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Biomedical subjects

M D Newcomb

Publications and source records attributed to M D Newcomb.

At least 73 records · Page 4Linked to original sources
PubMed1986

Depression, self-derogation, substance use, and suicide ideation: lack of purpose in life as a mediational factor.

A theoretical model of adolescent behavior is examined separately for males and females (N = 722). The model hypothesizes that depression and self-derogation may lead to a lack of purpose in life, which, in turn, may lead to suicide ideation and substance use. Confirmatory factor analyses and structural equation procedures were used to examine the model, using Bentler's (1984) EQS computer program, which is available from BMDP. For both the men and women, the model adequately accounted for the data although there were some important differences between the sexes. In response to psychic discomfort (i.e., Depression and Self-derogation), men are more apt to turn to drugs and alcohol, whereas women consider suicide. Conversely, the situation changes in response to feelings of meaninglessness or a lack of purpose in life. Here, the females appear to turn to substance use, whereas the males react with thoughts of suicide.

Adult↗
PubMed1986

Drug use, educational aspirations, and work force involvement: the transition from adolescence to young adulthood.

The impact of high school drug use and academic potential on high school outcome (graduate or dropout) and young adult work force involvement, college involvement, and educational aspirations was examined. Frequency of drug use, grade point average, and educational plans were assessed for 479 adolescents while in high school. Four years later this same group of individuals, now in their early 20s, reported their current level of drug use, present life involvement on a variety of measures, and whether they had ever graduated from high school. Results indicate that high school graduation is predicted from a lack of cigarette and hard drug use and the presence of high academic aspirations. Using latent variable causal models, it was found that high school Academic Potential and Drug Use were significantly correlated in a negative direction. Across-time analyses indicate that high school Academic Potential significantly predicted young adult Educational Aspirations, College Involvement, and college attendance. High school Drug Use significantly predicted young adult Drug Use, a lack of College Involvement, and increased Work Force Involvement. These results do not support a psychogenic hypothesis of drug use and academic potential but rather confirm an impaired abilities or general deviance interpretation.

Achievement↗
PubMed1986

Cocaine use among adolescents: longitudinal associations with social context, psychopathology, and use of other substances.

Cocaine use has become a significant personal and social problem among all segments of American society. This study uses longitudinal data obtained over a 5-year period from a sample of 847 adolescents to examine numerous antecedents, consequences, and concomitants of cocaine use. Over the 5-year period, significant increases in actual use and social context of use were evident, with 15% of the 17-19 year-olds reporting they had been "super high or stoned" on cocaine at least once. Path analytic models were used to examine the impact of intentions and social context variables (e.g., peer use) on self-use over time, as well as to study the effects of earlier use of alcohol and cannabis on subsequent use of cocaine. Self-reported use of cocaine was highly predictive of use of many other drug substances. Intent to use cocaine is associated with several personality traits. With one exception, measures of psychopathology were not predictive of, nor influenced by, cocaine use over a 1-year period. However, depression did lead to increased cocaine use over this period of time. Finally, income from salaries and gifts was predictive of current cocaine use to a small but significant degree.

Adolescent↗
PubMed1986

Determinants of sexual and dating behaviors among adolescents.

The study of adolescent sexual development has typically focused on the incidence and age of onset of particular behaviors. Recent developments in the analysis of covariance structures permit more powerful simultaneous tests of the determinants of adolescent sexual behavior. These new methods allow the assessment and evaluation of the interrelatedness between unobserved, latent constructs. Data were obtained from 183 males and 193 females ranging in age from 12 to 18 years old, selected from three birth cohorts using a stratified random sample. Eight latent constructs--Sexual and Dating Involvement, Self-Acceptance, Feminist Sex Role Attitudes, Deviant Social Network, Importance of Dating, Lack of Heterosexual Competence, Sexually Active Social Network, and Stressful Change Events--were hypothesized to explain the variance in 26 observed variables. Several causal models were tested that specified structural relationships among the latent constructs. A theoretically meaningful model was arrived at that linked the eight, error-free factors.

Adolescent↗
PubMed1986

Nuclear attitudes and reactions: associations with depression, drug use, and quality of life.

