function $(id)
{
    return document.getElementById(id);
}

function Z() {};

Z.show = function(id)
{
    var x = $(id);
    x.style.display = 'block';
    x.style.visibility = 'visible';

    return false;
}

Z.hide = function(id)
{
    var x = $(id);
    x.style.display = 'none';
    x.style.visibility = 'hidden';

    return false;
}

Z.isVisible = function(id)
{
    var x = $(id);

    return !(x.style.display == 'none' || x.style.display == '')
}

Z.toggle = function(id)
{
    if (Z.isVisible(id)) return Z.hide(id);
	 if (frailty2.isVisible(id)) return frailty2.hide(id);
    return Z.show(id);
}