PTCDA on Cu(111) partially covered with NaCl.

The organic molecule 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) was studied by means of scanning tunneling microscopy (STM) on thin insulating NaCl films grown on a Cu(111) single crystal. The deposition of approximately two monolayers (ML) of sodium chloride onto a Cu(111) substrate at a sample temperature of about 350 K causes a rather rough growth of (100)-oriented NaCl islands up to a local height of 4 ML. For submonolayer coverages (0.1 and 0.4 ML) of PTCDA on a Cu(111) surface partly covered with NaCl, two different rod structures of PTCDA were found on the copper surface, which are in contrast to previously published data for PTCDA on Cu(111) showing a herringbone-like arrangement. These findings can be explained by the formation of a Na(x)-PTCDA complex. On NaCl covered areas, single PTCDA molecules adsorb at vacancies of [010] and [001] oriented steps of the NaCl(100) islands. In this case, the electrostatic forces between the polar step edges and the PTCDA molecules are dominant. The terraces of the alkali halide surface are free of PTCDA molecules.

Monthly variations in self-reports of alcohol consumption.

OBJECTIVE: This study examines monthly variation in reports of recent alcohol consumption behavior. METHOD: Telephone survey data collected by the Behavioral Risk Factor Surveillance System were used to measure self-reports of drinking and heavy episodic drinking in the 30 days before the interview. The sample (N = 57,758) comprised cases collected in six states in 5 selected years. Monthly variability in self-reported alcohol consumption was evaluated by logistic regression analysis, using "deviation from means coding" for the month of interview, with background variables and year of interview controlled and state-level clustering adjusted. RESULTS: Adults were significantly more likely to report past 30-day alcohol consumption when interviewed during the month of January and less likely to report consumption when interviewed during March. Respondents were also more likely to report heavy episodic drinking during the month of July. Despite large differences in alcohol consumption between male and female participants, these seasonal patterns were essentially the same for both genders. CONCLUSIONS: The findings suggest that assessments of alcohol consumption that do not consider seasonal variation may be biased. In order to minimize this bias, it is recommended that researchers avoid collecting data only during these particular times of the year or extend the data collection interval and control for seasonal variability.

Multiwave analysis of retest artifact in the National Longitudinal Survey of Youth drug use.

We examined follow-up data from surveys in 1988, 1992 and 1994 in order to estimate the prevalence and explore the correlates of retest artifact (denial) of drug use among National Longitudinal Survey of Youth respondents who disclosed lifetime cocaine or marijuana use in 1984. In the cocaine use cohort, 42% denied lifetime cocaine use during at least one follow-up wave. In the marijuana use cohort, about 29% denied lifetime marijuana use during at least one follow-up wave. Denial either leveled off (cocaine) or diminished (marijuana) between the second and third follow-up interviews. The most consistent predictors of denial in both longitudinal and cross-sectional models and across substances were race/ethnicity (black informants had increased rates of denial) and marital status (married respondents had increased rates of denial). Other predictors of denial included interviewer characteristics (social attribution), interview mode, and drug salience. The findings with respect to marijuana reporting trends parallel increased willingness of public officials to retrospectively disclose this behavior in the popular press.

Trends in inhalant use among high school students in Illinois: 1993-1995.

Data were analyzed from two years (1993 and 1995) of a statewide survey of high school students on drug use. Changes in the rates of inhalant use, and associations between inhalant use and sociodemographic variables, were examined across the two survey years. Measures of inhalant use included lifetime use, past year use, and past month use. Analyses showed no significant difference in the rates of inhalant use across years. Associations with sex, ethnicity, and age were partly consistent with previous research findings. Both lifetime and recent inhalant use were more prevalent among males than females. Blacks were less likely to use inhalants (lifetime and recent) than other racial/ethnic groups in both survey years. Native Americans showed elevated rates of recent inhalant use in 1993, but not in 1995. While age trends in the 1993 survey were consistent with expectations, age trends in the 1995 survey were not. Recent inhalant use was constant across age groups in the 1995 sample. Also contrary to expectations, inhalant use was not more prevalent in low-income or high-poverty areas. The associations of inhalant use with family intactness and academic performance varied by race/ethnicity. Family intactness was a significant protective factor only for whites and Hispanics. Poor grades were not a significant predictor of lifetime inhalant use for blacks, and the protective effect of high grades was found only for whites. Poor grades were highly predictive of lifetime inhalant use for Asians.

