| Organism of interest1 | Any organism |
|---|---|
| Case | Case |
| ICD‐9‐CM coding for pneumonia (includes all bacterial PNU codes) AND positive respiratory culture with an organism of interest | ICD‐9‐CM coding for pneumonia (includes all PNU codes) AND positive respiratory culture with any organism |
| Control | Control |
| No ICD‐9‐CM code for pneumonia AND No respiratory culture performed or a negative respiratory culture | No ICD‐9‐CM code for pneumonia AND No respiratory culture performed or a negative respiratory culture |
| Noncase, noncontrol | Noncase, noncontrol |
| ICD‐9‐CM code for pneumonia and positive respiratory culture for an organism NOT of interest OR ICD‐9‐CM code for pneumonia and no positive respiratory culture performed or negative respiratory culture OR No ICD‐9‐CM code for bacterial pneumonia + positive respiratory culture for any organism OR No ICD‐9‐CM code for bacterial pneumonia + positive urine streptococcal antigen | ICD‐9‐CM code for pneumonia and no positive respiratory culture performed OR negative respiratory culture OR No ICD‐9‐CM code for pneumonia + positive respiratory culture for any organism OR No ICD‐9‐CM code for pneumonia + Positive urine streptococcal antigen |
Notes: 1Organisms of interest are Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalis, Enterococcus faecium, Pseudomonas aeruginosa, Acinetobacter baumannii, Streptococcus pneumoniae. 2A common skin contaminant must be cultured from two or more blood cultures drawn on separate occasions within 2 days of each other to count as positive culture. Common skin contaminants in blood culture include diphtheroids (Corynebacterium spp.), Bacillus (not B. anthracis) spp., Propionibacterium spp., coagulase‐negative staphylococci (including S. epidermidis), viridans group streptococci, Aerococcus spp., Micrococcus spp.). 3NHSN, National Healthcare Safety Network.