Dr. Cai is an Emeritus Consulant in the Department of Developing Psychiatry at the Institute of Mental Health (IMH), Singapore since 2014. He was conferreed the life Life Long Achievement award by the Academy of Medicine, Singapore in October 2025. He has written several books. He co-authored ""Help Your Child to Cope-Understanding Childhood Stress” (1998), and ""Raise Your Child Right-A Parenting Guide for 0-6 Years"" (2002), both published by Times Editions International. “Health Wise”, a series of Health Education Textbooks for Primary School Children, published by Federal Publications, 2001. In 2003, he wrote “Living with ADHD”. This is a book on Attention Deficit Hyperactivity Disorder; published by Times Editions International. In 2005, he wrote “When Parents Fight, The Children Cry” and published by the Hope Story Publishers.  He co-edited and contributed a number of chapters in the book-A Primer of Child and Adolescent Psychiatry–which was published by World Scientific Co Pte Ltd in 2008. 

He has also contributed numerous scientific papers in local and international journals. In his clinical practice, he has a special interest in the forensic assessment of custody and access issues of children in divorce, child physical and sexual abuse, and juvenile crimes in general.