FIGURE 2.
Mean digit span test scores for groups of high and low MCH, MCV, and ferritin. Error bars represent SEM.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.