# Cold Face Test Data
## Overview
This repository contains data collected during the "Cold Face Test" Study in November 2019.
The data in this repository are used for the following projects:
* Paper [Vagus Activation by Cold Face Test Reduces Acute Psychosocial Stress Responses](https://www.nature.com/articles/s41598-022-23222-9), published in *Scientific Reports*.
## Changelog
### v1.1.0 (2023-04-04)
* Corrected error in questionnaire data - conditions for VP17, VP18, VP19, VP20 were mixed up:
*WRONG*: VP17 CFT, VP18 Control, VP19 CFT, VP20 Control
*CORRECT*: VP17 Control, VP18 CFT, VP19 Control, VP20 CFT
NOTE: This only affects the outcomes of the questionnaire analyses, NOT the outcomes of HR(V) and cortisol! Conditions for these data were assigned based on the file ``condition_list.csv`` in which the conditions were entered correctly.
### v1.0.0 (2022-03-08)
* Initial release
## How to Work with the Data
### Download from OSF
The easiest way to get the dataset is to download the dataset from [OSF](https://osf.io/8fb6n/).
### Install the CFT Analysis Package (optional)
If you want to use this dataset it is recommended to install the [`cft-analysis`](https://github.com/mad-lab-fau/cft-analysis) package. This package contains various helper functions to work with the dataset (including [`tpcp`](https://github.com/mad-lab-fau/tpcp) `Dataset` representations), process data, and different analysis experiments performed with the dataset.
See the [`cft-analysis`](https://github.com/mad-lab-fau/cft-analysis) package for further information.
## How the Data are Structured
The repository is structured as follows:
```bash
├── documents/
│ └── codebook_unipark.xlsx # Export of questionnaire project from Unipark
├── ecg/ # ECG data stuctured in separate subfolders per participant
│ ├── Vp01/
│ │ ├── raw/
│ │ │ ├── NilsPodX-<sensor-id>_YYYYMMDD_HHMMSS.bin # Raw sensor data as binary file for each individual phase
│ │ │ └── ...
│ │ └── processed/
│ │ ├── hr_result_Vp01.xlsx # Heart rate extracted from raw ECG data
│ │ ├── hrv_continuous_Vp01.xlsx # Continuous heart rate variability extracted from ECG data (window size: 10 samples, overlap: 1 sample)
│ │ └── rpeaks_result_Vp01.xlsx # R peaks (indices and RR intervals) extracted from raw ECG data
│ ├── Vp02/
│ └── .../
├── questionnaire/ # Questionnaire data stored as tabular data
│ ├── cleaned/
│ │ └── questionnaire_data_cleaned.xlsx # Questionnaire data cleaned after export from Unipark
│ ├── processed/
│ │ └── questionnaire_data.csv # Processed questionnaire data with computed scores
│ └── codebook.csv # Codebook with mapping of nominal and ordinal scales to numerical values
├── saliva/ # Saliva data stored as tabular data
│ ├── raw/
│ │ ├── cft_amylase_data.xlsx # Alpha-amylase in raw data format
│ │ └── cft_cortisol_data.xlsx # Cortisol in raw data format
│ └── processed/
│ ├── cortisol_samples.csv # Cortisol raw samples in long-format
│ └── cortisol_features.csv # Computed cortisol features in long-format
└── condition_list.csv # Mapping of Subject ID and Condition
```
### What Data are Missing
No data are missing in this dataset, however, for some participants (e.g., `Vp01` and `Vp06`) sensor data for some phases were accidentally recorded as `.csv` files instead of `.bin` files. Thus, to facilitate data import it is recommended to load the data folder of one subject via the helper function provided in the [`cft-analysis`](https://github.com/mad-lab-fau/cft-analysis) package: `cft_analysis.datasets.helper.load_ecg_raw_data_folder()`.
## How the Data were Acquired
In this study, 28 healthy participants were exposed to acute stress by the Montreal Imaging Stress Task (MIST) while ECG, salivary cortisol, and self-reported were recorded.
The study took place on several days between 11:00 a.m. - 5:30 p.m. Individuals were randomly assigned to either the Control group or the group that was exposed to the CFT. The following data were collected for each participant:
* **ECG**: 1-channel ECG according to Lead I of Einthoven's triangle using a wearable sensor node (Portabiles GmbH, Erlangen, Germany), split into the following phases:
* *Pre* (also denoted as *Global Baseline*): duration ~15 min
* *MIST Phase 1*: duration ~10 min
* *MIST Phase 2*: duration ~10 min
* *MIST Phase 3*: duration ~10 min
* *Post*: duration ~45 min
Each *MIST* phase was further divided into the following subphases:
* Baseline (BL): duration 60s
* Resting Period / Cold Face Intervention (RP/CFI): duration 120s
* Arithmetic Tasks (AT): duration 240s
* Feedback (FB): variable duration
* **Saliva**: During the study a total of seven saliva samples (S0-S6) were collected along with the study procedure -30, 0, 30, 40, 50, 60, 70 min relative to MIST start. S0 was only collected to scan for (and possibly exclude) individuals with high cortisol baseline levels while S1-S6 were used for further analysis.
* **Self-Reports**: Self-reports, assessed via questionnaire, were assessed before (pre) and after (post) the MIST. To assess mood state the "Multidimensionale Befindlichkeitsfragebogen" (MDBF), the German version of the "Mood State Questionnaire", was used.