ACT Statistical Guidance
Resources
Here are some commonly used ACT study resources.
References for study design and cohort description.
This landmark study by Kukall et al. 2002 is one of the first published papers to describe the ACT Cohort. This paper provides a description of the key ACT study design elements and provides an early description of dementia and Alzheimer's disease (AD) in this cohort. This paper is commonly used as a reference for the ACT study in peer-reviewed manuscripts. ACT study participants are dementia-free indivdiuals aged 65 and over selected from the Kaiser Permanente Washington (KPWA) members. Consequently, a rich set of electronic health records data are available on ACT participants, as described here. While ACT participants need to be members of KPWA at study enrollment, after enrollment, ACT participants may continue on the ACT study regardless of whether they remain in KPWA.
Information regarding ACT dementia outcome
Kukall et al. 2002 provides a description of participant follow-up and the screening process in the ACT Study for the dementia outcome. The ACT dementia outcome is based on a consensus diagnosis for dementia cases that meet Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria. Possible/probable Alzheimer's disease (AD) defined by the NINCDS-ADRDA criteria is also available in the ACT study data. Biennial followup is continued on subjects until they meet the ACT study dementia outcome (even if diagnosed with possible/probable AD according to NINCDS-ADRDA). The convention in ACT is to assign the event time for dementia or time to first of dementia or possible/probable AD as the mid-point between the biennial visit that triggered the evaluation/dementia diagnosis and the previous visit. Sample papers that have used this midpoint analysis are Gray et al. 2019 and Marcum et al. 2019.
ACT Study data
The ACT Data repository, which includes descriptions of the available data element, a data query tool, study forms, and other related documentation is available here
Collaboration
The ACT Publication policy and request process for study data and ancillary studies, as well as other forms of collaboration, are available here.
For more information regarding the ACT study and available resources visit https://www.ACTagingresearch.org.
