Codes and Frequencies
ADDEV identifies those sample children age 2 to 17 (and, in 2007, sample adults age 18+) whom a doctor or health professional had diagnosed as having "Attention Deficit Disorder [ADD]" [for 1997-99] or "Attention Deficit Hyperactivity Disorder [ADHD] or Attention Deficit Disorder [ADD]" [for 2000 forward].
The Field Representative's Manual includes definitions of these neurobehavioral disorders, but this information was not routinely shared with respondents. The Manual for 1997 states that ADD "is diagnosed by a mental health professional and is characterized by developmentally inappropriate inattention, impulsiveness, and varying hyperactivity." The Manual for 1998-1999 reports that ADD "is diagnosed by an education or health professional and is characterized by developmentally inappropriate inattention and impulsiveness." The Manual for 2000 and subsequent years states that Attention Deficit Disorder or Attention Deficit Hyperactivity Disorder "is diagnosed by a health professional and is characterized by problems with attention, impulsiveness, hyperactivity, school problems, and sometimes aggression."
The criteria for diagnosing ADHD/ADD are codified in the American Psychiatric Association's Diagnostic and Statistical Manual.
Initially, the DSM used the term "Attention Deficit Disorder [ADD]" to label this neurobehavioral disorder. Later, the DSM recognized 3 types of "Attention Deficit Hyperactivity Disorder [ADHD]," marked by inattention, hyperactivity/impulsiveness, or both. The change in survey question wording [with both ADD and ADHD mentioned beginning in 2000] largely mirrors a shift in medical terminology rather than a substantive change or broadening of the concept being measured in the variable ADDEV. A 1999 diagnosis of a given individual by a health professional would probably specify ADD; a 2002 diagnosis of the same individual would probably specify ADHD of a specific type. Because the NHIS question was retrospective ["has a doctor or health professional ever told you"], both diagnostic labels were included beginning in 2000, without substantially compromising comparability over time.
The Field Representative's Manual for 2001 forward explicitly treats ADD and ADHD as equivalent, with the words, "Attention Deficit Hyperactivity Disorder [also called Attention Deficit Disorder, ADD or ADHD]."
The NHIS questionnaire was substantially redesigned in 2019 to introduce a different data collection structure and new content. For more information on changes in terminology, universes, and data collection methods beginning in 2019, please see the user note.
- 1997-2006: Sample children age 2 to 17.
- 2007: Sample adults age 18+ and sample children age 2 to 17.
- 2008-2018: Sample children age 2 to 17.
- 2019-2021: Sample children age 2 to 17.
- 1997-2021 : SAMPWEIGHT