Fitbit Steps Intraday¶
Sensor parameters description for [FITBIT_STEPS_INTRADAY]
:
Key | Description |
---|---|
[CONTAINER] |
Container where your steps intraday data is stored, depending on the data stream you are using this can be a database table, a CSV file, etc. |
[EXCLUDE_SLEEP] |
Step data will be excluded if it was logged during sleep periods when at least one [EXCLUDE] flag is set to True . Sleep can be delimited by (1) a fixed period that repeats on every day if [TIME_BASED][EXCLUDE] is True or (2) by Fitbit summary sleep episodes if [FITBIT_BASED][EXCLUDE] is True. If both are True (3), we use all Fitbit sleep episodes as well as the time-based episodes that do not overlap with any Fitbit episodes. If [TIME_BASED][EXCLUDE] is True, make sure Fitbit sleep summary container points to a valid table or file. |
RAPIDS provider¶
Available time segments
- Available for all time segments
File Sequence
- data/raw/{pid}/fitbit_steps_intraday_raw.csv
- data/raw/{pid}/fitbit_steps_intraday_with_datetime.csv
- data/raw/{pid}/fitbit_sleep_summary_raw.csv (Only when [EXCLUDE_SLEEP][EXCLUDE]=True and [EXCLUDE_SLEEP][TYPE]=FITBIT_BASED)
- data/interim/{pid}/fitbit_steps_intraday_with_datetime_exclude_sleep.csv (Only when [EXCLUDE_SLEEP][EXCLUDE]=True)
- data/interim/{pid}/fitbit_steps_intraday_features/fitbit_steps_intraday_{language}_{provider_key}.csv
- data/processed/features/{pid}/fitbit_steps_intraday.csv
Parameters description for [FITBIT_STEPS_INTRADAY][PROVIDERS][RAPIDS]
:
Key | Description |
---|---|
[COMPUTE] |
Set to True to extract FITBIT_STEPS_INTRADAY features from the RAPIDS provider |
[FEATURES] |
Features to be computed from steps intraday data, see table below |
[REFERENCE_HOUR] |
The reference point from which firststeptime or laststeptime is to be computed, default is midnight |
[THRESHOLD_ACTIVE_BOUT] |
Every minute with Fitbit steps data wil be labelled as sedentary if its step count is below this threshold, otherwise, active . |
[THRESHOLD_DEVICE_NONWEAR_TIME] |
Number of consecutive minutes with zero step counts at or above which to label as a period of device non-wear time. Used only to calculate uncensoredmeancadence feature. Default is 1, which corresponds to a measure of mean non-zero walking cadence. Set to 60 for consistency with Tudor-Locke et al.’s definition. Set to 0 to disable. |
[THRESHOLD_MINUTE_LEVEL_STEP_COUNT] |
Rows with minute-level step counts above this threshold will be excluded from feature computation. Default is 1000; set to 0 to disable. |
[INCLUDE_ZERO_STEP_ROWS] |
Whether or not to include time segments with a 0 step count during the whole day. |
Features description for [FITBIT_STEPS_INTRADAY][PROVIDERS][RAPIDS]
:
Feature | Units | Description |
---|---|---|
sumsteps | steps | The total step count during a time segment. |
maxsteps | steps | The maximum step count during a time segment. |
minsteps | steps | The minimum step count during a time segment. |
avgsteps | steps | The average step count during a time segment. |
stdsteps | steps | The standard deviation of step count during a time segment. |
firststeptime | minutes | Minutes until the first non-zero step count. |
laststeptime | minutes | Minutes until the last non-zero step count. |
countepisodesedentarybout | bouts | Number of sedentary bouts during a time segment. |
sumdurationsedentarybout | minutes | Total duration of all sedentary bouts during a time segment. |
maxdurationsedentarybout | minutes | The maximum duration of any sedentary bout during a time segment. |
mindurationsedentarybout | minutes | The minimum duration of any sedentary bout during a time segment. |
avgdurationsedentarybout | minutes | The average duration of sedentary bouts during a time segment. |
stddurationsedentarybout | minutes | The standard deviation of the duration of sedentary bouts during a time segment. |
countepisodeactivebout | bouts | Number of active bouts during a time segment. |
sumdurationactivebout | minutes | Total duration of all active bouts during a time segment. |
maxdurationactivebout | minutes | The maximum duration of any active bout during a time segment. |
mindurationactivebout | minutes | The minimum duration of any active bout during a time segment. |
avgdurationactivebout | minutes | The average duration of active bouts during a time segment. |
stddurationactivebout | minutes | The standard deviation of the duration of active bouts during a time segment. |
