Party Member health bar showing as low

Seems to be similar to bug RRBUG-I-95

Whilst in a party, in multiplayer, when looking at a party member their health bar is showing that they are low on health, eg. 25 out of 100, but the player in question has a full bar of health on their end and hasn't taken any damage. This doesn't last long, and tends to fix itself, but still confusing for both players. It doesn't seem to actually affect the players health, it's just showing as low as they walk past their party member.