In collaboration with Alison Hipwell, Frits Goossens, and R. Kumar, Melhuish carried out a research study to assess disruption in child-mother interactions at one-year
postpartum, illustrating that infants with depressed mothers are more likely to experience severe attachment risks. Moreover, he reported that parental
opioid usage also negatively influences children's physical and neurocognitive development. Melhuish reported the association between preschool programs and
cognitive development, and the interconnectedness among teacher and child interactions and shared thinking. He studied the interdependence between preschool attendance and socio-economic backgrounds. He highlighted that academic under-achievements are associated with children's development and experiences during the starting years of their schooling. He also stated that the assessment of the home-learning environment indicated numeracy achievement among five-year-old children. In 2006, Melhuish co-edited a book titled
Early Childhood Care and Education: International Perspectives, in which he investigated how early childhood programs are being addressed in various nations and how they impact young children's experiences and development. Pamela Oberhuemer characterized it as a "valuable collection of papers" and stated that it provided a "fascinating overview" of policies and research findings. Joseph Di Bona commented that this write-up has "inevitable unevenness" because of involving a dozen authors. Additionally, he co-edited another book,
The National Evaluation of Sure Start: Does Area-Based Early Intervention Work?, in which he examined the development of child health and welfare programs for Sure Start, highlighted the differences between the expected and actual performance of Sure Start Local Programmers (SSLPs) in terms of costs, strengths, and shortcomings. Reviewing the book, Gillian Brid wrote that each chapter contains a "robust, well-referenced, and detailed analysis" of the various aspects of the SSL. In
Early Childhood Matters: Evidence from the Effective Pre-school and Primary Education Project, Melhuish documented how early childhood education and care advanced significantly between the late 1990s and the start of the new millennium, primarily emphasizing the role of the Effective Pre-School and Primary Education (EPPE) project in this regards. The book was reviewed by Naomi Eisenstadt, a senior research fellow at Oxford University, who stated that "anyone who has worked in Britain over the last 10 years in the field of early education and care will, whether they know it or not, have been influenced by EPPE. Indeed, many people currently employed in early years’ services owe the fact of their employment at least in part to the findings from this remarkable research". However, she also noted that it had little reference to pre-Labour policy framework and found it to be a "bit disjointed". ==Awards and honors==