Obsessive Compulsive Disorder, Trichotillomania
Conditions
Keywords
OCD, Trichotillomania, Response inhibition, Cognitive training
Brief summary
Obsessive-compulsive disorder (OCD) and its related disorders (e.g., trichotillomania) are characterized by the marked difficulty in inhibiting unwanted or inappropriate responses. There is compelling evidence that poor response inhibition is a core cognitive feature of OCD and its related disorders, but no effective intervention exists that directly attempts to address this problematic cognitive deficiency. This study will examine the feasibility and clinical utility of a computerized cognitive training program designed to improve response inhibition among individuals diagnosed with OCD or trichotillomania.This training program offers systematic practice of response inhibition in the form of a 40-level computer game. Individuals with these conditions will be randomized to either 8 sessions of (a) computerized response inhibition training (RIT) or (b) placebo computer training (PLT). We hypothesize that RIT will outperform PLT in improving response inhibition capabilities and reducing relevant clinical symptoms. In sum, this project is expected to generate important knowledge to guide the development of effective computer-based treatment approaches that may help reduce critical problems of existing treatments such as suboptimal patient retention and treatment under-utilization, thereby improving overall treatment response rates among individuals suffering from OCD and related conditions.
Interventions
BEHAVIORALResponse inhibition training
This is a computerized video game that offers 40 training levels, which aims to enhance the individual's response inhibition performance
BEHAVIORALPlacebo Control Training
This placebo control training looks very similar to the response inhibition training program in its appearance. However, it does not offer any practice related to response inhibition capabilities.
Sponsors
National Institute of Mental Health (NIMH)
University of Wisconsin, Milwaukee
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* Principal diagnosis of obsessive-compulsive disorder or trichotillomania
Exclusion criteria
* Current substance use problems * Current/Past Psychotic disorder, bipolar disorder, or schizophrenia * Attention deficit/hyperactivity disorder or tic disorder * Severe depressive symptoms * Current psychotherapy * Current suicidality * Estimated intellectual functioning \< 80 * Lack of response inhibition deficits on a stop-signal task
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Baseline, Week 4, and Week 8 | This is a clinician-administered rating scale of OCD symptom severity, most widely used in treatment outcome research for OCD, and a clinician-administered rating scale of hair pulling symptoms, widely used in clinical trial research for trichotillomania. Given the inclusion of two different diagnostic conditions, the primary outcome for the current study is the z score of the symptom rating severity obtained from the two rating scales, with higher values indicating greater symptom severity. |
| Stop Signal Reaction Time | Baseline, Week 4, and Week 8 | Stop Signal Reaction Time (SSRT; time taken to complete the inhibitory process) is estimated using the tracking algorithm on the computerized stop-signal task, which adjusts the stop signal delay automatically (by 50ms) to maintain the rate of successful inhibition on stop-signal trials at 50%. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Clinical Global Impression Severity and Improvement | Baseline, Week 4, and Week 8 | The Clinical Global Impression Severity and Improvement (CGI) is a clinician-administered rating scale widely used to assess the overall severity of the target condition in treatment outcome research. The CGI is assessed on a 7-point scale, with the severity scale from 1 (Normal, not at all ill) through to 7 (Among the most severely ill patients). Thus, the higher CGI severity rating score indicate a greater level of overall illness. |
| Commission Errors on the Go/No-go Task. | Baseline, Week 4, and Week 8 | The number of commission errors on the go/no-go task is a commonly used measure of response inhibition. In this task, participants are asked to withhold their responses on no-go trials. If they fail to withhold their response in a no-go trial (i.e., pressing the response key to the no-go signal), this response counts toward the total number of commission errors. Therefore, a greater number of commission errors on this task reflects a greater level of inhibitory control deficit. |
Countries
United States
Participant flow
Recruitment details
This study enrolled individuals diagnosed with obsessive-compulsive disorder or trichotillomania at a mid-west university in the United States. The last participant completed in August 2017.
Pre-assignment details
For this study, 258 individuals underwent online pre-screenings, and 83 participated in onsite full eligibility assessments. A total of 45 individuals met the study entry criteria, and were invited to the main study. Of them, 33 participants completed pre-training assessment and randomized into one of the two training conditions.
