Table 4

Frequency of self-reported adverse events expressed as event rate (%) for each group, absolute risk increase, relative risk and number needed to harm*

Adverse event (months)Customised foot orthosesSham foot orthosesAbsolute risk of harm increase (95% CI)Relative risk of harm (95% CI)Number needed to harm (95% CI)
0–127/54 (50.0)23/55 (41.8)0.08 (−0.10 to 0.26)1.20 (0.79 to 1.80)12 (−10 to 4)
1–311/49 (22.4)11/50 (22.0)0.00 (−0.16 to 0.17)1.02 (0.49 to 2.13)223 (−6 to 6)
3–69/47 (19.1)3/48 (6.3)0.13 (−0.01 to 0.27)3.06 (0.88 to 10.62)8 (−121 to 4)
6–124/45 (8.8)5/45 (11.1)−0.02 (−0.16 to 0.11)0.80 (0.23 to 2.79)−45 (−6 to 9)
  • *Some participants reported more than one adverse event.