Stroke: The Elixhauser Index for Comorbidity Adjustment of in-Hospital Case Fatality

I read with interest the article by Zhu et al.1 However, I did not see that any screening for dysphagia or aspiration pneumonia was made. If this search was made, it is possible that the population was excluded. If this screening was not done and this was added using ICD (9 or 10) search terms for dysphagia (787.20) or aspiration pneumonia (507.0), what impact …