Calibration of an Item Pool for Assessing the Burden of Headaches: An Application of Item Response Theory to the Headache Impact Test (HIT™)
Background: Measurement of headache impact is important in clinical trials, case detection, and the clinical monitoring of patients. Computerized adaptive testing (CAT) of headache impact has potential advantages over traditional fixed-length tests in terms of precision, relevance, real-time quality...
Veröffentlicht in: | Quality of Life Research. - Springer Science + Business Media. - 12(2003), 8, Seite 913-933 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2003
|
Zugriff auf das übergeordnete Werk: | Quality of Life Research |
Schlagworte: | Computerized adaptive testing Disability Headache Health status Impact Item response theory Migraine Quality of life Questionnaires Severity mehr... |
Zusammenfassung: | Background: Measurement of headache impact is important in clinical trials, case detection, and the clinical monitoring of patients. Computerized adaptive testing (CAT) of headache impact has potential advantages over traditional fixed-length tests in terms of precision, relevance, real-time quality control and flexibility. Objective: To develop an item pool that can be used for a computerized adaptive test of headache impact. Methods: We analyzed responses to four well-known tests of headache impact from a population-based sample of recent headache sufferers (n = 1016). We used confirmatory factor analysis for categorical data and analyses based on item response theory (IRT). Results: In factor analyses, we found very high correlations between the factors hypothesized by the original test constructers, both within and between the original questionnaires. These results suggest that a single score of headache impact is sufficient. We established a pool of 47 items which fitted the generalized partial credit IRT model. By simulating a computerized adaptive health test we showed that an adaptive test of only five items had a very high concordance with the score based on all items and that different worst-case item selection scenarios did not lead to bias. Conclusion: We have established a headache impact item pool that can be used in CAT of headache impact. |
---|---|
ISSN: | 15732649 |