Table 1

Characteristics of cohort participants with 0, 1 and multiple episodes of IID during their follow-up time, UK 2008-9
Number of episodes
None Single Multiple
Variable No. % No % No % χ2 p
Age group
  <1 year 24 57.1% 9 21.4% 9 21.4% 180.20 <0.001
  1 to 4 years 182 62.5% 86 29.6% 23 7.9%
  5 to 14 years 517 82.9% 90 14.4% 17 2.7%
  15 to 64 years 3,357 84.5% 518 13.0% 99 2.5%
  65+ years 1,666 87.5% 198 10.4% 41 2.2%
Sex
  Male 2,307 86.2% 300 11.2% 69 2.6% 15.92 <0.001
  Female 3,439 82.7% 601 14.4% 120 2.9%
NS-SEC1
  Managerial and professional occupations 2,938 82.6% 514 14.5% 105 3.0% 30.32 0.001
  Intermediate occupations 256 83.1% 47 15.3% 5 1.6%
  Small employers and own account workers 574 82.7% 96 13.8% 24 3.5%
  Lower supervisory and technical occupations 620 89.5% 63 9.1% 10 1.4%
  Semi-routine and routine occupations 408 86.4% 53 11.2% 11 2.3%
  Not classifiable 950 85.4% 128 11.5% 34 3.1%
Quintile of deprivation2
  1 (most deprived) 420 87.1% 49 10.2% 13 2.7% 12.48 0.131
  2 644 86.2% 80 10.7% 23 3.1%
  3 1,515 83.3% 247 13.6% 56 3.1%
  4 1,798 83.9% 286 13.4% 58 2.7%
  5 (least deprived) 1,366 83.1% 239 14.5% 39 2.4%
Urban/rural indicator2
  Urban 3,445 84.5% 514 12.6% 116 2.8% 15.06 0.005
  Town 766 86.3% 96 10.8% 26 2.9%
  Rural 1,532 81.9% 291 15.6% 47 2.5%

1 National-Statistics Socioeconomic Classification; 2 3 missing values.

Tam et al.

Tam et al. BMC Public Health 2013 13:739   doi:10.1186/1471-2458-13-739

Open Data