Multilevel Growth Curve Models Research Articles

Multidimensionality of Well-Being and Spillover Effects Across Life Domains: How Do Parenthood and Personality Affect Changes in Domain-Specific Satisfaction?

Whether having children improves our well-being is a long-standing topic of debate. Demographic and sociological research has investigated changes in individuals’ overall well-being and partnership satisfaction when they become parents. However, little is known about how becoming parent may produce vulnerability—observable as an enduring decrease in well-being—in life domains that are strongly interdependent with the family domain, such as work and leisure. Linking life-course and personality psychology perspectives, the authors examine the trajectories of subjective well-being—measured as satisfaction with life, work, and leisure—3 years before and 3 years after the transition to parenthood. The authors particularly focus on the moderating effects of gender and personality. Using data from the German Socio-Economic Panel (1984–2013) and multilevel growth curve modeling, the authors show strong gender-based vulnerability in how people react to parenthood. Although men display a nonlinear pathway of decreasing life satisfaction and a stable trajectory of job satisfaction, women experience more changes in their satisfaction with work and more dramatic decreases in leisure satisfaction. Contrary to most of our expectations, the moderating effects of personality were modest. Extraversion influenced the trajectories of work satisfaction, whereas neuroticism and conscientiousness affected the pathway of leisure satisfaction for women only. This article shows that the transition to parenthood influences well-being trajectories in specific domains, and this influence differs between women and men.

Testing a Matching Hypothesis for Emerging Adults in Project MATCH: During-Treatment and One-Year Outcomes.

Compared with older adults, emerging adults (18-29 years old) entering treatment typically have less severe alcohol use consequences. Also, their unique clinical presentations (e.g., modest initial abstinence motivation) and developmental contexts (e.g., drinking-rich social networks) may make a straightforward implementation of treatments developed for adults less effective. Yet, this has seldom been examined empirically. This study was a secondary analysis of Project MATCH (Matching Alcoholism Treatments to Client Heterogeneity) data examining (a) overall differences between emerging adults and older adults (≥30 years old) on outcomes during treatment and at 1-year follow-up, and (b) whether emerging adults had poorer outcomes on any of the three Project MATCH treatments in particular. Participants were 267 emerging adults and 1,459 older adults randomly assigned to individually delivered cognitive-behavioral therapy (CBT), motivational enhancement therapy (MET), or 12-step facilitation (TSF). Multilevel growth curve models tested differences on percentage of days abstinent (PDA) and drinks per drinking day (DDD) by age group and treatment assignment. During treatment, compared with older adults, emerging adults reported more DDD but similar PDA. Further, emerging adults assigned to TSF had less PDA and more DDD than emerging adults and older adults assigned to CBT or MET during treatment (i.e., emerging adults in TSF has poorer outcomes initially), but this matching effect was not evident at 1-year follow-up. This study is among the first to test age group differences across three psychosocial interventions shown to be efficacious treatments for alcohol use disorder. Although emerging adults generally did as well as their older counterparts, they may require a more developmentally sensitive approach to bolster TSF effects during treatment.

Trajectories of neighborhood attainment after prison

A potentially important but understudied aspect of prisoner reentry is the neighborhood environments experienced by formerly incarcerated people. We know that many formerly incarcerated people return to very disadvantaged neighborhood environments and that returning to disadvantaged neighborhoods after prison increases the risk of recidivism and reduces employment. Yet very little is known about the social, economic, and institutional processes that sort formerly incarcerated people into different neighborhoods after release or their trajectories of neighborhood attainment over time. Motivated by a conceptualization of prisoner reentry and reintegration as a process that unfolds over time, we examine trajectories of neighborhood environments after release. Motivated by the literature on neighborhood attainment, social capital, and the role of criminal justice institutions in structuring the lives of former prisoners, we examine sources of variation in neighborhood attainment. We use administrative data from the Michigan Department of Corrections on formerly incarcerated people paroled in 2003 and followed for two years after release. Descriptive results from a latent class trajectory model show that most white and black formerly incarcerated people experience flat trajectories, with little upward or downward residential mobility over time. Findings from multi-level growth curve models suggest that institutional factors are particularly important for the neighborhood attainment of whites, while human capital and social ties are particularly important for blacks. Among both blacks and whites, pre-prison and first post-prison neighborhood conditions exhibit a strong association with post-prison neighborhood attainment, although these associations are larger for blacks than whites.

