Kristoffersen 2009

Methods	Randomised clinical trial, multicentre, 3 hospitals in Denmark
Participants	Inclusion criteria: hospitalised patients with suspected pneumonia (no X‐ray confirmation); quote: "The assessment of eligibility (i.e. the clinical diagnosis) was made by the admitting physician and was based on medical history and physical examination." Exclusion criteria: not meeting the diagnostic criteria Included in this analysis: 210 out of 223 randomised patients: 13 post randomisation exclusions (3 no procalcitonin testing, 6 not meeting inclusion criteria, 4 withdrew informed consent)
Interventions	Guiding antibiotic decisions in CAP patients with initial values only Algorithm used in this study: physicians were not asked to wait for procalcitonin results before initiating antimicrobial therapy; therefore, procalcitonin values were, in most cases, used to motivate either cessation or continuation of already initiated treatments. Discontinuation of AB treatment was recommended if procalcitonin at admission was below 0.25 µg/L, despite delays in test results
Outcomes	Antibiotic use Mortality ICU admission
Notes	Funding: The Danish Medical Research Council and the Danish Lung Association provided financial support Follow‐up: until hospital discharge Registration: NCT00415753
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation scheme
Allocation concealment (selection bias)	Low risk	Central randomisation
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Open‐label trial where physicians knew in which group patients were and where procalcitonin levels were only communicated in the intervention arm
Blinding of outcome assessment (detection bias) All outcomes	High risk	Non‐blinded study members
Incomplete outcome data (attrition bias) All outcomes	Low risk	Follow‐up for mortality: 210/210 (100% until discharge)
Selective reporting (reporting bias)	Low risk	No selective reporting (oral verification with first author)
Other bias	Unclear risk	59% adherence to procalcitonin algorithm in procalcitonin group