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D C Rowe

Publications and source records attributed to D C Rowe.

At least 37 records · Page 2Linked to original sources
PubMed1997

Effects of censored variables on family studies.

In the present paper effects of censored variables on estimates of genetic and environmental influences were studied. Analytic results showed with 50% censoring, about 15-20% of the variance may be attributed to the wrong source and that this amount increases rapidly with more than 70% censoring. Censoring effects on comparisons between different genetic studies, subgroups within a study (e.g., sex or age groups), or different behaviors (e.g., the heritabilities of delinquency and depression) were also examined. Results indicated that censoring may be quite influential for these kinds of comparisons. For instance, it was demonstrated that, especially for unstandardized solutions, small initial group differences in means can lead to seriously biased conclusions concerning the resemblance in biometric parameters. Finally, a stimulation study supported the applicability of the general analytical results and showed that summed scores of censored Likert-type items may be seriously affected by censoring.

Analysis of Variance↗
PubMed1997

In the eye of the beholder? Parental ratings of externalizing and internalizing symptoms.

Variations in ratings of externalizing and internalizing symptoms may contain a trait (i.e., shared view) component when behavioral symptoms that generalize across context are perceived and an individual view component when they are misperceived of when each informant has access to different symptoms. Using a LISREL model, we estimated that the trait and the important-specific, individual view components in parental ratings of externalizing and internalizing symptoms of adolescent siblings. This model demonstrated that mothers' and fathers' ratings contained a substantial individual view component (from 21% to 50% of total rating variance, depending on rater and trait). Except for fathers' ratings of internalizing symptoms (13%), parental ratings also contained a substantial trait component (42% to 58%). Mother's, fathers', and child's ratings may be averaged to estimate a trait of externalizing. To estimate an internalizing trait, it may be best to combine just the mother's rating with the child's self-rating.

Adolescent↗
PubMed1997

Continuity and change in children's social maladjustment: a developmental behavior genetic study.

Two developmental models were used to study genetic and environmental mechanisms underlying continuity and change in children's maladjustment. The transmission model assumed that successive levels of functioning were causally linked and that earlier experiences or prior genetic influences affected later maladjustment. The liability model related continuity in problem behavior to stable underlying environmental or genetic factors. The analyses pertained on average to 436 pairs of full siblings, 119 pairs of half siblings, and 122 pairs of cousins for whom maternal ratings of problem behaviors were available at ages 4-6, 6-8, and 8-10. Nonshared environmental influences appeared to be most important for changes in children's problem behaviors and did not have significant effects on age-to-age continuity. To represent the genetic and shared environmental mechanisms underlying stability in problem behavior, the authors preffered liability models without time specific effects.

Adult↗
PubMed1997

Origins of familial similarity in parenting: a study of twins and adoptive siblings.

Parents of young children completed questionnaires that assessed attitudes toward parenting and specific parenting practices, the emotional atmosphere of the home, and parental personality. These parents were themselves either identical twins (n = 90), fraternal twins (n = 56), or adoptive siblings (n = 40). Model-fitting results implicate modest genetic effects on affect-related aspects of parenting, such as parental warmth. The results add new dimensions to the growing body of literature that documents genetic influences on measures of the family environment and suggest that child-rearing variables are significantly related to the major factors of parental personality.

Adoption↗
PubMed1993

Social contagion and adolescent sexual behavior: a developmental EMOSA model.

Epidemic Models of the Onset of Social Activities (EMOSA models) describe the spread of adolescent transition behaviors (e.g., sexuality, smoking, and drinking) through an interacting adolescent network. A theory of social contagion is defined to explain how social influence affects sexual development. Contacts within a network can, with some transition rate or probability, result in an increase in level of sexual experience. Five stages of sexual development are posited. One submodel proposes a systematic progression through these stages; a competing submodel treats each as an independent process. These models are represented in sets of dynamically interacting recursive equations, which are fit to empirical prevalence data to estimate parameters. Model adjustments are substantively interpretable and can be used to test for and better understand social interaction processes that affect adolescent sexual behavior.

Adolescent↗
PubMed1992

Sibling delinquency and the family environment: shared and unshared influences.

