Small group estimation for public health.

We used synthetic estimation and linear regression to estimate the prevalence of selected risk factors and health status indicators in small populations. The derivation was based on the sociodemographic characteristics of the populations and the relationships between these variables and the health variables, as measured by the Ontario Health Survey (OHS). The estimates were validated by a comparison with the direct results of the OHS (gold standards). Synthetic estimates were much less dispersed than the regression estimates or the direct OHS estimates. Regression estimates performed better than synthetic estimates on most validation indicators, and combined approaches performed marginally better yet, although there were few clear patterns. Although correlation coefficients with gold standards in excess of 0.8 were obtained for some variables, the estimates rarely met pre-determined criteria for accuracy. At present these techniques have limited value for public health workers, but further work is justified, especially on approaches combining synthetic and regression estimation.

Health department administration of the Canadian Health Care Program.

Public administration of the Canadian health care program has been very successful in preserving a single-tiered system, ensuring accessibility and accountability, reducing administrative costs and the need for regulation, and fairly successful in achieving orderly planning and cost control. Although the provincial programs are administered by health departments, failure to link personal to public health services has robbed them of a population perspective, resulting in insufficient emphasis on prevention and on the effectiveness of interventions, and has hampered the development of comprehensive primary care. The program supports insufficient research and innovation, and has failed to link payments to performance. Four lessons for a national health care program are drawn from the Canadian experience: (1) keep it public; (2) use a single payer; (3) link personal health services to public health; and (4) provide health departments with policy expertise. Despite its overall success, the Canadian program can no longer be afforded. Many of the proposals for its reform challenge the values upon which the program is built.

Up-to-date denominators: evaluation of taxation family file for public health planning.

Public Health agencies need up-to-date population data, and Statistics Canada's Taxation Family File (T1FF) database, developed annually from T1 personal income tax forms, may meet this need. We compared 1989 T1FF data for Ottawa-Carleton with census data. The overall population estimate for the region was 98% of the census figure. Equivalent figures were 94% for central cities, 98% for suburbs and 122% for rural areas. The T1FF underestimated the population of children (89%) and seniors (93%). Population estimates for smaller neighbourhoods were poorer, some being wrong by a factor of more than two. The errors are probably due to postal code conversion. The T1FF provides fairly accurate estimates of the population of larger areas, and can be much more current than census data. It is less accurate for smaller areas, offers a limited range of variables, does not specify gender for children, and is fairly expensive. Health units with a major commitment to needs-based planning should consider using the T1FF for denominator data, despite its limitations.

Demand-side medical education: educating future physicians for Ontario.

Initiated by Associated Medical Services (AMS), Educating Future Physicians for Ontario is a 5-year collaborative project whose overall goal is to make medical education in Ontario more responsive to that province's evolving health needs. It is supported by AMS, the five universities with medical schools or academic health sciences centres and the Ontario Ministry of Health. The project's five objectives are to (a) define the health needs and expectations of the public as they relate to the training of physicians, (b) prepare the educators of future physicians, (c) assess medical students' competencies, (d) support related curricular innovations and (e) develop ongoing leadership in medical education. There are several distinctive features: a focus on "demand-side" considerations in the design of curricula, collaboration within a geopolitical jurisdiction (Ontario), implementation rather than recommendation, a systematic project-evaluation plan and agreement as to defined project outcomes, in particular the development of institutional mechanisms of curriculum renewal as health needs and expectations evolve.

Comparison of plasma exchange with plasma infusion in the treatment of thrombotic thrombocytopenic purpura. Canadian Apheresis Study Group.

