US National Sample Research Articles

Mental disorders and subsequent educational attainment in a US national sample

As part of a larger investigation of the adverse effects of mental disorders on role functioning, we examined the associations of early-onset mental disorders with subsequent educational attainment in a large nationally representative survey of the US adult population. Diagnoses and age of onset for each of 17 DSM-IV disorders were assessed through retrospective self-report with the fully structured WHO Composite International Diagnostic Instrument (CIDI). Survival analysis was used to examine the associations between early-onset DSM-IV/CIDI disorders and subsequent termination of schooling with controls for socio-demographic characteristics and childhood adversities (i.e. childhood traumatic events, childhood neglect, parental mental illness, family disruption, and low parental educational attainment). Mental disorders were found to be significantly associated with termination of schooling prior to completion of each of four educational milestones (primary school graduation, high school graduation, college entry, college graduation), with odds ratios in the range of 1.3–7.0. The proportion of school terminations attributable to mental disorders was largest for high school graduation (10.2%) but also meaningful for primary school graduation (3.8%), college entry (4.4%) and college graduation (2.6%). These results add to a growing body of evidence documenting a wide variety of adverse life course effects of mental disorders.

Children with Autism: Quality of Life and Parental Concerns

Past research has shown that children with autism and their families have compromised quality of life (QOL) in several domains. This study examined QOL and parental concerns in children with autism during early childhood, childhood, and adolescence compared to children with Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder (ADD/ADHD) and to typical controls from a US national sample. Families with children diagnosed with autism reported more profound QOL effects than families of children with ADD/ADHD or unaffected controls. Children with autism were significantly less likely to attend religious services, more likely to miss school, and less likely to participate in organized activities. Parental concerns over learning difficulty, being bullied, stress-coping, and achievement were overwhelming in the autism group relative to the comparison groups.

Factors associated with treatment nonadherence among US bipolar disorder patients

Since sustained treatment-adherence is often problematic and may limit clinical outcomes among bipolar disorder (BPD) patients, we sought risk factors to guide clinical prediction of nonadherence. Data were from a 2005 US national sample providing questionnaire responses by 131 randomly selected prescribing psychiatrists and their adult BPD patients. We contrasted demographic and clinical factors in treatment-adherent versus nonadherent patients (strictly defined as missing > or =1 dose within 10 days) in univariate analyses followed by multivariate logistic-regression modeling. Of 429 DSM-IV BPD patients (79% type-I; 62% women; 17% minorities), 34% reported missing > or = 1 dose of psychotropic medication within 10 days, 20% missed entire daily doses at least once, and only 2.5% missed all doses for 10 days. However, their prescribing psychiatrists considered only 6% as treatment-nonadherent. Factors significantly associated with nonadherence in multivariate modeling ranked: alcohol-dependence > youth > greater affective morbidity > various side effects > or = comorbid obsessive-compulsive disorder > or = recovering from mania-hypomania. Unrelated were sex, diagnostic subtype, and other comorbidities. Since most patients received > or = 2 psychotropics, potential relationships between treatment-complexity and adherence were obscured. Prevalent treatment-nonadherence among American BPD patients, and striking underestimation of the problem by prescribing clinicians may encourage increasingly complex treatment-regimens of untested value, but added expense, risk of adverse effects, and uncertain impact on treatment-adherence itself.

Maternal Depressive Symptoms, Father's Involvement, and the Trajectories of Child Problem Behaviors in a US National Sample

To examine the effect of maternal depressive symptoms on child problem behavior trajectories and how the father's positive involvement may modify this association. Secondary data analysis using data from the National Longitudinal Survey of Youth. A nationally representative household sample of men and women from the National Longitudinal Survey of Youth. The study sample includes 6552 mother-child dyads interviewed biennially between January 1, 1992, and December 31, 2002; children were 0 to 10 years old at baseline. Intervention Past-week maternal depressive symptoms in 1992. Maternal self-reports of child internalizing and externalizing behaviors were assessed repeatedly using a modified Child Behavior Checklist. Linear growth curve models indicate that the adverse effects of maternal depressive symptoms on child problem behavior trajectories become negligible after controlling for the father's involvement and other covariates, including the child's age, sex, and race/ethnicity; the mother's educational level; maternal age at child birth; number of children; poverty status; urban residence; and father's residential status. Positive involvement by the father was inversely associated with child problem behavior trajectories. The effects of maternal depressive symptoms on child problem behaviors varied by the level of the father's positive involvement. When the father actively compensates for limitations in the depressed mother's functioning, the child's risk of problem behaviors may be reduced.

