Description

NASPOLYPYRC indicates whether the person had a chronic nasal polyp 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 NASPOLYPYRC) created from the pre-1997 condition records, see the User Note on Condition Records and Condition Variables.

Defining Nasal Polyp Records and Identifying Persons with a Nasal Polyp

For all available years, persons who were asked a direct question about having a nasal polyp and who have a chronic nasal polyp condition record are given a "Yes" code for NASPOLYPYRC. Persons who were asked a direct question about a nasal polyp but do not have a chronic nasal polyp record are given a code of "No." Persons who were not asked a direct question about a nasal polyp, 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 nasal polyp record.

For 1970 and 1978, nasal polyp records were defined as those condition records with a code of "505" ("Nasal polyp") in the variable DCICDCOD in the original NHIS public use files. This condition code value comes from the International Classification of Diseases (ICD), Revision 8. Additionally, to be considered "chronic," nasal polyp condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.

For 1979 to 1981, nasal polyp records were defined as those condition records with a code of "4710" through "4719" ("Nasal polyps") in the variable DCICDCOD in the original NHIS public use files. These condition code values come from ICD Revision 9. As with earlier years, to be considered "chronic," nasal polyp condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.

For 1982 to 1996, chronic nasal polyp records were defined as those condition records with a code of "604" ("Nasal polyps") in the variable C1CONDRC in the original NHIS public use files. This condition code value comes from NCHS's Diagnostic Recode C: Chronic Conditions and Impairments.

Comparability

As with all of the person-level condition variables created by IHIS from condition records prior to 1997, the universe for NASPOLYPYRC 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 a nasal polyp in the past year. This change requires that different weight variables be used depending on which years of data are analyzed. See the "Weights" 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, 1978-1996

Weights

• 1970 : PERWEIGHT
• 1978-1996 : CONDWT6