title: Is there a response shift in generic health-related quality of life 6 months after glioma surgery?
abstract: Patients may recalibrate internal standards when faced with a serious diagnosis or neurological deficits. This so-called response shift is important to understand in longitudinal health-related quality of life (HRQoL) data, but this is not quantitatively assessed in glioma patients.
  
  
  
  Patients with gliomas were eligible for this HRQoL study. We used EuroQol-5D 3 L to assess generic HRQoL with assessment preoperatively and at 6 months postoperatively. At time of follow-up, patients scored how they considered their baseline HRQoL in retrospect using the same questionnaire ("then-test").
  
  
  
  Seventy-three patients were enrolled between January 2013 and September 2015. With the then-test approach, the mean EQ-5D 3 L index was similar compared to baseline (0.77, mean difference 0.01, 95% CI -0.57 to 0.07, p = 0.82). Also, then-test and baseline VAS score were similar (mean difference 0, 95% CI -7 to 7, p = 0.97). However, a 0.10-0.13 difference from baseline was observed in patients that improved or deteriorated in HRQoL at follow-up according to the then-test EQ-5D 3 L index value. The direction of change as observed from the then-test was similar to the direction of clinical change, reducing the impact of any HRQoL change from baseline to follow-up.
  
  
  
  On average, we observed no response shift using EQ-5D 3 L in the selection of glioma patients able to participate at 6 months after surgery. However, following change in HRQoL at follow-up, response shift seems to reduce the effects of HRQoL changes by lowering of internal standards in patients that deteriorate and raising the standards in patients that improve.
authors.affiliation: Department of Neurosurgery, Sahlgrenska University Hospital, Blå Stråket 5, vån 3, 413 45, Göteborg, Sweden. legepost@gmail.com.|Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. legepost@gmail.com.|Department of Neurosurgery, St. Olavs Hospital, Trondheim, Norway. legepost@gmail.com.
authors.forename: Asgeir Store
authors.initials: AS
authors.lastname: Jakola
authors.affiliation: Department of Neurosurgery, St. Olavs Hospital, Trondheim, Norway.|Norwegian Advisory Unit for Ultrasound and Image-Guided Therapy, St. Olavs University Hospital, Trondheim, Norway.|Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Ole
authors.initials: O
authors.lastname: Solheim
authors.affiliation: Department of Neurosurgery, St. Olavs Hospital, Trondheim, Norway.|Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.|Norwegian Centre of Competence in Deep Brain Stimulation for Movement Disorders, St. Olavs University Hospital, Trondheim, Norway.
authors.forename: Sasha
authors.initials: S
authors.lastname: Gulati
authors.affiliation: Department of Neurosurgery, St. Olavs Hospital, Trondheim, Norway.|Norwegian Advisory Unit for Ultrasound and Image-Guided Therapy, St. Olavs University Hospital, Trondheim, Norway.|Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Lisa Millgård
authors.initials: LM
authors.lastname: Sagberg
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000601:surgery*; D005260:Female; D005910:Glioma / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000523:psychology; D011184:Postoperative Period; D011788:Quality of Life; D011795:Surveys and Questionnaires / Q000592:standards
keywords: Brain neoplasm; Glioma; Neurosurgery; Quality of life; Surgical management