Clinical Orthopaedics and Related Research®

, Volume 471, Issue 11, pp 3679–3686

Have Levels of Evidence Improved the Quality of Orthopaedic Research?

  • Brian P. Cunningham
  • Samuel Harmsen
  • Chris Kweon
  • Jason Patterson
  • Robert Waldrop
  • Alex McLaren
  • Ryan McLemore
Clinical Research

DOI: 10.1007/s11999-013-3159-4

Cite this article as:
Cunningham, B.P., Harmsen, S., Kweon, C. et al. Clin Orthop Relat Res (2013) 471: 3679. doi:10.1007/s11999-013-3159-4

Abstract

Background

Since 2003 many orthopaedic journals have adopted grading systems for levels of evidence (LOE). It is unclear if the quality of orthopaedic literature has changed since LOE was introduced.

Questions/purposes

We asked three questions: (1) Have the overall number and proportion of Level I and II studies increased in the orthopaedic literature since the introduction of LOE? (2) Is a similar pattern seen in individual orthopaedic subspecialty journals? (3) What is the interobserver reliability of grading LOE?

Methods

We assigned LOE to therapeutic studies published in 2000, 2005, and 2010 in eight major orthopaedic subspecialty journals. Number and proportion of Level I and II publications were determined. Data were evaluated using log-linear models. Twenty-six reviewers (13 residents and 13 attendings) graded LOE of 20 blinded therapeutic articles from the Journal of Bone and Joint Surgery for 2009. Interobserver agreement relative to the Journal of Bone and Joint Surgery was assessed using a weighted kappa.

Results

The total number of Level I and II publications in subspecialty journals increased from 150 in 2000 to 239 in 2010. The proportion of high-quality publications increased with time (p < 0.001). All subspecialty journals other than the Journal of Pediatric Orthopaedics and the Journal of Orthopaedic Trauma showed a similar behavior. Average weighted kappa was 0.791 for residents and 0.842 for faculty (p = 0.209).

Conclusions

The number and proportion of Level I and II publications have increased. LOE can be graded reliably with high interobserver agreement. The number and proportion of high-level studies should continue to increase.

Copyright information

© The Association of Bone and Joint Surgeons® 2013

Authors and Affiliations

  • Brian P. Cunningham
    • 1
  • Samuel Harmsen
    • 1
  • Chris Kweon
    • 1
  • Jason Patterson
    • 1
  • Robert Waldrop
    • 1
  • Alex McLaren
    • 1
  • Ryan McLemore
    • 1
  1. 1.Orthopaedic ResidencyBanner Good Samaritan Medical CenterPhoenixUSA