The description of DOAJ is " DOAJ is a community-curated online directory that indexes and provides access to high quality, open access, peer-reviewed journals."
However, not all journals indexed in DOAJ are of high quality, have an impact factor, or are widely read in the scientific community. One has to consider other factors to determine if a journal indexed in DOAJ meets the requirements of best practices in scientific publishing.
It is a good idea to evaluate the journal against the criteria mentioned at http://thinkchecksubmit.org/