Codes and Frequencies
EMPSTATIMP4 is a variable that includes imputed values to replace missing data for the original variable EMPSTAT (employment status). While the original EMPSTAT variable provides considerable detail about an individual's labor force status (distinguishing, for example, between those who were working for pay, those who were working without pay, and those who were temporarily absent from a job or business), EMPSTATIMP4 is a simple dichotomous variable distinguishing between adults who were "employed" (IPUMS NHIS code 1) and adults who were "not employed" (IPUMS NHIS code 2). The complementary imputation flag variable IMPEMPSFLAG4 indicates whether values in EMPSTATIMP4 were reported or imputed.
In the EMPSTATIMP variables, dichotomous employment status for 1997-2000 was decided by reported employment status last week, reported work-for-pay status in the past year, or, in the case of missing values, imputation. For 2001 forward, dichotomous employment status was decided by reported work-for-pay status in the past year or imputation.
Related Variables on Income Imputation
EMPSTATIMP4 is the fourth of five variables that contain imputed values for employment status. It was created as part of a set of variables that provide complete (i.e., without missing values) data on family income.
One of the purposes of NHIS data is to study relationships between income and health and to monitor health and health care for persons at different income levels. However, non-response rates are high for questions on total family income and personal earnings from employment in the previous calendar year. To obtain estimates of these variables for all survey participants, the National Center for Health Statistics created variables with values imputed for missing data for 1997 forward, using multiple-imputation methodology. The NHIS public use files with multiply imputed data consist of five files (and thus five versions of variables containing imputed values for missing data), one for each set of imputed values, to allow the assessment of variability due to imputation. For more information on the imputation methodology, see EMPSTATIMP1.
Before using the imputed income and earnings variables, researchers are strongly advised to read the NCHS documentation on imputed income, such as 2018 Imputed Family/Personal Earnings Files and "Multiple Imputation of Family Income and Personal Earnings in the National Health Interview Survey: Methods and Examples".
- 1997-2018: Persons age 18+.
- 1997-2018 : PERWEIGHT