Retention in the NIDA Clinical Trials Network Women and Trauma Study: Implications for Post-trial Implementation

Background & Purpose

Retention in clinical trials of racial and ethnic minority women is lower than Caucasian women and all males. Attrition hampers researchers' ability to address health disparities, and it prevents generalizable conclusions about the efficacy of tested interventions. Retention in clinical trials and in treatment, especially of substance-dependent women with histories of trauma, is a challenge. This study aimed to identify factors that influenced treatment retention in the NIDA-funded Women and Trauma Study (WTS), conducted within the Clinical Trials Network. Identified factors can then be modified to enhance retention in both trials and treatment in community settings.

Methods

Women (n = 346) were recruited from and received treatment in 6 community-based substance abuse treatment sites. The sample was 46% White; 34% African American; 14% biracial and multiracial; and 7% Latina. All participants met diagnostic criteria for a substance use disorder and posttraumatic stress disorder. In addition to treatment-as-usual, participants were randomized to receive 12 group sessions over six weeks of Seeking Safety (an integrated trauma and substance abuse psychotherapy) or Women's Health Education (a health focused psychoeducational attention control). To better reflect community practice, groups were implemented using an open, rolling admission format. Both treatment groups were facilitated by clinicians working within the treatment programs. Log-linear and logistic models were used to explore factors associated with treatment retention, including site differences, demographics, substance use, trauma severity, therapeutic alliance, and other service utilization.

Results

The mean number of sessions attended was 6.8 (SD = 3.9). No significant demographic differences between the women in the control and experimental arms, or differences in their rates of retention, were identified. Women with more education, higher attendance at 12-step meetings, and strong therapeutic alliance between facilitator and participant had better retention. Significant site differences were found such that the site with the highest retention rate provided child care, did not offer trauma-informed substance abuse treatment, and had the lowest average monthly intake.

Conclusions & Implications

A moderate to high level of retention can be achieved with women who have histories of both trauma and substance use. 12-step programs may act as a source of support, helping women to stay the course of substance abuse treatment. Training staff in the skills necessary to establish strong therapeutic alliance and encourage 12-step meeting attendance may help increase retention. Perhaps more crucial for post-trial implementation of effective treatments were the differences found in retention by site. The unmet need addressed by the WTS in sites that did not already offer some type of trauma informed service may have contributed to the increase in treatment retention. Smaller programs might offer a more personal treatment environment that may be preferable to women with trauma histories.

Many factors not assessed by this study may have also facilitated women's retention, including social support, legal and family pressures, and employment demands and ought to be tested in future studies. Knowing that rates of retention varied across diverse treatment sites, modifying site-related variables will be crucial for retaining women in “real world” settings.