§ A simple or 'pragmatic' analysis of the SMR02 flat file was conducted under the direction of ISD staff. This was compared with a more extensive ('comprehensive') trawling of that file, which includes multiple entries for maternal smoking on a few women admitted to maternity units for antenatal care (e.g. due to premature labour or preeclampsia). We concluded that the pragmatic approach provided an adequate estimate of information available.
Difference between records obtained using pragmatic and comprehensive approach accounted for by:
•Duplicate records: 94 women with duplicate records counted only once in Comprehensive approach.
•Missing admission year: 175 records with missing admission year were excluded from Comprehensive approach.
It is clear that SMR02 does not capture all women who give birth with information at maternity booking. Total births in Scotland for year ending 31st March 2005 was 52721 - Information Services Division and 53849 - General Register Office.