What is the concept of growth velocity?

• A. A snapshot of a child's height at a single time point
• B. The total height attained by age 2
• C. The rate of change in height or weight over time
• D. Bone age measurement

Answer: (C)

Growth velocity is the rate at which a child’s height or weight changes over time. This concept matters because it shows how quickly a child is growing, not just how tall or heavy they are at a single moment. Velocity is typically expressed as cm per year for height or kg per year for weight and is calculated by taking the difference between two measurements and dividing by the time elapsed. For example, growing 5 cm over six months corresponds to about 10 cm per year. Monitoring growth velocity helps clinicians detect abnormalities early and assess responses to nutrition or treatment, since normal velocity varies with age and sex. A single height snapshot at one time point confirms current size, but does not indicate how fast growth is occurring; total height by a specific age is an accumulated outcome, not the rate; and bone age measures skeletal maturity rather than growth rate.