Study	Reason for exclusion
Adeboyeku 2011	Comparison of twice daily vs three times daily antibiotics, not single vs combination.
Al‐Ansari 2006	Comparison of once vs multiple daily dosing, not single vs combination.
Aminimanizani 2002	Comparison of single vs multiple daily dosing, not single vs combination.
Balsamo 1986	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Beaudry 1980	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Beringer 2012	Not a comparison of single vs combination antibiotics; a comparison of a single intravenous dose of an antibiotic and multiple oral doses of the same antibiotic.
Blumer 2005	Comparison of two combination regimens.
Bosso 1988	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Church 1997	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Conway 1997	Comparison of colistin with multiple antibiotic combinations.
De Boeck 1989	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
De Boeck 1999	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Donati 1987	Home vs hospital therapy, not single vs combination.
Gold 1985	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Hatziagorou 2013	Not a comparison of a single vs combination antibiotics; evaluation of tool to assess treatment response in children.
Hoogkamp 1983	Non‐randomised study: first 7 participants allocated to single treatment; next 7 to combination treatment with marked differences in baseline characteristics.
Hubert 2009	Comparison of intermittent vs continuous infusions, not single vs combination.
Hyatt 1981	Comparison of anti‐staphylococcal drug (oxacillin) vs oxacillin plus 2 anti‐pseudomonal drugs.
Jewett 1985	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Keel 2011	Not a comparison of a single vs combination antibiotic; comparison of intravenous and oral versions of the same agent.
Kenny 2009	Study of eradication of Pseudomonas aeruginosa, not a comparison of single vs combination.
Krause 1979	Pseudo‐randomised study. Treatment and comparison groups were not sufficiently similar at baseline.
Kuni 1992	Not a comparison of single vs combination antibiotics.
Levy 1982	Comparison of 2 single agents.
McCabe 2013	Not a comparison of single vs combination antibiotics; evaluation of a twice‐daily tobramycin regimen.
Nelson 1985	Review article on single vs combination antibiotic treatment, i.e. not an RCT.
Noah 2010	Inhaled vs systemic antibiotics.
Padoan 1987	Reported number of courses of treatment instead of number of people included. Some participants may have been counted twice or included in both treatment group therefore analysis unclear.
Permin 1983	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Prayle 2013	Not a comparison of single vs combination antibiotics; comparison of morning vs evening intravenous tobramycin.
Riethmueller 2009	Continuous vs intermittent infusions.
Roberts 1993	Randomisation method unclear ‐ participants appeared to have been randomised to single or combination therapy each morning using a cross‐over method.
Semykin 2010	Not a comparison of single vs combination antibiotics; trial of inhaled tobramycin therapy.
Stack 1985	Comparison of single agent compared with two other antibiotics (i.e. drug A vs drug B plus drug C).
Turner 2013	Not a comparison of single vs combination antibiotics; study of continuous vs intermittent infusion piperacillin‐tazobactam.
Wesley 1988	Comparison of single agent compared with 2 other antibiotics (i.e. drug A vs drug B plus drug C).
Whitehead 2002	Efficacy of once daily tobramycin, not a comparison of single vs combination agents.

CXR: chest X‐ray
 vs: versus