Description

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

Defining Spastic Colon Records and Identifying Persons with Spastic Colon

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

For 1975 and 1978-1981, spastic colon records were defined as those condition records with a code of "5641" ("Irritable colon") in the variable DCICDCOD in the original NHIS public use files. This condition code value comes from the International Classification of Diseases (ICD) codes. Additionally, to be considered "chronic," spastic colon 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 spastic colon records were defined as those condition records with a code of "312" ("Spastic colon") 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.

Weights
For 1975, SPASCYRC should be weighted with PERWEIGHT.

For 1978 to 1981, SPASCYRC should be weighted with CONDWT1.

For 1982 to 1996, SPASCYRC should be weighted with CONDWT3.

Comparability

As with all of the person-level condition variables created by IHIS from condition records prior to 1997, the universe for SPASCYRC 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 spastic colon in the past year. There is also a minor universe change between the sets of years 1978-1981 and 1982-1996. These changes require 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

• 1975, 1978-1996

Weights

• 1975 : PERWEIGHT
• 1978-1981 : CONDWT1
• 1982-1996 : CONDWT3