• 1
    Wright BD. Common sense for measurement. Rasch Meas Trans 1999;13: 7045.
  • 2
    Rasch G. Probabilistic Models for Some Intelligence and Attainment Tests. Chicago: University of Chicago Press, 1960 (Reprinted 1980).
  • 3
    Streiner D, Norman G. Health Measurement Scales. Oxford: Oxford University Press, 1989.
  • 4
    McKenna SP, Whalley D, Cook S. Improving the sensitivity of the Quality of Life in Depression Scale (QLDS). Qual Life Res 2002;11: 625.
  • 5
    Ellis B. Basic Concepts in Measurement. Cambridge: Cambridge University Press, 1966.
  • 6
    Svensson E. Guidleines to statistical evaluation of data from rating scales and questionnaires. J Rehabil Med 2001;33: 478.
  • 7
    Kaziz L, Anderson JJ, Meenan RF. Effect sizes for interpreting changes in health status. Med Care 1989;27: S178S189.
  • 8
    Andrich D. Rasch Models for Measurement. Series: Quantitative Applications in the Social Sciences No. 68. London: Sage Publications, 1988.
  • 9
    Embretson SE, Reise SP. Item Response Theory for Psychologists. NJ: Lawrence Erlbaum, 2000.
  • 10
    Luce RD, Tukey JW. Simultaneous conjoint measurement: a new type of fundamental measurement. J Math Psychol 1964;1: 127.
  • 11
    Rasch G. On general laws and the meaning of measurement in psychology. In: NeymanJ, ed., Proceedings of the Fourth Berkeley Symposium on Mathematical Statistics and Probability, IV. Berkeley CA: University of California Press, 1961.
  • 12
    Wright BD, Masters GN. Rating Scale Analysis. Chicago: MESA Press, 1982.
  • 13
    Van Alphen A, Halfens R, Hasman A, Imbos T. Likert or Rasch? Nothing is more applicable than a good theory. J Adv Nurs 1994;20: 196201.
  • 14
    Smith RM. Fit analysis in latent trait measurement models. J Appl Meas 2000;2: 199218.
  • 15
    Holland PW, Wainer H, eds. Differential Item Functioning. Mahwah, NJ: Lawrence Erlbaum Associates, 1993.
  • 16
    Smith RM. Applications of Rasch Measurement. Sacramento: JAM Press, 1992.
  • 17
    Cella DF, Lloyd SR, Wright BD. Cross-cultural instrument equating: current research and future directions. In: SpilkerB, ed., Quality of Life and Pharmacoeconomics in Clinical Trials 2nd ed. Philadelphia: Lippincott-Raven Publishers, 1996.
  • 18
    Bond TG, Fox CM. Applying the Rasch Model: Fundamental Measurement for the Human Sciences. Mahwah, NJ: Lawrence Erlbaum Associates, Inc., 2001.
  • 19
    Smith EV Jr. Evidence for the reliability of measures and validity of measure interpretation: a Rasch measurement perspective. J Appl Meas 2001;2: 281311.
  • 20
    Birnbaum A. Some latent trait models and their use in inferring an examinee's ability. In: LordFM, NovickMR, eds., Statistical Theories of Mental Test Scores. Reading, MA: Addison-Wesley, 1968.
  • 21
    Van der Linden WJ, Hambleton RK, eds. Handbook of Modern Item Response Theory. New York: Springer, 1997.
  • 22
    Perline R, Wright BD, Wainer H. The Rasch model as additive conjoint measurement. Appl Psychol Meas 1979;3: 23756.
  • 23
    Silverstein B, Kilore KM, Fisher WP, et al. Applying psychometric criteria to functional assessment in medical rehabilitation: I. Exploring unidimensionality. Arch Phys Med Rehabil 1991;72: 6317.
  • 24
    Haley SM, McHorney CA, Ware JE Jr. Evaluation of the MOS SF-36 Physical Functioning Scale (PF-10): I. Unidimensionality and reproducibility of the Rasch item scale. J Clin Epidemiol 1994;47: 67184.
