Figure 1
Vertical Model of Theoretical Frameworks Underpinning Symptom Expression in FND.
This model was developed by the author to illustrate the conceptual relationship between stress vulnerability, dynamic symptom fluctuation, and functional neurological symptoms.
Adapted and conceptualized by the author based on the Stress-Vulnerability Model [22] and Dynamical Systems Theory [5].
Figure 2
Prisma Flow Diagram.
PRISMA-ScR flow diagram illustrating the screening and selection process.
Adapted from Adapted from Tricco et al. [30].
Table 1
Measures related to Stress-Related Motor Symptoms in Functional Neurological Disorder (FND).
| INSTRUMENT NAME | AUTHOR & YEAR | OVERVIEW | POPULATION | RELIABILITY | VALIDITY TYPES | RESPONSIVENESS | STRENGTHS | LIMITATIONS |
|---|---|---|---|---|---|---|---|---|
| FuNDRS | Brar [3] | Assesses symptom severity and frequency specifically in FND patients. | FND patients | α = 0.78 | Construct validity | Moderate | Easy administration | Not explicitly stress-focused |
| S-FMDRS | Nielsen et al. [18] | Simplified clinician-administered scale to evaluate motor symptoms in functional movement disorders. | Functional Movement Disorder | ICC = 0.85 | Criterion, Construct | Good | Clinician-friendly | Limited stress-related questions |
| PSS-10 | Cohen et al. [4] | Widely used scale measuring perceived stress in various populations. | General populations, patients with stress | α = 0.89 | Construct, Criterion | High | Widely validated, stress-specific | Not specific to motor symptoms |
| DASS-21 | Lovibond & Lovibond [17] | Measures depression, anxiety, and stress in general populations. | Psychological distress | α = 0.94 | Construct validity | High | Well-validated, comprehensive | General psychological distress, lacks motor focus |
| PDQ-39 | Peto et al. [20] | Measures quality of life and symptom burden specifically in Parkinson’s disease. | Parkinson’s patients | α = 0.93 | Construct, Criterion | High | Validated motor symptom assessment | Disease-specific (Parkinson’s), not stress-focused |