3
                endogenous
            and illness onset
                d
                2 a
                b
          super a b
             an
                c
                6
           know c long
                c
                5 a
              i maintenance
                depressions i e
      advantage disorder e
                a short b
            ash b

                c

                1 reduction
            gem short
              a a
              a d long 4
                b