  • 25
    Shulman JA, Wolfe EW. Development of a nutrition self-efficacy scale for prospective physicians. J Appl Meas 2000;1: 10730.
  • 26
    Doward LC, McKenna SP, Kohlmann T, et al. The international development of the RGHQoL: a quality of life measure for recurrent genital herpes. Qual Life Res 1998;7: 14353.
  • 27
    McKenna SP, Whalley D, Renck-Hooper U, et al. The development of a quality of life instrument for use with post-menopausal women with urogenital atrophy in the UK and Sweden. Qual Life Res 1999;8: 3938.
  • 28
    McKenna SP, Doward LC, Alonso J, et al. The QoL-AGHDA: an instrument for the assessment of quality of life in adults with growth hormone deficiency. Qual Life Res 1999;8: 37383.
  • 29
    Whalley D, McKenna SP, Dewar AL, et al. A new instrument for assessing quality of life in atopic dermatitis: International Development of the Quality of Life Index for Atopic Dermatitis (QoLIAD). Br J Dermatol 2004;150: 27483.
  • 30
    Whalley D, McKenna SP, Dewar AL, et al. Quality of life in adults with atopic dermatitis—the international development of the QoLIAD. Qual Life Res 2000;9: 322.
  • 31
    McKenna SP, Cook SA, Whalley D, et al. Development of the PSORIQoL, a psoriasis-specific measure of quality of life designed for use in clinical practice and trials. Br J Dermatol 2003;149: 32331.
  • 32
    Whalley D, McKenna SP, Dewar AL, et al. International development of a measure to assess quality of life in childhood atopic dermatitis—the PIQOL-AD. Qual Life Res 2000;9: 302.
  • 33
    Dobby J, Duckworth D. Objective Assessment by Means of Item Banking. Schools Council Examination Bulletin 40. London: Evans/Methuen Educational, 1979.
  • 34
    Revicki DA, Cella DF. Health status assessment for the twenty-first century: item response theory, item banking and computer adaptive testing. Qual Life Res 1997;6: 595600.
  • 35
    Wainer H. Computerized Adaptive Testing (2nd ed.). Mahwah, NJ: Lawrence Erlbaum Associates, 2000.
  • 36
    McKenna SP, Doward LC, Whalley D, et al. The development of the PsAQoL: a quality of life instrument specific to Psoriatic Arthritis. Ann Rheum Dis 2004;63: 1629.
  • 37
    Doward LC, Whalley D, Dewar AL, et al. The development of the SLE-QoL: a quality of life instrument specific to Systemic Lupus Erythematosus. Qual Life Res 1999;8: 609.
  • 38
    Doward LC, Spoorenberg A, Cook SA, et al. The development of the ASQoL: a quality of life instrument specific to Ankylosing Spondylitis. Ann Rheum Dis 2003;62: 206.
  • 39
    Cook SA, Whalley D. Looking for common ground: a first step towards comparing quality of life across diseases. Proc Br Psychol Soc 2001;9: 64.
  • 40
    Wirén L, Whalley D, McKenna SP, Wilhelmsen L. Application of a disease-specific, quality-of-life measure (QoL-AGHDA) in growth hormone-deficient adults and a random population sample in Sweden: validation of the measure by Rasch analysis. Clin Endocrinol (Oxf) 2000;52: 1435.
  • 41
    Rapp SR, Feldman SR, Exum ML, et al. Psoriasis causes as much disability as other major medical diseases. J Am Acad Dermatol 1999;41: 4017.
  • 42
    Nichol MB, Margolis JE, Lippa E, et al. The application of multiple quality of life instruments in individuals with mild-to-moderate psoriasis. Pharmacoeconomics 1996;10: 64453.
  • 43
    Merbitz C, Morris J, Grip JC. Ordinal scales and foundations of misinference. Arch Phys Med Rehabil 1989;70: 30812.
  • 44
    Wright BJ, Linacre JM. Observations are always ordinal; measurements, however, must be interval. Arch Phys Med Rehabil 1989;70: 85760.
  • 45
    Streiner DL, Norman GR. Health Measurement Scales: a Practical Guide to Their Development and Use2nd ed. Oxford: Oxford University Press, 1995.