To find out if a recently implemented intervention reduced the problem of malnutrition among five year-old children in a given village, a researcher may ask: “Which summary statistic is most appropriate?”

Change in mean or median daily calorie intake of all five year-olds in village?

Change in the proportion of five year-old children in village falling below the predetermined minimum calorie requirement?

he criteria for making such choices include:

• Face validity (i.e. is the statistic relevant to the specific concern?).
• Whether stakeholders understand how the data was derived.
• Whether stakeholders are able to interpret the findings as intended.