Stage 1- prior to observing the video
This experiment was conducted in a laboratory located within a Health Centre. Participants sat in a chair at a table with a computer arranged on their left-hand side and the TV screen directly in front of them. Prior to meeting the participants, the experimenter had counterbalanced the order of presentation of the videos and the grounding technique by alternating the video and condition presentation for each participant number. Those who received the grounding technique first were allocated to condition one, those receiving it second, condition two. Hence, participant one received condition one and video one, participant two condition two and video two, participant three condition one and video two and so forth.
1. All participants read the participant information sheet and were given an opportunity to ask questions.
2. The informed consent form was signed by both experimenter and participant. Participants who had a mental health problem, or who had been diagnosed with one in the past were excluded at this stage.
For those receiving the grounding technique first, the experimenter said:
‘ ‘On the tray in front o f you are a variety o f coloured pieces o f Plasticine, pick the one you fin d most attractive, and would most like to touch (Participant then indicated
a colour).
While you are watching the video I would like you to alternate making small pyramid
(experimenter demonstrated) and small cube shapes (experimenter demonstrated).
Please begin with a pyramid. Once you have made one I would like you to put it in the
tub on the right. Then make a square and place it in the left-hand tub. Use the
Plasticine to make as many shapes as you can and continue throughout the whole
duration o f the video. The reason fo r doing this is that people often fin d it reassuring
to be manipulating an object when they are feeling stressed.
Be careful to ensure that you are looking at the video while you are making the
shapes. You do not need to look at the tubs, as they are very different heights; the one on the right fo r the pyramids, is much taller than the one fo r the squares on the left
Go ahead — try it out \
4. The participant was then observed making shapes whilst looking at the screen. When the experimenter was satisfied that they could perform the task, the experiment continued.
The experimenter then said:
You will now be asked to complete some questions on the computer screen. After
which, you will see the fdm. Remember to pick up your Plasticine and start making
shapes as soon as the film starts. The computer will warn you to do this ju st prior to
the film starting. You stop making shapes when the film ends.
Then you will be asked to complete some more questions on the computer. There are a
lot o f questions to answer so try to give the first response that come to mind and
answer as swiftly as possible without rushing. You cannot change answers or go
backwards. Inform the experimenter at the end o f any mistakes i f necessary. Do not
look around the room. I am only outside the door, and will be checking things are
progressing smoothly by using this peephole (experimenter points to keyhole). You
can stop at any point and ring the bell to get the experimenter. This section should
take about 25 minutes in total”
For those participants in condition two the experimenter instructed the participant in the same way as the boxed text directly above, ignoring the highlighted text pertaining to Plasticine.
5. The experimenter set the computer program to start. The lights were turned off and the participant left alone in the room.
6. The experimenter sat outside the door in case the participant called for them.
Stage 2 - computer administered questionnaires and video
The following questionnaires were presented on the computer. □ Trait Dissociation Questionnaire (TDQ).
□ State dissociation questionnaire (DSS). □ Personal relevance of car crashes. □ First Mood ratings (all ten).
All participants then watched the first video either with or without the grounding task depending on whether they had been allocated to Condition l o r 2.
Stage 3 - After the video
Participants then completed the following questionnaires and ratings on the computer
□ State dissociation questionnaire (DSS). □ 2"^ Mood ratings (all ten).
□ Attention paid to film rating. □ Distress caused by film rating. □ Attention paid to task rating.
1. The experimenter then re-entered the room and asked the participant to complete the PDEQ on paper.
2. Participants then watched the second video and then repeated stage three. They were assigned to a new task which they had not completed previously, i.e. if they completed watching the video with the grounding task they then watched the video without the grounding task and vice versa.
3. The experimenter explained how to complete the seven-day diary, stressing that it was really important in terms of developing an understanding of clinical intrusions
that they complete it at least daily. The experimenter also ensured that the participant understood the difference between an intrusive image and a thought. 4. An appointment was made for the follow-up in seven days time. The
experimenter’s contact phone number was written on the diary, and the participant was encouraged to contact the experimenter if they felt distressed during the week.
Stage 4 - Follow up
The following week, these measures were presented to the participant in the order in which they appear below. They were all completed by hand.
• Diary compliance rating
• Cued Recall Memory and Recognition Memory Tests
• The seven-day diary was used to identify the most significant intrusion (please see above for description)
• Intrusion Description Questionnaire. • Prediction of experimental hypotheses.
The participants were then debriefed and given opportunity to ask any questions they had about the study.