Gender Differences in the Relationship of Puberty with Adolescents’ Depressive Symptoms: Do Body Perceptions Matter?

This study explored how pubertal status is related to depressive symptoms among adolescent boys and girls and whether body perceptions explained this relationship. This study is based on a national random US sample of adolescents from the National Longitudinal Study of Adolescent Health (9,011 girls and 8,781 boys). Results showed that boys and girls responded differently to puberty. During the transition to puberty boys had higher depressive symptoms than post-pubertal boys, due to perceptions that they were not as physically large and developed as their peers. Pre-pubertal and post-pubertal boys did not significantly differ on depressive symptoms. Post-pubertal girls had higher depressive symptoms than pre-pubertal girls, due to perceptions that they were overweight and more physically developed than their peers.

Diagnosis and Management of Food-Induced Anaphylaxis: A National Survey of Pediatricians

Food allergy is a common pediatric problem, affecting as many as 6% of young children, yet it is unclear whether pediatricians are well prepared to manage food-induced anaphylaxis. The purpose of this work was to assess pediatricians' knowledge of diagnosis and management of children with food-induced anaphylaxis. A survey designed to assess food allergy diagnosis and management was mailed to a US national random sample of 1130 pediatricians. Survey questions were based on a clinical scenario involving a child having an anaphylactic reaction after ingesting peanut. Primary outcome measures included correct responses to the 11 questions about anaphylaxis. A total of 468 pediatricians (41%) responded to the survey. The majority of the respondents were women (58%), spent > 50% of their time in a clinical setting (78%), and reported providing care for food allergy patients (86%). Overall, 70% of the pediatricians agreed that the clinical scenario was consistent with anaphylaxis, and 72% chose to administer epinephrine. However, only 56% of respondents agreed with both the diagnosis of anaphylaxis and treating with epinephrine. Most pediatricians (70%) did not recognize that a 30-minute observation period after anaphylaxis was too short. Pediatricians who reported providing care for food allergy patients were more likely to agree with the diagnosis of anaphylaxis (73% vs 59%), with treating the reaction with epinephrine (73% vs 64%), and with prescribing self-injectable epinephrine (83% vs 66%) than pediatricians who did not care for food allergy patients. The more certain that pediatricians were that the child was having an anaphylactic reaction, the more likely they were to agree with treating the reaction with epinephrine. In general, recent continuing medical education was not predictive of improved knowledge. Although the majority of pediatricians seem to have some knowledge of food-induced anaphylaxis, a substantial proportion has knowledge deficits that may hinder their ability to provide optimal care to children with food-induced anaphylaxis. Pediatricians who provide health care for patients with food allergy may be better equipped to manage food-induced anaphylaxis than those who do not. Because continuing medical education was not a significant predictor of increased knowledge, ensuring that pediatric residents develop experience managing patients with food allergies may be a better strategy to educate primary care pediatricians about food allergy.

The need for substance abuse after-care: Longitudinal analysis of Oxford House

Aims There is a need to explore the processes of social support and self-efficacy change over time among individuals in recovery homes, and to assess the extent to which residents remain abstinent, obtain and maintain employment, refrain from criminal activity, and utilize health care systems both while within the and after leaving such settings. Design Residents were recruited and interviewed at an initial baseline phase and then re-interviewed at three subsequent 4-month intervals. Setting Oxford Houses are recovery home residences for individuals with substance abuse and dependence problems who seek a supportive, democratic, mutual-help setting. Participants A national US sample of Oxford House residents ( n = 897: 604 men, 293 women). Measurements Information was gathered on abstinence, social support, self-efficacy, employment, criminal history, and medical care utilization. Findings Change in cumulative abstinence was predicted by support for alcohol use, abstinence self-efficacy, and length of residency in OH (i.e., less than versus ≥ 6 months), even after controlling for initial time spent in OH. Conclusions Results suggest that receiving abstinence support, guidance, and information from recovery home members committed to the goal of long-term sobriety may enhance residents' abstinence self-efficacy and enable persons recovering from alcohol and other drug addiction to reduce the probability of a relapse.

