An extension in terms of

-summable (valuated) groups for a cofinal with

ordinal

of the classical Dieudonné criterion
(Portugaliae Mathematicae, 1952), concerning the direct sums of

-primary cyclic groups, is established. Specifically, it is
proved that if

is an abelian

-group whose length

is cofinal with

and if

is a subgroup of

so that

is a

-summable valuated group using the
valuation inherited from the height valuation on

and so that

is a

-summable group, then

is a

-summable group.