Table 1.

Cohort characteristics

Characteristic20052006200720082009
Number of practices444451455461467
Region, n (%)
  North West66 (14.9)67 (14.9)67 (14.7)67 (14.5)68 (14.6)
  London57 (12.8)59 (13.1)60 (13.2)61 (13.2)63 (13.5)
  South West42 (9.5)43 (9.5)43 (9.5)43 (9.3)43 (9.2)
  West Midlands41 (9.2)41 (9.1)43 (9.5)43 (9.3)44 (9.4)
  South Central41 (9.2)41 (9.1)41 (9.0)43 (9.3)43 (9.2)
  South East Coast41 (9.2)41 (9.1)41 (9.0)41 (8.9)41 (8.8)
  Scotland36 (8.1)39 (8.6)40 (8.8)40 (8.7)42 (9.0)
  East of England34 (7.7)34 (7.5)34 (7.5)35 (7.6)35 (7.5)
  Wales30 (6.8)30 (6.7)30 (6.6)31 (6.7)31 (6.6)
  Northern Ireland17 (3.8)17 (3.8)17 (3.7)17 (3.7)17 (3.6)
  Yorkshire and Humber16 (3.6)16 (3.5)16 (3.5)16 (3.5)16 (3.4)
  East Midlands15 (3.4)15 (3.3)15 (3.3)15 (3.3)15 (3.2)
  North East8 (1.8)8 (1.8)8 (1.8)9 (2.0)9 (1.9)
Deprivation quintile, n (%)
  0 (least deprived)82 (18.5)82 (18.2)83 (18.2)84 (18.2)84 (18.0)
  187 (19.6)91 (20.2)91 (20.0)92 (20.0)94 (20.1)
  292 (20.7)94 (20.8)95 (20.9)95 (20.6)96 (20.6)
  387 (19.6)87 (19.3)89 (19.6)91 (19.7)91 (19.5)
  4 (most deprived)96 (21.6)97 (21.5)97 (21.3)99 (21.5)102 (21.8)
Number of patients38 57941 64844 69647 86050 679
Mean age (SD), years35.8 (22.5)35.8 (22.5)35.8 (22.5)35.9 (22.6)35.9 (22.6)
Males, n (%)18 994 (49.2)20 612 (49.5)22 167 (49.6)23 767 (49.7)25 135 (49.6)
Number of tests99 569116 466133 309149 446161 838
  • Percentages do not add to 100 due to rounding.