ID Variables

NOTE: Data from Rounds I-IV cannot be merged with Rounds V-XIII data since entirely different samples were used for RLMS Phase I (Rounds I-IV) and Phase II (Rounds V-XIII). The attempt to merge data sets from Phase I with those from Phase II will generate erroneous results.

In each of the RLMS data sets, the unit of analysis is either a household, a household member, or a survey site, depending upon whether you are looking at household-, individual-, or community-level data. Please note that Person 1 is not necessarily the head of the household.

Rounds I-IV

In Rounds I-IV, the variables SITE and FAMILY identify a unique household and SITE, FAMILY, and PERSON identify a unique individual. SITE is a geographic descriptor; there are up to 360 families within each SITE. The numbers for FAMILY are repeated from site to site and the numbers for PERSON are repeated from family to family. To prevent errors in merging data, use SITE as a primary sort key and FAMILY as a secondary sort key for household-level data and SITE, FAMILY, and PERSON as sort keys for individual-level data.

In Rounds I-IV, as in all subsequent rounds, a code of "1" for gender indicates that the respondent is male, while a code of "2" indicates a female respondent. For birth years, a code of "00" means that the respondent was born in 1900. A code of "99" means that 1899 was the respondent's year of birth.

Round V

In Round V, the variables SITE5 and FAMILY5 identify a unique household and SITE5, FAMILY5, and PERSON5 identify a unique individual. As in Round I, SITE5 is a geographic descriptor and the numbers for FAMILY5 and PERSON5 are repeated within their respective broader categories.

Rounds VI and after

Starting in Round VI, an additional variable is required for unique identification of a household or person. The variables SITE, CENSUSD, and FAMILY identify a unique household and SITE, CENSUSD, FAMILY, and PERSON identify an individual. As in Round I, SITE is a geographic descriptor and the numbers for CENSUSD, FAMILY, and PERSON are repeated within their respective broader categories.

Starting with Round V, each round has a unique individual or family identifier. In both files, this identifier has the same name. For Round V it is AID, for Round VI it is BID, etc. To merge Round V with a later round, use the merge variable AID (at either the household- or individual-level) from the data sets; to merge Round VI with a later round, use BID; etc.

Starting with Round XVI, the variable IDIND has been added to the individual-level data files that allows you to merge people across rounds. This variable needs to be merged with earlier rounds as described above using AID, BID, etc. This variable is included in a file of Household and Individual Longitudinal Identifiers that is available on the Data Downloads page.

Do NOT try to merge rounds using any other combination of variables. To do so will generate erroneous results.