Medically reviewed & verified by: Prof. Dr. Naci Karacaoglan
Written by: ClinicAdvisor®
In the 1950s, James B. Hamilton, an American professor of medicine specializing in anatomy and one of the leading experts on baldness at the time, developed a "scale of baldness."
This scale helps diagnose the progress of hereditary hair loss in men (aka Androgenetic Alopecia or male pattern baldness).
Afterward, in the mid-1970s, Doctor O'Tar Norwood developed Dr. Hamilton's scale by making some improvements and additions.
This led to the Norwood - Hamilton scale, which is still widely used today and is outlined in the image below.
The Norwood - Hamilton scale is still a popular tool used to classify the level of androgenetic alopecia, but there is no universal consensus on its reliability.
A study (published here) has shown that submitting some patients suffering from androgenetic alopecia to various expert doctors did not lead to a univocal classification of individual cases.
What is Norwood-Hamilton Classification?
This Norwood Scale, represented by a series of relatively clear and explanatory images, marks the progress of baldness in 7 phases that can be quantitatively described as follows:
These pictures outline the Norwood classification, which has seven levels ranging from minimal alopecia to baldness (total hair loss).
Is the Norwood Scale accurate?
Let's look at the big picture: what is the use of "classifying" the level of alopecia?
Discovering that you are at level II, for example, risks being just an act for its own sake. The surgeon, having dealt with thousands of cases in the course of his professional experience, will be able to determine the actual state of progress of the hair loss.
The surgeon makes his diagnosis based on a complete medical history, the objective examination of the quality of the follicles (okay, thick, curly, light, dark, etc.), and the general state of health of the patient and his age to improve the overall result as much as possible even in the long term.
For example, the same level of baldness can be found in two people, but if one is 25 years old and the other over 55. They are two patients who will need very different treatments.
What is the importance of an accurate diagnosis?
Intervening at the right time and, above all, highlighting to the patient how the evolution of the problem will be.
Equally important is that diagnosis provide an evaluation and planning of the necessary hair transplant sessions to obtain lasting results that ensure the patient an aesthetically pleasing and natural development in a permanent manner.
Here the assessment of the degree of baldness is also helpful to provide the patient with a clear picture of the possibilities of correction and to understand if what the surgeon can do for him is what he expects.