| Methods |
Randomised controlled trial, unit of randomisation = bar. |
| Participants |
Bars in South Wales, West Midlands, West of England; UK.
Experimental group = 30 bars
Control = 23 bars |
| Interventions |
Complete replacement of pint glasses;
Experimental = toughened glassware,
Control = annealed glassware. |
| Outcomes |
Injuries to bar staff, by self‐complete questionnaire. |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Unclear risk |
53 bars were randomly assigned to experimental (n=30, toughened glassware) and control (n=30, annealed glassware) groups. Method of randomisation was not reported. |
| Allocation concealment? |
Unclear risk |
No information. |
| Blinding?
All outcomes |
Low risk |
Bars did not know which glassware they were assigned to and researchers were blinded to allocation status. |
| Confounders |
Unclear risk |
Any differences in baseline characteristics between the two groups are not reported. |
| Data collection methods |
Unclear risk |
Injury data were collected over six months, by self‐completed questionnaire (distributed through bar managers), response rate is unknown. |
| Withdrawals & dropouts |
Unclear risk |
Four bars did not receive their allocated intervention and were excluded from the analysis. Nine bars in control and 14 in experimental were lost to follow‐up. |
| Intervention integrity |
Unclear risk |
Whole stock of pint glassware was replaced. |
| Duration of follow‐up |
Unclear risk |
Total of 1229 (653 experimental and 576 control) questionnaires were completed and returned. |
