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
. 2021 Mar 26;6(1):e20.00164.
doi: 10.2106/JBJS.OA.20.00164. eCollection 2021 Jan-Mar.

Two-Year Recall Bias After ACL Reconstruction Is Affected by Clinical Result

Per-Henrik Randsborg  1 , Dakota Adamec  1 , Nicholas A Cepeda  1 , Daphne I Ling  1   2
Affiliations

Two-Year Recall Bias After ACL Reconstruction Is Affected by Clinical Result

Per-Henrik Randsborg et al. JB JS Open Access. .

Abstract

Recall bias is a systematic error caused by inaccuracy in reporting past health status and can be a substantial methodological flaw in the retrospective collection of data. Little is known about recall bias following anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to evaluate patients' recall bias regarding preinjury knee function at 2 years after ACLR.

Methods: Patients undergoing ACLR were enrolled in an institutional ACL registry. Preoperatively and at 2 years postoperatively, patients quantified their preinjury knee function on a scale of 0 to 10 (10 = best). Recall bias was quantified as the difference in the reported preinjury function between the 2 time points. The clinical result of ACLR was evaluated according to the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation score. Patients meeting the minimal clinically important difference (MCID) in the IKDC score were considered to have had a good outcome, while patients who did not reach the MCID were considered to have had failure of treatment. Recall bias was compared between the 2 groups.

Results: Of 2,109 patients enrolled in the registry, 1,219 were included in the study. Patients with a good outcome remembered their preinjury knee function on a 0-to-10 scale to be better than what they reported at baseline, by a mean difference of 0.40 points (95% confidence interval [CI], 0.22 to 0.58 points). The recall bias was stronger for patients with a poor outcome, who remembered their knee function to be worse than reported at baseline, by a mean difference of -0.81 (95% CI, -1.4 to -0.26). The mean difference in recall between the 2 groups was -1.21 (95% CI, -1.74 to -0.67) (p < 0.0001).

Conclusions: The recall bias of preinjury knee function following ACLR was small and not clinically meaningful for the majority of patients. However, patients with a poor outcome had a clinically relevant and significant recall bias.

Clinical relevance: Our findings suggest that patients with a poor outcome have a substantial recall bias. This has clinical relevance when considering treatment effects of revision surgery, whereby the clinical benefit of the treatment might be affected by recall bias.

PubMed Disclaimer

Conflict of interest statement

Disclosure: The authors indicated that no external funding was received for any aspect of this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSOA/A264).

References

    1. Coughlin SS. Recall bias in epidemiologic studies. J Clin Epidemiol. 1990;43(1):87-91. - PubMed
    1. Neugebauer R, Ng S. Differential recall as a source of bias in epidemiologic research. J Clin Epidemiol. 1990;43(12):1337-41. - PubMed
    1. Granan LP, Bahr R, Steindal K, Furnes O, Engebretsen L. Development of a national cruciate ligament surgery registry: the Norwegian National Knee Ligament Registry. Am J Sports Med. 2008February;36(2):308-15. Epub 2007 Nov 7. - PubMed
    1. van Meer BL, Meuffels DE, Vissers MM, Bierma-Zeinstra SM, Verhaar JA, Terwee CB, Reijman M. Knee injury and Osteoarthritis Outcome Score or International Knee Documentation Committee Subjective Knee Form: which questionnaire is most useful to monitor patients with an anterior cruciate ligament rupture in the short term? Arthroscopy. 2013April;29(4):701-15. Epub 2013 Feb 8. - PubMed
    1. Williams T, Burley D, Evans L, Robertson A, Hardy L, Roy S, Lewis D. The structural validity of the IKDC and its relationship with quality of life following ACL reconstruction. Scand J Med Sci Sports. 2020September;30(9):1748-57. Epub 2020 Jun 25. - PubMed