Table 3 Estimated impact of WannaCry on total activity during the WannaCry week

From: A retrospective impact analysis of the WannaCry cyberattack on the NHS

  At actually infected trust If all trusts were infected
Activity difference Costed difference Activity difference Costed difference
Total admissions −2935.6 −£4.0 m −17,562.1 −£24 m
[−5067.2, −803.9] [−£6.6 m, −£1.5 m] [−30,314.8, −4809.3] [−£39.3 m, −£8.8 m
Emergency admissions −1066 −£2.1 m −6386.6 −£12.6 m
[−1558.5, −573.5] [−£3.1 m, −£1.1 m] [−9337.1, −3436.1] [−£18.4 m, −£6.8 m]
Elective admissions −2175.6 −£1.9 m −13,162.2 −£11.5 m
[−3815.9, −535.3] [−£3.5 m, −£0.3 m] [−23,086.1, −3238.3] [−£20.9 m, −£2.0 m]
Day case admissions −1857.7 −£1.2 m −11,016.4 −£7.2 m
[−3038.6, −676.7] [−£2.0 m, −£0.4 m] [−18,019.6, −4013.1] [−£11.8 m, −£2.6 m]
Elective admissions excl. day cases −315.8 −£0.7 m −1907.7 −£4.2 m
[−676.6, 45.1] [−£1.5 m, £0.1 m] [−4087.9, 272.4] [−£9.1 m, £0.6 m]
A&E attendances −3760.2 −£0.6 m −20,648.6 −£3.3 m
[−4781.7, −2738.7] [−£0.8 m, −£0.4 m] [−26,224.6, −15,072.6] [−£4.1 m, −£2.4 m]
Outpatient appointments 3328.8 £0.2 m 9303.7 £0.9. m
[−21,730.7, 28,388.3] [−£2.3 m, £2.6 m] [−140,860.5, 159,467.9] [−£13.7 m, £15.5 m]
Outpatient attendances −12,166.8 −£1.2 m −71,860.0 −£7.0 m
[−31,562.4, 7228.8] [−£3.1 m, £0.7 m] [−186,415.1, 42,695.2] [−£18.2 m, £4.2 m
Outpatient cancellations 13,534.4 £1.3 m 78,962 £7.7 m
[9453.3, 17,615.4] [£0.9 m, £1.7 m] [54,791.4, 103,132.6] [£5.3 m, £10.1 m]
Total financial impact   −£5.9 m   −£35.0 m
  [−£8.2 m, −£3.6 m]   [−£48.8 m, −£21.2 m]
  1. Impact of WannaCry on activity calculated as the difference-in-differences estimate for difference in activity multiplied by the number of infected trusts. 95% confidence intervals in square brackets
  2. A&E accident and emergency, m million