Development of an item bank for computerized adaptive test (CAT) measurement of pain.
OBJECTIVE
Patient-reported outcomes should ideally be adapted to the individual patient while maintaining comparability of scores across patients. This is achievable using computerized adaptive testing (CAT). The aim here was to develop an item bank for CAT measurement of the pain domain as measured by the EORTC QLQ-C30 questionnaire.


METHODS
The development process consisted of four steps: (1) literature search, (2) formulation of new items and expert evaluations, (3) pretesting and (4) field-testing and psychometric analyses for the final selection of items.


RESULTS
In step 1, we identified 337 pain items from the literature. Twenty-nine new items fitting the QLQ-C30 item style were formulated in step 2 that were reduced to 26 items by expert evaluations. Based on interviews with 31 patients from Denmark, France and the UK, the list was further reduced to 21 items in step 3. In phase 4, responses were obtained from 1103 cancer patients from five countries. Psychometric evaluations showed that 16 items could be retained in a unidimensional item bank. Evaluations indicated that use of the CAT measure may reduce sample size requirements with 15-25% compared to using the QLQ-C30 pain scale.


CONCLUSIONS
We have established an item bank of 16 items suitable for CAT measurement of pain. While being backward compatible with the QLQ-C30, the new item bank will significantly improve measurement precision of pain. We recommend initiating CAT measurement by screening for pain using the two original QLQ-C30 pain items. The EORTC pain CAT is currently available for "experimental" purposes.
The Research Unit, Department of Palliative Medicine, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, 2400, Copenhagen, NV, Denmark. Morten.Aagaard.Petersen@regionh.dk.
Morten Aa
MA
Petersen
Division of Psychosocial Research and Epidemiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
Neil K
NK
Aaronson
Department of Public Health, Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei City, Taiwan.
Wei-Chu
WC
Chie
Medical Oncology Department, Institut de cancérologie de Lorraine, Vandoeuvre-lès-Nancy, France.
Thierry
T
Conroy
Psychoncology Unit, Sant'Andrea Hospital, Faculty of Medicine and Psychology, Sapienza University, Rome, Italy.
Anna
A
Costantini
Department of Otolaryngology Head and Neck Surgery, Sahlgrenska University Hospital, Göteborg University, Göteborg, Sweden.
Eva
E
Hammerlid
Regional Centre for Excellence in Palliative Care, Department of Oncology, Oslo University Hospital, Oslo, Norway.|European Palliative Care Research Centre, Faculty of Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
Marianne J
MJ
Hjermstad
Palliative Medicine Unit, University Hospital of Trondheim, Trondheim, Norway.
Stein
S
Kaasa
European Palliative Care Research Centre, Faculty of Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.|National Resource Centre for Late Effects After Cancer Treatment, Oslo University Hospital, Oslo, Norway.
Jon H
JH
Loge
Cancer Research UK Centre, University of Leeds, Leeds, UK.
Galina
G
Velikova
Lynda Jackson Macmillan Centre, Mount Vernon Hospital, Middlesex, UK.
Teresa
T
Young
The Research Unit, Department of Palliative Medicine, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, 2400, Copenhagen, NV, Denmark.|Institute of Public Health, University of Copenhagen, Copenhagen, Denmark.
Mogens
M
Groenvold
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003201:Computers; D003718:Denmark; D005260:Female; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000628:therapy; D010146:Pain / Q000523:psychology*; D010147:Pain Measurement / Q000379:methods*; D011594:Psychometrics / Q000379:methods*; D011788:Quality of Life / Q000523:psychology*; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D006113:United Kingdom; D055815:Young Adult
Computerized adaptive test; EORTC QLQ-C30; Item banking; Item response theory; Pain assessment; Patient-reported outcome