Analysis of Covariance in Randomized Experiments with Heterogeneity of Regression and a Random Covariate: The Variance of the Estimated Treatment Effect at Selected Covariate Values.

Researchers detecting heterogeneity of regression in a treatment outcome study including a covariate and random assignment to groups often want to investigate the simple treatment effect at the sample grand mean of the covariate and at points one standard deviation above and below that mean. The estimated variances of the simple treatment effect that have traditionally been used in such tests were derived under the assumption that the covariate values were fixed constants. We derive results appropriate for a two-group experiment that instead presume the covariate is a normally distributed random variable. A simulation study is used to confirm the validity of the analytical results and to compare error estimates and confidence intervals based on these results with those based on assuming a fixed covariate. Discrepancies between estimates for fixed and random covariates of the variability of treatment effects can be substantial. However, in situations where the extent of heterogeneity of regression is like that typically reported, presuming the covariate is random rather than fixed will generally result in only a modest increase in estimated standard errors, and in some circumstances can even result in a smaller estimated standard error. We illustrate the new methods with an empirical data set.

Body dissatisfaction and disordered eating in Native American, Hispanic, and White College Women.

PURPOSE: The sociocultural model of eating disorders asserts that societies which emphasize the thin-ideal have higher rates of body dissatisfaction and disordered eating. Recent research questions the related presumption that non-White cultures value a larger ideal female and thus have lower rates of body dissatisfaction and disordered eating. The limited research on these constructs in racial/ethnic minorities primarily has used non-validated instruments. The current study investigated rates of body dissatisfaction and disordered eating with validated, widely used measures. METHODS: Measures of body dissatisfaction and disordered eating were completed by 896 college women in the United States: 473 Hispanics, 341 non-Hispanic whites, and 82 Native Americans. RESULTS: Although Native Americans and Hispanics had higher body mass indices (and larger ideal shapes) than White women, the groups had similar body dissatisfaction scores. Native Americans reported somewhat less restricted eating compared to White women. When controlling for body mass index and age, group differences on body dissatisfaction emerged and the group differences in eating disorder symptoms became more pronounced, with White women showing more pathology. Reliability and validity across groups were good. CONCLUSIONS: This study offers some support for the sociocultural model of eating disorders and provides mean scores for Native American and Hispanic females on widely-used eating disorder measures. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

Overcoming Addictions, a Web-Based Application, and SMART Recovery, an Online and In-Person Mutual Help Group for Problem Drinkers, Part 2: Six-Month Outcomes of a Randomized Controlled Trial and Qualitative Feedback From Participants.

BACKGROUND: Despite empirical evidence supporting the use of Web-based interventions for problem drinking, much remains unknown about factors that influence their effectiveness. OBJECTIVE: We evaluated the performance of 2 resources for people who want to achieve and maintain abstinence: SMART Recovery (SR) and Overcoming Addictions (OA). OA is a Web application based on SR. We also examined participant and intervention-related factors hypothesized to impact clinical outcomes of Web-based interventions. METHODS: We recruited 189 heavy drinkers through SR's website and in-person meetings throughout the United States. We began by randomly assigning participants to (1) SR meetings alone, (2) OA alone, and (3) OA and SR (OA+SR). Recruitment challenges compelled us to assign participants only to SR (n=86) or OA+SR (n=102). The experimental hypotheses were as follows: (1) Both groups will reduce their drinking and alcohol-related consequences at follow-up compared with their baseline levels, and (2) The OA+SR condition will reduce their drinking and alcohol or drug-related consequences more than the SR only condition. Additionally, we derived 3 groups empirically (SR, OA, and OA+SR) based on the participants' actual use of each intervention and conducted analyses by comparing them. Primary outcome measures included percent days abstinent (PDA), mean drinks per drinking day (DDD), and alcohol or drug-related consequences. Postbaseline assessments were conducted by phone at 3 and 6 months. Secondary analyses explored whether clinical issues (eg, severity of alcohol problems, level of distress, readiness to change) or intervention-related factors (eg, Internet fluency, satisfaction with site) affected outcomes. RESULTS: Both intent-to-treat analyses and the actual-use analyses showed highly significant improvement from baseline to follow-ups for all 3 groups. Mean within-subject effect sizes were large (d>0.8) overall. There was no significant difference between groups in the amount of improvement from baseline to the average of the follow-ups. We found that participants who stopped drinking before joining the clinical trial had significantly better outcomes than participants who were still drinking when they joined the study. Neither Internet fluency nor participants' reported ease of navigating the site had an impact on outcomes. CONCLUSIONS: These results support our first experimental hypothesis but not the second. On average, participants improved on all dependent measures. Both SR and OA helped participants recover from their problem drinking. Web-based interventions can help even those individuals with lengthy histories of heavy drinking to make clinically significant reductions in their consumption and related problems. These interventions work well for individuals in the action stage of change. TRIAL REGISTRATION: Clinicaltrials.gov NCT01389297; https://clinicaltrials.gov/ct2/show/NCT01389297 (Archived by WebCite at http://www.webcitation.org/6kLNUNDcc).