Student Competence in Understanding the Matter Concept and Its Implications for Science Curriculum Standards

Using the US national sample from the 1995 Third International Mathematics and Science Study (TIMSS), this study examined students' competence levels in understanding the matter concept at grades 3, 4, 7, 8 and high school graduation, and compared them to the expectations in the US national science education standards. It was found that third‐grade students were developing understanding on mixtures, and fourth‐grade students were developing understanding on separating mixtures; seventh‐ and eighth‐grade students were only at the beginning level of differentiating chemical properties from physical properties; they were not ready for the particulate model of chemical change. High school physical science specialization students were still at the developing level of understanding kinetic and atomic models of chemical and physical changes; they may not be able to master those theories. The findings suggest that the Benchmarks for Science Literacy and Atlas for Science Literacy may have overestimated the competences of elementary, middle school, and high school students.

E‐shopping lovers and fearful conservatives: a market segmentation analysis

PurposeTo classify internet users into holiday shopper and non‐shopper segments, and to profile the demographic, psychographic, and computer use characteristics of each segment.Design/methodology/approachSelf‐report data come from a national US sample of online internet users. Segments are customer revealed using traditional cluster analysis. Lifestyle measures are reduced to higher order measures using factor analysis. Profiles are analyzed via descriptive statistics, graphs, and radar charts.FindingsSix important segments are identified in the data. Three of the segments characterize customers who resist online shopping, even though they engage in other online activities. Security fears and technological incompetence typically inhibit these users from engaging in electronic exchange. Some internet users simply choose not to shop online. Three of the segments describe active e‐shoppers who are driven by a unique desire to socialize, minimize inconvenience, and maximize value.Research limitations/implicationsData come from self‐report questionnaires administered and collected electronically through the internet. Focus is placed on holiday gift buying. Since, holiday shopping is very important to e‐retailers, results are managerially interesting, but might not be indicative of other shopping periods.Practical implicationsTo be successful, e‐retailers must understand those things that motivate and inhibit customer online shopping. Marketing activities targeted at reticent e‐shoppers should focus on benefits, guarantee safeguards and facilitate technical literacy. Service, value, and online ambiance should be carefully tailored to meet the desires and expectations of each customer type.Originality/valueThe study is a replication and extension of earlier online studies which are summarized in the reviewed literature.

Correlates of physical activity in a national sample of children aged 9–13 years

Background. Physical activity (PA) is critical for children's normal growth and development. The purpose of this study was to assess potential correlates of physical activity in a US national sample of youth aged 9–13 years. Methods. A nationally representative telephone survey of parent–child pairs was conducted from April through June 2002. The questions assessed organized and free-time physical activity behavior and psychosocial and environmental variables that are potentially related to youth physical activity. Results. Children's positive outcome expectations or beliefs about the benefits of participating in physical activity and parent's beliefs that participating in physical activity is important were related to participation in both organized and free-time physical activity. Children's perception of parental support and parent's reports of direct support were strongly related to organized physical activity. Feeling safe, having lots of places to be active, and parental participation with their child were strongly related to free-time physical activity. Conclusions. Messages and interventions aiming to increase children and adolescent's participation in organized and free-time physical activity should continue to focus on promoting the benefits that are associated with being active, the importance of parental support, and the provision of safe and enjoyable opportunities to be active.

Use of complementary and alternative medicine practitioners by people with physical disabilities: Estimates from a National US Survey

Purpose. To estimate the prevalence of complementary and alternative medicine (CAM) practitioner use, assess the reasons for use, and determine the symptoms for which CAM practitioners were consulted in a national US sample of insured adults with physical disabilities.Methods. Data for this study come from a longitudinal survey conducted in 2000 and 2001 on a national sample of 830 adults with health insurance who had one of four disabling conditions: multiple sclerosis, cerebral palsy, spinal cord injury, and arthritis. Estimates of annual prevalence and reasons and symptoms for which CAM practitioners were consulted are derived from cross-sectional analysis of the 2001 survey data. Prior use of CAM was assessed using the 2000 survey.Results. CAM practitioners were consulted by 19% of the sample, a rate similar to, or higher than the general population. CAM use was more prevalent among women than men (24 vs. 10%), in the Western US (30%) compared to the Midwest (20%) Northeast (14%), and South (10%) and among prior users (62%) compared to non-users (8%). There were no significant differences in CAM use by condition, although individuals with spinal cord injury reported the lowest use (14%). Common symptoms treated were pain (80%), decreased functioning (43%), and lack of energy (24%). Common reasons for using CAM practitioners included lifestyle choice (67%) and because they are perceived to be more effective than conventional medicine (44%).Conclusions. Evidence from the current survey suggests that a significant proportion of people with physical disabilities consult CAM practitioners. Many of those who use CAM do so because it fits their lifestyle and because they perceive it to be more effective than conventional medicine for treating common symptoms including pain and decreased functioning.

