Table 2 Methodological characteristics of studies.
From: Systematic review and meta-analysis: influence of smoking cessation on incidence of pneumonia in HIV
Author (year) | Study design | Exposure assessment | Outcome assessment | Number of confounders controlled | Study quality score | |||
|---|---|---|---|---|---|---|---|---|
| Â | Â | Definition of smoking | Definition of non smoking | Method of assessingsmoking status | Definition ofpneumonia | Blinding ofassessors toexposure status (cohort studies) | Â | Â |
Bacterial pneumonia | ||||||||
[12] | Case control | >1 cig/day | Never smoked | Medical history | 2 | 0 | 3 | 7 |
[21] | Cohort | NR | Former and never, otherwise undefined | Questionnaire or clinical notes | 1 | 0 | 4 | 5 |
[13] | Nested case-control | NR | NR | NR | 2 | 1 | 0 | 3 |
[23] | Cohort | NR | NR | Interview | 2 | 1 | 4 | 7 |
[14] | Cohort | NR | Never smokers <100 cigarettes in lifetime | NR | 2 | 0 | 4 | 6 |
[15] | Cohort | NR | Not current smokers | NR | 2 | 0 | 7 | 9 |
[16] | Cohort | NR | NR | Questionnaire | 2 | 0 | 4 | 6 |
[17] | Cohort | NR | NR | Questionnaire | 2 | 0 | 0 | 2 |
[18] | Case control | >6 cigs/day | NR | NR | 2 | 0 | 0 | 3 |
Bacterial pneumonia and Pneumocystis jiroveci pneumonia | ||||||||
[19] | Cohort | NR | Self-defined | Clinical notes | 0 | 0 | 4 | 4 |
[20] | Cohort | Cigarettes/day in multiple categories | NR | Questionnaire | 1 | 0 | 0 | 2 |
[25] | Case control | NR | NR | Questionnaire | 2 | 0 | 3 | 5 |
Pneumocystis jiroveci pneumonia only | ||||||||
[22] | Cohort | Defined according to daily cigarette consumption and change in smoking status over time | Not currently smoking | Questionnaire | 2 | 0 | 2 | 6 |
[24] | Case control | Current tobacco use | Current non-smoking | Questionnaire and clinical notes | 2 | 0 | 1 | 4 |