Overcoming Addictions, a Web-based application, and SMART Recovery, an online and in-person mutual help group for problem drinkers, part 1: three-month outcomes of a randomized controlled trial.

BACKGROUND: Overcoming Addictions (OA) is an abstinence-oriented, cognitive behavioral, Web application based on the program of SMART Recovery. SMART Recovery is an organization that has adapted empirically supported treatment strategies for use in a mutual help framework with in-person meetings, online meetings, a forum, and other resources. OBJECTIVE: To evaluate the effectiveness of OA and SMART Recovery (SR) with problem drinkers who were new to SMART Recovery. Our experimental hypotheses were: (1) all groups will reduce their drinking and alcohol/drug-related consequences at follow-up compared to their baseline levels, (2) the OA condition will reduce their drinking and alcohol/drug-related consequences more than the control group (SR), and (3) the OA+SR condition will reduce their drinking and alcohol/drug-related consequences more than the control group (SR only). METHODS: We recruited 189 heavy problem drinkers primarily through SMART Recovery's website and in-person meetings throughout the United States. We randomly assigned participants to (1) OA alone, (2) OA+attend SMART Recovery (SR) meetings (OA+SR), or (3) attend SR only. Baseline and follow-ups were conducted via GoToMeeting sessions with a Research Assistant (RA) and the study participant. We interviewed significant others to corroborate the participant's self-report. Primary outcome measures included percent days abstinent (PDA), mean drinks per drinking day (DDD), and alcohol/drug-related consequences. RESULTS: The intent-to-treat analysis of the 3-month outcomes supported the first hypothesis but not the others. Participants in all groups significantly increased their percent days abstinent from 44% to 72% (P<.001), decreased their mean drinks per drinking day from 8.0 to 4.6 (P<.001), and decreased their alcohol/drug-related problems (P<.001). Actual use relationships were found for the OA groups, between SR online meetings and improvement in PDA (r=.261, P=.033). In addition in the OA groups, the number of total sessions of support (including SR & other meetings, counselor visits) was significantly related to PDA (r=.306, P=012) and amount of improvement in alcohol-related problems (r=.305, P=.012). In the SR only group, the number of face-to-face meetings was significantly related to all three dependent variables, and predicted increased PDA (r=.358, P=.003), fewer mean DDD (r=-.250, P=.039), and fewer alcohol-related problems (r=-.244, P=.045), as well as to the amount of improvement in all three of these variables. Six-month follow-ups have been completed, and the results are currently being analyzed. CONCLUSIONS: These results support our first experimental hypothesis but not the second or third. All groups significantly increased their PDA and decreased both their mean DDD and their alcohol-related problems, which indicates that both interventions being investigated were equally effective in helping people recover from their problem drinking.

Integrating spirituality into alcohol treatment.

