Guide
SUDs and VOC are the two ratings taken in EMDR reprocessing. SUDs, Subjective Units of Disturbance, asks how disturbing the target feels right now, from 0 (none, neutral) to 10 (the worst imaginable). VOC, Validity of Cognition, asks how true the positive cognition feels right now, held with the target, from 1 (completely false) to 7 (completely true). Both are first taken in the assessment phase. SUDs is checked through desensitization until it reaches 0, and VOC through installation until it reaches 7, unless another number is ecologically valid.
| SUDs | VOC | |
|---|---|---|
| Stands for | Subjective Units of Disturbance | Validity of Cognition |
| Measures | How disturbing the target feels now | How true the positive cognition feels now, held with the target |
| Range | 0 (no disturbance, neutral) to 10 (the worst disturbance imaginable) | 1 (completely false) to 7 (completely true) |
| Asked as | A felt rating of the present moment, not of how bad the event was | A gut-level felt sense, not an intellectual judgment |
| Comes from | Joseph Wolpe’s behavior therapy, where it ran 0–100 | Francine Shapiro’s first EMDR study (1989) |
| First taken | Assessment (phase 3), after the emotions are named | Assessment (phase 3), right after the positive cognition |
| Taken again | At the end of each channel in desensitization (phase 4), and on recall in reevaluation (phase 8) | Through installation (phase 5) |
| Finished at | 0, or 1 when that is ecologically valid | 7, or 6 when that is ecologically valid |
The question is about now. Clients often rate how bad the event was, which does not change, instead of how disturbing it feels to bring it up today, which is what reprocessing works on. If a rating seems stuck from the first set, check which question the client is answering.
SUDs can rise during desensitization as new material surfaces. A reading is a snapshot of that moment, not a verdict on the session. It is usually checked when a channel of association seems to have run its course, by returning to the target, rather than after every set, so processing is not interrupted.
The VOC is taken with the target held in mind, and asks for the felt sense of the words rather than what the client thinks ought to be true. A low rating at the start is expected. During installation, check that the positive cognition still fits; if the client has found better words, take the VOC for the new ones.
Shapiro’s protocol rates the VOC from 1 to 7, and that is the scale this site uses. Some clinicians rate both scales 0 to 10 for simplicity. Whichever you use, write the scale beside the number: a VOC of 6 means something different on each.
A rating is ecologically valid when it fits the client’s real situation. A SUDs of 1 may be right for a loss that is still sad, or a danger that is still real; a VOC of 6 may be right when a fully true positive cognition would not be true to the situation.
Ask what keeps the rating from 0, or from 7. If the answer is a blocking belief, it can be processed. If it reflects reality, record the number as ecologically valid, with the client’s reason.
For each reading, record the target, the phase, the number, the scale and when it was taken. Charted across sessions, one target reads like this:
| When | Phase | SUDs (0–10) | VOC (1–7) |
|---|---|---|---|
| Session 4, start | Assessment (baseline) | 8 | 2 |
| Session 4, end | Closure, incomplete | 5 | — |
| Session 5, start | Reevaluation, on recall | 4 | — |
| Session 5, mid | Desensitization, end of target | 0 | — |
| Session 5, late | Installation | — | 5 → 6 → 7 |
| Session 5, end | Body scan clear; closure, complete | 0 | 7 |
| Session 6, start | Reevaluation, on recall | 0 | — |
Two habits keep a chart honest. Never average readings across targets: each target has its own baseline. And keep the incomplete sessions in the chart, because the session where SUDs went from 8 to 5 and stopped is as much a part of the record as the one where it reached 0.
That is how the scale was designed in the original EMDR research, and the standard protocol still uses it. Some clinicians use 0 to 10 for both ratings. Either can be recorded consistently, as long as the scale is written beside each number.
Yes. As new material surfaces, disturbance can rise before it falls. A single reading is a snapshot of that moment, not a verdict on the session.
Usually when a channel of association seems to have run its course, by returning to the target, rather than after every set, so processing is not interrupted.
That is the standard ending, unless another number is ecologically valid for the client’s situation. When it is, record the number and the reason.
Both are in use for the Subjective Units of Disturbance scale. This site writes SUDs throughout.
intuitiveEMDR records each SUDs and VOC reading with its target and phase as you take it in session, and charts every target’s trajectory across sessions. There is a free plan: no credit card, no time limit.
Create a free accountThis page is educational material for trained clinicians. It is not a treatment, does not diagnose anything, and is not a substitute for EMDR training, consultation or care from a qualified professional. If you are in crisis, contact your local emergency services.