HOW OFTEN ARE STUDY DESIGN AND LEVEL OF EVIDENCE MISREPORTED IN THE PEDIATRIC ORTHOPAEDIC LITERATURE?

Abstract

Background:

Observational studies are the most commonly employed study designs in the pediatric orthopaedic literature. The differences between observational study designs are important but not widely understood, leading to potential discrepancies between the reported and actual study design. Study design misclassification is associated with a potential for misreporting level of evidence (LOE).

Purpose:

To determine the degree of study design and LOE misclassification in the pediatric orthopaedic literature.

Methods:

The Institute for Scientific Information (ISI) Web of Science was queried to identify all pediatric orthopaedic observational studies published from 2014-2017. Reported study design and LOE were recorded for each study. The actual study design and LOE were determined based on established clinical epidemiological criteria by reviewers with advanced epidemiological training. Studies with a discrepancy between reported and actual study design and LOE were identified. The following covariates were recorded for each study: subspecialty, inclusion of a statistician coauthor, sample size, journal, and journal impact factor. Chi-square analysis was used to identify factors associated with study design and LOE misreporting.

Results:

One thousand articles were screened, yielding 647 observational studies. Three hundred thirty-five publications (52%) did not clearly report a study design in either the abstract or manuscript text. Of those that did, 59/312 (19%) reported the incorrect study design (Figure 1). The largest discrepancy was in the 109 studies that were reported to be case series, among which 30 (27.5%) were actually retrospective cohort studies. Three hundred thirteen publications (48%) did not report a LOE. Of those that did, 95/334 (28%) reported the incorrect LOE (Figure 2). Thirty-three studies (19%) reported a LOE that was higher than the actual LOE and 62 (35%) under-reported the LOE.

Conclusion:

The majority of observational pediatric orthopaedic studies either did not report a study design or reported the wrong study design. Similarly, the majority of studies did not report or misreported their LOE. Greater epidemiological rigor in classifying and evaluating observational studies is required on the part of investigators, reviewers, and journal editors.

Figure 1.

Sankey diagram demonstrating directions of study design misclassification.

Figure 2.

Sankey diagram demonstrating directions of level of evidence misclassification.