15-Month follow up of EMDR treatment for traumatic memory
We previously reported on the outcomes of a controlled study of eye movement desensitization and reprocessing (EMDR) effectiveness in the treatment of traumatic memory (Wilson, Tinker, & Becker, 1994; Wilson, Becker, & tinker, in press). In that study we found that three, 90-minute sessions of EMDR (Shapiro, 1995) "normalized the psychological functioning of the previously traumatized participants (g = 80) on all dependent measures. The present study is a 15-month follow up of those participants. I Method: The research design is shown in Table 1. Participants were randomly assigned to EMDR or to Delayed EMDR conditions. Pretreatment measurement occurred at measurement time TI. Participants in the EMDR condition received EMDR between T1 and T2; those in the Delayed EMDR condition received EMDR between T2 and T3. All participants were tested immediately following treatment and at 3 months following treatment (at T4). The 15 month, long-term follow up occurred at measurement time T5. An independent assessor collected all of the following dependent measures: Subjective Units of Disturbance Scale (SUDS; Wolpe, 1990), Impact of Events Scale (IES; Hmowitz, Wilner, & Alvarez, 1979), State/Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, Lushene, Vagg, & Jacobs, 1983), and the Symptom Checklist (SCL-90-R, Derogatis, 1992). [Table 1. The Research Design, Treatment Condition, Measurement Time: T1 T2 T3 T4 T5; EMDR Treatment: 01 x 02 03 04; Delayed EMDR Treatment 01 02 x 03 04 05; Note: T = Time of measurement; 0 = Observation; X = Treatment administered.] II. Results: Two analyses were performed to assess the impact of EMDR treatment at the 15-month follow up. First, in order to assess the overall, long-term impact of EMDR, the 15-month follow-up scores were compared with the pretreatment scores. There was significant improvement on all nine measures at the 15-month follow up: The multivariate effect was significant (Wilk's Lambda =.11, p<.0005) as were all nine of the univariate effects (all p <.0005). Second, in order to assess whether the improvement shown immediately following EMDR treatment had been maintained over the following year the immediate posttreatment scores were compared with, the 15-month follow-up scores. The multivariate test was nonsignificant (Wilk's lambda=.74, p=.079), indicating the improvement shown immediately following EMDR was maintained 15 months later. The univariate analyses indicated additional improvement for the PTSD symptoms of intrusions (IES Intrusion: F(1,56)=7.71, p=307) and avoidance (IES avoidance: F_(1,56) -4.44, p=.040). None of the nine measures showed deterioration at the 15-month follow up. Prior to EMDR treatment 45% (g= 9) of the responders had been diagnosed as PTSD, at the 15-month follow up only 7% (g = 4) were diagnosed as PTSD (chi-squareo, N=61)= .72, p < .05). III. Responders Versus Nonresponders at the 15-Month Follow up.: At the time of writing this abstract, 75% of the participants (g=61) have responded to the 15-month follow up. In general, measures taken prior to treatment did not differentiate responders fiom nonresponders. Responding at the 15-month follow up was unrelated to age, gender, marital status or years of education, although the annual income of the responders (Mdn=21,500) was higher than that of the nonresponders (Mdn = 14,750, Mann-Whitney U=372.5, p=.017). Responding or not at 15 months was unrelated to the type of trauma experienced, whether or not the participants had been in therapy prior to EMDR treatment, or how long ago the trauma had occurred. It was also unrelated to the severity of the trauma as measured by the pretreatment scores on the nine dependent variables and to whether or not the participant met the PTSD diagnosis criteria prior to treatment. A multiple regression analysis used the immediate posttreatment and 90-day posttreatment scores to predict whether or not the participant responded at the 15-month follow up. Nonrespondents were more likely to be depressed at 90-days following treatment than were respondents (R square=.O8, B=-.16, Beta = -.28, F_L1,71)=5.99, p=.017). No other variables entered into the regression model. IV Discussiona and Conclusion, Tretement effects found immediately following EMDR treatment wer maintained or improved 15 months later and thee was a significant decrease in the number of participants diagnosed as PTSD at the 15 month follow up. The comparison of responders to nonresponders at the 15 month follow up showed that the nonresponders were more depressed than the responders, raising the possiblity that the present results may be favorably biased to some extent. The discussion will include the additional, subjective impressions of participants who did not respond to the follow up. Limitations of EMDR with this population will be discussed, including the influence of comorbidity, multiple traumas, retraumatization after treatment, and spontaneous recurrence of symptoms. V. References: 1) Derogatis, L. R. (1992). SCL-90: Administration Scoring and Procedures Manual II. Baltimore: Clinical Psychometric Research. 2) Horowitz, M. J., Wilmer, N. & Alverez, W. (1979). Impact of Event Scale: A Measure of Subjective Distress. Psychosomatic Medicine, 41, 209-218. 3) Shapiro, F. (1995), Eye Movement Desensitization and Reprocessing: Basic Principles, Protocols, and Procedures. 4) Speilberger, C. D., Gorsuch, R. L., Lushene, R. D., Vagg, P. R., & Jacobs, G. A. (1983). Manual for the State-Trait Anxiety Inventory, Palo Alto: Consulting Psychologists Press. 5) Wilson, S. A., Tinker, R. A., & Becker, L. A. (1994, November). Efficacy of Eye Movement Desensitization and Reprocessing (EMDR)Treatment for Trauma Victims. Paper presented at the Annual Meeting of the International Society for Traumatic Stress Studies, Chicago, IL. 6) Wilson, S. A., Becker, L. A., & Tinker, R. A. (In press), EMDR, treatment for psychologically traumatized individuals, Journal of Consulting and Clinical Psychology.