TY - CONF T1 - An investigation into the validity of the EQ-5D-5L, SF-12, ASCOT and WEMWBS in older people using item response theory and differential item functioning JO - QUALITY OF LIFE RESEARCH PY - 2018/10/01 AU - Penton H AU - Young T AU - Dayson C AU - Hulme C ED - VL - 27 SP - S62 EP - S62 Y2 - 2024/12/22 ER -