Critical appraisal of confounding factors of observational studies on the association between dentofacial features and dental trauma in a Brazilian population

Abstract

Dental trauma is a highly prevalent dental emergency. Children and adolescents without inadequate lip coverage, increased overjet, and anterior open bite are associated with the occurrence of traumatic dental injuries. Observational studies do not allow the inference of causality, one of the reasons being: the potential confounding factors. Therefore, this review aimed to critically appraise the confounding factors considered in epidemiological studies that associate dentofacial features with the occurrence of dental trauma in Brazilian children and adolescents. Studies included in the qualitative synthesis of a recently published comprehensive systematic review and meta-analysis on the topic were screened. Studies that only mentioned the performance of bivariate analyzes or that did not mention the performance of multivariate analyzes were excluded. Evaluation of control statements for possible confounders and bias consideration was performed for each selected study. Confounding factors in these studies were also identified and categorized according to their domains. Fifty-five observational studies were screened, of which 11 were excluded due to the mention of only bivariate analyzes or the lack of multivariate analyses. The remaining 44 studies were critically appraised. Of these, 9 studies specifically mentioned the term confounding, and 12 studies mentioned the term bias. However, only 14 studies mentioned limitations on confounding factors in their findings. Among the 99 different variables identified, the most used were type of trauma, followed by sex and age. Most studies did not acknowledge the control for possible confounding factors and rarely stressed the need for caution in interpreting their results. Cross-sectional studies do not allow inferring a cause-and-effect relationship between dentofacial features and dental trauma.