Potential harm thresholds for allowing parents to choose less effective treatment
| Severity of harm | Example harms | Example case | Acceptable probability of risk eventuating |
| Serious | Death Long-term disability | Refusing a vitamin K injection for a newborn could lead to clotting and has an increased risk of death30 | Small <5% |
| Medium | Painful procedure Additional surgery Short-term illness | Refusing a complete surgical repair of a broken leg (because it requires a blood transfusion) and instead opting for an incomplete repair, increasing the need for additional surgeries and the risk of surgical complications51 | Medium <15% |
| Small | Somewhat painful procedure Slightly increased length of illness | Refusing antibiotics for an ear infection may lengthen the duration of the illness52 | Large <50% |
| Trivial | Very short-lasting pain | Ear piercing causes mild pain that quickly resolves53 | Certain 100% |