1. An Item Response Theory-Based Pain Item Bank Can Enhance Measurement Precision 
Jin-shei Lai, PhD, Kelly Dineen, PhD, Bryce B. Reeve, PhD, Jamie Von Roenn, MD, Daniel Shervin, MD, Michael McGuire, MD, Rita K. Bode, PhD, Judith Paice, PhD, RN, David Cella, PhD 
Journal of Pain and Symptom Management 
Volume 30, Issue 3, Pages (September 2005)
DOI: /j.jpainsymman
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

2. Fig. 1
Comparison of item statistics results between general cancer patients and prostate cancer patients.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

3. Fig. 2 Item characteristics of 43 core items.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

4. Fig. 3
Bank precision level among the pain continuum.aRasch scaled score has been converted to a 0–100 interval scale with 0 being severe pain and 100 being minimal/no pain. bLocations of each response category for item ‘I have pain’ on the pain continuum: 1) ‘very much’: smaller than (scaled score = −1.73), 2) ‘quite a bit’ between and (scaled scores of −1.73 and −0.21), 3) ‘somewhat’: between and 50.0 (scaled score of −0.21 and 0.93), 4) ‘a little bit’: between and (scaled score of 0.93 and 3.46), and 5) ‘not at all’: greater than (scaled score = 3.46). cPain scores were significantly different across groups classified by response categories of the item ‘I have pain’, F (4, 288) = , P< Post hoc testing (Tukey HSD) showed that every group was different from others except the comparison between ‘very much’ and ‘quite a bit’, and between ‘very much’ and ‘somewhat.’
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

5. Fig. 4
Comparison of precision between item bank, short form, and one single 0–10 rating scale item along the continuum. aNo patient endorsed 10 (worst pain) and therefore, this figure only compared precision levels from 0-9 to scores from the item bank and the short-form. bLocations of each rating of the single item on the pain continuum were based on the logarithm transformation. Results showed that these ratings did not equally distribute on the continuum.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions