Debbie has over 50 peer reviewed publications, published two books and numerous chapters.

Themes of her research include:

• Investigations of speech and the timing of surgery in the unoperated and late operated cleft lip and palate subject within the Sri Lankan Cleft Lip and Palate Project.
• The delivery of speech and language therapy in the Developing World for patients with cleft lip and palate.
• The development of appropriate training courses in speech and language therapy in Sri Lanka.
• Multicentre international study of speech outcome in patients with unilateral cleft lip and palate in Northern Europe(eg Eurocleft Study)
• Comparison of surgical speech outcomes in cleft palate across 2 international units: Gothenburg and North Thames Regional Cleft Lip and Palate Centre
• UK national study of speech outcome in patients between 5-6 years and 10-11 years of age with unilateral cleft lip and palate in collaboration with the Royal College of Surgeons.
• The management of velopharyngeal dysfunction, including the evaluation of different surgical protocols and prosthetic approaches
• Submucous cleft palate
• The effects of osteotomy on speech and velopharyngeal function.
• The evaluation of cleft palate speech (GOSSPASS, CAPSA, UPS).