For 40 years the world has lived with the threat of nuclear war and, recently, with the possibility of nuclear power plant accidents. Although virtually every generation must confront various national or international crises, the threat of nuclear war is unprecedented in its destructive potential. This study is an attempt to assess attitudes and amount of distress associated with the ever-present threat of nuclear war and the possibility of accidents at nuclear power plants. The Nuclear Attitudes Questionnaire (NAQ) consists of 15 items and was administered to 722 young adults who have grown up in the nuclear age. The items were found to reflect four latent factors of nuclear concern, nuclear support, fear of the future, and nuclear denial, all of which in turn represent a second-order construct of nuclear anxiety. Women reported significantly more nuclear concern, less nuclear support, more fear of the future, and less nuclear denial than did men. In latent-variable models, nuclear anxiety was found to be significantly associated with less purpose in life, less life satisfaction, more powerlessness, more depression, and more drug use. It is concluded that the threat of nuclear war and accidents is significantly related to psychological distress and may disturb normal maturational development.

Accidents↗
PubMed1986

Life events and substance use among adolescents: mediating effects of perceived loss of control and meaninglessness in life.

Throughout history, alcohol and other drugs have been used to provide relief in times of stress and frustration. Research has confirmed this association between disruptive life change events and substance use. It was hypothesized that two psychological constructs facilitate and mediate this relation between stress and substance use. Uncontrollable stress (negative life change events) was assumed to create a sense of loss of control, which in turn engendered a decreased level of meaning in life. This meaninglessness in life, experienced as distressful and uncomfortable, is then treated or medicated with various drug substances. This theoretical sequential model was tested in two separate studies with independent samples of adolescents (one sample collected by the Rutgers University and the other collected by the University of California, Los Angeles [UCLA]) using latent variable structural models. The Rutgers sample was cross-sectional, whereas the UCLA sample provided longitudinal data. Results supported the theoretical hypothesis that Perceived Loss of Control and Meaninglessness mediate the relation between Uncontrollable Stress and Substance Use. In the Rutgers data, the association between stress and drug use was clearly accounted for by the mediating constructs; in other words, no direct path was necessary to explain the relation between stress and general drug use. However, in the UCLA data there remained a direct influence of Uncontrollable Stress on Substance Use after accounting for the significant impact of the mediating constructs. Five other competing models were tested; four were rejected empirically, and the other was accepted, although it was less theoretically based than the mediational model.

Adolescent↗
PubMed1986

Substance use and ethnicity: differential impact of peer and adult models.

Modeling of a specific behavior by peers and adults is an important influence on an adolescent's choice to engage in that behavior. This study examined the impact of perceived peer and adult substance use on reported self-use within groups of black, Hispanic, Asian, and white teenagers. Effects were studied for four types of drugs: beer/wine, hard liquor, marijuana, and pills. In general, Asians and blacks reported the least self-use, whites reported the most peer models, and blacks reported the most adult models. Differential patterns of increase in use and perceived use by grade level were found across the four ethnic groups. Overall, perceived peer use of beer/wine, liquor, and marijuana was associated more with self-use than was perceived adult use. For pill use, only whites reported significantly greater influence of peers over adults on their self-use. For all substances, blacks reported the least impact of peer use on self-use relative to the three other groups. In regard to the impact of adult use on self-use, blacks and Hispanics reported the lowest for beer or wine; blacks and Asians reported the lowest for marijuana; and whites reported the highest for pills. These results are discussed in the context of differential vulnerability to modeling and vicarious learning.

Adolescent↗
PubMed1986

Life change events among adolescents. An empirical consideration of some methodological issues.

Recent critiques in the stress literature have identified several methodological shortcomings, including ignoring control over event occurrence, the confounding of life event and outcome measures, the lack of consistent and reliable measures, and few cross-validational studies. Each of these problems is addressed empirically by examining two independent samples of adolescents. A 39-item life event measure, developed previously in one sample of 1018 adolescents, was administered to a second sample of 376 teenagers. Second-order factors of six stress scales were clustered into controllable and uncontrollable events, both of which were related to psychological distress. Poor health was significantly related to an uncontaminated factor of uncontrollable events. Means and covariances of the seven stress factors were compared between the derivation sample and an age-matched subset of the cross-validation sample. Correlates of the scales with drug use and personality revealed interpretable associations within the cross-validation sample and were quite similar to those in the original sample. Finally, few sex differences were evident, whereas scores on controllable events scales increased with age.

Adolescent↗
PubMed1986

Adolescents' substance use: impact of ethnicity, income, and availability.

