Table 4.

The methodological approaches established during the first phase of research

Methodology	Description	Assumptions	Advantages	Limitations	Overcoming limitations	Requirements	Documented usagea
Supply
Training	Projects the availability of health-care professionals based on the current stock of clinicians, the training process (entries and dropouts), migration flows, attritions and retirement rates	Demand for medical services is assumed to remain constant and the projections are used to reduce the supply gap	Predictions for the future supply can be obtained in a fairly simple and immediate way	Demand for medical services is assumed to remain constant, which may not be true No critical assessment of the adequacy of current service levels	Incorporate a model of demand: economic or needs-based (or both)Evaluate current level of service through waiting lists, overtime hours,foreign workers, etc.	Accurate and up-to-date accounting of the current stock of physicians and nurses, migration rates, entry and drop out rates and expected retireesService usage levels from the health-care sector	Australia, Belgium,Canada, Chile,Denmark, Finland,France, Germany,Ireland, Israel, Japan,South Korea,Norway, Switzerla nd,The Netherlands,United Kingdom,USA
Productivity	Reorganize services and/or economic incentives to promote higher productivity. Work harder or work smarter	Physicians and nurses act as rational agentsan d react to economic incentives like wage increases	Does not require a change in the quantity of human resources. Can be implementedimmediately	Productivity improvements may not be enough to accommodate large gaps in the supply of professionals	Do not preclude from evaluating the number of professiona ls necessary given differentproductivity levels	Operational indicators like the number of patients served with a given number of FTEs (or head counts)	Australia, Canada,Japan, Korea, Netherlands, N orway,Switzerland, UnitedKingdom, USA
Skill mix	Delegate certain tasks to other health professionals. Substitution can be horizontal (betweenmedical professions) orvertical (betweenphysicians and nurses)	Professionals can assume new roles and perform new tasks	Does not require a change in the quantity of human resources. Can be implemented immediately	Enforcing such changes can be a political challange.Does not solve large gaps in the supply	Providing success stories to involved stakeholders, healthauthorities and medical associations	Education schools that can provide advanc ed education to the existing workforce	Netherlands, United Kingdom
Worker-to-population ratios	Specifies desirable worker-to-population ratios based on direct comparison with another region of country	Regions and/or countries can be directly compared	Extremely easy to understand and apply Useful forproviding baseline comparisons	Does not take into account the intrinsic differences between regions a nd countries, the productivity and s kill mix of the avail able workforce	Does not take into account the intrinsic differences between regions and countries, the productivity and skill mix of the available workforce	Records of the current workforce to population ratios	Chile, France, Ireland, Israel, Switzerland,United Kingdom
Demand
Economic	Estimates future requirements by projecting the effect of demographic and socio-economic factors on the current level of service	Current level of service is adequate.Skill mix and distribution of health service is appropriateDemographic profile of the population and its effect on health-care demand can be accurately forecasted	Conceptually easy to understand and to apply Allows decoupling of the various components of demand and their influence on the overall aggregate demand	Tends to produce estimates of HHR demand that exceed practical limits No criticalassessment of the adequacy of current service levels Ignores the real demand,focusing instead onthe effective demand	Take financial constraints into considerationEvaluate current level of service through waiting lists, overtime hours, foreign workers, etc.Include a needs-basedevaluation	Accurate and long-term demographic estimates Service-usage levels from the health-care sector Macroeconomic indicators and stati stical data crossing income and usage	Australia, Belgium, Canada, Denmark, Finland, Germany, Japan, Norway, South Korea, Switzerland, The Netherlands, USA
Needs	Considers the effect of epidemiology on the demand for health-care services Projects age- and gender-specific needs based on morbidity epidemiological trends	All health-care needs can and should be metResources are used in accordance to needs	Allows for a fine-gra inedanalysis of the requirements of each medical specialty Is independent of the current service-utilization ratios Easy to understand	Absence of ec onomic/efficiency considerations mayren der the projections unattainable Dependent on epidemiological projections which may not be obviousDoes not consider the current level of provision nor the capacity of the country to deliver health care	Consider an upper bound for a practical resultConsider projections of the most common he alth patterns Incorporate econo mic considerations in the model	Demographic esti mates that are accurate Service-usage levels from the health-care sector	Belgium, Canada, Germany, United Kingdom
Service targets	Defines normative targets for the production of health-care services, which are then converted to HHR requirements	Assumes that established service targets are achievable in terms of financial and physical capital resources	Easy to d efine, interpret and understandFacilitates cost estimation Requires modest data and planning capabilities	May originate unrea listic assumptionsIgnores financial and other active constraints	Incorporate economic considerations in the model	Current level of service

^aOECD Report

Source: adapted from Hall and Mejia [13], O’Brien-Pallas [11] and Dreesch [1]