Measurement, as a word, is the assignment of numbers to objects or events. It is a cornerstone for technology, economics, and social sciences and must be part a of the medical discipline as well. Lord Kelvin emphasized 13 decades ago (in 1883): “When you can measure what you are speaking about and express it in numbers, you know something about it” . It is also essential that measurements are as accurate as possible and include all that account. However, health is a multidimensional, subjective, and qualitatively natured concept that is usually expressed in terms of presence or absence of life-threatening illness (damage, physical disability), risk factors for mortality, activity and severity of disease, and overall health-related performance (satisfactory social functioning and emotional well-being). Thus, an accurate measurement of health status is a real challenge currently achieved only by a combination of multiple scoring tools.