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Related Experiment Video

Updated: Jul 6, 2026

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

Published on: April 7, 2020

Measuring melatonin in humans.

Susan Benloucif¹, Helen J Burgess, Elizabeth B Klerman

¹Department of Neurology, Northwestern University Medical School, Chicago, IL, USA. sbenloucif@gmail.com

Journal of Clinical Sleep Medicine : JCSM : Official Publication of the American Academy of Sleep Medicine

|March 21, 2008

Summary

This study offers guidelines for measuring melatonin in urine, saliva, and plasma to help researchers compare data. It recommends standardized methods for consistent results across studies.

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Last Updated: Jul 6, 2026

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

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Published on: April 7, 2020

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Through-the-Wall Blood Sampling Method to Minimize Sleep Disruption in Clinical Settings

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Published on: June 13, 2025

Area of Science:

Biochemistry
Chronobiology
Clinical Research

Background:

Melatonin is a crucial hormone regulating circadian rhythms.
Standardized methods for melatonin measurement are lacking, hindering data comparability.

Purpose of the Study:

To establish guidelines for collecting and analyzing melatonin in urinary, salivary, and plasma samples.
To aid clinicians and researchers in selecting appropriate melatonin measurement techniques.
To facilitate inter-laboratory comparison of melatonin data.

Main Methods:

A modified RAND process was employed to develop consensus-based recommendations.
Guidelines cover sample collection and analysis in various settings (natural, clinical, controlled).

Main Results:

Consensus-based guidelines for melatonin measurement are presented.
Recommendations address different study environments and conditions.

Conclusions:

Current melatonin analysis methods have limitations, preventing a single universal approach.
Standardized reporting of low threshold measures of dim light melatonin onset is recommended for comparability.