Relationship between employment histories and frailty trajectories in later life: evidence from the English Longitudinal Study of Ageing.

BackgroundGiven the acceleration of population ageing and policy changes to extend working lives, evidence is needed on the ability of older adults to work for longer. To understand more about the health impacts of work, this study examined the relationship between employment histories before retirement and trajectories of frailty thereafter.MethodsThe sample comprised 2765 women and 1621 men from the English Longitudinal Study of Ageing. We used gendered typologies of life-time employment and a frailty index (FI). Multilevel growth curve models were used to predict frailty trajectories by employment histories.ResultsWomen who had a short break for family care, then did part-time work till 59 years had a lower FI after 60 years than those who undertook full-time work until 59 years. Women who were largely family carers or non-employed throughout adulthood, had higher levels of frailty at 60 years but experienced a slower decline with age. Men who worked full-time but early exited at either 49 or 60 years had a higher FI at 65 years than those who worked full-time up to 65 years. Interaction between employment histories and age indicated that men in full-time work who experienced an early exit at 49 tended to report slower declines.ConclusionsFor women, experiencing distinct periods throughout the lifecourse of either work or family care may be advantageous for lessening frailty risk in later life. For men, leaving paid employment before 65 years seems to be beneficial for decelerating increases in frailty thereafter. Continuous full-time work until retirement age conferred no long-term health benefits.

Consequences of Misspecifying Across-Cluster Time-Specific Residuals in Multilevel Latent Growth Curve Models

This Monte Carlo study evaluates, in the context of multilevel latent growth curve models, the consequences of under- and overspecifying across-cluster time-specific residuals (i.e., ) on the estimation of the fixed effects, their corresponding standard errors, the variances and covariances of the random effects, Type I error rates, and the statistical power of detecting fixed effects. The results show that underspecifying with all elements of fixed at zero results in a large underestimation of the between- and within-level random effect and standard errors of fixed effect estimates, which, in turn, leads to serious bias in significant testing. Underspecifying with diagonal elements of constrained to equality, or overspecifying with diagonal elements of constrained to equality or freely estimated and residual covariances fixed at zero also leads to bias in the estimation of the between- and within-level random effects. Implications of the compensatory relationship occurring at the covariance level are discussed.

NEIGHBORHOOD ATTAINMENT OVER THE ADULT LIFE COURSE.

This study uses data from the Panel Study of Income Dynamics, in conjunction with neighborhood-level data from the U.S. decennial census and American Community Survey, to examine the trajectory of individuals' neighborhood characteristics from initial household formation into mid-to-late adulthood. Multilevel growth curve models reveal both different starting points and different life-course trajectories for blacks and whites in neighborhood economic status and neighborhood racial composition. Among respondents who first established an independent household during the 1970s, improvement in neighborhood income over the adult life course is substantially greater for whites than for blacks, while the racial difference in the percentage of neighbors who are non-Hispanic white narrows slightly with age. Racial differences in the characteristics of neighborhoods inhabited during adolescence help to explain racial differences in starting points and, to a lesser extent, subsequent trajectories of neighborhood attainment. Residing in an economically advantaged neighborhood during adolescence confers greater subsequent benefits in neighborhood economic status for whites than for blacks. These findings are used to begin developing a life-course perspective on neighborhood attainment.

The role of socioeconomic factors in Black-White health inequities across the life course: Point-in-time measures, long-term exposures, and differential health returns

Research links Black-White health disparities to racial differences in socioeconomic status (SES), but understanding of the role of SES in racial health gaps has been restricted by reliance on static measures of health and socioeconomic well-being that mask the dynamic quality of these processes and ignore the racialized nature of the SES-health connection. Utilizing twenty-three years of longitudinal data from the Panel Study of Income Dynamics (1984–2007), this study uses multilevel growth curve models to examine how multiple dimensions of socioeconomic well-being—including long-term economic history and differential returns to SES—contribute to the life course patterning of Black-White health disparities across two critical markers of well-being: body mass index (N = 9057) and self-rated health (N = 11,329). Findings indicate that long-term SES exerts a significant influence on both body mass index and self-rated health, net of point-in-time measures, and that Black-White health gaps are smallest in models that adjust for both long-term and current SES. I also find that Blacks and Whites receive differential health returns to increases in SES, which suggests that other factors—such as neighborhood segregation and exposure racial discrimination—may restrict Blacks from converting increases in SES into health improvements in the same way as Whites. Together, these processes contribute to the life course patterning of Black-White health gaps and raise concerns about previous misestimation of the role of SES in racial health disparities.

