Description

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

Defining Sciatica Records and Identifying Persons with Sciatica

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

For 1973 and 1978, sciatica records were defined as those condition records with a code of "353" ("Sciatica") in the variable CDICDCOD 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," sciatica condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.

For 1979-1996, sciatica records were defined as those condition records with a code of "7243" ("Sciatica") in the variable CDICDCOD in the original NHIS public use files. This condition code value comes from ICD Revision 9. As with earlier years, to be considered "chronic," sciatica condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.

Comparability

As with all of the person-level condition variables created by IHIS from condition records prior to 1997, the universe for SCIATICAYRC 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 sciatica in the past year. There are also minor universe differences among the sets of years 1978-1981, 1982-1983, and 1984-1996. These changes require 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

• 1973, 1978-1996

Weights

• 1973 : PERWEIGHT
• 1984-1996 : CONDWT1
• 1978-1981 : CONDWT3
• 1983 : CONDWT4
• 1982 : CONDWT5