This study examines ethnic differences in reported use of cigarettes, alcohol, cannabis, hard drugs, and non-prescription medications among a sample of adolescents and attempts to explain these differences in terms of income, ease of acquisition, and availability from friends. Data were obtained from 847 students three times over a five-year period. Results indicate consistent and significant differences among ethnic groups substance use at all three points in time. It was hypothesized that ethnic groups have differential access to substances and economic resources to purchase various drugs. To test these hypotheses, availability from friends, perceived ease of acquisition, income from earnings and gifts/allowances, and initial substance use were examined across ethnic groups and then used as covariates of the substance differences. A split-plot repeated measures design with covariates was used to compare changes in substance use across time and between ethnic groups. Earned income made a significant impact on explaining the ethnic differences for cigarette, alcohol, and given income on cannabis consumption. Adding community variables such as availability from friends, ease of acquisition, and initial drug use not only eliminates the effects of income variables on drug use, but in most cases, the ethnic differences among adolescents as well.

Adolescent↗
PubMed1986

Cocaine use among young adults.

The use of cocaine has become quite prevalent among many segments of society, with increasing public concern and personal difficulties resulting from it. This study examines a large group of young adults to determine how cocaine users differ from nonusers. Fully one-third of the sample had used cocaine in the past six months, with about 5% reporting weekly or more use. Numerous important differences were found between users and nonusers in regard to sociodemographic characteristics, use of other licit and illicit drugs, deviant attitudes and behavior, social context of use, physical health, mental health, and life satisfaction. Differences increased with greater involvement with the drug, to the point where cocaine abusers were strikingly different than nonusers. The largest distinctions were noted in regard to cocaine users having more difficulty in the successful acquisition of adult role responsibilities, greater use of other drugs, engaging in more deviant behaviors, and immersion in a social context conducive to use. Smaller but noteworthy differences revealed that cocaine users had poor physical and emotional health statuses and lowered life satisfaction, compared to nonusers. Finally, several personality traits, and in particular a lack of law abidance, predicted a significant increase in cocaine use from adolescence to young adulthood.

Adult↗
PubMed1986

Risk factors for drug use among adolescents: concurrent and longitudinal analyses.

We examined the concurrent and longitudinal associations between risk factors and substance use for a sample of high school students. Ten risk factors were defined that assessed numerous important personal and social areas of life. These factors were found to be associated with ever using, frequency of use, and heavy use of cigarettes, alcohol, cannabis, and hard drugs. Few effects were noted for nonprescription medication. No sex differences were evident for number of risk factors. Finally, the number of different risk factors was predictive of increases in use of all types of substances over a one-year period, after controlling for initial level of use.

Adolescent↗
PubMed1985

The role of perceived relative parent personality in the development of heterosexuals, homosexuals, and transvestites.

This study examines the hypothesis that non-normative parent sex-role qualities contribute to homosexual and transvestite development. Using the Parent Characteristics Questionnaire (PCQ), this hypothesis was tested among samples of male and female heterosexuals, male and female homosexuals, and male transvestites. The PCQ assesses the relative distribution of five personality traits between mother and father: R-F (relative father) intellectuality, R-F dependence, R-F affiliation, R-F endurance, and R-F aggressive-dominance. No significant differences were noted for the male homosexuals, while the hypothesized effects were evident for lesbian women and male transvestites, even when statiscally controlling for age and education differences. Theoretical interpretations of the results are offered in the context of a nonpathological explanation of sexual orientation and preference.

Adolescent↗
PubMed1984

Sexual behavior, responsiveness, and attitudes among women: a test of two theories.

This study tests two theories regarding the attitude and behavioral determinants of women's coital and masturbatory orgasmic responsiveness. Data from 115 sexually active women were analyzed using latent-variable structural equation models. Twenty-one variables are used to represent seven latent constructs: Parent Sexual Attitudes, Sexual Latency, Sexual Behavior, Dating Competence, Social Assertiveness, Subjective Masturbatory Responsiveness, and Subjective Coital Responsiveness. Two specific theories are tested with these constructs. Each theory predicts a different structural arrangement among these latent factors with the fundamental difference being whether behavior predicts responsiveness or vice-versa. Two alternate models were found to reflect the data adequately. In both instances, attitudes predicted behavior and, in general, orgasmic responsiveness tended to be a function of behavior.

Adolescent↗