It is useful to note that in ALL studies about primary and passive smoking, the following terminology is almost exclusively used before statements:

• "Suggests"
• "Seems"
• "Appears"
• "Infers"
• "Should"
• "Would"
• "Could"
• "Assumes"
• "Suspects"
• "Maybe"
• "Perhaps"
• "Supposed"
• "Possible"
• "Probable"
• "Likely"
• "Conceivable"
• "May"

...And many other similar words. There is NEVER a conclusive statement -- except when filtered by the propaganda machine for political purposes.