Table 2: Changes in overall call volume and number of new callers per month before and after new policy for health warning labels, and with and without effect of promotion campaign and January effect*
VariableOverall call volume,
mean (95% CI)†		No. of new callers,
mean (95% CI)†
New policy for health warning labels‡
Before policy1043 (868-1218)185 (146-224)
After policy1591 (1355-1827)334 (288-380)
Difference, %52.580.5
Promotion campaign (Driven to Quit Challenge)§
During months without campaign1246 (1086-1407)246 (209-283)
During months with campaign2016 (1783-2248)363 (226-500)
Difference, %61.847.5
January effect
During months excluding January1287 (1113-1461)247 (209-286)
During months including January1376 (1234-1518)318 (252-384)
Difference, %6.928.7

Note: CI = confidence interval.

*Seasonal phenomenon where people decide to make lifestyle changes such as stopping smoking as a New Year's resolution.

†Unless stated otherwise.

‡Unadjusted for the effects of promotion campaign and January effect.

§Driven to Quit Challenge campaign was held in February 2010, 2011 and 2012, but not in February 2013.