Dyadic Hair Cortisol Self-Collection Procedure

At-home self-collection of specimens has become more commonplace because of measures taken in response to the coronavirus pandemic. Self-collection of hair cortisol is important because chronic stress is present in many populations, such as older adults living with Alzheimer's disease and their family caregivers. For the evaluation of chronic stress, scalp hair can be used as a predictive biomarker because it examines the cumulative, retrospective stress from previous months.

The aim of the paper is to provide a study procedure for at-home, scalp hair self-collection for cortisol concentration analysis from dyads consisting of a person living with Alzheimer's disease and their family caregiver.

After informed electronic consent is obtained, a package containing the necessary tools for self-collection of hair samples from the dyad is mailed to the participant's home. Participants are provided detailed print and video multimedia guides outlining how to obtain the hair samples. Ideally, the hair samples are obtained during the virtual data collection meeting with research personnel. Participants mail back the hair sample in a prepaid package to the biomedical laboratory for analysis.

At-home, self-collection of hair provides potential advantages such as reduced participant burden, especially for vulnerable populations where transportation and different environments are challenging. At-home sample collection options may increase research participation and can be applied to multiple research foci. Research considerations for dyads, such as people living with Alzheimer's disease and their caregivers, are discussed.