Few family studies of delinquency have focused on siblings. We use a sibling research design to evaluate shared (i.e., family) and unshared environmental influences on delinquency. The 15-22-year-old adolescent siblings were nationally representative, and uniquely, in families of 2 to 4 siblings. No unshared family environmental influences were found for sisters and for mixed-sex siblings, but they may exist for brothers. The data suggested substantial shared environmental and/or shared genetic influences for siblings: the median sibling correlations, averaged over family sizes, were: brothers, r = .30; sisters, r = .28, and mixed sex, r = .21.

Adolescent↗
PubMed1991

An 'epidemic' model of adolescent sexual intercourse: applications to national survey data.

This paper applies models of the onset of adolescent sexual intercourse using national data from Denmark and the USA. The model gave excellent fits to data on Danish Whites and a good fit to American Whites, but the model-fits for American Blacks and Hispanics were not as good. The weakness of the latter model fits may reflect either real processes that the model does not capture or problems in the reliability of adolescent sexuality data.

Adolescent↗
PubMed1991

Adolescent smoking and drinking: are they "epidemics"?

During adolescence, cumulative prevalences of ever using alcohol and ever smoking a cigarette increase systematically and dramatically. We applied a statistical theory of the transmission of epidemic infectious disease to model life-time prevalences of smoking and drinking. Alcohol use prevalences fit closely to a logistic curve used to model an epidemic process that assumed adolescents have random contacts with one another each year. An "adequate contact" will convert a nondrinker to drinking status if he/she is contacted; drinkers average .48 adequate contacts per year. Smoking prevalences were fit assuming both that the entire population was "at risk" and that some individuals were "immune": the mean contact parameter was .28 for smoking if no immune class was assumed and .77 if an immune class was assumed. Extensions of these epidemic process models could include individual differences in contact rates and transitions among several smoking or drinking statuses (e.g., non-user, experimenter, regular user and recovered user).

Adolescent↗
PubMed1983

A biometrical analysis of perceptions of family environment: a study of twin and singleton sibling kinships.

Biometrical genetic analysis was applied to sibling and twin kinship data on 2 dimensions of perceived home environment. Correlations on 1 dimension, Restrictiveness-Permissiveness, were equal and significant for all kinships: MZ twins, DZ twins, same-sex siblings, and opposite-sex siblings significant for all 4 kinships: MZ twins, DZ twins, same-sex siblings, and opposite-sex siblings (r greater than .40). An E2-E1 biometrical model fitted Restrictiveness-Permissiveness, implying that treatments common to siblings create agreement about perceived environment. As intrapair differences were the same for all 4 kinships under this model, the equal environments assumption of the twin method was supported. In contrast, the Acceptance-Rejection dimension fitted a G-E1 model that makes the assumption that sibling similarity is the result of genetic factors and postulates an absence of shared environmental influences. This finding suggests that this aspect of home environment may depend as much on the child's inherited traits as on actual treatments and is in accord with the genetic analysis of individual traits in that developmentally effective environmental factors do not appear to be common to siblings.

Environment↗
PubMed1979

A multivariate twin analysis of within-family environmental influences in infants' social responsiveness.

Observational measures of social responsiveness were obtained for twin infants. The structure of within-family environmental influences was assessed by correlating identical twin pair differences for 13 behaviors in seven social settings. Factor analysis of the difference score matrix yielded one interpretable factor. This factor indicated that within-family environmental influences were not completely random but may exert a systematic effect on social behavior in several situations.

Child, Preschool↗
PubMed1977

A twin study of temperament in young children.

Temperament was assessed in 182 young children (91 pairs of twins, average age of 3.6 years) with use of the Colorado Childhood Temperament Inventory (CCTI). The CCTI represents a merger of dimensions suggested by two approaches to the study of the development of temperament: the New York Longitudinal Study and Buss and Plomin's temperament theory. Of the six traits measured by the CCTI, genetic factors were implicated in the etiology of five (sociability, emotionality, activity, attention span-persistence, and soothability). One trait, reaction to food, showed no genetic influence and indicated strong between-family environmental effects. A negative correlation between emotionality and soothability may also have a genetic basis. These results suggest that the development of certain personality traits--those that we include as temperament--are substantially influenced by heredity.

Attention↗
PubMed1977

Temperament in early childhood.

