Question

Severe acute malnutrition as per WHO criteria is defined as:

• A. Weight for age less than median plus -2 SD
• B. Weight for height less than median plus 2 SD
• C. Weight for age less than median plus 3 SD
• D. Weight for height less than median minus -3 SD

Hint:

SAM is graded by wasting (weight-for-height), with the severe cut-off below -3 SD.

Answer 1

The Correct Option is D

Step 1: Recall the WHO classification grid. Acute malnutrition (wasting) is assessed by the weight-for-height/length index, while chronic malnutrition (stunting) uses height-for-age and underweight uses weight-for-age.
Step 2: Moderate acute malnutrition sits between $-2$ SD and $-3$ SD of weight-for-height. The severe form lies below the $-3$ SD threshold.
Step 3: So severe acute malnutrition corresponds to a weight-for-height Z-score below $-3$, equivalent to visible severe wasting or MUAC below 115 mm or nutritional oedema.
Step 4: Choices built on weight-for-age (a, c) describe underweight, and the $+2$ SD choice (b) describes overweight, so they are excluded. The weight-for-height $-3$ SD option is the only one that fits the SAM definition.
\[\boxed{\text{Weight for height less than median minus -3 SD}}\]