activetosedentarytransitionprobability | unitless | Active-to-sedentary transition probability (ASTP). The reciprocal of the mean active bout length during a time segment. Bounded by 0 and 1. |
sumdurationactivitylessthan5minutes | minutes | Sum of duration of active bouts less than 5 minutes in length during a time segment. |
sumdurationactivity5to105minutes | minutes | Sum of duration of active bouts between 5 and 10 minutes in length, inclusive, during a time segment. |
sumdurationactivitygreaterthan10minutes | minutes | Sum of duration of active bouts more than 10 minutes in length during a time segment. |
ginicoefficient | unitless | Measure of (absolute, not squared) variability of active bout durations normalized by the average active bout duration during a time segment. When the Gini coefficient is close to 1, it indicates that total time is accumulated via a small number of longer bouts. Conversely, when the Gini coefficient is close to 0, it indicates that all bouts contribute equally to total time. |
meancadence | steps/minute | The average steps/minute during a time segment. |
uncensoredmeancadence | steps/minute | The total raw steps accumulated divided by device wear time during a time segment. |
peak1minutecadence | steps/minute | The steps/minute recorded for the highest single minute during a time segment; this is also equivalent to the maximum 1 minute cadence. |
peak30minutecadence | steps/minute | The average steps/minute recorded for the 30 highest, but not necessarily consecutive, minutes during a time segment. |
peak60minutecadence | steps/minute | The average steps/minute recorded for the 60 highest, but not necessarily consecutive, minutes during a time segment. |
max5minutecadence | steps/minute | The average steps/minute of the maximum number of steps obtained over 5 continuous minutes during a time segment. |
max20minutecadence | steps/minute | The average steps/minute of the maximum number of steps obtained over 20 continuous minutes during a time segment. |
max30minutecadence | steps/minute | The average steps/minute of the maximum number of steps obtained over 30 continuous minutes during a time segment. |
max60minutecadence | steps/minute | The average steps/minute of the maximum number of steps obtained over 60 continuous minutes during a time segment. |
totalminutes0cadence | minutes | Total minutes with no movement (0 steps/minute) during a time segment; an indicator of non-ambulatory or sedentary time. |
totalminutes1to19cadence | minutes | Total minutes with incidental movement ([1, 20) steps/minute) during a time segment. |
totalminutes20to39cadence | minutes | Total minutes with sporadic movement ([20, 40) steps/minute) during a time segment. |
totalminutes40to59cadence | minutes | Total minutes with purposeful steps ([40, 60) steps/minute) during a time segment. |
totalminutes60to79cadence | minutes | Total minutes with slow walking ([60, 80) steps/minute) during a time segment. |
totalminutes80to99cadence | minutes | Total minutes with medium walking ([80, 100) steps/minute) during a time segment. |
totalminutes100to119cadence | minutes | Total minutes with brisk walking ([100, 120) steps/minute) during a time segment. |
totalminutes120pluscadence | minutes | Total minutes with all faster ambulation ([120, Inf) steps/minute) during a time segment. |
totalminutesabove0cadence | minutes | Total minutes with any movement (>0 steps/minute) during a time segment. |
totalminutesabove19cadence | minutes | Total minutes with non-incidental movement (>19 steps/minute) during a time segment. |
totalminutesabove100cadence | minutes | Total minutes with movement of at least moderate intensity (>100 steps/minute) during a time segment; this threshold was based on findings from ostensibly health individuals without movement impairments. |
Assumptions/Observations
- Active and sedentary bouts. If the step count per minute is smaller than
THRESHOLD_ACTIVE_BOUT
(default value is 10), that minute is labelled as sedentary, otherwise, is labelled as active. Active and sedentary bouts are periods of consecutive minutes labelled asactive
orsedentary
. - Activity fragmentation features are based on the following papers: Di et al., 2017, Schrack et al., 2019, and Wanigatunga et al., 2019.
- Walking cadence features are based on the following review paper: Tudor-Locke et al., 2018.