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Researcher's Guide

About the UCI ADRC Researcher’s Guide

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 Neuroimaging
Jump to Description of the neuropathology database
Jump to Contents of Standard Analysis Files

ADRC Standard Analysis Files (SAFs)

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.

Data collection forms

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. The UCI Memory Assessment Clinic Forms linked below contain other instruments not included within the NACC Uniform Data Set (UDS). These other instruments include the Dementia Severity Rating Scale (DSRS), Bristol Activities of Daily Living Scale (BADLS), a Mobility Questionnaire, a subject Sleep Scale from the Measuring Functioning and Well-being: The Medical Outcomes Study Approach, and a service utilization questionnaire. PDF copies of each of the ADRC data collection forms can be obtained from the links below. Please Contact Us for the password to view the PDF file.

Neuropsychological testing
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 in the Neuropsychological Testing section provides 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.

Description of the longitudinal cohort

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.  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 on the Longitudinal Cohort section. 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 Longitudinal Cohort section.

Data completeness as reported by the National Alzheimer’s Coordinating Center

The Data Completeness section yields basic descriptive statistics on the clinical cohort as reported by the National Alzheimer’s Coordinating Center (NACC). 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.

Clinical characteristics of the longitudinal cohort

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.

Please click on the following link for the full longitudinal cohort summary measures.


Available for download are group level outputs of MRI scans in Freesurfer format with in different hemispheres (lh, rh), with different measures (area, volume, thickness), or with different atlases (default vs. DKT). Full output for individual subjects and outputs from ANTS’ cortical thickness and Mindboggle are available upon request. Please Contact Us for the password extract the outputs.

Freesurfer group level outputs

Description of the neuropathology database

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.

Contents of Standard Analysis Files (SAFs)

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.

Clinical data

Neuropath data

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updated 2021-01-19