Study Design


With comprehensive insight from researchers with varied expertise, PPMI has been designed to produce the most comprehensive Parkinson’s disease data set available to the scientific community. PPMI has built a dynamic, extensive infrastructure that is widely recognized as a valuable resource for research and study design. Its utility is also based in its longitudinal follow-up of multiple cohorts of interest to the scientific community.

PPMI’s protocols for standardized collection, transfer and storage of clinical and imaging data and biological samples are foundational to its value. These methods are now a model for other studies, as well, allowing for more cross-study comparison.

To achieve standardization across many clinical sites and cores, the study has created an extensive study protocol, data collection standards and processes, and data and biospecimen use agreements and policies. This section of the site provides insight into the study design and access to primary study documents, study statistics and general questions about the rationale for the protocol.

PPMI enrollment was paused in 2018 and re-started in 2020 with an updated study design and enrollment targets. While a substantial portion of the study design has remained the same, the schedule of activities has changed slightly in response to scientific and technological advances. Please refer to the current and prior protocols and schedules of activities below for full details. Additionally, the table below provides an overview of the enrollment details by cohort.

PPMI Research Documents and SOPs.

 

PD Cohort
N=423
Continuing: N=58
Target total: N=1,123

Enrollment: Jun 2010-Apr 2013

Follow-up: ongoing

Enrollment: Jul 2020-ongoing

Follow-up: ongoing

Genetic PD Cohort
N=294
Continuing: N=49
Target total: N=604

Enrollment: Feb 2014-Nov 2017

Follow-up: ongoing

Enrollment: Jul 2020-ongoing

Follow-up: ongoing

Prodromal Cohort
N=512
Continuing: N=120
Target total: N=2732

Enrollment: Jul 2013-Mar 2015

Follow-up: ongoing

Enrollment: Jul 2020-ongoing

Follow-up: ongoing

Healthy Control Cohort
N=196
Continuing: N=24
Target total: N=316

Enrollment: Jun 2010-Apr 2013

Follow-up: ongoing

Enrollment: Jul 2020-ongoing

Follow-up: ongoing

SWEDD

Cohort

N=64
No new enrollment

Enrollment: Aug 2011-Apr 2013

Follow-up: 2yrs

Last Update: March 2, 2021



Stats Forum

A stats forum exists for investigators who are interested in accessing or who have accessed the PPMI database to get additional information about the dataset or to ask questions about it. This area of the site is moderated by the PPMI Statistics Core, led by Christopher Coffey, PhD.