Bare weight involves weighing a bare child. Wt is an abbreviation for Weight. Birth weight is the body weight of a baby at birth. BW is an abbreviation for either Bare weight or Birth weight, depending on context. CW is current weight.

• Smart scales are scales that have the ability to sync through WiFi with the cloud, allowing you to easily record your weight, body fat, even heart rate, air temperature and quality information. This information can then be shared with doctors to improve healthcare. Withings WS30 only does weight and BMI. Fitbit Aria also does body fat percentage. Withings WS50 also does heart rate, air temperature/quality, and can be used on a non-hard surface (e.g. carpet)
• InBody 570 provides segmental information about weight, skeletal muscle mass, body fat mass, intracellular and extracellular water, dry lean mass

Body mass index measures human body shape, based on Pt's mass and height. It is calculated by weight (kg), divided by height squared (m^2).

The classification of BMI is:

• Severely underweight, <16
• Underweight, 16-18.5
• Healthy weight, 18.5-25, or in Asians, 18.5-23
• Overweight, 25-30, or in Asians, 23-27
• Obese, >30, or in Asians >27

Source: NIH

There are age and gender specific BMI charts that should be used, as BMI rises in the 1st year of life, falls during preschool years, then rises again into adolescence. Source: Boys | Girls

Waist circumference is considered at risk when:

• In men, >94cm (>37 inches), or at very high risk at >102cm (>40 inches)
• In women, >80cm (>31.5 inches), or at very high risk at >88cm (>34.5 inches)

Source: Heart Foundation

Waist-to-hip ratio (WHR) is the ratio of the circumference of the waist to that of the hips. Abdominal obesity is defined as WHR>0.9 for men, and >0.8 for women (with 0.7 recommended for women), or BMI>30.

Abdominal circumference (AC) is an U/S measurement of the abdominal circumference at the umbilical region (at level of liver and stomach). It assesses for growth retardation.

Body fat percentage is the the total mass of body fat, divided by total body mass. Body fat includes essential body fats (i.e. necessary to maintain life and reproductive functions) and storage body fat (i.e. fat accumulation in adipose tissue, protecting internal organs in the chest and abdomen). The percentage of essential body fat in women (10%) is greater than that for men (4%), due to demands of childbearing and other hormonal function. Body fat can be measured with calipers or bioelectrical impedance analysis.

In women:

• >10% Essential fat
• >14% Athletes
• >21% Fitness
• >25% Average
• >32% Obese

In men:

• >5% Essential fat
• >6% Athletes
• >14% Fitness
• >18% Average
• >25% Obese

• Failure to thrive
• Height
• Growth
• Low birth weight
• Macrosomia
• Maternal obesity (effects on pregnancy)