EMDR FORUM ARCHIVE, 2000
Lytle Study - Not Just the Abstract
Sandra Paulsen Inobe, PhD · 10/24/02 at 1:46 PM ET
Thanks to a colleague on the other side of the globe who got me a copy of the Lytle article. I have time between clients to post a few quick comments. First, this study has many strengths. It uses well established measures such as the Impact of Event Scale (original, not revised), the STAI, the Beck Depression Inventory, and others. They made efforts to ensure practitioners were well trained at the time (which is over a decade ago, in 1990, when this doctoral dissertation research was conducted). They used sophisticated statistical procedures (ANOVA), and tried to sort out confounding factors (ANCOVA) and appropriate subtests, as near as I can tell. It's great that its a dismantling study. That's why its quite frustrating that within this otherwise careful attempt there are a couple of serious design problems, and few possible other problems that I noticed off the bat. 1. The statistical power just isn't where it needs to be. There are only 15 people in each group. 2. Especially given that a non-clinical sample was used, which the authors admit is a potential problem, we may not see sufficient movement in pre and post measures due to the fact that the scores may not have been high enough to begin with. On the IES, a mean score is reported of 56.58 which is above the 85th percentile for the total group. However, I don't have information on the scatter of those scores, so I don't know how many are subclinical. One subject was excluded because her IES was 0, so I don't know how many had subclinical scores. The authors acknowledge that the results may have been different if the clinical presentation had been more severe or had the subjects been seeking treatment. 1 3. As another poster (I think Ulrich Lanius) noted above, a fixed eye condition may not be different from an eye movement condition, because of the small saccades that are demonstrated to occur in fixed eye conditions. That is, the eyes are actually moving, blurring the distinction between the experiemental and control condition. 4. The biggest and most frustrating problem is this. Why did the editors think that a study utilizing a dosage of 1 hour only of EMD is an appropriate unit of EMDR treatment? This is not a test of EMDR, in which 90 minute sessions are recommended in order to increase the likelihood of getting the symptom relief in a single session. When 90 minutes sessions aren't possible, multiple sessions may be necessary. This is a truncated dosage. In the context of an otherwise careful approach, it is especially concerning, because naive readers will read it and not realize it is an insufficient dosage. This deviation from the usual protocol is not small but large, and I would love to know if the treatment manual that Dr. Shapiro approved and which the first writer apparently wrote described a single 60 minute EMDR session as appropriate treatment. I doubt it - even if that approval occurred a decade ago. The authors list the datedness of their procedure to be a limitation of the study as well. 5. A curiosity to me is the use of a breathing focus task. Although it was included as a measurement method to sample self reported intrusive thoughts, I believe it may have introduced a confounding factor into the treatment conditions. Participants reclined, thought about their stressful event, closed their eyes, and were instructed to imagine and think about this event for 2 min, after which they attended to their breathing for 10 minutes. At one minute intervals, they recorded their mental content. This may be an exposure method. This confounding treatment (or potentially reactive assessment method) occurred across all conditions. There was a main effect observed using ANOVA on repeated measures of the breathing focus tasks. In the author's final paragraph, they note that emotional processing may have a deleterious effect on subject's level of worry, because both exposure conditions (EMD and Fixed Eye conditions). I offer another interpretation: any exposure treatment that does not allow for a sufficient dosage that treatment is complete can be construed as re-traumatizing. Future studies should use only sufficient dosages of EMDR, not truncated dosages, both for scientific and ethical reasons.
6. In the EMD condition, if the SUD level did not achieve a level of 1 or 2 after 60 minutes, the treatment was truncated. Note that the SUD scale used was a 7 point Likert scale (1-7), rather than the 11 point (0-10) scale used in EMDR, so a level of 1 or 2 on a 7 point scale is somewhat different than on an 11 point scale. We do not know how many subjects had their EMD session truncated at this point, without the installation procedure that marks the end of a completed EMDR treatment. Only those who achieved a SUD 1 or 2 (which is, again, higher than the target level using a 11 point SUD scale, got the installation procedure, described here as a "locking in" procedure. So we don't know how many people got the minimum dosage of EMDR and how many didn't.
---Next client has arrived, must close.
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