Table 7

Relative risks of mortality from acute myeloid leukaemia and chronic myeloid leukaemia by levels of estimated cumulative magnetic field exposure in subcohort with work histories (n = 79 972) (four separate analyses): study of United Kingdom electricity generation and transmission workers, 1973–97

Cumulative magnetic field exposure (μT.y)7-150 n RR7-151 (95% CI) RR7-152 (95% CI)
Acute myeloid leukaemia7-153:
 0–2.4251.01.0
 2.5–4.971.49(0.64 to 3.48)1.51(0.64 to 3.62)
 5.0–9.981.06(0.47 to 2.40)1.02(0.43 to 2.43)
 10.0–19.960.92(0.37 to 2.30)0.84(0.32 to 2.20)
 ⩾20.031.20(0.36 to 4.04)1.16(0.33 to 4.02)
 p Value for trend7-154 p>0.50 and >0.50p>0.50 and >0.50
Chronic myeloid leukaemia7-160:
 0–2.491.01.0
 2.5–4.942.12(0.65 to 6.93)1.60(0.47 to 5.38)
 5.0–9.941.27(0.38 to 4.21)0.97(0.28 to 3.38)
 10.0–19.920.72(0.15 to 3.42)0.63(0.13 to 3.16)
 ⩾20.010.96(0.12 to 7.72)0.81(0.10 to 6.76)
 p Value for trend7-154 p>0.50 and >0.50p>0.50 and >0.50
  • 7-150 See footnote 7-151table 6.

  • 7-151 Analysed simultaneously with sex and attained age.

  • 7-152 Analysed simultaneously with sex, age, calendar period, year of starting employment, and negotiating body. For levels, see table 4.

  • 7-153 Any part of death certificate coded to ICD-9 205.0.

  • 7-154 See footnote ††table 6.

  • 7-160 Any part of death certificate coded to ICD-9 205.1.