Codes and Frequencies
For sample adults age 18+, PANICYR reports responses to the question, "During the past 12 months, did you ever have a spell or an attack when all of a sudden you felt frightened, anxious, or very uneasy?"
As discussed in more detail below, PANICYR was part of a series of mental health questions constituting the NHIS version of the Composite International Diagnostic Interview - Short Form (CIDI-SF) screening scale for panic attack.
According to the Field Representative's Manual for 1999, this set of questions on panic attacks was included "to determine if the Sample Adult has attacks when they suddenly feel frightened, anxious, or very uneasy; whether they occurred in a life-threatening situation; how many attacks in the past year and when was the most recent one; did they happen when the Sample Adult was not in danger or the center of attention; and what other physical reactions occurred when they were having these attacks."
The Composite International Diagnostic Interview - Short Form (CIDI-SF) is a modified version of the World Health Organization's Composite International Diagnostic Interview (CIDI). Two versions of the CIDI-SF were developed, one for the NHIS and one for the World Health Organization (WHO). Both the NHIS version and the WHO version of the CIDI-SF provide brief screening measures for psychiatric illnesses defined by the Diagnostic and Statistical Manual, 4th Edition (DSM-IV).
The 1999 NHIS CIDI-SF includes screening scales for major depression and anxiety (generalized anxiety disorder and panic attack). More information on the major depression questions--for dyphoric mood and for anhedonia, respectively--can be found in DEP2WKEV and DEPLIFUN. For more information on the generalized anxiety disorder questions, see WOR1MO.
In the next section, the elements and skip patterns used in the NHIS version of the CIDI-SF for panic attack are presented, and differences between the NHIS and WHO filter questions are noted. A later section covers scoring the NHIS CIDI-SF for panic attack.
NHIS and WHO CIDI-SF screening and symptom questions
The CIDI-SF instrument for panic attack began with a series of screening questions that determined whether respondents qualified for a second round of questioning on panic attack symptoms. PANICYR (Ever had panic attack, past 12 months) was the first screening question asked. Persons with an affirmative response in PANICYR (IPUMS NHIS code 2) qualified for a second round of screening questions that determined the circumstances under which the respondents' attacks occurred.
The first of these questions about the circumstances of the attacks asked, "Did any of these attacks occur when you were in a life-threatening situation?" (PANICTHREAT).
Persons with an affirmative response in PANICTHREAT were asked, "Did any of these attacks occur when you were not in a life-threatening situation?" (PANICNOTHRET).
Respondents who indicated that their attack(s) occurred in a non-life-threatening situation (A "No" in PANICTHREAT or a "Yes" in PANICNOTHRET) received an additional screening question that asked, "Did [this attack/all of these attacks] happen in a situation when you were not in danger or not the center of attention?" (PANICNODANGR). Persons whose answer to PANICTHREAT was "unknown" and, in the NHIS instrument, those who volunteered that their attack "wasn't in a life-threatening situation" in PANICTHREAT also received PANICNODANGR.
In the NHIS instrument, persons who passed the first three filter questions (PANICYR, PANICTHREAT, PANICNOTHRET) and who answered "Yes" in PANICNODANGR then received a series of questions on panic attack symptoms.
With the NHIS instrument, only persons who had at least one panic attack in the past 12 months that occurred in a non-life-threatening situation and when they were neither in danger nor the center of attention were asked about panic attack symptoms.
The WHO CIDI-SF instrument included additional filter questions about surrounding circumstances that were left out of the NHIS instrument.
These additional filter questions determined whether the attacks occurred in situations that usually caused the respondent unreasonably strong fear, and only respondents who indicated that their attacks did not occur in such situations then received the panic attack symptom questions in the WHO CIDI-SF.
Respondents who passed the sets of filter questions in the WHO and NHIS instruments (namely, PANICYR, PANICTHREAT, PANICNOTHRET, and PANICNODANGR for the NHIS version) were asked about the following panic attack symptoms:
- Heart pounds in panic attacks (PANICHEART)
- Chest/stomach discomfort in panic attacks (PANICCHEST)
- Sweat in panic attacks (PANICSWEAT)
- Tremble in panic attacks (PANICTREMBL)
- Hot flashes or chills in panic attacks (PANICCHILL)
- Surroundings seem unreal in panic attacks (PANICUNREAL)
In both the NHIS and WHO CIDI-SF instruments, persons who passed the first three filters (PANICYR, PANICTHREAT, PANICNOTHRET) were also asked, "About how many attacks did you have in the past 12 months?" (PANICYRNO).
Respondents who received PANICYRNO were also asked, "In what month and year did you have the most recent attack?" Responses to this question were recorded in two variables, PANICWHENMO and PANICWHENYR, that respectively report the month and year of the respondents' most recent attack.
Although the CIDI-SF screening scale for panic attack allows researchers to calculate the likelihood that a respondent meets the diagnostic criteria for this mental disorder (i.e., psychiatric caseness), NHIS documentation does not provide scoring instructions for calculating panic attack scores, nor do the public use files of the NHIS include summary recodes for the CIDI-SF variables.
According to the Appendix on Adult Mental Health Documentation included in the 1999 NHIS Survey Description, "NCHS suggests that individual CIDI-SF items not be used for purposes beyond those recommended by the World Health Organization (WHO)." The Survey Description then directs users to the WHO's website for instructions on how to calculate the probability of psychiatric diagnosis based on responses to individual CIDI-SF items.
As previously noted, respondents must pass all filter questions to receive further questions on panic attack symptoms (with four filter questions included in the NHIS instrument). Respondents who do not pass these filters receive a score of zero (zero probability of psychiatric caseness for panic attack).
According to the scoring system for the CIDI-SF screening scale for panic attack, respondents who pass the filter questions and go on to the panic attack symptom questions receive one point for each of the symptoms they endorse. Summing the number of endorsed symptoms results in a panic attack score ranging from 0 to 6. Respondents with a score of 3 or more are classified as a probable case for panic attack.
Users are cautioned, however, that the WHO CIDI-SF survey instrument uses more stringent criteria in its skip pattern than does the NHIS survey instrument. As mentioned above, according to the scoring guide published by the World Health Organization, only respondents who report that their attacks do not usually occur in situations that cause them unreasonably strong fear receive further symptom questions. The NHIS survey instrument, by contrast, does not include such exclusion criteria. More people will therefore be classified as probable cases for panic attack with the NHIS survey instrument than with the WHO CIDI-SF instrument.
IHIS has created the variable PANICCDC as a summary measure for the panic attack score, based on the scoring system and skip patterns of the NHIS version of the CIDI-SF.
Respondents who failed to pass the full series of filter questions (i.e., persons who did not have at least one panic attack in the past twelve months that occurred in a non-life-threatening situation when they were neither in danger nor the center of attention) receive a score of 0 in PANICCDC. For persons who did pass the series of filter questions, the value of PANICCDC equals the number of physical symptoms of panic attack acknowledged, with a maximum value of 6. PANICCDC thus has a value ranging from 0 to 6, with a score of 3 or more indicating a probable case for panic attack.
- 1999: Sample adults age 18+.
- 1999 : SAMPWEIGHT