Cost effectiveness estimates by age group (five year outcomes and costs in NZ$ for 2000)
| Age 5–12 | Age 13–18 | Adults | |
|---|---|---|---|
| Number of helmets required | 10195 | 84999 | 328162 |
| Cost of helmets (a) ($) | 180792 | 1507312 | 5819397 |
| Head injuries averted | |||
| Short stay hospital inpatient | 16.9 | 43.4 | 114.4 |
| Long stay hospital inpatient | 1.2 | 3.3 | 13.8 |
| Total head injuries averted | 18.1 | 46.8 | 128.2 |
| Total healthcare costs averted ($) | 28387 | 75110 | 173158 |
| Total societal costs averted (b) ($) | 471920 | 1279050 | 4289602 |
| Cost per head injury averted ($) | 9990 | 32241 | 45396 |
| Benefit:cost ratio (b/a) | 2.610 | 0.849 | 0.737 |
| Net benefit (societal perspective; b–a) ($) | 291128 | −228262 | −1529796 |