Fig. 1.
The comorbidity of primary headaches and poor sleep. The red line part represent the headache suffers, the black line part represent the poor sleep suffers and the grids part represent the comorbidity
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.