Table 1.
Selection of commercial and scientific tools for circadian clock assessment in humans. *Sleep recommendations.
| BODYCLOCK®Hairtest | Geneplanet®* | Cerascreen®Melatonin Test | Salimetrics®Salivary DLMO profile (54) | WEARABLES/mobile phone apps**(55) | Munich ChronoType Questionnaire (MCTQ) (15) | |
|---|---|---|---|---|---|---|
| Sample material/method | Hair follicle (at least 15) | Saliva | Saliva | 7 saliva samples | Light reflection, spatial acceleration, electric conductance, | Questionnaire |
| Sampling protocol | Invasive, single time point | Single time point | Single time point | Non-invasive, multiple time points (within 7 h) | Triggered/interleaved/continues | Review of last four weeks |
| Target analyte | mRNA expression level | Genomic DNA Gene Variants | Hormone concentration (Melatonin) | Hormone concentration (Melatonin) | Temperature, blood pressure, heart rate, blood oxygenation, respiratory rate, acceleration, and derived measures | Not applicable |
| Result | Qualitative determination of a chronotype based on gene expression (Note: mRNA values not provided) | Qualitative lifestyle predictions based on gene variants | Quantitative measurements of melatonin concentration from saliva over time | Quantitative measurements of melatonin concentration from saliva over time | Quantitative and/or qualitative measurements of sleep-wake pattern, activity patters | Qualitative determination of Chronotype based on the query |
| Risk/Pain of procedure | None/Somewhat painful | None/None | None/None | None/None | None/None | None/None |
| Legal status | Lifestyle product | GDPR compliant and ISO 27,001 certified | DIN EN ISO 13,485, EC declarations of conformity & interlaboratory test | Research use only | Lifestyle product, medical devices | Research use only |
| Customer benefit | Generic recommendations with respect to the chronotype | Recommendations regarding sports, nutrition, stress, and sleep/determination of chronotype | Generic recommendations for action and approaches for proper nutrition | Determining DLMO is relevant in diagnosing CR-related sleep issues | Visualization of diverse body parameters for various purposes | Estimation of chronotype mainly for research use |
**
e.g., rings (Oura), bands (Halo, WHOOP, Fitbit), watches (Withings, Apple, Garmin).