Decreased drug reporting in a cross-sectional student drug use survey.

PURPOSE: Prior longitudinal cohort studies have suggested that reinterviews about drug use often lead to decreased reports of lifetime substance use (recanting). Respondents may edit their answers on reinterview because of perceptions regarding question threat. Since reinterviews usually occur after long periods of time, the influence of inadequate recall (memory), cannot be ruled out. In order to evaluate the relative importance of editing and memory on recanting, we examined a cross-sectional survey administered in 1993 to a probability sample of Illinois students who were in the 7th through 12th grade. METHODS: Two sets of self-administered survey questions assessed drug use: the I-SAY drug-use questionnaire, and a supplemental questionnaire asked at the end of the main survey. We compared the rates of "new use" (no use for a drug reported in the I-SAY, use reported for a drug on the supplement) with rates of recanting (use for a drug reported on the I-SAY, no use for a drug reported on the supplement). RESULTS: Recanting was generally more pronounced than new use, especially for cocaine, heroin, marijuana, and inhalants. Those classified as light or inconsistent users on the I-SAY were significantly more likely to recant their drug use reports.

Can self-reported drug use data be used to assess sex risk behavior in adolescents?

To better understand and control the spread of sexually transmitted diseases among high-risk youth, we must first acquire reliable reports of sexual risk behavior. This study evaluates one potential method for validating such reports. We examined the association between marijuana and cocaine use reporting patterns and the number of reported recent sexual partners in a sample of juvenile arrestees/detainees. Using urinalysis to validate self-reported drug use, we categorized drug use reporting patterns into four groups: overreporters, underreporters, honest users, and honest nonusers. Analyses showed, in general, that overreporters reported more sexual partners than either underreporters or accurate reporters, suggesting that overreporters of drug use may also exaggerate sex partner reports. Findings suggest a new method for validating self-reported sexual behavior and provide a challenge to theories of juvenile delinquency.

A mass-distributed CD-ROM for school-based suicide prevention.

Recent violent events in schools in the United States have underscored the need for an examination of efforts aimed at mass education of school professionals on issues related to violence prevention and crisis intervention. A CD-ROM ("Team Up to Save Lives: What Your School Should Know About Preventing Youth Suicide") was mass mailed to schools throughout the United States in January 1997. We conducted an initial evaluation of this intervention in the Chicago area and found that the scope of the CD's impact was relatively narrow: Only 39% of all schools with informants that were contacted actually reviewed the CD-ROM and provided feed back for the evaluation. Insufficient time, computer equipment, and training were the major obstacles to CD-ROM use and to participation in the evaluation. Among those reviewing the CD-ROM, overall perceptions regarding its utility were extremely favorable. Multiple instances in which the CD had been used to address actual crisis situations were identified.

Inhalant use and delinquent behavior among adolescents: a comparison of inhalant users and other drug users.

AIMS: To evaluate the association between inhalant use and delinquent or criminal behavior. DESIGN: A large statewide sample of high school students participated in a survey on drug use. Five groups were identified based on reported drug use: inhalant experimenters, other drug experimenters, inhalant users, other drug users and non-users. Inhalant users were compared with other drug users and inhalant experimenters with other drug experimenters on three measures of problem behavior. PARTICIPANTS: Over 13,000 students in grades 7-12 participated in the 1993 survey on drug use. MEASUREMENTS: Three measures of problem behavior: drinking and drug-taking, "trouble behavior" and minor criminal activity. FINDINGS: Among upper (9-12) grade level students only, both inhalant users and inhalant experimenters reported more minor criminal activity than other drug users and other drug experimenters, respectively. A similar trend was noted for trouble behavior. The same was not found for drinking and drug-taking behavior. CONCLUSIONS: The findings suggest that inhalant use is categorically different from other drug use, and that it has more in common with general delinquency than with general drug use. Prevention and treatment strategies should take this into consideration.