Spirituality is presumed by millions of Americans to be directly relevant to problems of alcohol abuse. We summarize findings regarding the role of religion and spirituality in the prevention and treatment of substance abuse and present a case illustration. We also consider mechanisms responsible for these effects. We offer advice about why, by whom, and how religion and spirituality should be discussed with clients with substance use disorders. In a recent clinical trial, therapists trained in a client-centered approach to facilitate exploration of spirituality fostered clients' use of spiritual practices. We suggest that the therapist's ability to skillfully engage clients in a discussion of spirituality is largely determined by how the therapist balances the dual roles of authoritative expert and evocative facilitator.

The test-retest reliability of the Form 90-DWI: an instrument for assessing intoxicated driving.

Although driving while intoxicated (DWI) is a pervasive problem, reliable measures of this behavior have been elusive. In the present study, the Form 90, a widely utilized alcohol and substance use instrument, was adapted for measurement of DWI and related behaviors. Levels of reliability for the adapted instrument, the Form 90-DWI, were tested among a university sample of 60 undergraduate students who had consumed alcohol during the past 90 days. The authors administered the instrument once during an intake interview and again, 7-30 days later, to determine levels of test-retest reliability. Overall, the Form 90-DWI demonstrated high levels of reliability for many general drinking and DWI behaviors. Levels of reliability were lower for riding with an intoxicated driver and for variables involving several behavioral conjunctions, such as seat belt use and the presence of passengers when driving with a blood alcohol concentration above .08. Overall, the Form 90-DWI shows promise as a reliable measure of DWI behavior in research on treatment outcome and prevention.

Preferences for multigene panel testing for hereditary breast cancer risk among ethnically diverse BRCA-uninformative families.

Until recently, genetic testing for hereditary breast cancer has primarily focused on pathogenic variants in the BRCA1 and BRCA2 (BRCA) genes. However, advances in DNA sequencing technologies have made simultaneous testing for multiple genes possible. We examined correlates of interest in multigene panel testing and risk communication preferences in an ethnically diverse sample of women who tested negative for BRCA mutations previously but remain at high risk based on their family history (referred to as "BRCA-uninformative") and their at-risk female family members. Two-hundred and thirteen women with a previous breast cancer diagnosis and a BRCA-uninformative test result and their first-degree relatives completed a survey on interest in multigene panel testing, communication preferences, and sociodemographic, psychological, and clinical factors. Stepwise logistic regression was used to identify factors associated with testing interest. Chi-square analyses were used to test differences in risk communication preferences. Interest in multigene panel testing was high (84%) and did not considerably differ by cancer status or ethnicity. In multivariable analysis, factors significantly associated with interest in genetic testing were having had a mammogram in the past 2 years (odds ratio (OR) = 4.04, 95% confidence interval (CI) 1.80-9.02) and high cancer worry (OR = 3.77, 95% CI 1.34-10.60). Overall, the most commonly preferred genetic communication modes were genetic counselors, oncologists, and print materials. However, non-Hispanic women were more likely than Hispanic women to prefer web-based risk communication (p < 0.001). Hispanic and non-Hispanic women from BRCA-uninformative families have a high level of interest in gene panel testing. Cancer-related emotions and communication preferences should be considered in developing targeted genetic risk communication strategies.

Small-area variations in conviction rates for DWI: the significance of contextual variables in a Southwestern state.

Average annual conviction rates (1990-2000) of people arrested for driving under the influence of alcohol in each of New Mexico's 33 counties are described. Conviction rates vary from 58 to 95%. Rates are correlated with political conservatism, being higher where a higher proportion of voters voted for the republican presidential candidates, and with measures of crowding in the courts. Conviction rates are higher in rural than urban areas and are correlated with a low prevalence of alcohol-related problems in the population. The variance in conviction rates is higher in rural than urban areas, and higher where measures of court crowding are low. The results suggest that political culture and the efficiency of court functioning are each independently associated with conviction rates for DWI and may also be associated in a reciprocal fashion with both low DWI arrest rates and alcohol-involved crash rates.

