BMC Public Health 2008, 8:126 http://www.biomedcentral.com/1471-2458/8/126 FMiagpusrheo3wing Postcode Sector G15 6 by DECPAT and SIMD Data Zones Map showing Postcode Sector G15 6 by DECPAT and SIMD Data Zones. SIMD = Scottish Index for Multiple Depri- vation. and MD = 56.9%) compared to females (LD = 24.3% and MD = 46%). There was an age difference for both males and females (non-response rate higher for 35–44 com- pared to 55–64 year olds) in both MD and LD subjects. Discussion The study was successful in recruiting subjects of the desired sex and age profile from the most and least deprived areas of Glasgow. Data zones in SIMD were the preferred choice for our sampling process because each covers a smaller area and population (750–1,000) than the Postcode sectors which were used in a previous, well used deprivation classification (DEPCAT)[63]. This is illustrated in Figure 3 which shows the Postcode sector G15 6 (DEPCAT 6) and the same area by data zones (SIMD quintiles 1–5). The G15 6 area has nine data zone areas which have clear boundaries between the various quintiles in the SIMD and consists of least and most deprived areas. The Information Services Division (ISD) Scotland has recommended that routine and in-depth NHS Board level analyses from 1997 onwards use SIMD measure of deprivation[64]. In recruiting for the present study we found similar pat- terns of response to those observed in earlier surveys. In the Scottish Health Survey of 2003 (SHS 2003) from the co-operating households, response was lowest among those aged 16–24. Among men, response was highest among those aged 65 plus, while among women those aged over 24 gave a consistently high response rate[65]. In SHS 2003, men aged below 35 years were slightly under- represented at both interview and nurse visit relative to their proportions in the population while men aged 55 and over were slightly over-represented. Women aged below 25 years were under-represented at both stages, while women aged 45–74 were overrepresented[65]. The availability of the GPASS information allowed us to examine at least some potential bias inherent in our recruitment strategy. Of particular concern was the possi- Page 8 of 11 (page number not for citation purposes)