title: Defining minimally important change in QOLIE-31 scores: estimates from three placebo-controlled lacosamide trials in patients with partial-onset seizures.
abstract: The Quality of Life Inventory in Epilepsy (QOLIE-31) is a valuable tool to assess the impact of antiepileptic drugs on patients' lives, but interpretation of mean score changes can be challenging. Minimally important change (MIC) thresholds can be used to describe the proportion of clinically improved or worsened patients. Pooled data from Phase II/III trials of adjunctive lacosamide in patients with treatment-resistant partial-onset seizures were used to estimate MIC thresholds for the QOLIE-31 total score and subscales. Using multiple distribution- and anchor-based estimation methods, the optimal MIC value for the total score in this population of patients with treatment-resistant seizures was 5 points, which is lower than those previously reported in the literature for mixed populations. MIC estimates varied substantially across QOLIE-31 subscales. Taken together, these results demonstrate that intrinsic characteristics of a patient population impact what should be considered as MIC, a key consideration in the clinical interpretation of QOLIE-31 change scores.
authors.affiliation: UCB Pharma, Allée de la Recherche, 60, 1070 Brussels, Belgium. Simon.Borghs@ucb.com
authors.forename: Simon
authors.initials: S
authors.lastname: Borghs
authors.forename: Christine
authors.initials: C
authors.lastname: de la Loge
authors.forename: Joyce A
authors.initials: JA
authors.lastname: Cramer
mesh_terms: D000081:Acetamides / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000627:therapeutic use*; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D004828:Epilepsies, Partial / Q000188:drug therapy* / Q000523:psychology*; D006801:Humans; D000078334:Lacosamide; D008875:Middle Aged; D015233:Models, Statistical; D015337:Multicenter Studies as Topic; D011581:Psychological Tests; D011788:Quality of Life; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000081:Acetamides; D000927:Anticonvulsants; D000078334:Lacosamide