Occupational therapists routinely use rating scales to indicate a client's level of functioning, monitor progress, and evaluate intervention success. Rating scales yield ordinal data, whereas true measurement requires interval level data. Rasch analysis can convert rating scale data into true interval measures, but the use of measures derived from this method is limited in everyday occupational therapy practice because raw data must be computer scored. The keyform is an alternative to computer scoring. It is a paper-and-pencil form with which the therapist can record and convert ratings to interval measures while exercising intuitive quality control of the data. This article illustrates the application of this methodology to the Occupational Performance History Interview-2nd Version (OPHI-II). The authors discuss the OPHI-II scales, describe the methodology for developing the keyforms, and demonstrate how they are used.
BravemanB.HelfrichC. (2001). Occupational identity: Exploring the narratives of three men living with AIDS. Journal of Occupational Science, 8, 25–31.
2.
BridleM. J.LynchK. B.QuesenberryC. M. (1990). Long term function following the central cord syndrome. Paraplegia, 28, 178–185.
3.
FisherA. G. (1999). Assessment of motor and process skills, 3rd ed.Ft. Collins, CO: Three Star Press.
4.
FosseyE. (1996). Using the Occupational Performance History Interview (OPHI): Therapists' reflections. British Journal of Occupational Therapy, 59, 223–228.
5.
HaleyS. M.McHorneyC. A.WareJ. E.Jr. (1994). Evaluation of the MOS SF-36 physical functioning scale (PF-10): I. Unidimensionality and reproducibility of the Rasch item scale. Journal of Clinical Epidemiology, 47, 671–684.
6.
HenryA.TohenM.CosterW.Tickle-DegnenL. (1994, July). Predicting psychosocial functioning and symptomatic recovery of adolescents and young adults following a first psychotic episode.Paper presented at the Joint Annual Conference of the American Occupational Therapy Association and the Canadian Association of Occupational Therapists, Boston, MA.
7.
KielhofnerG.BravemanB.FinlaysonM.Paul-WardA.GoldbaumL.GoldsteinK. (2004). Outcomes of a vocational program for persons with AIDS. American Journal of Occupational Therapy, 58, 64–72.
8.
KielhofnerG.HenryA. (1988). Development and investigation of the Occupational Performance History Interview. American Journal of Occupational Therapy, 42, 489–498.
9.
KielhofnerG.HenryA.WalensD. (1989). The Occupational Performance History Interview. Rockville, MD: American Occupational Therapy Association.
10.
KielhofnerG.HenryA.WalensD.RogersS. (1991). A generalizability study of the Occupational Performance History Interview. The Occupational Therapy Journal of Research, 11, 292–306.
11.
KielhofnerG.MallinsonT. (1995). Gathering narrative data through interviews: Empirical observations and suggested guidelines. Scandinavian Journal of Occupational Therapy, 2, 63–68.
12.
KielhofnerG.MallinsonT.CrawfordC.NowakM.RigbyM.HenryA.. (1997). A user's guide to the Occupational Performance History Interview-II. Chicago: University of Illinois, Model of Human Occupation Clearinghouse. (Translated into Danish, Dutch, Finnish, German, Mandarin, Portuguese, Spanish, and Swedish.)
13.
KielhofnerG.MallinsonT.ForsythK.LaiJ. S. (2001). Psychometric properties of the second version of the Occupational Performance History Interview. American Journal of Occupational Therapy, 55, 260–267.
LynchK.BridleM. (1993). Construct validity of the Occupational Performance History Interview. The Occupational Therapy Journal of Research, 13, 231–240.
18.
MallinsonT.MahaffeyL.KielhofnerG. (1998). The Occupational Performance History Interview: Evidence for three underlying constructs of occupational adaptation (Revised). Canadian Journal of Occupational Therapy, 65, 219–228.
19.
McHorneyC. A.HaleyS. M.WareJ. E.Jr. (1997). Evaluation of the MOS SF-36 Physical functioning scale (PF_10): II. Comparison of relative precision using Likert and Rasch scoring methods. Journal of Clinical Epidemiology, 50, 451–461.
20.
MerbitzC.MorrisJ.GripJ. (1989). Ordinal scales and foundations of misinference. Archives of Physical Medicine and Rehabilitation, 70, 308–332.
21.
NeistadtM. E. (1995). Methods of assessing client's priorities: A survey of adult physical dysfunction settings. American Journal of Occupational Therapy, 49, 428–436.
22.
VelozoC.KielhofnerG.GernA.LinF. L.AzharF.LaiJ. S.. (1999). Worker Role Interview: Validation of a psychosocial work-related measure. Journal of Occupational Rehabilitation, 9, 153–168.
23.
VelozoC.KielhofnerG.LaiJ. S. (1999). The use of Rasch analysis to produce scale-free measurement of functional ability. American Journal of Occupational Therapy, 53, 83–89.
24.
WrightB.LinacreJ. (1989). Observations are always ordinal; measurements, however, must be interval. Archives of Physical Medicine and Rehabilitation, 70, 857–860.
25.
WrightB.StoneM. (1979). Best test design. Chicago: MESA Press.
26.
WrightB. D.MastersG. N. (1982). Rating scale analysis. Chicago: MESA Press.
