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This individual's Sleep Start Time is generally highest after a daily total of 0 milligrams of Melatonin intake over the previous 24 hours.
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Blue represents the sum of Melatonin intake over the previous 24 hours
An increase in 24 hours cumulative Melatonin intake is usually followed by an decrease in Sleep Start Time. (R = -0.028)
Typical values for Sleep Start Time following a given amount of Melatonin intake over the previous 24 hours.
Typical Melatonin intake seen over the previous 24 hours preceding the given Sleep Start Time value.
This chart shows how your Melatonin changes over time.
Each column represents the number of days this value occurred.
This chart shows the typical value recorded for Melatonin on each day of the week.
This chart shows the typical value recorded for Melatonin for each month of the year.
This chart shows how your Sleep Start Time changes over time.
Each column represents the number of days this value occurred.
This chart shows the typical value recorded for Sleep Start Time on each day of the week.
This chart shows the typical value recorded for Sleep Start Time for each month of the year.

Abstract

This individual's Sleep Start Time is generally 0% higher than normal after a total of 0 milligrams Melatonin intake over the previous 24 hours. This individual's data suggests with a high degree of confidence (p=0.1041917114614, 95% CI -0.2 to 0.144) that Melatonin (mg) has a very weakly negative predictive relationship (R=-0.03) with Sleep Start Time. The highest quartile of Sleep Start Time measurements were observed following an average 0.08 milligrams Melatonin (mg) per day. The lowest quartile of Sleep Start Time measurements were observed following an average 0.2287104622871 mg Melatonin (mg) per day.Sleep Start Time is generally 1% lower than normal after a total of 0.2287104622871 milligrams of Melatonin intake over the previous 24 hours. Sleep Start Time is generally 0% higher after a total of 0.08 milligrams of Melatonin intake over the previous 24 hours.

Objective

The objective of this study is to determine the nature of the relationship (if any) between Melatonin and Sleep Start Time. Additionally, we attempt to determine the Melatonin (mg) values most likely to produce optimal Sleep Start Time values.

Participant Instructions

Record your Melatonin daily in the reminder inbox or using the interactive web or mobile notifications.
Get Fitbit here and use it to record your Sleep Start Time. Once you have a Fitbit account, you can import your data from the Import Data page. This individual's data will automatically be imported and analyzed.

Design

This study is based on data donated by one participant. Thus, the study design is consistent with an n=1 observational natural experiment.

Data Analysis

Melatonin Pre-Processing
Melatonin measurement values below 0 milligrams were assumed erroneous and removed. No maximum allowed measurement value was defined for Melatonin. It was assumed that any gaps in Melatonin data were unrecorded 0 milligrams measurement values.
Melatonin Analysis Settings

Sleep Start Time Pre-Processing
Sleep Start Time measurement values below 60 minutes were assumed erroneous and removed. Sleep Start Time measurement values above 7 days were assumed erroneous and removed. No missing data filling value was defined for Sleep Start Time so any gaps in data were just not analyzed instead of assuming zero values for those times.
Sleep Start Time Analysis Settings

Predictive Analytics
It was assumed that 0.5 hours would pass before a change in Melatonin (mg) would produce an observable change in Sleep Start Time. It was assumed that Melatonin (mg) could produce an observable change in Sleep Start Time for as much as 1 days after the stimulus event.
Predictive Analysis Settings

Data Quantity
413 raw Melatonin (mg) measurements with 198 changes spanning 2483 days from 2012-06-13 to 2019-04-02 were used in this analysis. 1955 raw Sleep Start Time measurements with 1171 changes spanning 1954 days from 2013-11-26 to 2019-04-03 were used in this analysis.

Data Sources

Melatonin (mg) data was primarily collected using QuantiModo. QuantiModo allows you to easily track mood, symptoms, or any outcome you want to optimize in a fraction of a second. You can also import your data from over 30 other apps and devices. QuantiModo then analyzes your data to identify which hidden factors are most likely to be influencing your mood or symptoms.

Sleep Start Time data was primarily collected using Fitbit. Fitbit makes activity tracking easy and automatic.

Limitations

As with any human experiment, it was impossible to control for all potentially confounding variables. Correlation does not necessarily imply causation. We can never know for sure if one factor is definitely the cause of an outcome. However, lack of correlation definitely implies the lack of a causal relationship. Hence, we can with great confidence rule out non-existent relationships. For instance, if we discover no relationship between mood and an antidepressant this information is just as or even more valuable than the discovery that there is a relationship.
We can also take advantage of several characteristics of time series data from many subjects to infer the likelihood of a causal relationship if we do find a correlational relationship. The criteria for causation are a group of minimal conditions necessary to provide adequate evidence of a causal relationship between an incidence and a possible consequence.