Participants by arm
| Arm | Count |
|---|---|
| Response Inhibition Training Eight 45-minute sessions of computerized training on response inhibition over a 4 week period
Response inhibition training: This is a computerized video game that offers 40 training levels, which aims to enhance the individual's response inhibition performance | 18 |
| Placebo Control Training Eight 45-minute sessions of computerized placebo control training over a 4 week period
Placebo Control Training: This placebo control training looks very similar to the response inhibition training program in its appearance. However, it does not offer any practice related to response inhibition capabilities. | 15 |
| Total | 33 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 2 | 1 |
Baseline characteristics
| Characteristic | Response Inhibition Training | Placebo Control Training | Total |
|---|---|---|---|
| Age, Continuous | 32.17 years STANDARD_DEVIATION 12.01 | 24.47 years STANDARD_DEVIATION 5.48 | 28.67 years STANDARD_DEVIATION 10.24 |
| Depression Anxiety and Stress - 21 | 27.56 units on a scale STANDARD_DEVIATION 24.08 | 29.73 units on a scale STANDARD_DEVIATION 17 | 28.55 units on a scale STANDARD_DEVIATION 20.88 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 1 Participants | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 18 Participants | 14 Participants | 32 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Obsessive-Compulsive Inventory-Revised | 20.61 units on a scale STANDARD_DEVIATION 16.96 | 19.60 units on a scale STANDARD_DEVIATION 12.57 | 20.15 units on a scale STANDARD_DEVIATION 14.91 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) White | 17 Participants | 14 Participants | 31 Participants |
| Region of Enrollment United States | 18 Participants | 15 Participants | 33 Participants |
| Sex: Female, Male Female | 13 Participants | 13 Participants | 26 Participants |
| Sex: Female, Male Male | 5 Participants | 2 Participants | 7 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 18 | 0 / 15 |
| other Total, other adverse events | 0 / 18 | 0 / 15 |
| serious Total, serious adverse events | 0 / 18 | 0 / 15 |
Outcome results
Primary
Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH)
This is a clinician-administered rating scale of OCD symptom severity, most widely used in treatment outcome research for OCD, and a clinician-administered rating scale of hair pulling symptoms, widely used in clinical trial research for trichotillomania. Given the inclusion of two different diagnostic conditions, the primary outcome for the current study is the z score of the symptom rating severity obtained from the two rating scales, with higher values indicating greater symptom severity.
Time frame: Baseline, Week 4, and Week 8
Population: Intent to treat population (all participants who received at least one session of training with a pre-training assessment). Last observation carried forward (LOCF) imputation method.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Response Inhibition Training | Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Baseline | -.38 z scores | Standard Deviation 1.13 |
| Response Inhibition Training | Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Week 4 | -.89 z scores | Standard Deviation 1.83 |
| Response Inhibition Training | Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Week 8 | -1.20 z scores | Standard Deviation 2.03 |
| Placebo Control Training | Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Baseline | .46 z scores | Standard Deviation 0.51 |
| Placebo Control Training | Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Week 4 | -.52 z scores | Standard Deviation 1.2 |
| Placebo Control Training | Composite Score of Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and National Institute of Mental Health (NIMH) | Week 8 | -.71 z scores | Standard Deviation 1.68 |
Comparison: It was calculated that 30 participants rnadomized in a 1:1 fashion between the 2 arms would have .90 power to detect a large effect (f=.40), but is somewhat underpowered to detect a medium effect (f=.25) between the two groups. Sample size was determined using a repeated-measures ANOVA test (α = .05, a correlation of .5 among repeated measures, and a nonsphericity correction of .6), considering the design effect and potential patient attrition (=25%).p-value: =0.56Mixed Models Analysis
Primary
Stop Signal Reaction Time
Stop Signal Reaction Time (SSRT; time taken to complete the inhibitory process) is estimated using the tracking algorithm on the computerized stop-signal task, which adjusts the stop signal delay automatically (by 50ms) to maintain the rate of successful inhibition on stop-signal trials at 50%.
