Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Jun;27(6):1984-1991.
doi: 10.1007/s00167-018-5109-x. Epub 2018 Aug 21.

Rasch analysis of the Forgotten Joint Score in patients undergoing knee arthroplasty

Didier D Niama Natta  1 , Emmanuel Thienpont  2   3 , Alexandre Bredin  2 , Gwenael Salaun  2 , Christine Detrembleur  4
Affiliations

Rasch analysis of the Forgotten Joint Score in patients undergoing knee arthroplasty

Didier D Niama Natta et al. Knee Surg Sports Traumatol Arthrosc. 2019 Jun.

Abstract

Purpose: The purpose of this study was to test the hypothesis that the "Forgotten Joint Score" (FJS-12) is a unidimensional interval-level scale. Unidimensionality refers to measuring a single attribute, i.e., the single ability to forget the arthroplasty. If this property is not verified, the interpretation of the score can be confusing. Unidimensionality is an essential prerequisite of construct validity and required if FJS-12 response data are to be validly summated into a single score. Interval-level dimension is an essential prerequisite of the parametric statistics. Rasch analysis was used to test our study hypothesis.

Methods: The FJS-12 questionnaire was validated in 248 unilateral knee arthroplasty patients. Successive analyses were used to select items with good psychometric qualities to constitute the new "FJS". The external validity was assessed with the KUJALA questionnaire.

Results: Quantity of relevant items was greater than 50%. Of the 12 original items, nine showed disturbed thresholds, indicating that patients were unable to discriminate among the five levels for these items. The data set was reanalyzed using a four-level scale. The new analysis indicated that the internal consistency was good (r = 0.84). Three items did not fit with the model and they were removed. The nine items of the final scale defined a unidimensional and linear measure of the forgotten joint, and showed a continuous progression in their difficulty. The perception of difficulty was group-independent. The correlation coefficient was moderate between FJS and KUJALA score (r = 0.4).

Conclusions: This new and items reduced FJS can be used in clinical practice with good psychometric qualities. It provides a reliable tool to follow up patient's evolution and document changes related to knee arthroplasty. This valid FJS is needed in evaluating patients' assessment, one indicator of quality of care.

Level of evidence: III-Therapeutic.

Keywords: Awareness joint; FJS-12 score; Rash model; Total knee arthroplasty.

PubMed Disclaimer

References

    1. Arch Phys Med Rehabil. 2000 Dec;81(12 Suppl 2):S15-20 - PubMed
    1. J Appl Meas. 2002;3(2):205-31 - PubMed
    1. Neuromuscul Disord. 2007 Jun;17(6):459-69 - PubMed
    1. Br J Clin Psychol. 2007 Mar;46(Pt 1):1-18 - PubMed
    1. J Bone Joint Surg Br. 2007 Jul;89(7):893-900 - PubMed