Validity of drug use reporting in a high-risk community sample: a comparison of cocaine and heroin survey reports with hair tests.

Hair specimens were collected from 322 subjects and analyzed as part of an experimental study administering household surveys during 1997 to a high-risk community sample of adults from Chicago, Illinois. Toxicologic results were compared with survey responses about recent and lifetime drug use. About 35% of the sample tested positive for cocaine, and 4% tested positive for heroin. Sample prevalence estimates of cocaine use based on toxicologic results were nearly five times the survey-based estimates of past month use and nearly four times the survey-based estimates of past year use. With the hair test results as the standard, cocaine and heroin use were considerably underreported in the survey. Underreporting was more of a problem for cocaine than for heroin. Among those who tested positive, survey disclosure of cocaine use was associated with higher levels of cocaine detected in hair. In general, when recent drug use was reported, it was usually detected in hair. When a drug was detected in hair, use was usually not reported in the survey. When heroin was detected in hair, cocaine was almost always detected as well.

Sexual harassment and generalized workplace abuse among university employees: prevalence and mental health correlates.

OBJECTIVES: This study hypothesized that interpersonal workplace stressors involving sexual harassment and generalized workplace abuse are highly prevalent and significantly linked with mental health outcomes including symptomatic distress, the use and abuse of alcohol, and other drug use. METHODS: Employees in 4 university occupational groups (faculty, student, clerical, and service workers; n = 2492) were surveyed by means of a mailed self-report instrument. Cross-tabular and ordinary least squares and logistic regression analyses examined the prevalence of harassment and abuse and their association with mental health status. RESULTS: The data show high rates of harassment and abuse. Among faculty, females were subjected to higher rates; among clerical and service workers, males were subjected to higher rates. Male and female clerical and service workers experienced higher levels of particularly severe mistreatment. Generalized abuse was more prevalent than harassment for all groups. Both harassment and abuse were significantly linked to most mental health outcomes for men and women. CONCLUSIONS: Interpersonally abusive workplace dynamics constitute a significant public health problem that merits increased intervention and prevention strategies.

Accuracy of parent mental health service reporting: results from a reverse record-check study.

OBJECTIVE: To examine the feasibility of conducting a reverse record-check study to validate parent reporting on child mental health service use and to examine the accuracy of parent reports of child mental health services. METHOD: Information about child service use was abstracted from medical records and subsequently compared with reports provided by caregivers in telephone interviews. A sample of children using outpatient psychiatric services was compared with a sample of children using outpatient orthopaedic services. Rates and correlates of successful caregiver tracking and of service use reporting accuracy were explored. RESULTS: Caregivers of nearly 30% of all index children were contacted and interviewed. Parent reports of lifetime mental health service use were more accurate than reports of lifetime receipt of orthopaedic services. Elapsed time between survey interview and last treatment episode was negatively associated with reporting accuracy. Number of clinic visits was positively associated with reporting accuracy. Preliminary findings suggested that questions about mental health services may be considered sensitive by parents whose children use them. CONCLUSIONS: Reverse record-check studies based on telephone interviews are potentially problematic with a sample drawn from a large, inner-city medical center. Findings suggest that memory difficulties may be a more important correlate of reporting accuracy than response editing (social desirability). Potential discomfort with disclosure of mental health service use does not result in service use underreporting.

A longitudinal assessment of teacher perceptions of parent involvement in children's education and school performance.