Can Patients with Alcohol Use Disorders Return to Social Drinking? Yes, So What Should We Do about It?

Polemics on the issue of whether people with alcohol use disorders can learn to moderate their alcohol use have existed for decades (1). On one side of the debate are advocates of the disease, or 12-step, model of alcohol problems, who argue that individuals suffering from the disease will inevitably lose control of their use if exposed to any amount of alcohol. According to this model, abstinence is the only way to arrest the disease's development. From the alternative perspective, several related arguments are mounted. Some proponents argue that folks require different strokes-that different types of alcohol problems require different types of responses, such as abstinence for some problems and moderated drinking for other types. Other clinicians focus on the benefits of adopting a harm-reduction orientation toward alcohol problems. This approach focuses less on the amount of alcohol consumed and more on helping individuals decrease the harms related to alcohol use. Although abstinence may be desirable, it is not the primary measure of successful outcome. In this paper, I briefly review the arguments supporting the feasibility of nonabstinent drinking outcomes and argue further that we should shift the debate from whether nonabstinent goals are feasible to how we can best integrate such a perspective into our treatment systems. If we expand the range of our treatment options, we may encourage more people with alcohol use disorders to seek treatment. Finally, I discuss what interventions are appropriate to incorporate in this expansion, if we accept that nonabstinence goals are appropriate for some people. Several lines of evidence point to the validity of nonabstinence treatment goals for some people with alcohol use problems. First, as early as the 1940s, follow-up studies of individuals suffering from alcoholism have revealed that a proportion of patients, albeit a small group, describe successful and sustained nonabstinence outcomes (2). The most widely cited of these studies is the Rand report from the mid-1980s, which followed up a large US national sample of patients from abstinence-oriented inpatient alcohol treatment programs. Remarkably, about 18% of these patients were described as drinking in a problem-free fashion after 4 years (3). A second line of evidence comes from treatment evaluation studies that have included nonabstinent drinking goals. Amborgne recently reviewed these studies (2) and identified 12 that consistently found that some patients were able to sustain posttreatment nonproblem drinking over follow-up periods ranging from 1 to 8 years. Several patient characteristics are found to predict successful nonabstinent outcomes. These include younger age, relatively better social and psychological stability, being employed, being female, and having less severe alcohol dependence (4), as well as having a stronger belief in one's ability to moderate drinking (5). Several medical factors, including pregnancy and liver disease, preclude a nonabstinent goal. Why, then, have our treatment systems not fully embraced these data and promoted interventions that allow nonabstinent outcome goals? The diverse political and economic barriers to system change have been discussed elsewhere (6) and are not limited to the substance abuse field. However, one relevant factor is, of course, the experience and intuition of individual clinicians. As clinicians, we are uncomfortable with incorrectly predicting an individual's outcome. Unfortunately, none of the patient characteristics that predict successful moderation are robust enough to be used by clinicians planning individual patient treatment. Rather, a probabilistic model fits-the more indictors present in an individual, the more likely it is that the goal is appropriate. Even so, the prediction is not perfect: a particular patient with all the right indicators for successful moderation (for example, a younger, socially and psychologically stable woman with a mild alcohol problem) might better quit than cut back on her drinking. …

Students' progression of understanding the matter concept from elementary to high school

Using the US national sample from the Third International Mathematics and Science Study (TIMSS) and the Rasch modeling method, this study identified the conceptual progression sequence of various matter concept aspects, and compared students' latent abilities against the sequence. We found that the four matter aspects, i.e. conservation, physical properties and change, chemical properties and change, and structure and composition, are interrelated. Although they differ in overall difficulty with an increased difficulty from conservation to physical properties and change to chemical properties and change and to structure and composition, the difference among them is not statistically significant at the 0.05 level. Elementary school students (3rd and 4th grades) have an average latent ability below the average difficulty of items on the conservation aspect; 7th graders' average latent ability is above the average difficulty level of the conservation and physical properties and change aspects; 8th and 12th grade students' average latent ability is above the average difficulty level of all the aspects except for structure and composition; and 12th grade science specialization students' average latent ability is above the average difficulty level of all the four aspects. We proposed a dynamic overlapping wave model of matter concept development to make sense the above-identified progression patterns. © 2005 Wiley Periodicals, Inc. Sci Ed89:433–450, 2005

