2.

纳入研究16篇文献的质量评价（STROBE声明）

STROBE Statement-checklist criteria included in 16 reports of passive smoking and lung cancer risk

Items	Recommendations	Number of study[n (%)]
Title and abstract	1.1 Indicate the study’s design with a commonly used term in the title or the abstract	4 (25%)
	1.2 Provide in the abstract an informative and balanced summary of what was done	12 (75%)
Introduction
Background/rationale	2 Explain the scientific background and rationale for the investigation being reported	13 (81.3%)
Objectives	3 State specific objectives, including any prespecified hypotheses	14 (87.5%)
Methods
Stydy desin	4 Present key elemens of study design early in the paper	12 (75%)
Setting	5 Describe the setting, locations, and relevant dates, including periods of recruitment,	16 (100.0%)
Participants	6.1 Give the eligibility criteria, and the sources and methods of ascertainment, and	11 (68.6%)
	6.2 For matched studies, give matching criteria and the number of controls per case	9 (56.3%)
Variables	7 Clearly define all outcomes, exposures, predictors, potential confounders, and effect	8 (50.0%)
Datasources/	8 For each variable of interest, give sources of data and details of methods of	10 (62.5%)
Bias	9 Describe any efforts to address potential sources of bias	2 (12.5%)
Study size	10 Explain how the study size was arrived at	0 (0)
Quantitative variables	11 Explain how quantitative variables were handled in the analyses. If applicable,	9 (56.3%)
	12.1 Describe all statistical methods, including those used to control for confounding	14 (87.5%)
	12.2 Describe any methods used to examine subgroups and interactions	11 (68.8%)
Statistical methods	12.3 Explain how missing data were addressed	4 (25%)
	12.4 If applicable, explain how matching of cases and controls was addressed	6 (37.5%)
	12.5 Describe any sensitivity analyses	4 (25%)
Results
	13.1 Report numbers of individuals at each stage of study-eg numbers potentially	13 (81.3%)
Participants	13.2 Give reasons for non-participation at each stage	8 (50%)
	13.3 Consider use of a flow diagram	0 (0)
Descriptive data	14.1 Give characteristics of study participants (eg, demographic, clinical, social) and	11 (68.8%)
	14.2 Indicate number of participants with missing data for each variable of interest	5 (31.3%)
Outcome data	15 Report numbers in each exposure category, or summary measures of exposure	13 (81.3%)
	16.1 Give unadjusted estimates and, if applicable, confounder-adjusted estimates	12 (75%)
	16.2 Report category boundaries when continuous variables were categorized	11 (68.8%)
	16.3 If relevant, consider translating estimates of relative risk into absolute risk for a	3 (18.8%)
Other analyses	17 Report other analyses done-eg analyses of subgroups and interactions, and	5 (31.3%)
Discusion
Key results	18 Summarise key results with reference to study objectives	16 (100%)
Limitations	19 Discuss limitations of the study, taking into account sources of potential bias or	9 (56.3%)
Interpretation	20 Give a cautious overall interpretation of results considering objectives, limitations,	11 (68.8%)
Generalisability	21 Discuss the generalisability (external validity) of the study results	5 (31.3%)
Other information
Funding	22 Give the source of funding and the role of the funders for the present study and,	2 (12.5%)
	if applicable, for the original study on which the present article is based