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This individual's Irritability is generally lowest after a daily total of 72 minutes of REM Sleep Duration over the previous 24 hours.
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Blue represents the sum of REM Sleep Duration over the previous 24 hours
An increase in 24 hours cumulative REM Sleep Duration is usually followed by an increase in Irritability. (R = 0.112)
Typical values for Irritability following a given amount of REM Sleep Duration over the previous 24 hours.
Typical REM Sleep Duration seen over the previous 24 hours preceding the given Irritability value.
This chart shows how your REM Sleep Duration changes over time.
Each column represents the number of days this value occurred.
This chart shows the typical value recorded for REM Sleep Duration on each day of the week.
This chart shows the typical value recorded for REM Sleep Duration for each month of the year.
This chart shows how your Irritability changes over time.
Each column represents the number of days this value occurred.
This chart shows the typical value recorded for Irritability on each day of the week.
This chart shows the typical value recorded for Irritability for each month of the year.

Abstract

This individual's Irritability is generally 4% lower than normal after 72 minutes REM Sleep Duration per 24 hours. This individual's data suggests with a medium degree of confidence (p=0.11980957020669, 95% CI -0.096 to 0.32) that REM Sleep Duration has a weakly positive predictive relationship (R=0.11) with Irritability. The highest quartile of Irritability measurements were observed following an average 84 minutes REM Sleep Duration per day. The lowest quartile of Irritability measurements were observed following an average 72.75 min REM Sleep Duration per day.Irritability is generally 4% lower than normal after a total of 73 minutes of REM Sleep Duration over the previous 24 hours. Irritability is generally 5% higher after a total of 84 minutes of REM Sleep Duration over the previous 24 hours.

Objective

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

Participant Instructions

Get Fitbit here and use it to record your REM Sleep Duration. 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.
Record your Irritability daily in the reminder inbox or using the interactive web or mobile notifications.

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

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

Irritability Pre-Processing
Irritability measurement values below 1 out of 5 were assumed erroneous and removed. Irritability measurement values above 5 out of 5 were assumed erroneous and removed. No missing data filling value was defined for Irritability so any gaps in data were just not analyzed instead of assuming zero values for those times.
Irritability Analysis Settings

Predictive Analytics
It was assumed that 0 hours would pass before a change in REM Sleep Duration would produce an observable change in Irritability. It was assumed that REM Sleep Duration could produce an observable change in Irritability for as much as 1 days after the stimulus event.
Predictive Analysis Settings

Data Quantity
314 raw REM Sleep Duration measurements with 290 changes spanning 332 days from 2018-05-06 to 2019-04-03 were used in this analysis. 217 raw Irritability measurements with 102 changes spanning 1961 days from 2013-11-17 to 2019-04-02 were used in this analysis.

Data Sources

REM Sleep Duration data was primarily collected using Fitbit. Fitbit makes activity tracking easy and automatic.

Irritability 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.

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 weakly positive relationship between REM Sleep Duration and Irritability

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. 181 paired data points were used in this analysis. Assuming that the relationship is merely coincidental, as the participant independently modifies their REM Sleep Duration 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 REM Sleep Duration and Irritability 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 REM Sleep Duration
Effect Variable Name Irritability
Sinn Predictive Coefficient 0.1113
Confidence Level medium
Confidence Interval 0.20819390105644
Forward Pearson Correlation Coefficient 0.112
Critical T Value 1.646
Total REM Sleep Duration Over Previous 24 hours Before ABOVE Average Irritability 84 minutes
Total REM Sleep Duration Over Previous 24 hours Before BELOW Average Irritability 73 minutes
Duration of Action 24 hours
Effect Size weakly positive
Number of Paired Measurements 181
Optimal Pearson Product 0.040687413433742
P Value 0.11980957020669
Statistical Significance 0.994
Strength of Relationship 0.20819390105644
Study Type individual
Analysis Performed At 2019-04-04

REM Sleep Duration Statistics

Property Value
Variable Name REM Sleep Duration
Aggregation Method SUM
Analysis Performed At 2019-04-03
Duration of Action 24 hours
Kurtosis 3.1877848056985
Maximum Allowed Value 7 days
Mean 78 minutes
Median 74 minutes
Minimum Allowed Value 60 seconds
Number of Changes 290
Number of Correlations 1
Number of Measurements 314
Onset Delay 0 seconds
Standard Deviation 33.196219964213
Unit Minutes
Variable ID 6054281
Variance 1101.9890199124

Irritability Statistics

Property Value
Variable Name Irritability
Aggregation Method MEAN
Analysis Performed At 2019-04-03
Duration of Action 24 hours
Kurtosis 2.9569683721335
Maximum Allowed Value 5 out of 5
Mean 2.3886 out of 5
Median 2 out of 5
Minimum Allowed Value 1 out of 5
Number of Changes 102
Number of Correlations 1039
Number of Measurements 217
Onset Delay 0 seconds
Standard Deviation 0.92180237350395
Unit 1 to 5 Rating
Variable ID 1358
Variance 0.84971961579751

Tracking REM Sleep Duration

Get Fitbit here and use it to record your REM Sleep Duration. 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.

Tracking Irritability

Record your Irritability daily in the reminder inbox or using the interactive web or mobile notifications.
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https://lh6.googleusercontent.com/-BHr4hyUWqZU/AAAAAAAAAAI/AAAAAAAIG28/2Lv0en738II/photo.jpg Principal Investigator - Mike Sinn