An observational study in Parasite and Infestation Physician-Patient Diagnostic Incongruency, sponsored by Vanderbilt University Medical Center. Recruiting at 1 site in United States. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-09-30.
Sponsored by Vanderbilt University Medical Center · Observational
Many people have evidence of bugs, parasites, and infestation, but are told by others that they cannot find a cause. This distressing and frustrating experience can last for years, as the person seeks answers. The current study aims to understand the experience of these individuals. In a 1-2 hour session over Zoom, the investigators will ask participants questions about their experience, have them complete self-report questionnaires, and ask them to complete a few games on the computer. The investigators' goal is to help characterize and understand individuals with this experience to aid in better treatment and inform recommendations for providers.
The current study aims to characterize the experiences of people who have evidence of bugs, parasites, and/or infestation but are told by physicians or other professionals (e.g. vets, pest control) that there is nothing wrong. The investigators seek to understand the emotional and cognitive aspects of this experience, through semi-structured interviews, self-report questionnaires, and cognitive tasks. The study will take a few hours and is conducted remotely, allowing for participation regardless of the participant's physical location. There is practically no aggregate information on this experience, with most current information relying on case reports and medical record review. The investigators hope to provide greater insights into this experience to guide support for individuals going through this difficult process.
62 studies on the registry are indexed under Parasitic Diseases; 13 are open to participants now.
This study's planned enrollment of 25 is below the median of 219 across 21 observational studies indexed under Parasitic Diseases.
Browse Parasitic Diseases studies →Vanderbilt University Medical Center is the lead sponsor of 824 studies on the registry; 164 are open to participants now.
Of its 122 completed or terminated interventional studies of FDA-regulated products, 91 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Adults with a persistent experience of infestation or parasite that physicians or other professionals report no evidence for.
Exclusion Criteria:
Other: No intervention - observational study
This study will not involve an intervention.
Psychological Wellbeing
Total score on the Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS); scores range from 14-70; higher scores reflect greater wellbeing
Time frame: Baseline
Social Network
Ludden Social Network Scale - total score; higher scores reflect larger and closer social network (score: 0-30)
Time frame: Baseline
Depression
Total score - Beck Depression Inventory -II; Scores range from 0-63 with higher scores reflecting worse depression
Time frame: Baseline
Anxiety
Perseverative Thinking Questionnaire (PTQ); scores range from 0-60, higher scores reflect more perseveration
Time frame: Baseline
Belief Updating
Expectations of prior volatility (mu3) calculated from reversal learning task; higher parameter scores reflect greater expectations of volatility
Time frame: Baseline
BADE
Evidence Integration Impairment (EII) will be calculated based on decisions on the Bias Against Disconfirmatory Evidence task. Higher scores reflect more difficulty integrating information
Time frame: Baseline
Interoceptive Awareness
Multidimensional Assessment of Interoceptive Awareness-2; scores range from 0-185; higher scores reflect better interpersonal awareness
Time frame: Baseline
Dissociation
Cernis Felt Sense of Anomaly Scale (CEFSA); scores range from 0-140, higher scores reflect more severe dissociative experiences
Time frame: Baseline
Childhood Trauma
Childhood Trauma Questionnaire (CTQ)- scores range from 5-100, higher scores reflect more severe childhood maltreatment
Time frame: Baseline
DACOBS
Davos Assessment of Cognitive Biases Scale; higher scores reflect more severe cognitive biases. Scores range from 42-294
Time frame: Baseline
Plan to share: Undecided
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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