251) and non-CIT (n = 335) officers from six law enforcement agencies participated. CIT-trained officers had significantly greater scores on all constructs. Theory constructs fit the data well, and fit did not differ meaningfully between the two groups. Direct and indirect predictors together accounted for 28% and 21%, respectively, of variance in behavioral intention. Attitude was the strongest predictor. Intentions to facilitate mental health referrals may be driven by the same factors among CIT-trained and non-CIT officers, but CIT officers, even at a median of 22 months after training, have significantly higher scores on those factors.

Beyond talk: Contributions of quantity and quality of communication to language success across socioeconomic strata.

Infants from low-socioeconomic status (SES) households hear a projected 30 million fewer words than their higher-SES peers. In a recent study, Hirsh-Pasek et al. (Psychological Science, 2015; 26: 1071) found that in a low-income sample, fluency and connectedness in exchanges between caregivers and toddlers predicted child language a year later over and above quantity of talk (Hirsh-Pasek et al., Psychological Science, 2015; 26: 1071). Here, we expand upon this study by examining fluency and connectedness in two higher-SES samples. Using data from the NICHD Study of Early Child Care and Youth Development, we sampled 20 toddlers who had low, average, and high language outcomes at 36 months from each of 2 groups based on income-to-needs ratio (INR; middle and high) and applied new coding to the mother-toddler interaction at 24 months. In the high-INR group, the quality of mother-toddler interaction at 24 months accounted for more variability in language outcomes a year later than did quantity of talk, quality of talk, or sensitive parenting. These results could not be accounted for by child language ability at 24 months. These effects were not found in the middle-INR sample. Our findings suggest that when the quality of interaction, fluency and connectedness, predicts language outcomes, it is a robust relation, but it may not be universal.

The Quality of Mother-Toddler Communication Predicts Language and Early Literacy in Mexican-American Children from Low-Income Households.

This longitudinal study documents the key role of early joint engagement in the language and early literacy development of Mexican-American children from low-income households. This rapidly growing population often faces challenges as sequential Spanish-English language learners. Videos of 121 mothers and their 2.5-year-old children interacting in Spanish for 15 min were recorded in 2009-2011 in the Dallas-Fort Worth metropolitan area. Researchers reliably rated general dyadic features of joint engagement-symbol-infused joint engagement, shared routines and rituals, and fluency and connectedness-that have been found to facilitate language development in young English-speaking children. The construct respeto, a valued aspect of traditional Latino parenting, was also rated using two culturally specific items-the parent's calm authority and the child's affiliative obedience. In addition, three individual contributions-maternal sensitivity, quality of maternal language input, and quality of child language production-were assessed. General features of joint engagement at 2.5 years predicted expressive and receptive language at 3.6 years and receptive language and early literacy at 7.3 years, accounting for unique variance over and above individual contributions at 2.5 years, with some effects being stronger in girls than boys. The level of culturally specific joint engagement did not alter predictions made by general features of joint engagement. These findings highlight the importance of the quality of early communication for language and literacy success of Mexican-American children from low-income households and demonstrate that culturally specific aspects of early interactions can align well with general features of joint engagement.

Associations Between Two Domains of Social Adversity and Recovery Among Persons with Serious Mental Illnesses Being Treated in Community Mental Health Centers.

As mental health services are increasingly embracing the recovery model, we conducted a study to better understand how social adversity impacts recovery. We also examined how associations between social adversity and recovery are influenced (moderated or mediated) by symptom severity. Data on seven social adversity measures, eight recovery measures, and symptom severity were collected from 300 English-speaking participants, ages 18-65 years, with a diagnosis of a psychotic or mood disorder, from five community mental health agencies in diverse neighborhoods in Washington, D.C. We employed standard correlation, exploratory factor analyses, analysis of variance, and hierarchic regression procedures. Diagnostic category and gender impacted Home Environment Adversities (e.g., food insecurity, perceived neighborhood disorder), the diagnostic category-by-gender interaction influenced Social and Economic Adversities (e.g., years of education and income), and gender affected Recovery. Controlling for diagnostic category and gender, Social and Economic Adversities accounted for 1.7% of variance in Recovery, while Home Environment Adversities accounted for 8.6% (their joint influence was 3.4%). Although symptom severity did not moderate these associations, it partially mediated the effect of Social and Economic Adversities on Recovery, and substantially mediated the effect of Home Environment Adversities on Recovery. The extent to which patients with serious mental illnesses experience recovery may be meaningfully influenced not only by symptoms, but by their social and environmental circumstances.

