The diagnosis of a neurodegenerative disorder profoundly alters the trajectory of an individual’s life, creating complex physical, psychological, and social challenges. Among the foremost institutions dedicated to alleviating this burden in the United States is the American Parkinson Disease Association, Inc. (APDA). Founded in the mid-twentieth century, the organization represents a critical bridge connecting clinical neuroscience, laboratory research, patient advocacy, and grassroots community support systems designed to optimize the quality of life for millions affected by movement disorders.
American Parkinson Disease Association, Inc. (APDA)
1. Concise Definition
The American Parkinson Disease Association, Inc. (APDA) is a major United States non-profit grassroots health organization dedicated to supporting individuals diagnosed with Parkinson’s disease (PD), their care partners, and medical professionals. Through a nationwide network of chapters, Information & Referral (I&R) Centers, and multidisciplinary programs, the APDA delivers patient education, emotional support, and social services while actively funding cutting-edge scientific research directed toward discovering the underlying etiology, improving therapeutic interventions, and ultimately finding a cure for the illness.
As an institutional entity within the broader public health and neurological advocacy sector, the APDA operates simultaneously at micro- and macro-levels. At the micro-level, it provides personalized counseling, localized wellness initiatives, respite care financial grants, and symptom management resources to affected families. At the macro-level, it serves as a philanthropic research engine and a public policy advocate, financing basic science investigations, translational biomedical studies, and early-career physician-scientists striving to decipher the mechanisms of neurodegeneration.
2. Etymology & Linguistic Origin
The nomenclature of the American Parkinson Disease Association derives from three distinct linguistic and historical components: geographic designation, medical eponymy, and corporate taxonomy. The geographic qualifier “American” originates from the Latinized name Americus (honoring Italian navigator Amerigo Vespucci), functioning here to delineate the primary territorial jurisdiction and organizational origin within the United States.
The medical term “Parkinson” constitutes a classic medical eponym honoring the English apothecary surgeon and paleontologist James Parkinson. In 1817, Parkinson published his seminal clinical monograph, An Essay on the Shaking Palsy, which first systematically documented the constellation of resting tremor, muscular rigidity, postural instability, and festinating gait under the diagnostic label paralysis agitans. The subsequent adoption of “Parkinson’s disease” (French: maladie de Parkinson) was popularized in the late nineteenth century by the renowned French neurologist Jean-Martin Charcot, who sought to honor Parkinson while clarifying that the condition involved significant rigidity and bradykinesia rather than true loss of muscular strength.
The constituent terms “Disease” (derived from the Old French desaise, meaning lack of ease or discomfort) and “Association” (from the Medieval Latin associationem, denoting a union, partnership, or fellowship) reflect the organizational mission: a formalized coalition of people united to address and overcome a debilitating medical condition. The designation “Inc.” (Incorporated) signifies its legal incorporation under American corporate law as a recognized charitable entity.
3. Pronunciation & Grammatical Form
The institutional name is pronounced phonetically in American English as /əˈmɛrɪkən ˈpɑːrkɪnsən dɪˈziːz əˌsoʊsiˈeɪʃən, ɪŋk/, commonly abbreviated as the initialism /ˌeɪ piː diː ˈeɪ/. Grammatically, “American Parkinson Disease Association” operates as a proper noun phrase. It routinely accepts the definite article (“the APDA”) when functioning as a nominal subject or object in declarative sentences.
Variations in common usage include the occasional omission of the corporate suffix “Inc.” in journalistic and casual healthcare communication, as well as the stylistic debate regarding the possessive versus non-possessive form of the eponym. While historical neurology literature frequently employed the possessive “Parkinson’s Disease Association,” the official legal charter established the title non-possessively as “Parkinson Disease Association,” consistent with prevailing terminology standards established by the World Health Organization and standard medical lexicons that discourage possessive eponyms.
4. Detailed Conceptual Explanation
To comprehend the structural significance of the APDA, one must examine the biomedical and social landscape of neurodegenerative illness. Parkinson’s disease represents the second most prevalent progressive neurodegenerative disorder worldwide, trailing only Alzheimer’s disease. Pathologically characterized by the profound loss of dopaminergic neurons within the substantia nigra pars compacta and the intracellular aggregation of misfolded alpha-synuclein into Lewy bodies, the disease manifests through classical motor symptoms—such as tremor at rest, bradykinesia, rigidity, and gait impairment—alongside debilitating non-motor symptoms, including autonomic dysfunction, cognitive decline, sleep architecture disturbances, depression, and anxiety.
