Sometimes multiple works with three or more authors and the same publication year shorten to the same in-text citation form, which creates ambiguity.
To avoid ambiguity, when the in-text citations of multiple works with three or more authors shorten to the same form, write out as many names as needed to distinguish the references, and abbreviate the rest of the names to “et al.” in every citation.
For example, if these two sources were cited in the same paper, three author surnames would be shown in each case before the rest of the surnames are abbreviated to “et al.”:
Kapoor, Bloom, Montez, et al. (2017)
Kapoor, Bloom, Zucker, et al. (2017)
Citing multiple works with three or more authors and the same publication year is covered in Section 8.18 of the APA Publication Manual, Seventh Edition
This guidance is the same as in the 6th edition.
Because “et al.” is plural (meaning “and others”), it cannot stand for only one name. In cases where only the final author is different, spell out all names in every citation:
Hasan, Liang, Kahn, and Jones-Miller (2015)
Hasan, Liang, Kahn, and Weintraub (2015)