OBJECTIVES: To assess Parkinson’s Disease (PD) progression using the Hoehn and Yahr (H&Y) scale over the complete disease course based on systematic literature review with meta-analysis.  No systematic review of PD studies using H&Y has been undertaken.  Such findings could support models to evaluate economic effects of disease modifying therapies. METHODS: A systematic literature review (PubMed) was conducted to identify research since 1990 that reported longitudinal H&Y outcomes to obtain progression time data. Reference lists from retrieved articles were also reviewed and supplemented with recommendations from an expert neurologist. Statistical moments (e.g., survival at time t, median time to progress) were extracted and expected time to progress to the subsequent stage was calculated assuming a constant hazard rate of progression with a binomial distribution for progression rates.  Average time to progress through all stages of disease was calculated.  Random effects meta-analysis was performed to assess heterogeneity between studies between each stage in progression. RESULTS: Of 554 identified relevant titles, 56 articles were reviewed.  Ten studies, including one open label extension (OLE) trial and nine cohort studies, reported longitudinal H&Y outcomes for 3,687 patients observed over an average of 13.5 years.  Weighted by study sample sizes, expected time to progress from H&Y 1 to H&Y 5 was 162.1 months.  The OLE trial had longest expected total progression time (431.8 months, N=110); other studies ranged from 102.0 to 171.7 months. Time from H&Y stage 1–stage 2, 2–3, 3–4, and 4–5 were 32.3, 60.5, 42.9 and 26.4 months, respectively.  Meta-analysis indicated significant heterogeneity in progression time between studies (I2>95%).  Omitting single studies did not affect pooled estimates. CONCLUSIONS: Economic assessment of impacts of PD disease modification can consider expected progression rates over the full course of the disease. Progression rates are most rapid from H&Y stage 4 to 5.