Developmental growth in students' concept of energy: Analysis of selected items from the TIMSS database

AbstractThe aim of this study was to develop a model of students' energy concept development. Applying Case's (1985, 1992) structural theory of cognitive development, we hypothesized that students' concept of energy undergoes a series of transitions, corresponding to systematic increases in working memory capacity. The US national sample from the Third International Mathematics and Science Study (TIMSS) database was used to test our hypothesis. Items relevant to the energy concept in the TIMSS test booklets for three populations were identified. Item difficulty from Rasch modeling was used to test the hypothesized developmental sequence, and percentage of students' correct responses was used to test the correspondence between students' age/grade level and level of the energy concepts. The analysis supported our hypothesized sequence of energy concept development and suggested mixed effects of maturation and schooling on energy concept development. Further, the results suggest that curriculum and instruction design take into consideration the developmental progression of students' concept of energy. © 2005 Wiley Periodicals, Inc.

Alcohol Use Disorders Among US College Students and Their Non–College-Attending Peers

Heavy/binge drinking among college students has become a major public health problem. There is consistent evidence suggesting that young adults in college are drinking more than their non-college-attending peers, but it is still not clear whether they are more likely to suffer from clinically significant alcohol use disorders. To compare the prevalence of alcohol use disorders and alcohol use disorder symptoms in college-attending young adults with their non-college-attending peers within the same study in a large and representative US national sample. Cross-sectional survey. Civilian, noninstitutionalized US population. Young adults (n = 6352) from the 2001 National Household Survey on Drug Abuse (19-21 years of age, 51% female, 66% white, 14% African American, 14% Hispanic). Lifetime, past-year, and past-month drinking, past-year and past-month weekly drinking, past-month weekly binge drinking, past-month daily drinking, typical quantity consumed in the past month, and past-year DSM-IV alcohol dependence and abuse diagnoses. Eighteen percent of US college students (24% of men, 13% of women) suffered from clinically significant alcohol-related problems in the past year, compared with 15% of their non-college-attending peers (22% of men, 9% of women; overall odds ratio = 1.32). The association between past-year alcohol use disorder and college attendance was stronger among women (odds ratio = 1.70) than men (odds ratio = 1.14). College students were more likely to receive a diagnosis of DSM-IV alcohol abuse than their peers not attending college; despite the fact that those in college were drinking more, they were not more likely to receive a diagnosis of DSM-IV alcohol dependence. College students suffer from some clinically significant consequences of their heavy/binge drinking, but they do not appear to be at greater risk than their non-college-attending peers for the more pervasive syndrome of problems that is characteristic of alcohol dependence.

Age at puberty and father absence in a national probability sample

The relations between intactness of the parental unit (e.g., father absent at age 14) and pubertal timing in both men and women were examined in a US national probability sample. In both men and women, an absent father at age 14 predicted an earlier age of puberty (e.g., early menarche or voice change). There was little evidence that an absent mother or the presence of a stepfather, independent of a father's absence, was related to early puberty in either men or women. The results extend previous research and suggest that certain psychosocial factors (i.e., father absence) may affect growth and development in both adolescent girls and boys.

Mapping the SF-12 to the EuroQol EQ-5D Index in a national US sample.

Preference scores for the Medical Outcomes Study (MOS) SF-12 would enable its use in cost-effectiveness analyses. Previous mapping studies of MOS instruments top reference-based instruments have not examined performance in national samples. 15,000 adults in the 2000 Medical Expenditure Panel Survey annual survey including the SF-12 and EQ-5D Index. Regression of the EQ-5D Index scores onto the physical and mental component summary scores of the SF-12, testing 2nd-4th degree polynomial and spline models, including and excluding sociodemographics. A 2nd degree polynomial model explained 63% of the variance in EQ-5D scores, with robust internal and external validation. More complex mod-els explained minimally additional variance. Compared with EQ-5D valuations, prediction models overestimated the lowest health states (6% of the population). The mapped SF-12 yields usable preference-scaled scores, with some caution for the lowest health states.

