The physician shortage in Canada is multifactorial. It is important to identify potential factors and policies contributing to the problem. An extensive literature review to retrieve primary source articles was performed using the PubMed database. Other sources of information included reports identified using the websites of organizations, associations, government bodies and Google scholar, as well as additional primary source articles identified using reference lists of retrieved articles and reports. Healthcare policy changes in the 1990’s limited the growth of physician supply through the reduction of medical school enrolment, restrictions on recruitment of international medical graduates into the workforce, redistribution of family physician and specialist mix and loss of physicians to the US. Inadequate supply of primary care physicians is reflected in the low interest among medical students in a family medicine career and the shortage of physicians in rural areas. Reduction of physician productivity is characterized by an aging physician population, greater proportion of women in the workforce and the reduction of direct patient care hours among the new generation of physicians. The problem is further exacerbated by inefficiencies in healthcare expenditures, judging from high healthcare spending and low physician-to-population ratio. An understanding of factors contributing to the physician shortage is essential in order to develop successful strategies to alleviate inadequate physician supply.

A formulation of the traveling salesman problem with more than one salesman is offered. The particular formulation has computational advantages over other formulations. Experience is obtained with an exact branch and bound algorithm employing both upper and lower bounds (mean run time for 55 city problems is one minute). Due to the special formulation, certain subtours may satisfy the constraints, thus reducing the search. A very good initial tour and upper bound are employed. The determination of these as well as the pathology of the formulation and the algorithm are discussed. No increase in computation time over the one-salesman case is experienced.

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Clinical research and educational research face similar practical and ethical constraints that impact the rigor of both kinds of studies. Practical constraints facing undergraduate science education research include small sample sizes (largely a result of disproportionate incentives to conduct educational research at small colleges versus large universities), and the impossibility of randomizing individual students to separate arms of a study. Ethical constraints include gaining the informed consent and assuring the confidentiality of study participants, and the requirement of equipoise (i.e., that it is unethical to subject some study participants to an experimental treatment that researchers have good reason to believe to be inferior to another treatment). While these constraints have long been recognized for clinical research, their implications for educational research have not been fully recognized. Criticism that educational research lacks rigor should be tempered by the recognition that educational research is not parallel to laboratory research, but is parallel to clinical research. These parallels suggest solutions to some of the practical and ethical difficulties faced by educational researchers, as well.