Description

BRONCASISYRC indicates whether the person had chronic bronchiectasis in the past year. This variable is created with supplemental programming by the IPUMS NHIS staff from the pre-1997 condition records. For general information about IHIS variables (such as BRONCASISYRC) created from the pre-1997 condition records, see the User Note on Condition Records and Condition Variables.

Defining Bronchiectasis Records and Identifying Persons with Bronchiectasis

For all available years, persons who were asked a direct question about having bronchiectasis and who have a chronic bronchiectasis condition record are given a "Yes" code for BRONCASISYRC. Persons who were asked a direct question about having bronchiectasis but do not have a chronic bronchiectasis record are given a code of "No." Persons who were not asked a direct question about bronchiectasis, or for whom it is unknown whether they were asked such a question, are given a code of "NIU" (not in universe), regardless of whether they have a chronic bronchiectasis record.

For 1970 and 1978, chronic bronchiectasis records were defined as those condition records with a code of "5180" ("Bronchiectasis") in the variable DCICDCOD in the original NHIS public use files. This condition code value comes from the International Classification of Diseases (ICD) codes, Revision 8. Additionally, to be considered "chronic," bronchiectasis condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.

For 1979 to 1983, chronic bronchiectasis records were defined as those condition records with a code of "4940" ("Bronchiectasis") in the variable DCICDCOD in the original NHIS public use files. This condition code value comes from the International Classification of Diseases (ICD) codes, Revision 9. As with earlier years, to be considered "chronic," bronchiectasis condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.

Weights
For 1970, BRONCASISYRC should be weighted with PERWEIGHT.

For 1978 to 1983, BRONCASISYRC should be weighted with CONDWT6.

Comparability

As with all of the person-level condition variables created by IHIS from condition records prior to 1997, the universe for BRONCASISYRC is substantially different for 1978 forward than it is for years prior to 1978. Beginning in 1978, only persons living in 1/6 of households, rather than all persons, were asked a direct question about having bronchiectasis in the past year. This change requires that different weight variables be used depending on which years of data are analyzed. See the "Description" tab for details.

Additionally, there is a change in the way "Yes" responses are coded over time. See the User Note on Condition Records and Condition Variables for details about the composite coding scheme employed by IHIS.

Universe

Availability

• 1970, 1978-1983

Weights

• 1970 : PERWEIGHT
• 1978-1983 : CONDWT6