The UCI ADRC Data Management and Statistics Core (DMSC) Researcher’s Guide is intended for investigators within and outside of the UCI ADRC who wish to undertake research projects using data from the UCI ADRC Clinical and Neuropathology databases. The Guide includes basic summary tables of the existing ADRC databases and is intended to provide researchers with aggregate level data to understand the feasibility of potential research studies. In addition, the Guide provides descriptions of ADRC standard analysis files (SAFs), the primary means by which ADRC data are available for use. In collaboration with DMSC statisticians and database personnel, it is intended that the Researcher’s Guide contains the necessary information needed to select and use the appropriate SAFs for an intended project.
Navigate this guide:
Jump to ADRC Standard Analysis Files
Jump to Data Collection
Jump to Neuropsychological Testing
Jump to Description of the longitudinal Cohort
Jump to Data Completeness
Jump to Clinical characteristics of the Longitudinal Cohort
Jump to Description of the neuropathology database
Jump to Contents of Standard Analysis Files
All ADRC data are available in SAS datasets that were created in the Windows environment and can be used only on the Windows operating system. Using the datasets on another computer platform requires moving and converting the data to SAS datasets for that platform. Using another data analysis system requires a conversion to a format compatible with that system. If a researcher wishes to receive ADRC in a different format (eg. .txt, .csv, etc) this can be done, however variable formats will not be automatically attached to the dataset.
Instructions for opening and using SAS formats are available here.
ADRC data collection forms consist of an initial packet form collecting baseline data, clinical assessment forms used for longitudinal memory assessment at annual followup visits, and neuropathology report forms completed at the time of autopsy. PDF copies of each of all ADRC data collection forms can be obtained from the links below.
- NACC Uniform Data Set (UDS) Initial Packet Forms
- UCI Memory Assessment Clinic Forms
- UCI ADRC Neuropath Final Report Form
Patients in the ADRC clinical cohort are assessed annually within the ADRC clinic to monitor cognitive ability. While most cognitive tests have been performed consistently over time, some tests have been implemented, discontinued, or modified over the years to incorporate changes to the NACC data collection process. The figures here provide a graphical depiction of the neuropsychological tests conducted annually at the ADRC clinic. For more information on changes to particular tests please contact the DMSC using the information on the Contact Us page.
The ADRC longitudinal cohort has followed patients since 1988. The Uniform Data Set (UDS) was implemented in 2005, standardizing much of the clinic’s data collection across all ADRC’s in the nation. Since that time a total of N=465 patients have been assessed at the clinic and 302 of these patients are currently being actively followed. After an initial baseline visit, patients are assessed annually for memory impairment. Tables and figures describing the frequency of patient visits for the cohort are available here. Note that patients with greater than 7 visits were seen at the clinic prior to the implementation of the UDS in 2005 and hence some of the data collection procedures changed at that time.
A primary goal of the ADRC is to identify and quantify those factors that are associated with the progression of dementia. The ADRC longitudinal cohort has data on multiple patients that have transitioned from normal cognition to mild cognitive impairment and alzheimer’s disease. The number of longitudinal patients who have progressive disease and the rate of disease progression is provided here.
The tables provided below yield basic descriptive statistics on the clinical cohort as reported by the National Alzheimer’s Coordinating Center (NACC) on October 1, 2013. These tables including summary statistics on followup of patients and data completeness. The total number of reported patients in these tables tends to be low relative to the current size of the cohort due to reporting lags, but they are useful for assessing the completeness of our data.
- Patient enrollment by followup status
- Frequency of patients by most recent diagnosis
- Monthly net gain/loss of patients in the clinical cohort
- Number of followup visits by visit type
- Proportion of missing neuropsychological tests over past 6 months
Below are summary statistics to describe the demographic and clinical composition of the longitudinal cohort. The tables summarize key questions included in the UDS that pertain to patient status including basic demographics, family and health history, neuropsychological evaluation, and neurologist diagnosis. These data are presented to provide researchers with an overview of the longitudinal cohort in order to assess the feasibility of new research projects utilizing the longitudinal cohort. Further summary measures or full datasets can be requested by visiting the data request page.
- NACC UDS Subject Demographics (A1)
- NACC UDS Subject Family History (A3)
- NACC UDS Subject Health History (A5)
- NACC UDS Evaluation Form – Physical (B1)
- NACC UDS Evaluation Form – Behavioral Assessment GDS (B6)
- NACC UDS Evaluation Form – MMSE & Neuropsychological Battery (C1)
- NACC UDS Clinician Diagnosis – Cognitive Status & Dementia (D1)
- NACC UDS Evaluation – Imaging & Labs (E1)
- UCI Neurologist Diagnosis
The Neuropathology Core at the UCI ADRC collects autopsy data and pathology-based diagnoses on multiple cohorts of subjects including patients enrolled in the ADRC clinical cohort, patients enrolled in the 90+ Study, and community cases not previously seen at the UCI ADRC. The tables below summarize the neuropathology database.
Below are links to the contents of the standard analysis files for the clinical and neuropathology datasets. These PDFs contain the variable names and formatting labels used to stored the data in the ADRC data archive. When requesting ADRC please use these variable names. When deciding upon which variables to request, it may be useful to refer to the actual data collection forms provided above.