{
    "age": {
        "Description": "Age of the participant",
        "Units": "years"
    },
    "sex": {
        "Description": "Biological sex of the participant",
        "Levels": {
            "M": "male",
            "F": "female"
        }
    },
    "site": {
        "Description": "Assessment site"
    },
    "family": {
        "Description": "Identifier of the participant's family"
    },
    "language": {
        "Description": "Participant's mother-tongue"
    }
}