Impact of the Walton report on cervical cancer screening programs in Canada.

It is almost 4 years since the Walton report on cervical cancer screening programs was published. In an effort to assess the impact of this report on such programs across Canada the Department of National Health and Welfare carried out a survey using questionnaires. It appears from the evaluation that physicians, laboratories and provincial departments of health are giving thoughtful but cautious consideration to implementing the report''s recommendations. Stated areas of controversy include the recommended frequency of cervical smear examination, the establishment of province-wide cytology registries and the recommended size of laboratories. Perhaps the pace will quicken as additional knowledge and experience are gained. Perhaps, too, if a national mechanism to encourage provincial implementation were instituted hesitancy would decrease.     

Cancer patterns in Canada.

Cancer is diagnosed in about 70 000 Canadians each year and is the leading cause of the loss of potential years of life before age 75 among women. Life-threatening forms of cancer will develop in at least one of every three Canadian newborns during their lifetimes if current cancer risks are not reduced. Lung and breast cancers are, respectively, the leading causes of premature death due to cancer among men and women. Compared with other countries Canada has low death rates for stomach cancer but high rates for certain smoking-related cancers (those of the lung and of the mouth and throat), leukemia and cancers of the colon, breast and lymphatic tissues. Newfoundland has the highest rates of death from stomach cancer and the lowest rates of death from prostatic cancer, whereas the western provinces have the opposite pattern. The rates of death from lung cancer among men are highest in Quebec, the province with the highest prevalence of smoking. In Canada the overall rates of death from cancer increased by 32% among men from 1951 to 1983. However, among women they declined by 12% from 1951 to 1976 and increased from 1976 to 1983, particularly among those aged 55 to 74. The rising rates of death due to lung cancer were primarily responsible for these increases. Lung cancer will likely displace breast cancer as the leading cancer killer of Canadian women by 1990. Given the relatively low survival rates for cancers caused by smoking and the lack of substantial improvement in rates for the most frequent types of cancer, preventive strategies that include effective measures to reduce tobacco consumption are urgently required.     

Cancer patterns in Canada.

Data from a cross-sectional survey of the health of Ontario children carried out in 1983 were used to provide estimates of the prevalence, patterns and sociodemographic correlates of the use of tobacco, alcohol and illicit drugs (substance use) among adolescents aged 12 to 16 years. Ninety-one percent of selected households participated. The prevalence rates of all categories of substance use, except use of inhalants, increased with increasing age. Among children aged 14 to 16 years the rates for girls were higher than those for boys for all categories of substance use except use of other, nondefined drugs. The prevalence rates of substance use tended to be higher in small urban areas except for use of marijuana (more prevalent in large urban areas) and use of inhalants (more prevalent in rural areas). The strongest evidence of clustering of substance use within families was found for smoking. Children who used less prevalent drugs (e.g., "hard" drugs) also tended to use the more prevalent ones (e.g., marijuana, tobacco and alcohol). Associations between substance use and low socioeconomic status suggested a positive relation with smoking and a negative relation with use of alcohol. The findings highlight the need for preventive programs aimed at specific subgroups in the adolescent population.