BACKGROUND: Thrombotic thrombocytopenic purpura is an uncommon disease with a high mortality rate even with current treatment. The cause of the syndrome and its optimal treatment are unknown. Although both plasma exchange and plasma infusion have been useful treatments, it is not clear which is superior. In this report we describe a prospective randomized trial comparing plasma exchange with plasma infusion for the treatment of thrombotic thrombocytopenic purpura. METHODS: One hundred two patients with thrombotic thrombocytopenic purpura were randomly assigned to receive either plasma exchange or plasma infusion with fresh-frozen plasma on seven of the first nine days after entry into the trial. The total volume of plasma received by patients undergoing plasma exchange was three times that received by patients undergoing plasma infusion. All the patients also received aspirin and dipyridamole. The outcomes in the two groups were compared at the end of the first treatment cycle (day 9) and after six months. RESULTS: At the end of the first treatment cycle patients receiving plasma exchange had a higher rate of response as defined by an increase in the platelet count (24 of 51 patients) than those who received plasma infusion (13 of 51, P = 0.025). Of the 51 patients treated with plasma exchange, 2 died, whereas 8 of the 51 patients who received plasma infusion died (P = 0.035). After six months the outcome in the plasma-exchange group was still superior, with a response observed in 40 of 51 patients, whereas 25 of 51 patients in the plasma-infusion group responded (P = 0.002). Eleven patients in the plasma-exchange group died, as did 19 patients in the plasma-infusion group (P = 0.036). The overall mortality was 29 percent. CONCLUSIONS: Plasma exchange is more effective than plasma infusion in the treatment of thrombotic thrombocytopenic purpura.

The motor control assessment: an instrument to measure motor control in physically disabled children.

The Motor Control Assessment has been developed as a research tool for the assessment of motor skills in physically disabled children. In tests of concurrent validity it was found to be highly correlated with the results of the Physical Abilities Chart (Pearson coefficient = .96), and satisfactorily correlated with ranking of motor ability assigned using the clinical judgment of physiotherapists (Spearman rank coefficients = .63 to .97 in diagnostic subgroups). Estimates of both interrater and intrarater reliability were also high, with intraclass coefficients above .95.

Current trends in Canadian health care: disease prevention and health promotion.

The Canadian national health insurance plan has not extended to disease prevention in any comprehensive way, and to this extent is incomplete. The Task Force on the Periodic Health Examination has done outstanding work, but no provincial insurance plan has systematically adjusted the benefit schedule to reflect its recommendations. Thus, the place of disease prevention under the Canadian system of universal health insurance is remarkably similar to that in the United States. Health promotion has a somewhat different meaning in Canada from that in the United States, emphasizing intervention at the population level more than health education of individuals. The health promotion movement now enjoys considerable support in Canada, especially in the public health sector, in voluntary agencies, and in the policies of the federal and several provincial departments of health. The movement is almost completely separate from mainstream health services, and is unrelated to the insurance program. To date, there has been mostly talk, but several structures are in place which should lead to action.

Recruiting family physicians as participants in research.

Obtaining the voluntary participation of family physicians in quality of care research is a major problem in family practice research. An innovative approach was therefore required to recruit 120 randomly selected family physicians in southern Ontario in a quality of care study by the College of Family Physicians of Canada. A network of physician recruiters oriented to the study was organized for each district. This recruitment method resulted in an 84.5% participation rate. The relationship of these physician recruiters to the candidate and the method of approach were important factors in the enrolment process: the highest participation rate (95%) was obtained when the recruiters were friends of the candidate and when a personal meeting was arranged (91%). Recruiters were given an information package to help them in the recruitment process and rated the most useful items as follows: a policy statement about confidentiality, a description of the study and reprints of a published feasibility study. These results illustrate that cooperation in research in family physicians' offices can become a reality.

Quality of care in family practice: does residency training make a difference?

As the proportion of physicians who enter residency training in family practice steadily increases, so does the need to evaluate the impact of their training and postgraduate education on the quality of care in their practices. We audited the practices of 120 randomly selected family physicians in Ontario, who were separated into four groups: nonmembers of the College of Family Physicians of Canada (CFPC), members of the CFPC with no certification in family medicine, certificated members without residency training in family medicine and certificated members with residency training in family medicine. The practices were assessed according to predetermined criteria for charting, procedures in periodic health examination, quality of medical care and use of indicator drugs. Generally the scores were significantly higher for CFPC members with residency training in family medicine than for those in the other groups, nonmembers having the lowest scores. Patient questionnaires indicated no difference in satisfaction with specific aspects of care between the four groups. Self-selection into residency training and CFPC membership may account for some of the results; nevertheless, the findings support the contention that residency training in family medicine should be mandatory for family physicians.

Study of relation of continuing medical education to quality of family physicians' care.

