Sample children were classified as having a disability based on the reported responses to the following variables:

• VDIFAMOUNT reports the amount of trouble with vision

• HRPROBAMT reports the amount of trouble with hearing

• WALKDIF1BL1 reports the amount of difficulty walking one block without equipment

• WALKDIF5BL1 reports the amount of difficulty walking five blocks without equipment

• WALKDIF1BL2 reports the amount of difficulty walking one block using equipment or assistance

• WALKDIF5BL2 reports the amount of difficulty walking five blocks using equipment or assistance

• SELFCAREDIF reports the amount of difficulty with self care, such as eating or dressing

• UNDRSTIHH reports the amount of difficulty being understood by people inside the household

• UNDRSTOHH reports the amount of difficulty being understood by people outside the household

• LEARNDIF reports the amount of difficulty learning things

• LAMEMCONDIF reports the amount of difficulty remembering things

• CONCDIF reports the amount of difficulty concentrating on activities

• ACPTCHGDIF reports the amount of difficulty accepting changes to routine

• BEHAVEDIF reports the amount of difficulty controlling behavior

• MKFRNDIF reports the amount of difficulty making friends

• DEPFREQ reports how often feel depressed

• WORFREQ reports how often feel worried, nervous, or anxious

In 2019, functioning and disability measures included on the NHIS questionnaire were modified to align with validated, internationally-comparable disability measures developed by the Washington Group on Disability Statistics (WG). For more information about the WG initiative, other WG functioning and disability measures included on the NHIS questionnaire, and guidance for researchers about how to use the WG measures in analyses, please see our user note on the Washington Group Disability Measures.