3020441 MCID minimal clinically important difference 3861 2485165 MCIDs minimal clinically important differences 286 1249439 MID minimal clinically important difference 18 3045279 MIDs minimal clinically important differences 2 1914184 MCID's minimal clinically important differences 1 1912554 MCID-SE minimal clinically important differences 1 3044553 MICD minimal clinically important differences 1