Ninety one per cent (2884/3183) of women aged 40-74 years reported ever having had a cervical smear, and 93% (1778/1919) aged 53-74 years reported ever having had a mammogram (table 1). We found similarly high rates in all age groups for each screening type, except for women aged 65-69 and 70-74 years among whom a much lower percentage reported ever having had a cervical smear (84% (330/391) and 81% (314/390)). One in 40 (52/1919) women aged 53-74 years reported never having had either breast or cervical screening, and 84% (1600/1919) reported having had both screening types. Only 1% (12/940) of women aged 55-64 reported never having had a mammogram or a cervical smear.
Table 1 Screening history by age group of respondent, Great Britain 2005-7
Cars available to the household (P=0.01) and housing tenure (P=0.002) were both significant predictors of ever having had a mammogram, after adjustment for age and sociodemographic factors (table 2). Women in households with one car had an odds of ever having had a mammogram 1.67 (95% confidence interval 1.06 to 2.62) times that of women in households with no cars, and those in households with two or more cars had an odds 2.65 (1.34 to 5.26) times that of women in households with no cars, after adjustment for all the other factors. Women who owned their home with a mortgage had an odds ratio of ever having had a mammogram of 2.12 (1.12 to 4.00), and those who owned their home outright an odds ratio of 2.19 (1.39 to 3.43), compared with women in rented housing. We found no significant associations between ever having had a mammogram and highest level of education, National Statistics socioeconomic classification, ethnicity, or region.
Table 2 Odds ratios of screening history (ever mammogram, ever cervical smear) by sociodemographic characteristics, Great Britain 2005-7*
Only ethnicity was a significant predictor of ever having had a cervical smear after adjustment for age and sociodemographic factors (P=0.0005). White British women had an odds of ever having had a cervical smear 2.20 (1.41 to 3.42) times that of women of other ethnicity. Women with a degree had an odds of ever having had a cervical smear 1.78 (1.01 to 3.13) times, and those with qualifications less than a degree had an odds 1.48 (1.03 to 2.14) times, that of women with no qualifications after adjustment for age and sociodemographic variables. Women in intermediate occupations had an odds ratio of ever having had a cervical smear of 1.51 (1.03 to 2.20) compared with women in routine and manual occupations.
Although these results indicate that the significant predictors are different for breast and cervical screening, we then combined the two types of screening to enable us to investigate women who were good overall screeners (table 3). Cars (P=0.006), housing tenure (P=0.04), and education (P=0.04) were significant predictors of having had both breast and cervical screening compared with having had only one or neither screening type, after adjustment for age and sociodemographic factors. Ethnicity was the only statistically significant predictor when we compared women who had had some screening with those who had had none (P=0.02). White British women had a fully adjusted odds ratio of having had some screening versus none of 3.01 (1.22 to 7.38) compared with women of other ethnicity. However, very few women overall had never had either screen (52 women aged 53-74), so these figures are based on very small numbers.
Table 3 Odds ratios of screening history (ever both screenings, ever some screening) by sociodemographic characteristics, Great Britain 2005-7*
Among the 1778 women aged 53-74 who had ever had a mammogram, 1553 (87.7%, 95% confidence interval 85.9% to 89.3%) had had their most recent mammogram as routine screening by the NHS Breast Screening Programme (table 4); a further 80 (4.3%, 3.4% to 5.4%) were non-routine referrals to the NHS, and 57 (3.5%, 2.6% to 4.6%) were follow-ups after treatment for breast cancer. Although almost as high a percentage of women aged 70-74 had ever had a mammogram as had women in younger age groups (table 1), routine screening unsurprisingly accounted for a lower proportion of most recent mammograms in this age group whereas non-routine NHS referrals accounted for a higher proportion. These differences, however, were not significant.
Table 4 Reason for most recent mammogram (among women who had ever had a mammogram), Great Britain 2005-7. Values are percentage (number) (95% confidence interval) unless stated otherwise
Just under two thirds (1172/1919) of women aged 53-74 had had a mammogram in the previous three years, decreasing from 80% (154/198) of those aged 53-54 to 58% (223/391) in the 65-69 age group and 27% (108/390) in the 70-74 age group (fig 1). Eighty nine per cent (600/688) of women in their 50s had had a mammogram in the previous six years, as had 80% (678/841) of those in their 60s and 48% (187/390) of the 70-74 age group. Of women who had not had a hysterectomy, around three quarters of those in each age group from 40-44 and 55-59 years had had a cervical smear in the previous five years and a further approximately 5% had one more than five years previously (fig 2). Unsurprisingly, among women aged 60 and over, the percentage who had a smear less than five years previously decreased with age; the percentage who had one longer ago increased with age, as did the percentage reporting never having had one. Most women knew when they had last had a mammogram, in contrast with the higher proportion of women who did not know the date of their most recent cervical smear.
Fig 1Time since most recent mammogram, all women aged 53-74
Fig 2Time since most recent cervical smear, women aged 40-74 who had not had a hysterectomy