Short- and Mid-Term Effects of Violent Victimization on Delinquency

The present study investigates how adolescents' experiences of violent victimization exert short- and mid-term effects on their involvement in delinquency. The study compares and contrasts delinquency trajectories of youths whose experiences of violent victimization differ. A multilevel growth-curve modeling approach is applied to analyze data from five waves of the National Youth Survey. The results show that, although delinquency involvement increases as youths experience violent victimization, delinquency trajectories differ with the type of violent victimization, specifically, parental versus non-parental victimization. Violent victimization by parents produced a sharp initial decline in delinquency (short-term effect) followed by a rapid acceleration (mid-term effect). In turn, non-parental violence showed a stable trend over time. The findings have important implications for prevention and treatment services.

Second order electoral rules and national party systems: The Duvergerian effects of European Parliament elections

The effects of electoral rules on party systems have been well known since Duverger first proposed his famous law. Often considered ‘second order’ in terms of issues and voting behaviour, many European Parliament elections are held under different electoral rules to national elections. This article examines the consequences of these differences and hypothesizes that where a more permissive electoral system is used for European Parliament elections, the size of the party system at European Parliament elections will grow towards what we would expect from the European Parliament electoral rules in isolation, and that this will lead to a subsequent growth in the size of the national party system. Using multi-level mixed-effect growth curve modelling support is found for both these hypotheses.

High perceived social support protects against the intergenerational transmission of obesity: The Cardiovascular Risk in Young Finns Study

AimsOur aims were to assess whether offspring social support moderates the relationship between parental body mass index (BMI) and offspring BMI. MethodsA prospective design was used with an analytic sample of 1049 participants from Finland (the offspring) who were 35–50years old in 2012 when adulthood BMI was measured. Parental BMI was self-reported at baseline in 1980. Offspring social support was measured in 2007 when participants were 30–45years old. Linear and logistic regression was used to examine whether there was an interaction between parental BMI and offspring social support when predicting offspring BMI in adulthood. An analysis of simple slopes and multilevel growth curve modeling were used to further examine the interaction. ResultsThe interaction between maternal BMI and offspring social support was significantly and negatively related to offspring BMI in adulthood (β=−0.068, R2 change=0.005, p=0.015) in the fully adjusted model which also adjusted for parental occupational status and offspring depressive symptoms. The logistic regression supported these results, with the interaction between maternal overweight (BMI≥25kg/m2) and offspring social support negatively associated with offspring overweight in adulthood (odds ratio=0.74, 95% confidence interval, 0.56 to 0.98). The growth curve analysis further demonstrated that high maternal BMI predicts more rapidly rising offspring BMI in those reporting low social support compared to high social support. ConclusionsOur results suggest that social support protects against the intergenerational transmission of obesity and therefore presents an important opportunity for obesity prevention efforts.

Interactions Between Drinking Motives and Friends in Predicting Young Adults' Alcohol Use.

While drinking motives are well-established proximal predictors of alcohol use, less is known about their role in event-level drinking behavior. The present study examines whether the interaction between individuals' drinking motives and the number of friends present at a given moment can predict alcohol consumption over the course of the evening. Using the Internet-based cell phone-optimized assessment technique (ICAT), 183 young adults (53.0% female, mean age = 23.1) in French-speaking Switzerland completed cell phone questionnaires every Thursday, Friday, and Saturday evening over five weekends. A total of 7205 questionnaires completed on 1441 evenings were analyzed. Drinking motives and gender were assessed at baseline, while the hourly alcohol consumption rate and number of friends present were assessed at 8p.m., 9p.m., 10p.m., 11p.m., and midnight. Multilevel growth curve models with time-invariant and time-varying covariates were estimated for men and women separately. Among women, enhancement motives were associated with an increase in the hourly alcohol consumption rate over the course of the evening (b = .025; p < .05). The impact of the number of friends present on the hourly consumption rate was stronger among those women who scored high on coping motives at baseline (b = .028; p < .05). Among men, drinking motives were found to have no moderating effects. Results highlight the role of drinking motives and their interactions with situational characteristics in determining event-level drinking, especially among women. Strategies to prevent risky weekend drinking should focus on both the social environment in which drinking takes place (e.g., the drinking group) and individual drinking motives.