Time frame: Baseline, Week 4, and Week 8
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Response Inhibition Training | Stop Signal Reaction Time | Baseline | 225.47 milliseconds | Standard Deviation 29.1 |
| Response Inhibition Training | Stop Signal Reaction Time | Week 4 | 215.68 milliseconds | Standard Deviation 21.74 |
| Response Inhibition Training | Stop Signal Reaction Time | Week 8 | 211.46 milliseconds | Standard Deviation 21.99 |
| Placebo Control Training | Stop Signal Reaction Time | Baseline | 225.83 milliseconds | Standard Deviation 18.96 |
| Placebo Control Training | Stop Signal Reaction Time | Week 4 | 212.92 milliseconds | Standard Deviation 18.82 |
| Placebo Control Training | Stop Signal Reaction Time | Week 8 | 208.69 milliseconds | Standard Deviation 42.77 |
Comparison: It was calculated that 30 participants randomized in a 1:1 fashion between the 2 arms would have .90 power to detect a large effect (f=.40), but is somewhat underpowered to detect a medium effect (f=.25) between the two groups. Sample size was determined using a repeated-measures ANOVA test (α = .05, a correlation of .5 among repeated measures, and a nonsphericity correction of .6), considering the design effect and potential patient attrition (=25%).p-value: =0.98Mixed Models Analysis
Secondary
Clinical Global Impression Severity and Improvement
The Clinical Global Impression Severity and Improvement (CGI) is a clinician-administered rating scale widely used to assess the overall severity of the target condition in treatment outcome research. The CGI is assessed on a 7-point scale, with the severity scale from 1 (Normal, not at all ill) through to 7 (Among the most severely ill patients). Thus, the higher CGI severity rating score indicate a greater level of overall illness.
Time frame: Baseline, Week 4, and Week 8
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Response Inhibition Training | Clinical Global Impression Severity and Improvement | Baseline | 3.67 score on a scale | Standard Deviation 0.69 |
| Response Inhibition Training | Clinical Global Impression Severity and Improvement | Week 4 | 3.63 score on a scale | Standard Deviation 0.89 |
| Response Inhibition Training | Clinical Global Impression Severity and Improvement | Week 8 | 3.20 score on a scale | Standard Deviation 1.01 |
| Placebo Control Training | Clinical Global Impression Severity and Improvement | Baseline | 4.00 score on a scale | Standard Deviation 0.54 |
| Placebo Control Training | Clinical Global Impression Severity and Improvement | Week 4 | 3.57 score on a scale | Standard Deviation 0.65 |
| Placebo Control Training | Clinical Global Impression Severity and Improvement | Week 8 | 3.69 score on a scale | Standard Deviation 0.75 |
Secondary
Commission Errors on the Go/No-go Task.
The number of commission errors on the go/no-go task is a commonly used measure of response inhibition. In this task, participants are asked to withhold their responses on no-go trials. If they fail to withhold their response in a no-go trial (i.e., pressing the response key to the no-go signal), this response counts toward the total number of commission errors. Therefore, a greater number of commission errors on this task reflects a greater level of inhibitory control deficit.
Time frame: Baseline, Week 4, and Week 8
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Response Inhibition Training | Commission Errors on the Go/No-go Task. | Baseline | 10.41 The number of commission errors | Standard Deviation 6.76 |
| Response Inhibition Training | Commission Errors on the Go/No-go Task. | Week 4 | 10.69 The number of commission errors | Standard Deviation 5.75 |
| Response Inhibition Training | Commission Errors on the Go/No-go Task. | Week 8 | 9.38 The number of commission errors | Standard Deviation 4.32 |
| Placebo Control Training | Commission Errors on the Go/No-go Task. | Baseline | 9.40 The number of commission errors | Standard Deviation 5.78 |
| Placebo Control Training | Commission Errors on the Go/No-go Task. | Week 4 | 15.64 The number of commission errors | Standard Deviation 8.9 |
| Placebo Control Training | Commission Errors on the Go/No-go Task. | Week 8 | 11.77 The number of commission errors | Standard Deviation 7.24 |