This study examines the ways in which parental involvement in children's education changes over time and how it relates to children's social and academic functioning in school. Teachers provided information on parent involvement and school performance for 1,205 urban, kindergarten through third-grade children for 3 consecutive years. They rated the following four dimensions of parent involvement: frequency of parent-teacher contact, quality of the parent-teacher interactions, participation in educational activities at home, and participation in school activities. As predicted, the frequency of parent-teacher contacts, quality of parent-teacher interactions, and parent participation at school declined from Years 1 to 3. Every parent involvement variable correlated moderately with school performance and parent involvement in Years 1 and 2, and accounted for a small, but significant amount of variance in Year 3 performance after controlling for initial performance level. Participation in educational activities at home predicted the widest range of performance variables. Results suggest that enhancing parental involvement in children's schooling relates to improvements in school functioning.

Implementing means restriction education in urban EDs.

This study evaluated the impact of a mail information campaign on emergency department (ED) professionals' knowledge about the lethal role of firearms in suicide, knowledge of appropriate strategies for warning caregivers of adolescents who have attempted suicide about firearms, and practices with respect to the delivery of such warnings. Responses obtained from physicians and nurses working in ED sites within the targeted city (Chicago) were compared with responses from ED professionals employed in a comparison city (Detroit). In Chicago, the percentage of respondents recommending firearm removal strategies increased from 60% at pretest to 76% at posttest. Individual reports of caregiver warnings per adolescent suicide exposure showed a significant decline in Chicago and a marginally significant decline in Detroit. Gains in knowledge about firearm warning strategies persisted in multivariate analyses controlling for subject demographic characteristics. The pattern of results suggests that the intervention may have effected changes in knowledge while having little impact on behavior. More intensive, interactive educational strategies may be needed to effect behavioral changes among ED professionals.

Sequence of drug use among serious drug users: typical vs atypical progression.

Sequence of drug use was examined in a secondary analysis of two samples of serious drug users: one of 152 men and one of 133 women. The proportions of drug users following specified patterns of drug use onset were compared to proportions obtained in previous research in samples of high school youth, and serious drug users. The serious drug users were substantially different from high school samples in their progression of drug use. The serious drug users were less likely to follow the typical sequence identified in previous studies (alcohol, then marijuana, followed by other illicit drugs). They were more likely to have used marijuana before using alcohol, and more likely to have used other illicit drugs before using marijuana. We also found that atypical sequencing was associated with earlier initiation of the use of illicit drugs other than marijuana and greater lifetime drug involvement. These findings suggest that for a large number of serious drug users, marijuana does not play the role of a 'gateway drug'. We conclude that prevention efforts which focus on alcohol and marijuana may be of limited effectiveness for youth who are at risk for serious drug abuse.

Childhood abuse and the use of inhalants: differences by degree of use.

OBJECTIVES: Using two existing ethnographic studies of drug-involved adults, this study evaluates the association between child-abuse victimization and levels of involvement in inhalant use. METHODS: Historical accounts of childhood exposure to physical or sexual abuse were compared among nonusers of inhalants (n = 197), light inhalant users (n = 64), and heavy inhalant users (n = 24). Crude and adjusted odds ratios were used to compare informants with no history of inhalant use with those having a history of light inhalant use and those having a history of heavy inhalant use. RESULTS: Heavy inhalant use was associated with history of any child abuse (adjusted odds ratio [OR] = 4.6) and physical abuse (adjusted OR = 3.8). Light inhalant use showed no association with child-abuse history. CONCLUSIONS: Child abuse may be an important correlate of extensive involvement in inhalant use. The findings invite speculation with respect to a hypothetical causal role for child abuse in the etiology of inhalant use. The lack of support for causality in this study underscores the need for replication and more carefully designed longitudinal research.

The reliability and consistency of drug reporting in ethnographic samples.

Findings are addressed concerning the reliability of reporting on drug dealing and drug use. Reports provided in retrospective life history interviews are compared with reports gathered and summarized from eight prospective weekly interviews. Most subjects reporting involvement in drug dealing during the weekly interviews, also reported involvement in this behavior during the life history report. There was a tendency for subjects to deny current involvement in drug dealing during the life history reports, even though they reported involvement in drug dealing in the weekly interviews. Binary indicators derived from life history interviews about current drug use were consistent with reports provided prospectively. Subjects reported considerably higher use quantities and frequencies for substances in the life history reports than they did in the weekly interview reports. These results are examined in the context of other recent work examining the reliability of retrospective substance involvement reports. Implications for ethnographic research on drug use are discussed.