The list of the criteria is as follows:
Strength (A.K.A. Effect Size)
A small association does not mean that there is not a causal effect, though the larger the association, the more likely that it is causal. There is a very weakly negative relationship between Melatonin intake and Sleep Start Time

Consistency (A.K.A. Reproducibility)
Consistent findings observed by different persons in different places with different samples strengthens the likelihood of an effect. Furthermore, in accordance with the law of large numbers (LLN), the predictive power and accuracy of these results will continually grow over time. 1786 paired data points were used in this analysis. Assuming that the relationship is merely coincidental, as the participant independently modifies their Melatonin intake values, the observed strength of the relationship will decline until it is below the threshold of significance. To it another way, in the case that we do find a spurious correlation, suggesting that banana intake improves mood for instance, one will likely increase their banana intake. Due to the fact that this correlation is spurious, it is unlikely that you will see a continued and persistent corresponding increase in mood. So over time, the spurious correlation will naturally dissipate.

Specificity
Causation is likely if a very specific population at a specific site and disease with no other likely explanation. The more specific an association between a factor and an effect is, the bigger the probability of a causal relationship.

Temporality
The effect has to occur after the cause (and if there is an expected delay between the cause and expected effect, then the effect must occur after that delay). The confidence in a causal relationship is bolstered by the fact that time-precedence was taken into account in all calculations.

Biological Gradient
Greater exposure should generally lead to greater incidence of the effect. However, in some cases, the mere presence of the factor can trigger the effect. In other cases, an inverse proportion is observed: greater exposure leads to lower incidence.

Plausibility
A plausible bio-chemical mechanism between cause and effect is critical. This is where human brains excel. Based on our responses so far, 1 humans feel that there is a plausible mechanism of action and 0 feel that any relationship observed between Melatonin intake and Sleep Start Time is coincidental.

Coherence
Coherence between epidemiological and laboratory findings increases the likelihood of an effect. It will be very enlightening to aggregate this data with the data from other participants with similar genetic, diseasomic, environmentomic, and demographic profiles.

Experiment
All of human life can be considered a natural experiment. Occasionally, it is possible to appeal to experimental evidence.

Analogy
The effect of similar factors may be considered.

Relationship Statistics

Property Value
Cause Variable Name Melatonin intake
Effect Variable Name Sleep Start Time
Sinn Predictive Coefficient 0.0258
Confidence Level high
Confidence Interval 0.17237344516352
Forward Pearson Correlation Coefficient -0.028
Critical T Value 1.646
Total Melatonin intake Over Previous 24 hours Before ABOVE Average Sleep Start Time 0.08 milligrams
Total Melatonin intake Over Previous 24 hours Before BELOW Average Sleep Start Time 0.229 milligrams
Duration of Action 24 hours
Effect Size very weakly negative
Number of Paired Measurements 1786
Optimal Pearson Product 0.0053862470153207
P Value 0.1041917114614
Statistical Significance 0.9232
Strength of Relationship 0.17237344516352
Study Type individual
Analysis Performed At 2019-04-04

Melatonin Statistics

Property Value
Variable Name Melatonin (mg)
Aggregation Method SUM
Analysis Performed At 2019-04-05
Duration of Action 24 hours
Kurtosis 22.890172491482
Mean 0.46775 milligrams
Median 0 milligrams
Minimum Allowed Value 0 milligrams
Number of Changes 198
Number of Correlations 137
Number of Measurements 413
Onset Delay 30 minutes
Standard Deviation 1.3472079978472
Unit Milligrams
UPC 047469071509
Variable ID 109172
Variance 1.8149693894633

Sleep Start Time Statistics

Property Value
Variable Name Sleep Start Time
Aggregation Method MEAN
Analysis Performed At 2019-04-05
Duration of Action 24 hours
Kurtosis 7.2125987470022
Maximum Allowed Value 7 days
Mean 12 hours
Median 12 hours
Minimum Allowed Value 60 minutes
Number of Changes 1171
Number of Correlations 3164
Number of Measurements 1955
Onset Delay 0 seconds
Standard Deviation 1.7421264575675
Unit Hours
Variable ID 5211821
Variance 3.0350045941567

Tracking Melatonin

Record your Melatonin daily in the reminder inbox or using the interactive web or mobile notifications.

Tracking Sleep Start Time

Get Fitbit here and use it to record your Sleep Start Time. Once you have a Fitbit account, you can import your data from the Import Data page. This individual's data will automatically be imported and analyzed.
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https://lh6.googleusercontent.com/-BHr4hyUWqZU/AAAAAAAAAAI/AAAAAAAIG28/2Lv0en738II/photo.jpg Principal Investigator - Mike Sinn