Within this complex biomedical milieu, the APDA fulfills a triadic operational paradigm composed of education, direct support, and scientific research funding. Rather than functioning purely as an academic research institute or exclusively as a mutual-aid society, the APDA synthesizes these domains to address what public health researchers term the “continuum of care gap.” Medical clinics frequently provide diagnostic confirmation and pharmacotherapeutic prescriptions (such as levodopa formulations or dopamine agonists) but remain constrained by clinical time limits, leaving patients with insufficient guidance regarding physical rehabilitation, nutritional adjustments, and psychosocial coping mechanisms.
The APDA steps into this void through its structured Information & Referral (I&R) network, strategically embedded within academic medical centers across the United States. These centers serve as regional clearinghouses staffed by clinical nurse specialists, licensed clinical social workers, and allied health professionals. They translate complex neurological literature into accessible health education, guide families through complicated health insurance systems, facilitate support groups, and coordinate symptom-specific non-pharmacological interventions such as speech therapy programs, tailored aerobic exercise classes, and therapeutic art and movement workshops.
Furthermore, the APDA conceptualizes research funding not as an isolated philanthropic exercise, but as a strategic venture capital framework for scientific discovery. By prioritizing seed funding, postdoctoral fellowships, and research grants for early-stage investigators, the association deliberately nurtures novel, high-risk, high-reward hypotheses that might fail to capture immediate funding from traditional federal institutions like the National Institutes of Health (NIH). Through this funding philosophy, the organization accelerates the discovery pipeline, supporting basic biological inquiry that often forms the prerequisite data required for subsequent multi-million-dollar federal clinical trials.
5. Historical Development
The genesis of the American Parkinson Disease Association dates back to 1961 in New York City. During this post-war era, clinical neurology possessed minimal pharmacological weaponry against Parkinson’s disease; the revolutionary therapeutic benefits of oral levodopa had not yet been clinically demonstrated, and neurosurgical stereotactic thalamotomy was still in an experimental, high-risk stage. Patients diagnosed with the disease faced rapid, progressive debilitation and were largely relegated to long-term chronic care institutions or isolated within domestic environments without public support networks.
Recognizing this profound unmet clinical and social need, a dedicated cohort of civic leaders, philanthropists, and visionary clinicians—most notably including early leaders at the Mount Sinai Hospital in New York—established the APDA. Their fundamental mission was to dismantle the pervasive stigma surrounding movement disorders, provide tangible relief to struggling families, and generate financial capital dedicated to biomedical inquiry into the pathology of movement disorders.
Over the ensuing decades, the APDA underwent rapid geographic and programmatic expansion, marked by several transformative milestones:
- 1970s: The Creation of the Information & Referral Center Model: The APDA established its first specialized I&R Centers within major tertiary hospitals. This structural innovation recognized that centralized healthcare institutions needed localized community outreach arms to facilitate patient adherence, education, and long-term care management.
- 1980s: Rapid National Expansion: The organization founded regional chapters across the Midwest, South, and Western United States, transitioning from a regionally focused Northeast initiative into a nationwide non-profit network capable of mobilizing thousands of volunteers and community advocates.
- Late 1990s and 2000s: The Genetic and Molecular Era: In conjunction with the groundbreaking identification of mutations in the SNCA (alpha-synuclein) gene and other genetic loci associated with familial Parkinsonism, the APDA shifted significant grant allocations toward molecular genetics, neuropathology, and cellular biology, awarding millions of dollars to elite academic research laboratories.
- 2010s to Present: Digital Transformation and Health Equity: The organization expanded its digital presence, launching nationwide bilingual education programs, accessible telehealth initiatives, and targeted outreach programs designed to reach historically underserved populations, including rural communities and minority demographic groups disproportionately affected by delayed diagnoses.
6. Theoretical Foundations
The organizational architecture and strategic methodologies of the APDA are rooted in multiple complementary theoretical paradigms drawn from medical sociology, behavioral psychology, and healthcare management. Foremost among these is the Biopsychosocial Model of health, originally formulated by psychiatrist George Engel. The APDA rejects the reductionist view that Parkinson’s disease is merely a localized neurological failure of dopaminergic pathways. Instead, its programs acknowledge that the disease is a systemic condition influencing emotional wellbeing, familial relationships, financial stability, and community engagement. By financing respite care grants, facilitating psychological counseling, and organizing caregiver retreats alongside medical symposia, the APDA operationalizes the biopsychosocial framework in contemporary clinical advocacy.
