Which formula is used to measure BMI?

Appeared in: MP CHO -2019 (Shift-2)

Explanation

The universally accepted formula for Body Mass Index (BMI) is calculated by dividing a person's weight in kilograms by the square of their height in meters.
This formula is also referred to as the Quetelet's Index.
It provides a standardized measure to assess if a person's weight is healthy in proportion to their height.
The units must be correct (kilograms for weight and meters for height) for the calculation to be accurate.

Option A: This formula is incorrect because it uses height in centimeters (cm) instead of meters (m). The standard BMI calculation requires height to be in meters.
Option C: This formula is incorrect because it uses height in feet, which is an imperial unit, with weight in kilograms, a metric unit. The standard formula uses metric units for both weight and height.
Option D: This option is incorrect because a correct formula is provided in the options.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Calculation of Body Mass Index (BMI) as background academic context rather than a clinical decision trigger.
BMI is a fundamental screening tool in nursing and healthcare to quickly identify individuals who may be underweight, overweight, or obese.
A high BMI is associated with an increased risk for several chronic conditions, including type 2 diabetes, hypertension, cardiovascular disease, and certain cancers. A low BMI can indicate malnutrition.
It is important for nurses to remember that BMI is a screening tool, not a diagnostic tool. It does not distinguish between fat mass and muscle mass. Therefore, a comprehensive nutritional assessment should also include factors like waist circumference, body composition, and overall health status.

How to Approach the Question

First, read the question carefully to understand that it's asking for the specific formula for BMI.
Recall the standard definition and formula for Body Mass Index.
Examine each option, paying close attention to the units of measurement (kg vs. lbs, meters vs. cm vs. feet) and the mathematical operations (e.g., squaring the height).
The standard formula uses metric units: weight in kilograms (kg) and height in meters (m).
Identify the option that matches the correct formula: Weight (kg) / [Height (m)]².
Eliminate the other options based on incorrect units or mathematical operations.

Concept Tested & Keywords

QbbN1p_ZMJ8lP8Dj1GxBlu

E6 Nursing Fundamentals Potter Perry 12e Part 5 p. 190-192

E6 Nutrition Kumud Khanna 2e p. 212-214

E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 468-470

Practise the full MP CHO -2019 (Shift-2)

Attempt every question from this paper in a timed mock, then review the full solution for each one.