2.4. Statistical analyses
REGRESSION, REMISSION
These analyses were conducted using the SELECTION induction and maintenance full analysis sets.Patient demographics and baseline characteristics were analysed using descriptive statistics. Changes from induction baseline to week 10 and from maintenance baseline to week 58 were calculated for each HRQoL measure using least-squares [LS] mean changes with 95% confidence intervals [CIs]. Differences in LS mean changes were estimated using analysis of covariance adjusted for baseline HRQoL measures and stratification factors. Treatment assignments and analyses were stratified in Induction Study A by day 1 use of oral systemic corticosteroids and use of immunosuppressants [6-mercaptopurine, azathioprine and methotrexate]; in Induction Study B, by the same factors as in Induction Study A, and by previous exposure to one vs more than one biologic; and in the Maintenance Study, by the same factors as in Induction Study A, and by participation in Induction Study A or B. Binary assessment of the proportion of patients achieving the MCID in each of the HRQoL measures at weeks 10 and 58 was performed using Cochran–Mantel–Haenszel tests. No adjustment for multiple comparisons was made. A logistic regression model was used to calculate odds ratios with 95% CIs for restoration of SF-36-defined HRQoL at week 10 and maintenance of normal SF-36-defined HRQoL at week 58 for filgotinib 200 mg compared with placebo. The proportions of patients who achieved CDC at weeks 10 and 58, and the proportions of patients who had minimal clinically important improvements and declines in HRQoL measures from induction baseline to week 10 and from maintenance baseline to week 58, respectively, among CDC achievers and non-achievers, were compared using Pearson’s chi-squared test.All missing data were imputed using a last observation carried forward approach, except for the proportions of patients in IBDQ remission, for which non-responder imputation was used. Because these were exploratory and 