How are Dwelling Units, Families, Reporting Units, and Persons Related to One Another in MEPS Data?
MEPS uses a complex survey design to collect information on members of the civilian, non-institutionalized population. In the course of data collection, several analytic and data collection units are defined: Dwelling Units selected from primary sampling units contain families that are then divided into Reportung Units. Individuals within these Reporting Units provide information, but not all individuals respond to the interview and survey questions. What do all these terms mean? And how are they related to one another? Below, we define these terms and describe the relationships between Dwelling Units, Reporting Units, Families, and Persons.
Please note, this user note assumes readers are familiar with the sequential overlapping panel design of the MEPS. If you are not yet familiar with this, please read the user note on the MEPS panel design before reading this user note.
Part 1: Defining Key Concepts and Terms
Dwelling Unit (DU)
Definition: The Dwelling Unit is the physical structure that is part of a primary sampling unit (PSU) for NHIS sampling purposes.
The MEPS definition of a DU is generally consistent with the National Health Interview Survey definition. For example, the 2018 NHIS Survey Description document describes households as "occupied housing units" (p. 10) that exclude "long-term care institutions (for example, nursing homes for the elderly, hospitals for the chronically ill or physically or intellectually disabled, and wards for abused or neglected children), correctional facilities (for example, prisons or jails, juvenile detention centers, and halfway houses)" (p. 8). Additionally, "unless one other family member is a civilian eligible for the survey (for example, a child whose parents are both active-duty military)" (p. 8), housing units occupied by active-duty Armed Forces personnel are also excluded from the survey.
Please see the 2018 NHIS Survey Description for more information on the NHIS sample design.
Variables containing DU information in IPUMS MEPS
Please note, for the purposes of pooling or linking data across time, DUID is unique within a panel, but must be combined with PANEL to be uniquely identified across panels.Back to Top
Reporting Unit (RU)
Definition: A Reporting Unit (RU) is comprised of a person or group of persons in the sampled DU who are related by blood, marriage, adoption, or other family association. Each RU is interviewed as a single entity and is used as a unit when administering the survey, rather than an analytic unit.
All members of an RU are assigned the same RU letter identifier, and students living away from home are treated as their own RU.
Variables containing RU information in IPUMS MEPS
There are two items of note. First, an RU is unique within a DU but to uniquely identify an RU within a PANEL, RULETR must be combined with DUID. To uniquely identify an RU across panels, RULETR must be combined with DUID and PANEL. Second, to analyze families, useres should use the definitions of family explained in the next section.Back to Top
Definition: Families in MEPS are comprised of a person or group of persons in the sampled DU who are related by blood, marriage, adoption, or other family association. There are two kinds of families in MEPS.
Key facts about families in MEPS
- There are TWO types of families that are identified in MEPS
- MEPS-defined families: A MEPS defined family consists of one or more persons related to one another by blood, marriage, adoption or who otherwise self-identified as a single family unit. This includes cohabiting partners and, until 2017, foster children.
- CPS-defined families, in contrast exclude non-married partners and in-laws.
- Families differ from RUs only in that, when defining families, student RUs are combined with their parents' RU, resulting in one family unit that may contain people belonging to one or more different RUs.
I want to use MEPS to study families. When should I use CPS-defined families? When should I use MEPS-defined families?
The CPS definition of a family is used to assign poverty classifications to families according to existing federal standards (POVCAT, POVLEV, POVCATCPS). If you are interested in replicating family-level estimates from other sources, use CPS families. On the other hand, if you are interested in studying outcomes related to individuals who identify as a family unit, use the MEPS family (FAMIDYR).
Variables used to identify families in IPUMS MEPS:
- FAMIDYR: Annual family identifier (MEPS family definition)
- FAMIDRD: Family identifier (MEPS family definition), round record
- CPSFAMID: Annual family identifier (CPS family definition)
Please note, for the purposes of pooling or linking data across time, a family is unique within a DU and to uniquely identify a family within a panel, the family identificationv ariabl must be combined with DUID. To uniquely identify a family across panels, the family identification variable must be combined with both DUID and PANEL.Back to Top
Definition: For the purposes of MEPS, each member of a DU is a person, and a person number, or PID, is assigned to each member of a DU and uniquely identifies individuals within the DU. There are different types of persons, however, in a DU.
In each RU, there is one individual identified as the "respondent" for the RU. This person interacts with the interviewer to answer the MEPS-HC questions for all members of the RU. Additional questionnaires, such as the Diabetes Care Survey and the Self-Administered Questionnaire, are completed by the RU member to whom it applies (for example, the Diabetes Care Survey is completed by the RU member(s) identified as having diabetes in the MEPS-HC by the RU respondent).
Variables used to identify persons and types of persons in IPUMS MEPS:
- PID: Person number
- PIDRD: Person number, round record
- MEPSID: MEPSID (DUID + PID + PANEL)
- MEPSIDRD: MEPSID (DUIDRD + PIDRD + PANELRD), round record
- RESP: First respondent indicator as of December 31
- REFPRS: Reference person as of December 31
Please note, for the purposes of pooling or linking data across time, a person number is unique within a DUID. PID must be combined with DUID to uniquely identify a person within a panel. The IPUMS MEPS generated variable MEPSID combines DUID, PID, and PANEL to uniquely identify an individual across panels.Back to Top
Part 2: An Example of Key Concepts in Practice
Figure 1. DUID 12615 from the 2017 data (HC-201)