In Wave 5, this was a non-experimental study that tested the feasibility of asking respondents whether they are a twin (e_twin), the person number of their co-resident twin (e_twinpno), whether they would disclose their twin’s address (e_getwin) and the likelihood that twin would participate in a follow-up study (e_twinresp).
Variables are in the “Twin Module” in record e_indresp_ip.