An Expanded View of Joint Attention: Skill, Engagement, and Language in Typical Development and Autism.

This study provides an expanded view of joint attention and its relation to expressive language development. A total of 144 toddlers (40 typically developing, 58 with autism spectrum disorder [ASD], 46 with developmental delay [DD]) participated at 24 and 31 months. Toddlers who screened positive for ASD risk, especially those subsequently diagnosed with ASD, had poorer joint attention skills, joint engagement during parent-toddler interaction, and expressive language. Findings highlight the dynamic relation between joint attention and language development. In the ASD and DD groups, joint engagement predicted later expressive vocabulary, significantly more than predictions based on joint attention skills. Joint engagement was most severely impacted when toddlers did not talk initially and improved markedly if they subsequently began to speak.

Intervention focus moderates the association between initial receptive language and language outcomes for toddlers with developmental delay.

This ex-post facto study reanalyzed data from Romski et al. to examine whether intervention focus moderated the relationship between pre-intervention standardized measures of receptive language and post-intervention standardized measures of receptive and expressive language age and observations of expressive target vocabulary size. In all, 62 toddlers with developmental delay were randomly assigned to augmented communication-input (AC-I), augmented communication-output (AC-O), or spoken communication (SC) interventions. AC-I provided augmented language input via spoken language and a speech-generating device (SGD); AC-O encouraged the production of augmented output via an SGD; and SC provided spoken input and encouraged spoken output without using an SGD. Intervention focus moderated the impact of initial receptive language on expressive language age and expressive target vocabulary size. Participants in AC-I, when compared to those in the other two interventions, had a significantly stronger relationship between initial receptive language and post-intervention expressive language age. For expressive target vocabulary size, participants in AC-O showed a strong relationship and those in AC-I a slightly weaker relationship between initial receptive language and expressive target vocabulary size; no significant relationship was found in the SC group. Results emphasize that different interventions may have distinct outcomes for children with higher or lower initial receptive language.

Police officers' volunteering for (rather than being assigned to) Crisis Intervention Team (CIT) training: Evidence for a beneficial self-selection effect.

Officers' volunteering for Crisis Intervention Team (CIT) training-rather than being assigned-is assumed to be an important, beneficial self-selection bias. This bias remains poorly characterized, though CIT officers are more likely to be female and to have had exposure to the mental health field. We determined whether or not self-selection is beneficial with regard to knowledge, attitudes, and skills, as well as level of force used (i.e., no or low force versus any form of physical force) and disposition of subjects, in actual encounters. We compared CIT-trained officers who had volunteered with those who had been assigned using data from two prior, linked studies that compared CIT-trained and non-CIT officers on knowledge, attitudes, and skills (251 CIT-trained officers; 68% had volunteered), as well as behaviors (517 actual encounters provided by 91 CIT-trained officers; 70% had volunteered). Of 28 scores on knowledge, attitudes, and skills compared, six were statistically significantly different (p < .01) and another eight were marginally significant (.01 < p < .05). Furthermore, although CIT officers who had volunteered were more likely to report use of some form of physical force as we had defined it (which included the use of handcuffs), when they did so they were more likely to refer to treatment services and less likely to make an arrest. These effects were apparent even when taking into account effects of gender, having had exposure to the mental health field, empathy, and other covariates. In conclusion, we found evidence for benefits of self-selection/volunteering that should be further characterized, as it appears to be associated with better outcomes with regard to key attitudes, skills, and behaviors.

The relationship of prenatal maternal depression or anxiety to maternal caregiving behavior and infant behavior self-regulation during infant heel lance: an ethological time-based study of behavior.