A random sample of 120 physicians in Ontario was studied to assess quality of care in primary care and test an hypothesis that quality of care was related to continuing medical education (CME) activities. The quality-of-care scores were obtained by an in-office audit of a random selection of charts. The scores were global scores for charting, prevention, the use of 13 classes of drugs, and care of a two-year period for 182 different diagnoses. There were no relationships between global quality-of-care scores based on these randomly chosen charts and either the type or quantity of the physicians' CME activities. These activities were reading journals, attending rounds, attending scientific conferences, having informal consultations, using audio and video cassettes, and engaging in self-assessment. The implications of these findings are significant for future research in CME and for planners of present CME programs.

Cervical spinal cord stimulation for spasticity in cerebral palsy.

A prospective double-blind study of high cervical spinal cord stimulation conducted in eight moderately disabled, spastic, cerebral palsied children failed to demonstrate any significant improvement over base line function during chronic spinal cord stimulation at either optimal stimulation parameters or random placebo parameters. Chronic stimulation included 4 consecutive months of stimulation for 24 hours each day. Stimulators were randomly programmed at optimal parameters for 2 of the 4 months and at placebo parameters for the remaining 2 months. At the end of each month of chronic stimulation, subjects were assessed with a multidisciplinary test battery that included a self-assessment, specific clinical examinations, tests of gross and fine motor control, neuropsychological and neurophysiological tests, a detailed gait analysis, and video recordings. By 6 months after the completion of the study, only 1 of the 8 subjects continued to use his stimulator on a regular basis, with minimal benefit.

Estimating the combined effect of several disease precursors in health risk appraisal.

Health risk appraisal is an attractive health education technique but suffers from methodologic weaknesses. Many of the problems center on the formula that is usually used to estimate the combined effects of different disease precursors. The formula does not reflect current models of disease causation, underestimates the effects of protective factors, and confounds the effects of different precursors. We suggest a modification that resolves these problems by estimating the prevalence and associated composite relative risk for each combination of precursors before calculating the numerical estimate of combined risk. This method can be applied to the many diseases for which the data needed to support a multivariate approach are not available. We recommend its incorporation into existing appraisal instruments.

Mortality among Canadian military personnel exposed to low-dose radiation.

We carried out a cohort study of mortality among 954 Canadian military personnel exposed to low-dose ionizing radiation during nuclear reactor clean-up operations at Chalk River Nuclear Laboratories, Chalk River, Ont., and during observation of atomic test blasts in the United States and Australia in the 1950s. Two controls matched for age, service, rank and trade were selected for each exposed subject. Mortality among the exposed and control groups was ascertained by means of record linkage with the Canadian Mortality Data Base. Survival analysis with life-table techniques did not reveal any difference in overall mortality between the exposed and control groups. Analysis of cause-specific mortality showed similar mortality patterns in the two groups; there was no elevation in the exposed group in the frequency of death from leukemia or thyroid cancer, the causes of death most often associated with radiation exposure. Analysis of survival by recorded gamma radiation dose also did not show any effect of radiation dose on mortality. The findings are in agreement with the current scientific literature on the risk of death from exposure to low-dose radiation.

The satellite clinic: a model for the treatment of handicapped children in towns and rural areas.

A satellite clinic provided treatment for children living in a community 50 miles from an established Crippled Children's Treatment Centre. An evaluation of the service indicated that children attending the Satellite received more frequent treatment, at reduced costs to parents and social agencies. These children showed greater improvement in motor function than a control group, although no corresponding improvement in self-help skills was detected. Parents expressed a high level of satisfaction with the new service. The Satellite Clinic is recommended as a model for children unable to obtain regular treatment at an established centre.

Assessing the quality of care in family physicians' practices.

This feasibility study by the Practice Assessment Committee of the College of Family Physicians of Canada was conducted to define and produce instruments that could be used to assess quality of care rendered in family physicians' offices. The favorable response to these evaluations and the acceptance of the results indicates that this method can be useful to family physicians. The instruments identify family physicians' strengths and deficiencies so that with appropriate changes in the quality and efficiency of care, they are able to achieve higher levels of professional satisfaction. These methods may ultimately be used to establish acceptable standards for care given by family physicians in their offices.

Social work services in family practice.

The physician-social worker team in family practice offers potential benefits to both physician and patient. A demonstration of such attachments in Kingston, Ontario involved the equivalent of 3.5 fulltime social workers and 41 physicians. Social work services were provided to each participating physician for approximately half a day per week. Physicians used the service extensively, referring 630 patients over 24 months for a wide range of problems. Physicians evaluated the services favorably and the study shows social worker attachments to be feasible in the primary care setting.