The Drinker's Check-up: 12-month outcomes of a controlled clinical trial of a stand-alone software program for problem drinkers.

Sixty-one problem drinkers were randomly assigned to either immediate treatment or a 4-week wait-list control group. Treatment consisted of a computer-based brief motivational intervention, the Drinker's Check-up (DCU). Outcomes strongly support the experimental hypotheses and long-term effectiveness of the treatment. Overall, participants reduced the quantity and frequency of drinking by 50%, and had similar reductions in alcohol-related problems that were sustained through 12-month follow-up. The DCU seems to be effective in enhancing problem drinkers' motivation for change.

Variations in jail sentences and the probability of re-arrest for driving while intoxicated.

OBJECTIVE: The probability of re-arrest for driving while intoxicated (DWI) is compared for four different groups of individuals classified by whether the individual was convicted and, if so, the type of sentence received. METHOD: Subsequent re-arrests for DWI were examined for all individuals whose index arrest for DWI had occurred between 1994 and 2001 in a county in New Mexico. The groups included (1) those convicted as a result of the index arrest and sentenced to a 28-day jail/treatment program (N (#)=(#) 2,703); (2) all those not convicted as a result of the index arrest (N = 709); (3) those who were convicted but not sentenced to jail (N = 1,047); and (4) those convicted and sentenced to jail (N = 1,290). RESULTS: Adjusting for covariates of BAC, number of prior arrests, ethnicity, age, and sex, the probability of not being re-arrested was greatest among those sentenced to the jail/treatment program (Group 1), next highest in the two groups convicted but not sentenced to jail/treatment (Groups 3 and 4), and lowest in the group that was not convicted (Group 2). Length of jail sentence among people convicted but not sentenced to the jail/treatment program was unrelated to the probability of re-arrest. CONCLUSION: Conviction for DWI, regardless of the sentence, appears to reduce the probability of re-arrest, and being sentenced to a multi-modal treatment/incarceration program further reduces the probability of re-arrest. However, the other types of sentences do not appear to differ in their impact on probability of re-arrest.

Comparing several robust tests of stochastic equality with ordinally scaled variables and small to moderate sized samples.

In a comparison of 2 treatments, if outcome scores are denoted by X in 1 condition and by Y in the other, stochastic equality is defined as P(X < Y) = P(X > Y). Tests of stochastic equality can be affected by characteristics of the distributions being compared, such as heterogeneity of variance. Thus, various robust tests of stochastic equality have been proposed and are evaluated here using a Monte Carlo study with sample sizes ranging from 10 to 30. Three robust tests are identified that perform well in Type I error rates and power except when extremely skewed data co-occur with very small n. When tests of stochastic equality might be preferred to tests of means is also considered.

The college drinker's check-up: outcomes of two randomized clinical trials of a computer-delivered intervention.

The objective of the study was to evaluate the effectiveness of a computer-delivered intervention (CDI) to reduce heavy drinking and alcohol-related problems in college students in two randomized clinical trials. In Experiment 1, we randomized 144 students to either the CDI or an assessment-only control group with follow-ups at 1 and 12 months. In Experiment 2, we randomized 82 students to either the CDI or a delayed-assessment control group with follow-up at 1 month. In Experiment 1, participants in both groups significantly reduced their drinking at both follow-ups. Compared to the control group, the CDI group reduced their drinking significantly more at 1 and 12 months on three drinking measures at α < .05. Using a more conservative, Bonferroni-adjusted criterion yielded one significant difference in a measure of heavier drinking at the 1 month follow-up. The mean between-groups effect sizes were d = .34 and .36 at 1 and 12 months, respectively. Experiment 2. Compared to the delayed assessment control group, the CDI group significantly reduced (by the Bonferroni-adjusted criterion) their drinking on all consumption measures. These results support the effectiveness of the CDI with heavy drinking college students when used in a clinical setting. In addition, the significant reductions in typical drinking in the control group in Experiment 1 and not in Experiment 2 combined with comparable baseline characteristics suggests that the control group in Experiment 1 demonstrated assessment reactivity.

