Comparability
Changes in the universe and response categories may affect comparability. The 1992 survey allowed respondents to either agree or disagree that smoking should not be allowed in indoor public spaces, while the 2000 survey allowed respondents to state that smoking should be allowed in all, some, or no indoor public spaces.
Changes in survey design (e.g., quarters in which the supplement was collected) may affect raw frequencies. As always, data users should use the prescribed IHIS weights.
