Research shows the success of a bacterial community depends on its shape.
In the four years since voters approved a cigarette tax increase to fund a Massachusetts anti-smoking campaign, per-capita cigarette consumption has fallen more than three times faster than in the 48 other states which don't have such a program, according to research reported by scientists including Dr. Jeffrey Harris, associate professor of economics.
Dr. Harris and health officials in three states compared the number of cigarettes taxed per capita in Massachusetts during periods before and after the 25-cent-per-pack tax increase went into effect in January 1993. The resulting revenue was used to establish the Massachusetts Tobacco Control Program (MTCP) administered by the Department of Public Health, as stipulated in Question 1 on the November 1992 ballot.
Dr. Harris's work was reported in the November 8 Morbidity and Mortality Weekly Report issued by the Centers for Disease Control and Prevention. The article was one of three published in that edition to coincide with the 20th anniversary on November 21 of the American Cancer Society's "Great American Smoke-Out" where smokers are encouraged to quit for at least a day.
In October 1993, the MTCP launched a statewide mass-media anti-smoking campaign. It subsequently funded local boards of health and school departments to promote policies aimed at reducing the public's exposure to tobacco smoke and to restrict youth access to cigarettes. Money also went to health education programs, primary-care providers and services to help smokers quit.
The CDCP and the Massachusetts health department gathered information about the number of cigarettes taxed per capita and the prevalence of smoking during 1990-92 and 1993-96. They then compared these figures with data from California (where a similar voter-mandated cigarette tax hike went into effect in 1989) and the rest of the country.
Results showed that Massachusetts per-capita cigarette consumption has dropped by almost 20 percent since 1992, compared to 15 percent in California and just 6 percent in the other 48 states and the District of Columbia. In comparing 1990-92 and 1993-95, the prevalence of adult smoking declined at similar rates in Massachusetts (by 2.2 percentage points, to 21.3 percent) and California (by 2.7 percentage points, to 17.4 percent), but by only about 0.8 percentage points (to 23.4 percent) for 41 other states combined.
In contrast, from 1990-92 before the tax increase, consumption declined only 6.4 percent in Massachusetts, vs. 11 percent in California and 5.8 percent in the rest of the country.
"We don't think this [recent] decline was the result simply of increased cross-border purchases," Dr. Harris said. Cigarette taxes in Connecticut and Rhode Island were raised in 1993-94 to levels comparable to that in Massachusetts. Prices declined and consumption rose in New Hampshire, but even if that entire increase were due to purchases by Massachusetts smokers, the per-capita smoking decrease in this state from 1992-96 would still have been 17 percent.
The tax increase combined with the mass-media campaign "appears to have produced a greater reduction in cigarette consumption than an increase in taxes would have produced alone," Dr. Harris said. The smoking decline was found even though there was a drop and subsequent stabilization in average cigarette prices starting in mid-1993, when manufacturers began marketing more discount brands.
"Tax increases have immediate effects, but anti-smoking campaigns can take years to show their full impact," he added. "So far, the evidence suggests that there may be 100,000 fewer adult smokers in the state, but we'll be doing more investigations and additional research papers."
A version of this article appeared in MIT Tech Talk on November 13, 1996.