Definition
HIDX reports the young child's line number in the woman respondent's health history section. For children who are included in the health history (normally, children under age 3, 4, or 5), the value of HIDX is the same as the child's line number in the birth history (BIDX).
After asking, "Now I would like to record the names of all your births, whether still alive or not, with the first one you had," the interviewer recorded each child's name in turn on successively numbered lines printed in the "Reproduction" section of the individual woman's questionnaire.