Sleep duration and the cortisol awakening response in dementia caregivers utilizing adult day services.

Sleep complaints are common among caregivers and are associated with detriments in mental and physical health. Cortisol, a biomarker of the stress process, may link sleep with subsequent health changes in caregivers. The current study examines whether sleep duration is directly associated with the cortisol awakening response (CAR), or whether it is moderated by Adult Day Services (ADS) use, an intervention found previously to influence daily CAR by reducing stressor exposure. Associations were examined in caregivers (N = 158) of individuals with dementia (IWD) on days when IWDs attended ADS and days when IWDs did not attend ADS. Data were gathered over 8 consecutive days. Caregivers were primarily female (87.3%) with a mean age of 61.59. A multilevel growth curve model tested the association of an interaction of today's ADS use and last night's sleep duration with today's CAR as the outcome. The interaction between ADS use and within-person sleep duration was significant such that when an individual sleeps longer than their average but does not use ADS, they have a smaller or blunted CAR. On the other hand when an individual sleeps longer than their average and uses ADS, they have a higher but nonsignificant CAR. Sleeping shorter than usual was associated with a dynamic rise regardless of ADS use. Findings indicate that ADS use moderates the association between sleep duration and CAR such that longer than average sleep is associated with blunted, dysregulated cortisol patterns only on non-ADS days.

Regional Partnerships and Metropolitan Economic Development

ABSTRACT:Regional partnerships have grown popular as mechanisms to address public goods that transcend local boundaries, but we know little about their effectiveness. For example, what impact do regional economic development partnerships (REDPs), cooperative organizations of local governments, nonprofits and business organizations have on the economies of metropolitan areas? This article employs survival analysis and multilevel growth curve models to examine how the emergence of regional partnership arrangements influences patterns of economic development in U.S. metropolitan areas. The results suggest that, whereas these organizations do not make a great difference in some metro areas, in densely populated and politically fragmented metropolitan areas personal incomes, business firms, and employment grew significantly with the emergence of REDPs. Furthermore, state level factors, such as intergovernmental grant funding, are found to have positive influences. In conclusion, we discuss regional partnerships as solutions to institutional collective action problems in economic development and other policy arenas.

Trajectories of Change in Obesity among Tehranian Families: Multilevel Latent Growth Curve Modeling.

Objectives. To evaluate the trajectories of change in obesity within and between Tehranian families, who participated in the Tehran Lipid and Glucose Study (TLGS). Methods. This study is a family-based longitudinal design, in four waves. A total of 14761 individuals, within 3980 families, were selected. Three anthropometric measurements, body mass index (BMI), waist circumference (WC), and a body shape index (ABSI), were recorded. Multilevel latent growth curve modeling (MLGCM) approach was used for evaluating the change trajectories in obesity within and between the families. Results. The mean age of the subjects in the present study was 33.28 ± 19.01 (range 3–89 years) and 50.1% were male. Obesity was significantly increased (P < 0.001). Individuals with more fat become obese slower, whereas families with more fat become obese faster (P < 0.001). The initial value and growth rate of WC and ABSI were greater in men than in women, while this result is contrary to BMI (P < 0.001). Conclusions. Our findings demonstrated that there is an alarming increase in the obesity trend in Tehranian families. The important role of the family in the prevention of obesity is highlighted, underlining the need for public health programs, as family centered educations to lifestyle modification, which can address this emerging crisis.

Examining within-person and between-person effects of victimization and social risk on cannabis use among emerging adults in substance-use treatment.