BACKGROUND: Sensitive and responsive maternal caregiving behavior strengthens infant self-regulatory capacities (HL), but this regulatory role may be diminished in some mothers with second-trimester prenatal exposure to depression and/ or anxiety (MDA). This study examined maternal and infant behavior during infant heel lance (HL) when mothers had or did not have MDA. Ethological methods and micro-analytic approaches capable of distinguishing and comparing time-based patterning in maternal and infant behavior were used to clarify biological mechanisms, such as MDA, that may underlie observed behavior. Aims were to examine group differences in caregiving behavior between mothers with and without MDA 5 min Pre-HL and 5 min Post-H, and relationships between MDA, maternal caregiving behavior and infant pain behavior self-regulation, concurrently. METHODS: At second trimester, mothers were assessed for symptoms of mild-severe depression or anxiety. Mothers whose scores exceeded predetermined cut-off scores on one or more of the mental health measures were allocated to the MDA-exposure group, those below to the non-MDA-exposure group. Reliable observers, blinded to MDA status and study phases, coded video records of the caregiving behavior of each study mother for the full duration of the 5 min Pre-HL and 5 min Post-HL study phases. Group differences and associations between mean measures of maternal mental health scores, time-based measures of maternal behavior, and time-based measures of infant pain behavior regulation (previously coded) were concurrently analyzed using comparative and correlational statistics. RESULTS: MDA-exposed mothers spent significantly more time not embracing, engaging or responding to infant cues than maternal controls Pre-HL and Post-HL. MDA was associated with atypical maternal caregiving behavior, which in turn was related to atypical infant pain behavior self-regulation during and after the HL. CONCLUSION: Our findings have implication for practice. We recommend inclusion of mothers with MDA and their infants in interventions that strengthen the early mother-infant interaction and mother's regulatory caregiving role. MDA and maternal caregiving behavior must be considered in future infant pain studies to examine if they confound effectiveness of mother driven caregiving interventions for neonatal pain. We highlight the importance of examining maternal mental health throughout the perinatal and postnatal trajectory, and particularly the newborn period.

Functional flexibility of infant vocalization and the emergence of language.

We report on the emergence of functional flexibility in vocalizations of human infants. This vastly underappreciated capability becomes apparent when prelinguistic vocalizations express a full range of emotional content--positive, neutral, and negative. The data show that at least three types of infant vocalizations (squeals, vowel-like sounds, and growls) occur with this full range of expression by 3-4 mo of age. In contrast, infant cry and laughter, which are species-specific signals apparently homologous to vocal calls in other primates, show functional stability, with cry overwhelmingly expressing negative and laughter positive emotional states. Functional flexibility is a sine qua non in spoken language, because all words or sentences can be produced as expressions of varying emotional states and because learning conventional "meanings" requires the ability to produce sounds that are free of any predetermined function. Functional flexibility is a defining characteristic of language, and empirically it appears before syntax, word learning, and even earlier-developing features presumed to be critical to language (e.g., joint attention, syllable imitation, and canonical babbling). The appearance of functional flexibility early in the first year of human life is a critical step in the development of vocal language and may have been a critical step in the evolution of human language, preceding protosyntax and even primitive single words. Such flexible affect expression of vocalizations has not yet been reported for any nonhuman primate but if found to occur would suggest deep roots for functional flexibility of vocalization in our primate heritage.

The Contribution of Early Communication Quality to Low-Income Children's Language Success.

The disparity in the amount and quality of language that low-income children hear relative to their more-affluent peers is often referred to as the 30-million-word gap. Here, we expand the literature about this disparity by reporting the relative contributions of the quality of early parent-child communication and the quantity of language input in 60 low-income families. Including both successful and struggling language learners from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, we noted wide variation in the quality of nonverbal and verbal interactions (symbol-infused joint engagement, routines and rituals, fluent and connected communication) at 24 months, which accounted for 27% of the variance in expressive language 1 year later. These indicators of quality were considerably more potent predictors of later language ability than was the quantity of mothers' words during the interaction or sensitive parenting. Bridging the word gap requires attention to how caregivers and children establish a communication foundation within low-income families.

Developing and modifying behavioral coding schemes in pediatric psychology: a practical guide.

