Table 1 Summary of the definitions of time to quality of life score deterioration approach retained for the simulation study

MCID 5-point

Reference score

Deterioration

TTD ≥ 5-points

Baseline

Not definitive

TUDD ≥ 5-points with no further improvement 5 points as compared to reference score

Baseline

Definitive

TTD ≥ 5-points

Best previous score

Not definitive

TUDD ≥ 5-points with no further improvement 5 points as compared to reference score and

Best previous score

Definitive