A secondary theoretical foundation is derived from Albert Bandura’s Self-Efficacy Theory. In chronic and incurable neurodegenerative illnesses, patients frequently experience profound psychological distress, learned helplessness, and a loss of personal agency as motor automaticity declines. The APDA counters this progressive disempowerment through targeted self-management training, education on disease trajectory, and structured group exercise initiatives. By fostering mastery experiences—such as learning adapted movement patterns or achieving communicative clarity through specialized speech therapy—the organization elevates patient self-efficacy, which empirical literature directly associates with improved therapeutic adherence, reduced subjective symptom burden, and mitigated depressive symptoms.
Finally, the APDA exemplifies the sociology of Health Social Movements (HSMs) and embodied health movements. In these paradigms, patients, caregivers, and allied scientists organize collectively to contest medical knowledge boundaries, influence federal resource allocation, and democratize clinical research agendas. Through continuous advocacy efforts, the APDA bridges the conventional power divide between clinical researchers and patient populations, transforming patients from passive clinical subjects into active collaborators who guide the direction of institutional investigation.
7. Key Components, Types & Dimensions
The operational framework of the American Parkinson Disease Association can be systematically broken down into distinct organizational components and programmatic dimensions:
- Nationwide Chapter Infrastructure: Regional community chapters operating across multiple states provide grassroots mobilization, local fundraising events (such as the signature “Optimism Walk” series), community educational symposiums, and peer-led support network meetings.
- Information & Referral (I&R) Centers: Hospital-affiliated centers located within renowned university medical centers that function as localized resource hubs staffed by healthcare coordinators, movement disorder specialists, and clinical social workers who offer direct clinical guidance and system navigation.
- Scientific Advisory Board (SAB): A distinguished body of world-renowned neuroscientists, neurologists, and movement disorder specialists who conduct rigorous peer reviews of all research grant applications, ensuring that philanthropic investments meet the highest standards of scientific validity and innovation.
- Research Funding Portfolios: Structured grant categories encompassing Postdoctoral Research Fellowships, Research Grants for independent investigators, and Diversity Research Grants designed to recruit and fund investigators from historically underrepresented scientific backgrounds.
- Care Partner Support Initiatives: Targeted programmatic resources—such as educational seminars, specialized literature, support groups, and emergency financial assistance—aimed specifically at reducing caregiver burden, mitigating burnout, and addressing the psychological strain experienced by spouses, adult children, and primary care partners.
- Health and Wellness Programs: Standardized and evidence-based non-pharmacological initiatives, including adapted yoga, boxing, dance, and balance-training curricula specifically modified for individuals exhibiting postural instability and motor freezing.
- Bilingual and Multicultural Outreach: Dedicated resource streams, educational handbooks, webinars, and localized support services provided natively in Spanish and other languages to overcome cultural and linguistic barriers to neurological care.
8. Examples & Illustrative Cases
The practical utility of the APDA is best illustrated through realistic scenarios demonstrating how its institutional resources intervene at various stages of the disease trajectory.
Case Illustration 1: The Newly Diagnosed Patient
A 54-year-old structural engineer receives a definitive diagnosis of young-onset Parkinson’s disease (YOPD) after noticing a persistent resting tremor in his non-dominant hand and subtle handwriting changes (micrographia). Overwhelmed by anxiety regarding career longevity, financial stability, and disease progression, the patient contacts an APDA Information & Referral Center. The center pairs him with an educational coordinator who provides clear literature explaining dopamine replacement therapy, directs him to an employment-rights legal workshop, and connects him to a specialized YOPD peer support group. Additionally, the coordinator enrolls him in a community-based high-intensity cycling group shown to stimulate neuroplasticity. Within months, the patient transitions from existential crisis to active self-management, maintaining professional productivity while implementing evidence-based lifestyle modifications.