OBJECTIVES: To provide a concise and practical guide to the development, modification, and use of behavioral coding schemes for observational data in pediatric psychology. METHODS: This article provides a review of relevant literature and experience in developing and refining behavioral coding schemes. RESULTS: A step-by-step guide to developing and/or modifying behavioral coding schemes is provided. Major steps include refining a research question, developing or refining the coding manual, piloting and refining the coding manual, and implementing the coding scheme. Major tasks within each step are discussed, and pediatric psychology examples are provided throughout. CONCLUSIONS: Behavioral coding can be a complex and time-intensive process, but the approach is invaluable in allowing researchers to address clinically relevant research questions in ways that would not otherwise be possible.

Emotional engagements predict and enhance social cognition in young chimpanzees.

Social cognition in infancy is evident in coordinated triadic engagements, that is, infants attending jointly with social partners and objects. Current evolutionary theories of primate social cognition tend to highlight species differences in cognition based on human-unique cooperative motives. We consider a developmental model in which engagement experiences produce differential outcomes. We conducted a 10-year-long study in which two groups of laboratory-raised chimpanzee infants were given quantifiably different engagement experiences. Joint attention, cooperativeness, affect, and different levels of cognition were measured in 5- to 12-month-old chimpanzees, and compared to outcomes derived from a normative human database. We found that joint attention skills significantly improved across development for all infants, but by 12 months, the humans significantly surpassed the chimpanzees. We found that cooperativeness was stable in the humans, but by 12 months, the chimpanzee group given enriched engagement experiences significantly surpassed the humans. Past engagement experiences and concurrent affect were significant unique predictors of both joint attention and cooperativeness in 5- to 12-month-old chimpanzees. When engagement experiences and concurrent affect were statistically controlled, joint attention and cooperation were not associated. We explain differential social cognition outcomes in terms of the significant influences of previous engagement experiences and affect, in addition to cognition. Our study highlights developmental processes that underpin the emergence of social cognition in support of evolutionary continuity.

From interactions to conversations: the development of joint engagement during early childhood.

This research traces the development of symbol-infused joint engagement during mother-child interactions into the preschool years. Forty-nine children, who had been previously observed as toddlers (L. B. Adamson, R. Bakeman, & D. F. Deckner, ), were systematically observed during interactions with their mothers at ages 3½, 4½, and 5½ during activities related to the past and future, internal states, and graphic systems. Although the amount of symbol-infused joint engagement reached a ceiling by 3½, its focus continued to become more complex and its form more balanced. Individual differences in children's symbol-infused joint engagement were stable across 4 years. These findings highlight both how joint engagement is transformed as conversational skills develop and how it remains rooted in earlier interactions and supported by caregiver's actions.

How European American and Taiwanese mothers talk to their children about learning.

Little cross-cultural research exists on parental socialization of children's learning beliefs. The current study compared 218 conversations between European American and Taiwanese mothers and children (6-10 years) about good and poor learning. The findings support well-documented cultural differences in learning beliefs. European Americans mentioned mental activities and positive affect more, whereas Taiwanese mentioned learning virtues and negative affect more. Mothers, especially European American, reciprocated their children's talk about mental activities, learning virtues, and negative affect. Children, especially Taiwanese, reciprocated their mother's talk about positive affect. Mothers invoked more mental activities and positive affect when discussing good learning, but more learning virtues and negative affect when discussing poor learning. These findings reveal a source of cultural differences in beliefs and potential enculturation.

Active Direction: A new observational measure of African American parenting.

A new observational measure of a culturally salient, supportive African American parenting style, Active Direction, was developed. Ratings were compared to standard qualitative ratings and across two ethnic groups. Active Direction represents the provision of structure to interactions in the form of corrective direction with clear and concise feedback that is assessed for supportiveness rather than simple content or tone. The 7-point rating item was examined in observations of African American (n = 172) and Hispanic American (n = 196) mother-child interactions collected at age 2.5 years in families from low-income households. Ratings were compared and associations to previously reported ratings of the interactions were examined. Active Direction was often observed among the African American mothers (81%) but rarely observed among the Hispanic mothers (16%), with a large effect size difference, supporting the hypothesis that Active Direction may represent a culturally specific approach to parenting for African American parents. Maternal behavior correlations of Active Direction with cognitive stimulation, intrusiveness, scaffolding, and calm authority and with child affiliative obedience and dyadic routines and rituals were significantly higher and detachment significantly lower in the African American compared to the Hispanic sample. The new measure of Active Direction, centered around culturally salient values and differences in both historical and lived experiences, addresses characteristics of parenting in African American families that are supportive of their children's development and provides a fruitful direction for future research.

