National Vital Statistics System

Matched Multiple Birth Data Set

NCHS has a Matched Multiple Birth Data Set that contains six years of detailed data for matched sets of twins, triplets, and quadruplets for data years 1995 to 2000 on cd-rom.

The matched multiple birth data set includes six combined years of data and sets of quadruplets. “The Matched Multiple Birth File” was developed to allow for analysis of characteristics of sets of births and fetal deaths in multiple deliveries. Such analysis is not possible using the traditional NCHS Live Birth and Fetal Death Files because these files contain individual records of births and deaths in multiple deliveries, but do not identify set members. Thus characteristics specific to the multiple set (e.g., gender combination of the set, outcome of the set, birthweight differences among set mates) are not available. Over 98 percent of records were matched. Included on the file are 325,516 sets of twins; 12,157 sets of triplets; and 760 sets of quadruplets. The dataset allows researchers to investigate such topics as the viability of multiples by gender of the set and birthweight discordancy among set mates.

For more information on this cd-rom, contact:

Reproductive Statistics Branch
National Center for Health Statistics
3311 Toledo Road, Room 7318
Hyattsville, Maryland 20782

Telephone: (301) 458-4362 or (301) 458-4111