Case Illustration 2: The Advanced Disease Caregiver Crisis
A 76-year-old woman serves as the sole care partner for her husband, who has lived with Parkinson’s disease for sixteen years. The patient has entered the advanced stages of the disease, experiencing recurrent visual hallucinations, severe motor fluctuations (abrupt “off” periods), and nocturnal disruptions. The caregiver is physically and emotionally exhausted, exhibiting symptoms of severe clinical depression and musculoskeletal strain from assisting with transfers. Through an APDA emergency support initiative, the caregiver receives a financial grant for short-term in-home respite care, allowing her to rest and attend to her own medical needs. Simultaneously, an APDA clinical social worker helps the family navigate local hospice and palliative care resources, transition to a movement-disorder-informed home safety setup, and participate in a virtual caregiver grief and coping group.
9. Measurement & Assessment
Although the APDA is primarily an advocacy, educational, and funding organization rather than a diagnostic tool itself, its clinical programs, scientific studies, and sponsored initiatives routinely utilize standardized clinical assessment metrics to evaluate disease progression and programmatic efficacy. Understanding these assessment mechanisms is central to understanding how the APDA evaluates patient outcomes:
In scientific research funded by the APDA and clinical programs within its I&R centers, the primary gold standard measurement system is the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). This comprehensive, multi-part instrument measures non-motor experiences of daily living (Part I), motor experiences of daily living (Part II), an objective clinician-scored motor examination (Part III), and motor complications including dyskinesias and motor fluctuations (Part IV). Clinicians and APDA-supported researchers utilize the UPDRS to track disease velocity and assess the therapeutic efficacy of pharmacological agents or exercise protocols.
Additionally, the APDA assesses disease staging utilizing the Hoehn and Yahr Scale, which categorizes clinical progression from Stage 1 (unilateral involvement with minimal functional impairment) through Stage 5 (confinement to bed or wheelchair unless assisted). To measure non-motor dimensions and patient-centered quality of life, APDA programs systematically apply validated psychological and health-related quality of life scales, such as the Parkinson’s Disease Questionnaire (PDQ-39), the Zarit Burden Interview (ZBI) for evaluating care partner stress, and the Beck Depression Inventory (BDI) or Geriatric Depression Scale (GDS) for tracking comorbid neuropsychiatric symptoms.
10. Applications & Practical Significance
The applications and practical significance of the APDA extend throughout the healthcare and social services infrastructure, yielding benefits across four interconnected arenas:
Clinical Medicine and Multidisciplinary Care: The APDA advocates for and finances the integration of comprehensive interdisciplinary teams in routine clinical practice. By coordinating neurologists, physiatrists, physical therapists, occupational therapists, speech-language pathologists, and mental health professionals, the organization helps establish evidence-based standards of holistic care that reduce preventable hospitalizations from falls, aspiration pneumonia, and adverse drug interactions.
Public Health and Policy Advocacy: The APDA engages with regulatory and legislative bodies to advance policies advantageous to the neurodegenerative disease community. This includes advocating for expanded federal funding allocations through the National Institutes of Health and the Centers for Disease Control and Prevention, lobbying for enhanced protections under the Americans with Disabilities Act, and supporting legislative initiatives to ban environmental toxins (such as the pesticide paraquat) strongly associated with elevated epidemiological risks of developing Parkinson’s disease.
Biomedical Innovation and Pipeline Development: By providing early career seed grants, the APDA functions as a primary pipeline for translational science. Prominent scientific discoveries—ranging from investigations into mitochondrial dysfunction, neuroinflammation, neuroprotective cellular pathways, and novel deep brain stimulation (DBS) paradigms—have traced their foundational, proof-of-concept financing directly to APDA research grant programs.
Community Integration and Public Education: Through continuous awareness campaigns, educational manuals, podcasts, and community symposia, the APDA actively de-stigmatizes motor symptoms such as tremors, facial masking (hypomimia), and speech changes (hypophonia). This education fosters public empathy, encourages timely clinical diagnoses, and empowers patients to remain integrated within their communities rather than withdrawing into social isolation.
11. Research & Empirical Evidence
The empirical footprint of the American Parkinson Disease Association is deeply embedded in decades of peer-reviewed neurological literature. Since its inception, the APDA has raised and invested tens of millions of dollars into clinical and basic scientific research, funding thousands of investigative projects across the globe.
A critical contribution of APDA-funded researchers includes unraveling the molecular cascades of cell death in the substantia nigra. For instance, investigations supported by the APDA have explored how the physiological protein alpha-synuclein undergoes pathological conformational changes, aggregating into toxic oligomers and fibrils that spread through neuroanatomical networks in a prion-like manner. Early funding from the APDA has supported investigators evaluating the role of ubiquitin-proteasome system failure and autophagy-lysosomal pathway defects in clearing these neurotoxic aggregates.
