... each SF-36 item to identify independent predictors and classify them according to Little and Rubin ("missingcompletely at random”, “missing at random” and “missing not at random”). Results: ... missing quality of life dataa problem in clinical trials of cancer therapy?. Statistics in Medicine 1998,17:66 7-6 77.3. Fayers PM, Curran D, Machin D: Incomplete quality of life data in randomized ... miss-ing items varied between 2% and 7%. The type of miss-ingness was missing at random for 18 items (items PF1,RP1, RP3, BP2, GH1, GH4, RE 2 and all items of VT, SF and MH subscales) and...