Children's ability to delay gratification: longitudinal relations to mother-child attachment.

Concurrent and longitudinal mother-child attachment qualities were studied in relation to children's ability to postpone gratification at age 6 years. A sample of 32 children (at ages 12 months and 18 months) and their mothers participated in the strange situation procedure. At age 6 years, they were observed in an attachment situation and administered a standard delay of gratification task. The length of time that children were able to delay gratification at age 6 was predicted both by concurrent attachment quality and by a longitudinal attachment measure. Children with secure attachment were able to wait the longest periods of time, whereas those with insecure-disorganized attachment had the most difficulties in waiting. The effects of longitudinal, but not concurrent, attachment quality on children's total waiting time remained significant when other important variables were considered, including gender and children's cognitive functioning. An interactive effect was found between attachment quality and cognitive functioning. Insecure-avoidantly attached children with high cognitive functioning did not differ in their overall waiting times from securely attached children, but insecure-avoidantly attached children with average or low cognitive functioning did have shorter waiting times. The study provides a basis for the further investigation of mother-child attachment quality as a factor that is linked to children's delay behavior.

The applicability of the theory of planned behavior to abusive men's cessation of violent behavior.

This study examined the ability of Ajzen's (1988; 1991) Theory of Planned Behavior (TPB) to explain men's cessation of violent behavior. TPB suggests that a man's intention to abuse his female partner, and therefore his subsequent abusive behavior will be determined by: (1) his evaluation of possible outcomes of abusive behavior (attitudes toward behavior); (2) his perception of the expectations of others around him concerning violence and (3) the degree to which he believes he can control his abusive behavior. Pretest self-report measures from men and follow-up recidivism data based on partner report were available for 176 cases drawn from a previous study conducted by Harrell (1991). Reliable proxy measures for TPB variables (intentions/expectations to use violence, attitudes toward behavior, social norms, perceived behavioral control) were created. Regression analyses testing the TPB model provided modest support for prediction of intention to reabuse and subsequent abusive behavior. Of the TPB variables, perceived control appeared to be most important in understanding batterers' intentions to abuse and their subsequent abusive behavior. Refinement in measurements and the need for additional modifications to the model are discussed.

Assessment of knowledge gains in proactive training for postvention.

This paper describes the development of a knowledge measure for the evaluation of a proactive training program for suicide postvention and analyses of its psychometric properties. The 25-item true-false knowledge test was administered before and after each of 12 training sessions; a total of 205 school personnel participated in the training and evaluation. Participants showed significant improvement in overall test scores and on several individual items following the training. Analyses suggested that the measure has construct validity, and that it taps a single underlying dimension. Strengths and weaknesses of the measure, and measurement issues in program evaluation are discussed.

Substance involvement among juvenile murderers: comparisons with older offenders based on interviews with prison inmates.

We evaluated substance involvement among incarcerated juvenile offenders convicted of murder of manslaughter. Patterns of substance involvement among juvenile offenders were compared with patterns found in older offenders. Irrespective of age group, close to one-third of all homicide perpetrators reported that they were affected by alcohol prior to the offense. In every age group, alcohol was the substance showing the highest rate of "regular" lifetime use and the highest rate of ingestion in the week preceding the homicide. In many respects, the reported substance use patterns in the 16-17-year-old age group were closer to the patterns demonstrated by the oldest (36+) age group than they were to the adjacent 18-20-year-old group. Juvenile offenders were generally less substance involved than all but the oldest group of offenders. Almost all of the juveniles who were substance involved prior to the homicide attributed the homicide to the effects of those substances. Narrative accounts suggest that substances (almost always alcohol) escalated impulsive, spontaneous violent outbursts. Implications for the interpretation of self-reports about substance use provided by murderers are also discussed.