PPG Diary Pilot 1 Study Data
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Overview
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The data from the PPG Diary Pilot Study are available at:
       https://doi.org/10.5281/zenodo.3268500

The main data file is "ppg_diary_pilot_conv_data.mat" - a Matlab file.

The methods used to collect the data are reported in:
       Charlton P. H. et al., "Acquiring wearable photoplethysmography
       data in daily life: the PPG Diary Pilot Study", [under review]

The data analysis reported in this publication can be reproduced using the "ppg_diary_pilot1_analysis.m" Matlab script, which is available at the DOI above. The original analysis was conducted using Matlab R2020a.

Further details of the PPG Diary study are available at: https://peterhcharlton.github.io/ppg-diary

Details of data file
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The "ppg_diary_pilot_conv_data.mat" data file contains two variables:
 - data : a structure containing data recorded from the wearable PPG sensor
 - adl_data : a structure containing participant-reported activities of daily living

The "data" variable contains:
 - fs : the sampling frequency of PPG signals (100 Hz)
 - pr : the pulse rate (in beats per minute) provided by the device (at 1 Hz, see
t_sec_rel for associated times)
 - spo2 : the arterial blood oxygen saturation (in %) provided by the device (at 1 Hz, see t_sec_rel for associated times)
 - spo2_status : provided by the device (at 1 Hz, see t_sec_rel for associated times)
 - ppg_red : a vector of red PPG values (at 100 Hz, see t_ms_rel for associated times)
 - ppg_ir : a vector of infrared PPG values (at 100 Hz, see t_ms_rel for associated times)
 - perf : perfusion parameter provided by the device (at 1 Hz, see t_sec_rel for associated times)
 - t_ms_rel : time in milliseconds since the start of the study
 - t_sec_rel : time in seconds since the start of the study

The "adl_data" variable contains a list of activities of daily living (and sensor maintenance issues) and their associated times:
 - act : a list of activities and sensor maintenance issues. The suffix "_fin" indicates the end of an activity.
 - t_ms_rel : the time in milliseconds since the start of the study.

Version
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This README accompanies version 0.1 of the script, 16th Oct 2020.