| Methods |
RCT |
| Participants |
Young adult gold miners in South Africa (recruited within 1 day of arrival) |
| Interventions |
6‐valent PPV (n = 983), or meningococcal group A vaccine (n = 1051), or saline (n = 985). Total control n = 2036 |
| Outcomes |
A2. Pneumonia (all causes)
A7. Presumptive pneumococcal pneumonia
A8. Presumptive pneumococcal pneumonia (vaccine‐type) |
| Notes |
Mean length of follow‐up not stated
Recruited between February 1973 to June 1974, with follow‐up until May 1975
Maximum duration of follow‐up 2.3 years |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Method not described |
| Allocation concealment (selection bias) |
Unclear risk |
Method not described |
| Confounding
All outcomes |
Unclear risk |
NA |
| Blinding of participants and personnel (performance bias)
All outcomes |
Unclear risk |
Not specified |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
"Clinical observations were made blindly without knowledge of whether the subject had received pneumococcal vaccine or control material" |
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
Not described |
| Selective reporting (reporting bias) |
Unclear risk |
Not described |
