Additional file 2: of Frequency and impact of confounding by indication and healthy vaccinee bias in observational studies assessing influenza vaccine effectiveness: a systematic review

Search strategy for the systematic review on frequency and impact of selection bias in observational studies on influenza vaccine effectiveness. (DOCX 21 kb

Additional file 3: of Frequency and impact of confounding by indication and healthy vaccinee bias in observational studies assessing influenza vaccine effectiveness: a systematic review

List of excluded studies. (DOCX 147 kb

Additional file 1: of Use of existing systematic reviews for evidence assessments in infectious disease prevention: a comparative case study

Case study A: flow chart for the systematic literature search and study selection. (DOCX 87 kb

Additional file 1 of Strengthening the role of hospital leadership in infection control (LEAD-IC) – a multimodal educational intervention in German acute care hospitals

Additional file 1. LEAD-IC short evaluation questionnaire

Effectiveness of the 23-Valent Pneumococcal Polysaccharide Vaccine (PPV23) against Pneumococcal Disease in the Elderly: Systematic Review and Meta-Analysis

<div><p>Background</p><p>Routine vaccination of elderly people against pneumococcal diseases is recommended in many countries. National guidelines differ, recommending either the 23-valent polysaccharide vaccine (PPV23), the 13-valent conjugate vaccine (PCV13) or both. Considering the ongoing debate on the effectiveness of PPV23, we performed a systematic literature review and meta-analysis of the vaccine efficacy/effectiveness (VE) of PPV23 against invasive pneumococcal disease (IPD) and pneumococcal pneumonia in adults aged ≥60 years living in industrialized countries.</p><p>Methods</p><p>We searched for pertinent clinical trials and observational studies in databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. We assessed the risk of bias of individual studies using the Cochrane Risk of Bias tool for randomized controlled trials and the Newcastle-Ottawa Scale for observational studies. We rated the overall quality of the evidence by GRADE criteria. We performed meta-analyses of studies grouped by outcome and study design using random-effects models. We applied a sensitivity analysis excluding studies with high risk of bias.</p><p>Results</p><p>We identified 17 eligible studies. Pooled VE against IPD (by any serotype) was 73% (95%CI: 10–92%) in four clinical trials, 45% (95%CI: 15–65%) in three cohort studies, and 59% (95%CI: 35–74%) in three case-control studies. After excluding studies with high risk of bias, pooled VE against pneumococcal pneumonia (by any serotype) was 64% (95%CI: 35–80%) in two clinical trials and 48% (95%CI: 25–63%) in two cohort studies. Higher VE estimates in trials (follow-up ~2.5 years) than in observational studies (follow-up ~5 years) may indicate waning protection. Unlike previous meta-analyses, we excluded two trials with high risk of bias regarding the outcome pneumococcal pneumonia, because diagnosis was based on serologic methods with insufficient specificity.</p><p>Conclusions</p><p>Our meta-analysis revealed significant VE of PPV23 against both IPD and pneumococcal pneumonia <i>by any serotype</i> in the elderly, comparable to the efficacy of PCV13 against <i>vaccine-serotype</i> disease in a recent clinical trial in elderly people. Due to its broader serotype coverage and the decrease of PCV13 serotypes among adults resulting from routine infant immunization with PCV13, PPV23 continues to play an important role for protecting adults against IPD and pneumococcal pneumonia.</p></div

Forest plots of meta-analyses of observational studies, outcome IPD.

<p>IPD = invasive pneumococcal disease</p> <p>VT-IPD = vaccine-serotype IPD.</p

Forest plots of meta-analyses of observational studies, outcome pneumococcal pneumonia.

<p>PP = pneumococcal pneumonia.</p

PICOS criteria for eligibility of studies.

PICOS criteria for eligibility of studies.</p

Characteristics of studies included in the systematic review of PPV23 efficacy/effectiveness.

<p>Characteristics of studies included in the systematic review of PPV23 efficacy/effectiveness.</p