CRAWLAGEWK is a 3-digit-numeric variable.
0: Not in Universe
996: Never crawled
998: Unknown whether crawled
999: Unknown when crawled
For sample persons under 5 years old, CRAWLAGEWK reports the age (in weeks) at which the child first crawled when left lying on his or her stomach.
For related variables, please use the IPUMS NHIS search function and drop-down menus.
- 1981: Sample persons under 5 years old.
- 1981 : SAMPWEIGHT