Amortegui 1978.

Study characteristics
Methods	Cross‐over clinical trial
Participants	The actual number of nurses and neonates recruited was unclear because it was not mentioned; however, "a total of 1806 cultures were evaluated and data were reported as counts. The number of nurses involved fluctuated between 4 and 6 in each nursery, according to the baby census".  This study did not contribute any data to our outcomes of interest. Inclusion criteria Setting: 2 well‐baby nurseries were selected, at Magee Women's Hospital, Pittsburgh, Pennsylvania, USA, between October 1974 and March 1975. Country: USA Health status: "Two well‐baby nurseries" Numbers: treatment (unclear); control (unclear) ["The number of nurses involved fluctuated between 4 and 6 in each nursery, according to the baby census"] Age (mean ± SD) Treatment: not reported Control: not reported Sex (M/F) Treatment (M/F): not reported Control (M/F): not reported Exclusion criteria Not reported
Interventions	Treatment group Betadine surgical scrub Control group Prepodyne scrub
Outcomes	Nursing personnel hand colonisation Infants umbilical colonisation
Notes	A total of 1806 cultures were evaluated. The study was single‐blind to the nurses. Authors did not declare their funding source.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	No randomisation was applied. Quote: "both products were used alternatively for handwash in each of the two study nurseries in an effort to minimise nursery variation".
Allocation concealment (selection bias)	High risk	Not reported; probably not done
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	It was unclear what the study authors meant by (quote) "The study was single blinded to the nurses".
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Quote: "the cultures were interpreted by one of the technologists in the microbiology laboratory. This person was also involved in culture collection". It was not stated whether this person was blinded to the intervention.
Incomplete outcome data (attrition bias) All outcomes	Low risk	There was no report of attrition.
Selective reporting (reporting bias)	Unclear risk	We did not have access to the study protocol; it was unclear.
Other bias	High risk	The numbers of nurses and neonates involved in the study were not clearly stated. Also the study did not report if there was a washout period before participants crossed to a new intervention group.