In a panel study of u5s, I regularly used HAZ when I allowed children to remain in the panel until 7 yo. I was interested in testing the catch-up hypothesis. And there was almost zero catch-up after age 5y according to the HAZ results.

Technically correct? I have never seen an evaluation of the technical validity of using HAZ in an older population. In theory, because low H/A persists over a lifetime, you will be picking up a population that is congenitally short. But is this stunting...or a consequence of childhood stunting?

So I think the answer resides in interpretation. But HAZ tells us nothing about the current nutritional status of an entire all-age population.

Hi Nicholus,

I observed that this became a common concern among frontline nutrition actors in countries, no wonder in this era of rapid advances in research and review for evidences. I tried to answer your queries below.

Yes, stunting together with other nutritional retardations are not reversable after two years of age, but it does not mean growth and nutritional needs stopped at that period; 

For Q1. Yes, we can still use HAZ for stunting in that > 5 yrs old population. Why? Here are some extracts from analyses.

Even if stunting in early childhood is not reversible, further damage to nutritional status and cognitive function needs to be prevented. For children ages five to nine years, malnutrition increases the risk of underweight, anemia, and illness; these conditions decrease attendance, performance, and years in primary school

In HICs, 15 percent of adult height is attained in adolescence. By ages 15–19 years, girls attain their adult height, although their pelvis continues to grow. If girls are undernourished during pelvic development, they have the increase risk of - poor birth outcomes - prematurity, stillbirths, and neonatal deaths and of dying. (https://www.ncbi.nlm.nih.gov/books/NBK525239/

For Q3; Yes, it is technically correct. Stunting (HAZ) indicator is a useful marker of current broader society- or population-level conditions and a predictor (though not a cause of) long-term health and development outcomes (USAID 2020). https://www.advancingnutrition.org/resources/stunting-considerations-use-indicator-nutrition-projects

Stunting indicator is useful to prioritize the most vulnerable population or subpopulation groups for nutrition intervention programs and also for comparing the same populations over time.

An example of the use of HAZ for nutrition programs for older children and adolescents (and women of reproductive age) - you may use the stunting indicator for prioritizing and/or beneficiary targeting of population sub-groups to maximize inclusion of most people vulnerable for poor birth outcomes, prematurity, stillbirths and neonatal deaths and also at high risk of overweight and NCD (20% -30% of adolescents live with chronic illnesses, particularly diabetes - Save the Children 2015).

However, since malnutrition is attributed by the outcomes from multiple sectors, in prioritization exercise for Myanmar Multisectoral National Plan of Action for Nutrition (MS-NPAN-2018-2023), we have used stunting together with other nutrition specific and nutrition sensitive indicators.    

For Q2;

Yes, using HAZ alone for measuring projects’ success which usually are of short time frame-5 years- is not appropriate.

USAID noted that stunting is a higher-level indicator of the cumulative, longer-term impacts of a variety of environmental factors. To measure project success, a broader set of lower-level indicators (output, outcome, and intermediate outcome) should also be considered along with the contributions of interventions in other sectors.

Hope that's useful.

Dear Aye, 

Many thanks for this elaborate explanation .  It is of tremedous use.

Thanks, Bill. 

Do you have any articles or textbooks related to the point you mentioned in the second part of your reply?

(In theory, because low H/A persists over a lifetime, you will be picking up a population that is congenitally short.)

I want to use this as a reference in other works. 

Thanks for your very informative reply, Sayar Aye Thwin. 

Those help a lot to me to understand how HAZ is used in nutrition programming. After digesting all of this, I still left one question - can we interpret the HAZ score as stunting in those older age groups? Because some programs want to use it in that way in the over 5 years old age group and want to interpret it as stunting prevalence at this age. For me, that is not technically uncomfortable to make interpretations in that way.