The structure of temperament proposed by the New York Longitudinal Study (NYLS) of Thomas and collaborators (1963, 1968) was compared to Buss and Plomin's (1975) EASI temperament theory. An objective inventory was developed for the NYLS temperaments. Mothers rated 182 children on both NYLS and EASI temperaments. Only two of the nine NYLS dimensions, attention span-persistence and distractibility, were supported by factor analysis. The four EASI dimensions (emotionality, activity, sociability, and impulsivity) were replicated. A similar sociability factor emerged from both the NYLS and EASI systems, but other temperaments were unique. The NYLS and EASI systems were merged to form the Colorado Childhood Temperament Inventory, a parental rating instrument for children 1-6 years of age.

Attention↗
PubMedDate not supplied

An "epidemic" model of sexual intercourse prevalences for black and white adolescents.

In adolescence (12-16 years), the prevalence of sexual intercourse increases each year. To explain the increasing yearly prevalences, we propose a recursive equation model of onset of adolescent sexual intercourse. The model allows for an "epidemic" process (the transmission of sexuality from a nonvirgin to a virgin) and a nonepidemic process (two virgins progressing to sexual intercourse). The model also requires that virgin females be pubertally mature before they will progress to sexual intercourse. Adequate fits were obtained to the intercourse prevalences for both black and white respondents. Comparisons of alternative models established that the full model was superior to models that omitted either the nonepidemic process or the requirement of females' pubertal maturation. The model was able to fit both white and blacks simultaneously, assuming equal transition probabilities in both races. Hence, we propose the hypothesis that race differences in sexual intercourse prevalence may be strongly influenced by the age of initiation of the "epidemic" process and by race difference in females' rates of pubertal maturation. The results suggested that most new cases of sexual intercourse arose from the epidemic process and that males were more prone to progress to intercourse, given an opportunity.

Adolescent↗
PubMedDate not supplied

A social contagion model of adolescent sexual behavior: explaining race differences.

Black adolescents in the United States consistently report an earlier age of first intercourse than White adolescents. Purely psychosocial explanations of this finding have been less than successful. We propose an "epidemic" model that combines social contagion (a psychosocial process) and pubertal maturation (a biological process). This epidemic model permits social contacts among adolescents of the same age and also among younger and older adolescents. The model statistically fit the actual growth curve of sexuality well for Whites; its fit was not as good for Blacks. From computer simulation analyses, we concluded that pubertal maturation may be more important in accounting for the racial difference in the onset of sexual intercourse than previously thought.

Adolescent↗
PubMedDate not supplied

Genetic and environmental influences on vocabulary IQ: parental education level as moderator.

This article examines how parental education level moderates the genetic and environmental contributions to variation in verbal IQ. Data are from 1909 non-Hispanic Whites and African American sibling pairs from the National Longitudinal Study of Adolescent Health, which obtained nationally-based samples of identical (MZ) twins, fraternal (DZ) twins, full and half siblings, cousins (in the same household), and biologically unrelated siblings. In the whole sample, the variance estimate for heritability (h2 = .57, SE = .08) was greater than that for shared environment (c2 = .13, SE = .04). Both heritability and the shared environmental estimate were moderated, however, by level of parental education. Specifically, among more highly educated families, the average h2 = .74 (SE = .10) and the average c2 = .00 (SE = .05). Conversely, among less well-educated families, heritability decreased and shared environmental influences increased, yielding similar proportions of variance explained by genetic and environmental factors, average h2 = .26 (SE = .15), and average c2 = .23 (SE = .07).

Adolescent↗
PubMedDate not supplied

Behavior problems among children from different family structures: the influence of genetic self-selection.

To examine both genetic and environmental influences on children's behavior problems in households defined by marital status and sibling relatedness, this study applied behavioral genetic methodology to four groups totalling 1524 sibling pairs drawn from 796 households: (1) two-parent full siblings, (2) two-parent half siblings, (3) mother-only full siblings, and (4) mother-only half siblings. Model-fitting procedures found that within-group variation on four subscales from the Behavior Problems Index was best explained by a model including both genetic and shared environmental factors. This model was then fit to the behavior problems means of the four groups. Its successful fit to these mean structures suggested that mean-level differences between groups were explained with the same influences that accounted for within-group variation. Genetic influences accounted for 81% to 94% of the mean-level difference in behavior problems between the two-parent, full sibling and the mother-only, half sibling groups. In contrast, shared environmental influences accounted for 67% to 88% of the mean-level difference in behavior problems between the two-parent, full sibling and mother-only, full sibling groups. The genetic influences are interpreted in terms of genetic self-selection into family structures.

Adolescent↗