ModerateDrinking.Com and moderation management: outcomes of a randomized clinical trial with non-dependent problem drinkers.

OBJECTIVE: To evaluate the effectiveness of a web-based protocol, ModerateDrinking.com (MD; www.moderatedrinking.com) combined with use of the online resources of Moderation Management (MM; www.moderation.org) as opposed to the use of the online resources of MM alone. METHOD: We randomly assigned 80 problem drinkers to either the experimental or control group with follow-ups at 3, 6, and 12 months. RESULTS: Seventy-five participants (94%) had outcome data at 1 or more follow-up points, and 59 participants (73%) were assessed at all 3 follow-ups. Comparing baseline measures to the average outcomes at follow-ups indicated a significant overall reduction in both groups in alcohol-related problems and consumption variables. Compared with the control group, the experimental group had better outcomes on percent days abstinent. There was an interaction between intensity of drinking at baseline and treatment in determining outcomes assessing drinking. Less heavy drinkers in the experimental group had better outcomes on log mean blood alcohol content (BAC) per drinking day compared with the control group. Heavier drinkers did not differentially benefit from the MD program on this measure. Mixed model analyses in general corroborated these outcomes. CONCLUSION: The outcome data provide partial evidence for the effectiveness of the MD web application combined with MM, compared with the effectiveness of the resources available online at MM by themselves.

A web application for moderation training: initial results of a randomized clinical trial.

Eighty-four heavy drinkers who responded to a newspaper recruitment advertisement were randomly assigned to receive either (a) training in a Moderate Drinking protocol via an Internet-based program (www.moderatedrinking.com) and use of the online resources of Moderation Management (MM; www.moderation.org) or (b) use of the online resources of MM alone. Follow-ups are being conducted at 3, 6, and 12 months. Results of the recently completed 3-month follow-up (86% follow-up) indicated both groups significantly reduced their drinking based on these variables: standard drinks per week, percent days abstinent, and mean estimated blood alcohol concentration (BAC) per drinking day. Both groups also significantly reduced their alcohol-related problems. Relative to the control group, the experimental group had better outcomes on percent days abstinent and log drinks per drinking day. These short-term outcome data provide evidence for the effectiveness of both the Moderate Drinking Web application and of the resources available online at MM in helping heavy drinkers reduce their drinking and alcohol-related problems.

A randomized trial of a DWI intervention program for first offenders: intervention outcomes and interactions with antisocial personality disorder among a primarily American-Indian sample.

BACKGROUND: Randomized trial evidence on the effectiveness of incarceration and treatment of first-time driving while intoxicated (DWI) offenders who are primarily American Indian has yet to be reported in the literature on DWI prevention. Further, research has confirmed the association of antisocial personality disorder (ASPD) with problems with alcohol including DWI. METHODS: A randomized clinical trial was conducted, in conjunction with 28 days of incarceration, of a treatment program incorporating motivational interviewing principles for first-time DWI offenders. The sample of 305 offenders including 52 diagnosed as ASPD by the Diagnostic Interview Schedule were assessed before assignment to conditions and at 6, 12, and 24 months after discharge. Self-reported frequency of drinking and driving as well as various measures of drinking over the preceding 90 days were available at all assessments for 244 participants. Further, DWI rearrest data for 274 participants were available for analysis. RESULTS: Participants randomized to receive the first offender incarceration and treatment program reported greater reductions in alcohol consumption from baseline levels when compared with participants who were only incarcerated. Antisocial personality disorder participants reported heavier and more frequent drinking but showed significantly greater declines in drinking from intake to posttreatment assessments. Further, the treatment resulted in larger effects relative to the control on ASPD than non-ASPD participants. CONCLUSIONS: Nonconfrontational treatment may significantly enhance outcomes for DWI offenders with ASPD when delivered in an incarcerated setting, and in the present study, such effects were found in a primarily American-Indian sample.