Jain 1987

Methods	Randomised controlled trial.
Participants	Male and female patients (distribution not stated) who had given consent. PEG tube inserted for CVA (n= 53), oropharyngeal cancer (n= 27), CNS trauma (n= 8), CNS infection (n= 3), CNS degenerative disease (n= 10) and miscellaneous (n= 6). Excluded if: allergic to cefazolin, refused signed consent, technical reasons for PEG placement. Total number of patients randomised; n = 107.
Interventions	Technique not stated, but presumed to be 'pull' as the authors state 'the feeding tube traverses the mouth and pharynx'. Group 1: receiving antibiotics before and during the study and were randomly assigned to: Group 1 a: cefazolin 1 g IV 30 min prior to PEG (n = 25); Group 1 b: saline placebo IV 30 min prior to PEG (n = 27); Group 2 not receiving antibiotics were randomly assigned to: Group 2 a: cefazolin 1 g IV 30 min prior to PEG (n = 27); Group 2 b: saline placebo IV 30 min prior to PEG (n = 28).
Outcomes	Peristomal infection.
Notes	Criteria for wound assessment scoring devised by Jain et al which used indicators previously used by Shapiro et al (1982). Group 1 excluded from grouped analysis. Country of origin: USA. Power calculation performed.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation schedule generated by Hewlitt‐Packard HP‐67 pocket calculator.
Allocation concealment (selection bias)	Low risk	One author (KPC) was responsible for (and the only one aware of) assignment and did not evaluate the wounds.
Blinding (performance bias and detection bias) Blinding patient	Low risk	Stated as 'double blind'.
Blinding (performance bias and detection bias) Blinding care provider	Low risk	Stated as 'double blind'.
Blinding (performance bias and detection bias) Blinding outcome assessor	Low risk	Outcomes assessed by team members blind to placebo allocation.
Incomplete outcome data (attrition bias) Drop outs/withdrawals	Low risk	No drop outs.
Selective reporting (reporting bias)	Low risk	Prespecified outcomes addressed.
Baseline imbalance? (Was the study free of baseline imbalance?)	Unclear risk	All groups were balanced for gender, underlying conditions, reasons for PEG. In group 1 the mean age was slightly but significantly less than that of patients who did not receive prophylaxis.
Timing of outcome assessment similar in all groups?	Low risk	Outcomes in all groups were assessed daily for seven days.