Panic disorder and pain in a national sample of persons living with HIV

Research to date has focused on depression and co-existing pain in HIV with relatively little attention devoted to the study of anxiety disorders and concurrent pain. We therefore examined the relationships among panic disorder, posttraumatic stress disorder (PTSD), major depression and pain in a US national sample of persons with HIV, controlling for key sociodemographic and clinical variables, including HIV disease status. The study sample comprised 1489 HIV+ individuals (representing 219 667 persons). In multivariate analyses, panic disorder showed a strong association with pain ( β=−15.70; 99% confidence interval [CI]=−21.33 to −10.08; P<0.001), which was significantly greater than PTSD ( P=0.002) but only marginally greater than major depression ( P=0.02). Longitudinal analyses of the three psychological disorders revealed that increasing pain from baseline to follow-up (an approximately 6-month period) was associated with panic disorder only (relative risk ratio=2.18, 99% CI=1.02–4.69; P<0.01), after controlling for baseline pain scores, baseline HIV disease status and change in disease stage across time. We discuss specific mechanisms by which clinical anxiety and chronic pain may be mutually maintained in HIV+ individuals. Our findings suggest that panic disorder, as well as PTSD and major depression are associated with greater pain in HIV patients.

Correlates of serum lipoprotein (A) in children and adolescents in the United States. The third National Health Nutrition and Examination Survey (NHANES-III)

ObjectiveTo determine the correlates of serum lipoprotein (a) (Lp(a)) in children and adolescents in the United States.MethodsCross-sectional study using representative data from a US national sample for persons aged 4–19 years participating in The Third National Health Nutrition and Examination Survey (NHANES-III).ResultsWe observed ethnicity-related differences in levels of Lp(a) > 30 mg/dl, with values being markedly higher in African American (black) than nonhispanic white (white) and Mexican American children in multivariate model (P < 0.001). Higher levels of Lp(a) > 30 mg/dl associated with parental history of body mass index and residence in metro compared to nonmetro in Blacks, and high birth weight in Mexican American children in the NHANES-III. In the entire group, total cholesterol (which included Lp(a)) and parental history of premature heart attack/angina before age 50 (P < 0.02) showed consistent, independent, positive association with Lp(a). In subgroup analysis, this association was only evident in white (P = 0.04) and black (P = 0.05) children. However, no such collective consistent associations of Lp(a) were found with age, gender, or birth weight.ConclusionEthnicity-related differences in mean Lp(a) exist among children and adolescents in the United States and parental history of premature heart attack/angina significantly associated with levels of Lp(a) in children. Further research on the associations of Lp(a) levels in childhood with subsequent risk of atherosclerosis is needed.

Most smokeless tobacco use is not a causal gateway to cigarettes: using order of product use to evaluate causation in a national US sample

To evaluate non-causal and causal patterns of smokeless tobacco (SLT) and cigarette use; to assess the prevalence of 'non-gateway' and possible 'gateway' patterns of SLT use. Data from the Cancer Control Supplement to the 1987 National Health Interview Survey, a representative survey of non-institutionalized adults in the United States. From reported age at first use, participants were categorized by type and sequence of tobacco product use. SUDAAN 8.0.1 was used for statistical analyses. Males aged 18-34 (n = 3454), weighted to provide estimates of the US population. A subsample of males aged 23-34 (n = 2614) was analyzed to minimize the possibility of future product switching. Smoking status, smokeless tobacco (snuff, chewing tobacco, both) use status, age at regular use of cigarettes, age at first use of smokeless tobacco. Of those 23-34-year-olds who had ever used SLT with or without cigarettes, 77.2% (95% CI: 71.3, 83.3) were classifiable as non-gateway users in that 35.0% (95% CI: 29.9, 40.1) had only used SLT and 42.2% (95% CI: 36.8, 47.7) had used cigarettes first. Cigarette use in younger cohorts was less common, despite increased SLT use. Those who used cigarettes before moist snuff were 2.1 times more likely to have quit smoking (95% CI 1.21,6.39) than cigarette-only users. The large majority of SLT users are non-gateway users. Causal gateway effects should be of minor concern for policy. SLT may be more likely to prevent smoking than cause it.