Table 1.

Attributes and levels included in the discrete choice experiment

Attributes	Levels
Pain outcomes:
1. Day-time pain 9–12 months after surgery	No day-time pain, moderate day-time pain, severe day-time pain
2. Night-time pain 9–12 months after surgery	No night-time pain, moderate night-time pain, severe night-time pain
Functional outcomes:
3. Standing and walking on a flat surface 9–12 months after surgery	No difficulty standing and walking;
	Moderate difficulty standing and walking, severe difficulty standing and walking
4. Bending to floor, rising from sitting, going up and down stairs 9–12 months after surgery	No difficulty bending to floor, rising from sitting, going up and down stairs
	Moderate difficulty bending to floor, rising from sitting, going up and down stairs
	Severe difficulty bending to floor, rising from sitting, going up and down stairs
Risk of complications:
5. Risk of having to go back into hospital and have a second operation on your knee	0 %, 7 %, 13 %
6. Risk of getting a complication that requires seeing GP or specialist for further treatment	0 %, 10 %, 21 %