{
    "participant_id": {
        "Description": "Unique participant identifier"
    },
    "age": {
        "Description": "Age of the participant at time of testing",
        "Units": "years"
    },
    "sex": {
        "Description": "Sex of the participant",
        "Levels": {
            "F": "female",
            "M": "male",
            "O": "other"
        }
    }
}