Furthermore, the APDA has contributed significantly to the empirical literature surrounding exercise as a non-pharmacological, disease-modifying intervention. Clinical trials supported directly or facilitated logistically through APDA networks have confirmed that targeted physical exercise—such as aerobic cycling, progressive resistance training, and sensory-cued treadmill walking—not only enhances functional gait mechanics and decreases fall incidence, but also stimulates the expression of brain-derived neurotrophic factor (BDNF), enhances synaptic plasticity, and may confer genuine neuroprotective benefits to vulnerable neural circuits.
Prominent clinical scientists who have received support from the APDA throughout their careers have gone on to lead major scientific divisions, direct university movement disorder centers, and author seminal studies in journals such as The New England Journal of Medicine, The Lancet Neurology, and Movement Disorders, highlighting the catalytic impact of the organization’s funding model.
12. Cultural & Cross-Cultural Considerations
The experience, diagnosis, and management of Parkinson’s disease are significantly modulated by cultural frameworks, socio-economic status, and linguistic contexts. The APDA has increasingly directed institutional focus toward understanding and overcoming these disparities.
Cross-cultural epidemiological and clinical studies reveal persistent disparities in timely diagnosis and treatment access. In many underrepresented communities, the early motor and cognitive manifestations of Parkinson’s disease are frequently misattributed to natural, inevitable biological aging (senescence), leading to severe delays in neurological consultation and initiation of effective pharmacotherapies. In certain cultural environments, the outward physical presentation of tremors or unsteady gait carries significant social stigma or misconceptions regarding substance abuse, prompting social withdrawal and concealment of symptoms.
The APDA addresses these barriers by designing targeted community initiatives. Recognizing that healthcare access is heavily stratified by insurance status, language literacy, and geographical location, the organization provides extensive Spanish-language literature, translates symposia, and partners with community clinics in underserved rural and urban areas. By working with culturally competent healthcare navigators, the APDA seeks to demystify neurological disorders, provide educational resources framed within appropriate cultural concepts, and ensure that cutting-edge therapies and clinical trials are accessible to all demographics regardless of socioeconomic status.
13. Criticisms, Debates & Limitations
Despite its significant contributions to the healthcare ecosystem, the APDA—like other major disease-specific non-profit organizations—operates within an environment characterized by systemic tensions, structural limitations, and ongoing debates regarding operational priorities.
Allocation of Financial Resources: Research vs. Patient Services: A perpetual philosophical and operational debate within the leadership and donor base of the APDA concerns the optimal distribution of capital between basic scientific research and immediate, direct patient care programs. One philosophical camp maintains that the paramount objective of a disease-specific non-profit must be the complete eradication of the disease through aggressive funding of high-risk molecular biology and translational therapeutics. Conversely, another camp argues that until a definitive biological cure is achieved, the primary ethical imperative must be the provision of immediate, localized relief: financing respite care, subsidizing physical therapy, and sustaining localized support infrastructure for families currently struggling with the debilitating daily realities of the illness.
Philanthropic Fragmentation and Redundancy: Health policy analysts occasionally critique the fragmented landscape of neurodegenerative disease advocacy. Multiple distinct organizations—such as the APDA, the Michael J. Fox Foundation for Parkinson’s Research, the Parkinson’s Foundation, and the Davis Phinney Foundation—compete for philanthropic dollars, corporate sponsorships, and public attention within the same medical demographic. Critics suggest that this competitive ecosystem can lead to redundant administrative overhead, duplicative research grants, and fragmented lobbying efforts. However, proponents counter that organizational pluralism fosters diverse funding strategies, with the APDA maintaining a unique, irreplaceable grassroots niche focused on local Information & Referral networks that larger, research-exclusive foundations do not support.
Geographic Centralization and Resource Equity: Despite a commitment to national outreach, practical resource availability remains naturally clustered around major metropolitan areas and elite academic medical centers where APDA chapters and I&R centers are physically located. Patients residing in rural medical deserts, or those lacking access to broadband internet for telehealth services, often experience reduced access to APDA-sponsored programs compared to individuals residing in close proximity to major neurological referral hubs.
