Cognitive Bias Modification for Interpretation (CBM-I) in People with Painful Endometriosis

For this study, we will adopt a double-blind randomized controlled trial methodology, whereby the individuals with endometriosis will be randomly allocated to one of three groups: (1) Cognitive Bias Modification for interpretation (CBM-I) intervention (2) Imagery enhanced CBM-I intervention (3) Placebo control. The intervention for the treatment groups is Cognitive Bias Modification for Interpretation (CBM-I), which aims to train individuals to make benign rather than health-threat related interpretations of ambiguous information. In this intervention, participants will be presented with 27 ambiguous scenarios. These scenarios have been validated in prior research with individuals with a range of pelvic pain related conditions. Each of the scenarios could be resolved with a pelvic pain related or benign solution. Each scenario will be followed by a word fragment that the participant needs to complete. To train participants to make benign interpretations, all word fragments will represent benign, rather than pelvic pain related outcomes. After each scenario, participants will be asked a comprehension question and to indicate whether the question was related to the previous scenario (‘Yes’ or ‘No’). Participants will be given ‘correct’ feedback when they endorse a benign (not pelvic pain-related) response. If participants endorse a pelvic pain-related resolution, they will be given ‘incorrect’ feedback. The CBM-I training itself in terms of the task, training sessions and time and reinforcement of solutions is the same for the two CBM-I conditions. The two CBM-I conditions differ with respect to the pre training practice exercise, the task instructions, and the post scenario fidelity question. These differences are explained below. CBM-I group (CBM-I) Prior to the training, participants in the CBM-I group will receive an introduction to verbal processing and undergo a brief verbal processing training exercise to practice verbal processing (e.g., Holmes et al., 2006; Blackwell et al., 2015). Participants will be presented with sentences about a lemon and asked to focus on the words and meanings of sentences (Holmes et al., 2006). During the CBM-I intervention, these participants will be instructed to pay attention to the words and meanings of the scenarios (Holmes et al., 2006). To assess the degree to which participants focus on words and their meanings throughout the training, after each scenario, participants will also be asked “How difficult was it to understand the meaning of the description?” and will respond on a scale from 1 (not at all difficult) to 5 (extremely difficult) in line with Blackwell et al., (2015) and Holmes et al. (2006). Imagery enhanced CBM-I group (IE_CBM-I) Prior to the training, participants in the IE_CBM-I group will receive an introduction to mental imagery and undergo a brief imagery training exercise to practice generating mental imagery (e.g., Holmes et al., 2006; Blackwell et al., 2015). As per Holmes et al. (2008), participants will be asked to imagine they are cutting a lemon. Details of the mental imagery training are included in the study materials. During the CBM-I trial, these participants will also be instructed to imagine themselves in each scenario, as if actively involved, seeing things through their own eyes (Holmes et al., 2006). To assess the degree to which participants are using imagery throughout the training, after each scenario, participants will also be asked “How vividly could you imagine the scenario described?” and will respond on a scale from 1 (not at all vivid) to 5 (extremely vivid), in line with Blackwell et al., (2015) and Holmes et al. (2006). The intervention will be delivered entirely online by an institutional software program (Qualtrics) that will randomly allocate participants to one of the three groups. There is no direct researcher input.. Participants complete the intervention individually via smartphone or computer. CBM-I will be delivered four times to each participant during the entire study. Time frame: Introduction (5 minutes) + CBM-I training session 1 (10-15 minutes): day 1 of the study Introduction reminder (2 minutes) + CBM-I training session 2 (10-15 minutes): day 8 of the study Introduction reminder (2 minutes) + CBM-I training session 3 (10-15 minutes): day 15 of the study Introduction reminder (2 minutes) + CBM-I training session 4 (10-15 minutes): day 22 of the study The first introduction will take about 5 minutes to complete, the introduction reminders before sessions 2-4 will take 2 minutes, and each of the 4 training sessions will take approximately 10-15 minutes to complete. The number of training sessions completed is recorded for each participant to monitor adherence to the intervention.