The goals of this study were to examine associations between within- and between-person social risk and victimization and cannabis use among emerging adults in substance-use treatment. We also tested gender differences for both victimization and social risk. Participants consisted of 3,052 emerging adults (M(age) = 20.0 years; SD = 2.21) entering substance-use treatment in a wide range of treatment centers across the United States. Individuals were assessed on all measures at baseline 3, 6, and 12 months. We fitted a taxonomy of multilevel growth curve models to test main effects, and interactive relations between within- and between-person social risk, victimization, and gender on cannabis use. Several significant interactions were evident. Irrespective of gender, within-person increases in social risk were associated with contemporaneous increases in cannabis use; however, the magnitude of this relation was comparatively more pronounced for men. Similar gender differences emerged between individuals. Males experiencing heightened social risk over time tended to show high levels of early cannabis use. Simple slope analyses revealed that reporting more (+1 SD) social risk than one's own mean resulted in significant increases in cannabis use for both men and women. Cross-level simple slope analyses revealed no differences in cannabis use among individuals reporting low (-1 SD) social risk and victimization, but significant increases in cannabis use for individuals reporting high (+ 1 SD) victimization and social risk. Results demonstrate support for gender differences in social risk on cannabis use and the importance of considering within-person effects. (PsycINFO Database Record

Relative Contributions of a Set of Health Factors to Selected Health Outcomes.

Although many researchers agree that multiple determinants impact health, there is no consensus regarding the magnitude of the relative contributions of individual health factors to health outcomes. This study presents a method to empirically estimate the relative contributions of health behaviors, clinical care, social and economic factors, and the physical environment to health outcomes using nationally representative county-level data and statistical approaches that account for potential sources of bias. The analyses for this study were conducted in 2014. Data were from the 2010-2013 County Health Rankings & Roadmaps. Data covered 2,996 of 3,141 U.S. counties. Ordinary least squares modeling was used as a baseline model. Multilevel latent growth curve modeling was used to estimate the relative contributions of health factors to health outcomes while accounting for measurement errors and state-specific characteristics. Almost half of the variance of health outcomes was due to state-level variation rather than county-level variation. When adjusted for measurement errors and state-level variation using multilevel latent growth curve modeling, the relative contribution of clinical care decreased and that of social and economic factors increased compared with the baseline model. This study presents how potential sources of bias affected the estimates of the relative contributions of a set of modifiable health factors to health outcomes at the county level. Further verification of these approaches with other data sources could lead to a better understanding of the impact of specific health determinants to health outcomes, and will provide useful information on policy interventions.

A spatio-temporal analysis of academic performance at the Basic Education Certificate Examination in Ghana

Over the last decade, Ghana has more than tripled investment in its basic education system. Consequently, the country has made huge educational gains, primarily in providing universal access to basic education. However, many stakeholders are worried that academic performance is lagging because of disproportional attention to accessing basic education. Discussion of these concerns is hampered by ongoing disagreement about the true trajectory of academic performance at the basic education level and the widespread nature of students' lagging academic performance. In part, this disagreement stems from the failure of empirical studies to comprehensively examine trends in academic performance standards at the basic education level by concurrently considering a geographical and longitudinal perspective. Thus, this study examines the spatio-temporal trends of academic performance at the junior high school level since 2009 by using multilevel growth curve modeling, spatial statistics, and district-level longitudinal data. Results reveal 3 statistically distinct trajectories of academic performance: erratic, accelerating, and decelerating changes. Results also show that rural–urban gaps explain 31% of the performance trajectories, a trend which is expected to persist in the long term. In addition, we find extreme variations in academic performance within rural areas. Given the varying trajectories and geographical variability in academic performance, we suggest a localized approach to addressing challenges of low academic achievement at the basic education level in Ghana.

Donor catch-up growth after laser surgery for twin–twin transfusion syndrome

ObjectiveTo assess fetal growth after laser surgery for TTTS at the time of prenatal diagnosis, birth, and at 2years of age. Design/methodsGrowth data were collected from surviving children treated between 2007 and 2010 as part of a study to assess neurodevelopment at 24months (±6weeks) corrected age. Fetal weights were obtained via ultrasound using Hadlock's formula at the time of preoperative assessment for laser surgery. Birth weights were recorded by the staff at the delivering institutions. Weights at 2years corrected age were recorded at the time of neurodevelopmental testing. Weights were converted into percentiles according to standard growth curves. Growth restriction was defined as <10th percentile for given age. Multilevel latent growth curve models in Mplus (twins nested in families) examined weight change over time as a function of donor status, and repeated measures ANOVA was utilized to assess in donor–recipient weight discordance over time for twin pairs. Results99 of 206 children (56 of 130 families) were studied. There were no differences between enrolled and non-enrolled patients in donor/recipient status and survival rates, fetal demise, intrauterine growth restriction, Quintero stage, and gestational age of surgery or delivery. 48.5% were donors. The median fetal, birth, and 2-year weights for all twins were 288g, 1.9kg, and 11.8kg, respectively, and the overall prevalence of growth restriction was 28%, 22%, and 3%, respectively. Growth restriction rates at prenatal diagnosis were 56% in donors vs. 2% in recipients (OR=64.3, p<0.001); at birth, 35% vs. 10% (OR=5.0, p<0.01); and at 2years, 6% vs. 0%. Donors showed significant gains in weight percentile (B=13.1, p<0.001) and a significant decrease in growth restriction rates over time (B=−1.6, p<0.001). Weight discordance between donor and recipient pairs also significantly decreased over time (linear F(1,42)=54.34, p<0.001). ConclusionsAfter laser surgery for TTTS, donor twins exhibit significant catch-up growth by two years of age.

