| Methods |
Double‐blind RCT |
| Participants |
Non‐immunocompromised adults aged 50 to 85 years who had been inpatients for CAP in Sweden. Potential participants excluded if assumed poor compliance, previous receipt of PPV, allergy to PPV or immunocompromised |
| Interventions |
23‐valent PPV (n = 339) administered intramuscularly (subcutaneous for patients on anticoagulant therapy), or saline placebo (352) |
| Outcomes |
A1. IPD
A2. Pneumonia (all causes)
A3. Mortality (all causes)
A4. IPD (vaccine‐type)
A5. Definitive pneumococcal pneumonia
A6. Definitive pneumococcal pneumonia (vaccine‐type)
A7. Presumptive pneumococcal pneumonia
A8. Presumptive pneumococcal pneumonia (vaccine‐type)
A9. Mortality due to pneumonia |
| Notes |
Average follow‐up 2.5 years
Case ascertainment: participant to contact doctor if temperature above 38 C or cause to suspect pneumonia recurrence. 1 participant withdrawn (n = 2, as randomised twice) |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Specific method not described, however, text states: "randomisation was done by the vaccine manufacturer and the code was not disclosed until follow‐up had ended" |
| Allocation concealment (selection bias) |
Low risk |
Vaccine and placebo were marked with random numbers |
| Confounding
All outcomes |
Unclear risk |
NA |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
Staff and participants blinded |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
Outcome assessors did not know participant study group allocation |
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
No evidence of incomplete outcome data |
| Selective reporting (reporting bias) |
Unclear risk |
No evidence of selective outcome reporting |