Temporal Relationships Between Nursing Home Staff Care Approaches and Behaviors of Residents With Dementia During Mealtimes: A Sequential Analysis.

Background and Objectives: Optimal dyadic interactions are critical to quality mealtime care and outcomes. Prior work supports associative relationships between staff approaches and individual mealtime behaviors, yet evidence on temporal relationships is limited. This study examined temporal associations between staff approaches and resident behaviors during mealtimes. Research Design and Methods: Videotaped mealtime observations (N = 160) involving 36 staff and 27 residents (53 staff-resident dyads) in 9 nursing homes were analyzed. Sequential analyses using 5-, 10-, and 15-second time windows were conducted for resident positive, neutral, and challenging behaviors as antecedents as well as consequences of staff person-centered and task-centered approaches. Results: Residents exhibited positive verbal (35.0%) and positive/neutral nonverbal (12.6%) behaviors, as well as challenging behaviors including functional impairments (27.7%) and resistive behaviors (24.7%). Staff primarily used person-centered approaches (54.1% verbal, 40.3% nonverbal); task-centered approaches were less frequent (5.6%). Immediately (within 5 seconds) after staff person-centered approaches, resident positive/neutral and resistive behaviors were more likely, and functional impairments less likely. After staff task-centered approaches, resident positive verbal and resistive behaviors were less likely. After resident positive/neutral behaviors, staff person-centered approaches were more likely. After resident functional impairments, staff person-centered verbal approaches were less likely, and task-centered approaches more likely. After resident resistive behaviors, all staff approaches were more likely. The strength of temporal relationships diminished in 10-second and 15-second time windows. Discussion and Implications: Staff-resident positive interactions were associated with more subsequent positive interactions. Person-centered care was associated with fewer subsequent resident functional impairments and more subsequent resistive behaviors. Resident resistive behaviors were associated with more subsequent person-centered and task-centered care. Findings confirm the importance of facilitating positive staff-resident interactions and managing functional impairments using person-centered care. Resistive behaviors require additional awareness and attention beyond commonly used person-centered care approaches. Further investigation of temporal relationships is needed using larger diverse samples.

Longitudinal Structural and Diffusion-Weighted Neuroimaging of Young Children Born Preterm.

BACKGROUND: Children born preterm are at risk for diffuse injury to subcortical gray and white matter. METHODS: We used a longitudinal cohort study to examine the development of subcortical gray matter and white matter volumes, and diffusivity measures of white matter tracts following preterm birth. Our participants were 47 children born preterm (24 to 32 weeks gestational age) and 28 children born at term. None of the children born preterm had significant neonatal brain injury. Children received structural and diffusion weighted magnetic resonance imaging scans at ages five, six, and seven years. We examined volumes of amygdala, hippocampus, caudate nucleus, putamen, thalamus, brainstem, cerebellar white matter, intracranial space, and ventricles, and volumes, fractional anisotropy, and mean diffusivity of anterior thalamic radiation, cingulum, corticospinal tract, corpus callosum, inferior frontal occipital fasciculus, inferior longitudinal fasciculus, temporal and parietal superior longitudinal fasciculus, and uncinate fasciculus. RESULTS: Children born preterm had smaller volumes of thalamus, brainstem, cerebellar white matter, cingulum, corticospinal tract, inferior frontal occipital fasciculus, uncinate fasciculus, and temporal superior longitudinal fasciculus, whereas their ventricles were larger compared with term-born controls. We found no significant effect of preterm birth on diffusivity measures. Despite developmental changes and growth, group differences were present and similarly strong at all three ages. CONCLUSION: Even in the absence of significant neonatal brain injury, preterm birth has a persistent impact on early brain development. The lack of a significant term status by age interaction suggests a delayed developmental trajectory.