The Synergy of Family and Neighborhood on Rural Dating Violence Victimization.

Rural adolescents are at high risk for dating violence victimization (DVV), which has serious negative consequences. Understanding more about the conditions that increase DVV risk for rural adolescents is needed to inform prevention efforts. In response to calls for examining the influence of upper levels of the social ecology on adolescent dating violence, this study examined whether associations between the family context and physical DVV were conditioned by the characteristics of the neighborhoods in which the family resided. Data were from a multi-wave longitudinal study of 3,236 rural adolescents nested in 65 block groups, which defined neighborhoods. Data were collected between 2003 and 2005. Multilevel growth curve modeling was conducted in 2014 to test hypothesized synergistic effects of the family and neighborhood on trajectories of physical DVV from grade 8 to 12. Low parental closeness was a DVV risk in residentially stable (p<0.001), but not unstable, neighborhoods. Family aggression was a DVV risk, regardless of neighborhood characteristics (p=0.001). Low parental monitoring and rule setting were not DVV risks and their effects were not moderated by neighborhood characteristics. Neighborhood ethnic heterogeneity was significantly (p<0.05) positively associated with DVV, but neighborhood economic disadvantage, social disorganization, and violence were not associated with DVV. None of the effects varied by sex of the adolescent, across time (grade), or by the combination of sex and time. Findings demonstrate the importance of considering the family and neighborhood, and particularly their synergistic effects in efforts to prevent adolescent DVV.

Intensive short-term dynamic residential treatment program for patients with treatment-resistant disorders

BackgroundThe study investigated the effectiveness of an Intensive Short-Term Dynamic (ISTDP) residential treatment program for patients with treatment resistant anxiety- and/or depressive disorders, with and without comorbid personality disorders. MethodA non-randomized controlled trial examined the effects of an eight week intensive residential treatment program based on principles from ISTDP. Patients (N=60), who had repeated prior treatment failure for current mental disorder, sufficient dysfunction to warrant hospitalization, and evidencing capacity to take an intrapsychic perspective on own problems, were included. Outcome variables included measures of target complaints (depression/anxiety, social role dysfunction, and interpersonal distress), general symptom distress, and interpersonal functioning. Measures were administered throughout and after treatment. Change was assessed by multilevel growth curve modeling. Changes during and after treatment were compared to those reported by a sub-sample of wait-list controls taking treatment as usual (N=30). ResultsThe treatment group evidenced significant improvements on all measures. By contrast, receiving treatment as usual while on the wait-list did not yield significant changes. Effect sizes in the treatment group were consistently large at both termination and follow-up. Fourteen months after treatment 50.0% of patients had recovered in terms of target complaints. Approximately 53.3% and 48.3%, respectively, had recovered in terms of general symptom distress and interpersonal functioning. LimitationsLimitations included a relatively small sample size, inability to discern the effectiveness of separate components of the treatment program, and lack of randomization of patients to wait-list and treatment. ConclusionISTDP-based residential treatment with an eight-week time-limit appears to be effective for alleviating common and severe, treatment resistant mental disorders. The treatment program was superior to receiving treatment as usual while on the wait-list. Participation in the program quickly reduced target complaints, symptoms and interpersonal problems for patients who, based on previous treatment experiences, were expected to fare poorly in treatment. Gains were consistently maintained or improved further at follow-up. Results are promising for patients with chronic debilitating problems who often do not profit from traditional psychiatric treatment.