Figure 2.

Intervals between measurements of blood phenylalanine concentrations in PKU individuals with PAH c.1222C>T variants

The durations of intervals between Phe-monitoring checks are plotted by age. Recommended guidelines for how often Phe should be checked varies with age and is indicated in gray. Most individuals did not check Phe concentrations frequently enough, as evidenced by the fact that most monitoring intervals fell outside the recommended range.