A PhD stands for Doctor of Philosophy and is generally viewed globally as the pinnacle of academic achievement in any field of study. On the other hand, an MD stands for Doctor of Medicine but generally has fewer requirements to obtain than a PhD. It is possible to obtain both an MD and a PhD in medicine.
Strictly speaking, the word “Doctor” is Latin for “Teacher” which came before the modern use of the word “Doctor” to describe practising physicians. You can and should use the title “Doctor” to address and refer to those with PhDs. You normally would not use both the title and the qualification together, i.e. Dr. Joe Bloggs PhD. But using either Dr. Bloggs or Joe Bloggs PhD are both within acceptable norm. Although we may have more fond names that we call these individuals in our close family society, it is important to recognize hard earned achievements by our people.
To consciously do otherwise, when the context and protocol require it, belittles that achievement, that degree, and the institution that conferred the degree in addition to the person himself/herself.
Let us encourage advanced education, rather than belittle it, and encourage our children towards greater achievement. To all those Cook Islanders with advanced degrees, I say well done! To those still working on advanced degrees, I say keep going!