14. Related Terms & Distinctions
To ensure academic clarity, it is essential to distinguish the APDA from related terms, clinical concepts, and peer organizations operating within the same biomedical domain:
- Parkinson’s Disease (PD) vs. Parkinsonism: Parkinson’s disease is an idiopathic, progressive neurodegenerative clinical-pathological entity defined by dopamine loss and Lewy pathology. “Parkinsonism” is a broad umbrella term describing any clinical syndrome featuring tremors, bradykinesia, and rigidity, which may stem from atypical neurodegenerative disorders (e.g., Progressive Supranuclear Palsy, Multiple System Atrophy), medications (drug-induced parkinsonism), or cerebrovascular disease (vascular parkinsonism). The APDA serves individuals with idiopathic PD as well as those navigating related atypical parkinsonian conditions.
- The APDA vs. The Parkinson’s Foundation: While both are national non-profit entities dedicated to the illness, the Parkinson’s Foundation was formed through the merger of the National Parkinson Foundation (NPF) and the Parkinson’s Disease Foundation (PDF), operating a prominent designated “Centers of Excellence” network. The APDA maintains its own distinct institutional history, charter, and dedicated network of Information & Referral Centers, often collaborating collegially while operating independent philanthropic and programmatic streams.
- The APDA vs. The Michael J. Fox Foundation (MJFF): The MJFF is the largest non-profit funder of Parkinson’s research globally, directing its resources almost exclusively toward funding translational biomedical research, biomarker identification, and drug development. In contrast, the APDA balances biomedical research funding with a primary commitment to localized community support, direct social services, and grassroots care partner initiatives.
- Neurologist vs. Movement Disorder Specialist: A general neurologist diagnoses and manages conditions across the entire central and peripheral nervous system. A movement disorder specialist is a neurologist who has completed an additional fellowship specifically focusing on Parkinson’s disease and related conditions. The APDA frequently collaborates with and funds movement disorder specialists to lead its I&R centers and review boards.
15. Key Takeaways
The American Parkinson Disease Association, Inc. (APDA) serves as a cornerstone of the modern movement disorder care infrastructure in the United States. Established in 1961, the organization addresses the multidimensional burden of Parkinson’s disease through a comprehensive, three-pronged strategy prioritizing community-based patient education, care partner support networks, and innovative early-stage scientific research funding. By operationalizing the biopsychosocial model of health, the APDA bridges the gap between acute clinical treatment and the long-term, everyday realities of living with a progressive, incurable neurodegenerative condition, ensuring that individuals and families maintain dignity, empowerment, and hope throughout their journey.
Through its extensive national network of chapters, hospital-based Information & Referral Centers, and an esteemed Scientific Advisory Board, the APDA acts as an accelerator for therapeutic innovation while serving as a compassionate safety net for vulnerable populations. By actively combating socio-economic and cultural disparities in neurological care, championing non-pharmacological interventions like targeted exercise, and guiding biomedical scientists toward groundbreaking discoveries, the organization continues to advance the clinical horizon toward improved symptomatic therapies, neuroprotective treatments, and an ultimate biological cure.
References
- American Parkinson Disease Association. (2023). About APDA: Our history and mission. https://www.apdaparkinson.org
- Charcot, J.-M. (1877). Lectures on the diseases of the nervous system. New Sydenham Society.
- Engel, G. L. (1977). The need for a new medical model: A challenge for biomedicine. Science, 196(4286), 129–136. https://doi.org/10.1126/science.847460
- Goetz, C. G., Tilley, B. C., Shaftman, S. R., Stebbins, G. T., Fahn, S., Martinez-Martin, P., Poewe, W., Sampaio, C., Stern, M. B., Dodel, R., Dubois, B., Holloway, R., Jankovic, J., Kulisevsky, J., Lang, A. E., Lees, A., Leurgans, S., LeWitt, P. A., Nyenhuis, D., … LaPelle, N. (2008). Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS): Scale presentation and clinimetric testing results. Movement Disorders, 23(15), 2129–2170. https://doi.org/10.1002/mds.22340
- Parkinson, J. (1817). An essay on the shaking palsy. Sherwood, Neely, and Jones.
- Poewe, W., Seppi, K., Tanner, C. M., Halliday, G. M., Brundin, P., Volkmann, J., Schrag, A.-E., & Lang, A. E. (2017). Parkinson disease. Nature Reviews Disease Primers, 3, Article 17013. https://doi.org/10.1038/nrdp.2017.13