Introduction

Persistent Postural-Perceptual Dizziness (PPPD) is a chronic functional vestibular disorder characterized by dizziness, unsteadiness, and non-vertiginous sensations exacerbated by upright posture, motion, and complex visual stimuli. In clinical practice, assessing patients with PPPD involves navigating complex differential diagnoses, particularly when evaluating for symptom exaggeration or non-organic factors. Reliable Clinical Decision Points (CDPs) are essential to distinguish genuine functional neurological disorder from intentional feigning.

CDP 1: Symptom Validity Testing

Formal symptom validity measures (SVTs) are critical CDPs. In PPPD evaluations, performance-based tests such as the Test of Memory Malingering (TOMM) or the Non-Verbal Medical Symptom Validity Test (NV-MSVT) can identify invalid effort. Patients with genuine PPPD typically pass these tests. However, those engaging in symptom exaggeration may show scores well below chance or inconsistent with observed function. A CDP emerges when a patient reports severe dizziness yet performs flawlessly on balance tasks when distracted (e.g., walking while talking on a phone), suggesting functional overlay or magnification.

CDP 2: Inconsistency in Clinical Findings

A hallmark CDP in PPPD is the discrepancy between subjective complaints and objective tests. Patients with malingering or significant symptom exaggeration often report extreme dizziness (e.g., "I can't stand for a second") yet demonstrate near-normal posturography or caloric testing. Another red flag is failure to improve with standard PPPD treatments (vestibular rehabilitation, SSRIs) despite documented adherence — this may indicate secondary gain. Clinicians should note if the patient's reported handicap exceeds what is plausible given imaging and physiologic testing.

CDP 3: Response to Visual and Postural Challenges

PPPD itself is defined by functional exacerbation with complex visual environments (e.g., grocery stores, scrolling screens). A CDP for exaggeration occurs when a patient claims instant, dramatic worsening from minimal visual stimuli (e.g., a single moving dot) but shows no objective changes in nystagmus or balance. Additionally, those with malingering may exhibit inconsistent reaction times or dramatic "give-way" weakness during physical exam, whereas true PPPD produces more consistent, measurable postural instability.

CDP 4: Psychosocial and Legal Context

Assessing context is vital. High-risk scenarios for malingering include pending litigation, disability applications, or a history of dishonesty. However, many PPPD patients have comorbid anxiety or depression — these are not synonymous with symptom exaggeration. A thoughtful CDP differentiates between amplified distress due to genuine functional symptoms versus deliberate fabrication. Collateral history and review of surveillance footage (when permissible) can be revealing.

CDP 5: Consistency across Multiple Examinations

Repeat evaluations are powerful CDPs. Patients with true PPPD usually show stable or slowly improving symptom patterns with treatment. Those with symptom exaggeration or malingering often provide inconsistent narratives, change symptom descriptions between sessions, or refuse objective testing. The "floating sign" — where the reported location of unsteadiness shifts — strongly suggests a functional overlay rather than pure PPPD.

Implications for Clinical Practice

Identifying symptom exaggeration in PPPD requires careful, non-judgmental assessment. Over-attributing symptoms to malingering can harm patients with actual functional disorders, while missing intentional feigning wastes resources and enables secondary gain. Using validated CDPs — including symptom validity tests, inconsistency analysis, and contextual review — improves diagnostic accuracy. Multidisciplinary collaboration between neurologists, otolaryngologists, and psychologists is recommended.

Conclusion

Distinguishing malingering from genuine functional PPPD remains challenging. A structured CDP approach — integrating symptom validity testing, meticulous observation for symptom exaggeration, and awareness of contextual factors — enables clinicians to provide appropriate, ethical care. By applying these decision points, healthcare providers can better serve patients with authentic PPPD while avoiding iatrogenic harm from false attribution of malingering.