For checkboxes, if triple state is set to NO, the checkbox will never be null. It is always TRUE or FALSE. For that case, you simply set its visible property this way
Me.chkMyCheckBox.Visible = Me.chkMyCheckBox
If the checkbox is TRUE, Me.chkMyCheckBox is TRUE, and the visible property is set to TRUE. If false, the checkbox will disappear. Use your real checkbox name(s).
Michigan Dept. of Environmental Quality, Air Quality Division