His PhD thesis was entitled "A Study of the Cloze Procedure with Native and Non-Native Speakers of English", supervised by Dr Alan Davies.
On 19 April 2017, Alderson along with Tineke Brunfaut, and Luke Harding were selected as the winner of the International Language Testing Association (ILTA) Best Article Award.
The award-winning paper, Towards a Theory of Diagnosis in Second and Foreign Language Assessment: Insights from Professional Practice Across Diverse Fields, was published in 2015 in the journal Applied Linguistics.
The study investigated how diagnosis is theorized and carried out across a diverse range of professions with a view to finding commonalities that can be applied to the context of second and foreign language assessment.
On the basis of interviews with professionals from fields such as car mechanics, IT systems support, medicine, psychology and education, a set of principles was drawn up to facilitate inform a comprehensive theory of diagnostic assessment in a second or foreign language.