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Modified Hoehn and Yahr Scale for Parkinson’s Disease

Calculators  Neurology
Modified Hoehn and Yahr Scale describes the progression of parkinson's disease based on the symptoms provided
Severity of symptoms
Unilateral involvement only 1
Unilateral and axial involvement 1.5
Bilateral involvement without impairment of balance 2
Mild bilateral disease with recovery on pull test 2.5
Mild to moderate bilateral disease; some postural instability; physically independent 3
Severe disability; still able to walk or stand unassisted 4
Wheelchair bound or bedridden unless aided 5


Measured Factor
Grades severity of parkinson's symptoms
Measured Factor Disease
  • Parkinsion's
Measured Factor Detail
Modified Hoehn and Yahr Scale estimates the severity of parkinson's disease by providing various stages of the disease. Higher the stage indicates higher disability chances.
Body System
Measured Factor Low Impact
  • Stage 1 indicates involvment of unillateral only.
Measured Factor High Impact
  • Stage 5 means that patient is unable to move on its own and is bedridden.

Result Interpretation

Ranges Ranges
Result High Conditions
  • Inability to move on its own
  • hallunications
  • delusions
Test Limitations
There are no clinimetric testing present for the adaptation of 0.5 increments in HY scale.
References: 2


Study Validation 1
The Movement Disorder Society Task Force reported the evaluation of the stages of Parkinson's disease (PD) with the Hoehn and Yahr scale (HY). Limited clinimetric testing of HY scale but modified HY scale added 0.5 increments which have been widely adopted. The Task Force proposes the use of HY scale for patient's demographic presentation in original form, HY scale primarily useful in inclusion and exclusion criteria in research, nonparametric methods should be used for analysis changes, reported medians, group description and ranges from the HY scale. The modified HY scale has been widely used with the adaptation of 0.5 increments but clinimetric testing should be done for this adaptations.
References: 2
Study Additional 1
A randomized trial was conducted of Yoga with functional improvements in Parkinson's disease (PD). Patients with PD experience problem in functional gait, balance, motor function, and postural stability. The objective of the study was to detect the improvement in balance control, changes in motor function, postural stability, and functional gait. There were 15 participants in yoga group experienced improvements in postural stability, freezing gait, functional gait, and motor function, also reduction in risk of fall. In control group, there was 12 participants experienced postural stability improvement but the risk of fall was not reduced. Yoga group reduced fall risk with 8-week yoga and also improve freezing and functional gait, postural stability of PD patients. In addition, PD stages were diagnosed with modified Hoehn and Yahr scale.
References: 3
Study Additional 2
A study was conducted between January 1998 to June 2003 in early Parkinson's disease (PD) for clinical characteristics in central California. 162 individuals diagnosed with clinical characteristics of PD. Male and Caucasian subjects were in majority between 60 to 79 years age. 92% subjects showed motor rigidity, 95.7% with bradykinesia, and 87% with gait problems and 43.3% were with tremor. 3/4th patients had stage 2 or higher with the Hoehn and Yahr scale. In addition, the study showed extensive phenotypic description of rural residents of US with initial stages of PD.
References: 4
Study Additional 3
A study was conducted to evaluate characteristics of self-concept and body image in patients with Parkinson's disease (PD) and depressive symptoms correlation. There were 48 individuals over 50 years age, 26 having PD and 22 were control participants. The scales were used for diagnosis: The My Body Image Test, The Beck Depression Inventory, The Mini Exam of  Mental State, The Modified Hoehn and Yahr Scale, The Factorial Self-concept Test, and The United Parkinson's Disease Rating Scale. Self-concept and body image demonstrated with p = 0.012 and p < 0.001, respectively reduced values, and significantly more with depressive symptoms (p = 0.002). In addition, alteration of self-concept and body image of individuals with PD and also lower personal confidence with depressive symptoms.
References: 5


  1. Hoehn MM, Yahr MD. Parkinsonism: onset, progression and mortality. Neurology. 1967;17(5):427-42.
  2. Goetz CG, Poewe W, Rascol O, Sampaio C, Stebbins GT, Counsell C, et al. Movement Disorder Society Task Force report on the Hoehn and Yahr staging scale: status and recommendations. Mov Disord. 2004;19(9):1020-8.
  3. Van puymbroeck M, Walter A, Hawkins BL, Sharp JL, Woschkolup K, Urrea-Mendoza E, et al. Functional Improvements in Parkinson's Disease Following a Randomized Trial of Yoga. Evid Based Complement Alternat Med. 2018;2018:8516351.
  4. Kang GA, Bronstein JM, Masterman DL, Redelings M, Crum JA, Ritz B. Clinical characteristics in early Parkinson's disease in a central California population-based study. Mov Disord. 2005;20(9):1133-42.
  5. Gamarra AH, Molski CS, Hilbig A, Valentini CK, Striebel VL, Rieder CR. Evaluation of body image and self-concept and their correlation with depressive symptoms in Parkinson's disease. Arq Neuropsiquiatr. 2009;67(3A):585-90.