How markets evolve.

OBJECTIVE: To identify the factors affecting drug expenditure.Design. Cross-sectional study.Setting. Madrid Primary Care area. PARTICIPANTS: 21 health centres. MEASUREMENTS: Association of the drug expenditure per inhabitant of each health centre during 1999 with the characteristics of its staff and operation of the centre. MAIN RESULTS: Expenditure on drugs per inhabitant, 14360 plus minus 3040 pesetas (86.31 plus minus 18.27; general practitioners, 19.62 plus minus 23.8%; doctors working as locums, 40.48 plus minus 20.72%; women doctors, 59.76 plus minus 13.36%; family doctors, 38.57 plus minus 21.35%; team nurses, 86.6 plus minus 18.27%; population over 65, 18.03 plus minus 7.73%; patients per day attended by each general practitioner, 32.82 plus minus 3.81; number of sessions per year on prescription profiles, 5 plus minus 3.91; prescription avoidable because of health card: 3106 plus minus 808 pesetas (18.67 plus minus 4.86 ); compliance with service offer, 1.7 plus minus 3.78. Drug expenditure per inhabitant dropped when sessions on prescription profiles (p = 0.013), the percentage of women doctors (p = 0.067) and the percentage of family doctors (p = 0.035) increased; and it dropped too when the over-65 population (p = 0.099) and the amount of prescription avoidable through the card (p = 0.034) dropped. In the multivariate analysis, the sessions on prescription profiles (ss = -843), the percentage of nurses in the reformed model (ss = -155), the percentage of family doctors (ss = -142) and the percentage of doctors from the traditional model (ss = -121) explain 71.2% of the variability in drug expenditure per inhabitant (F = 6.909; p = 0.002). CONCLUSIONS: The sessions to discuss prescription profiles, the presence of nurses from the reform model, postgraduate medical training and the employment of doctors under the traditional model are the factors that our study finds are linked to lower drug expenditure per inhabitant.

Catchment Area, Health↗

PubMed2002

Dynamics of change in local physician supply: an ecological perspective.

The purpose of this study is to employ an ecological framework to identify factors that have an impact on change in local physician supply within the USA. A particular specialty type of patient care physicians in a local market is defined as a physician population. Four physician populations are identified: generalists, medical specialists, surgical specialists, and hospital-based specialists. Based on population ecology theory, the proposed framework explains the growth of a particular physician population by four mechanisms: the intrinsic properties of this physician population; the local market's carrying capacity, which is determined by three environmental dimensions (munificence, concentration, diversity); competition within the same physician population; and interdependence between different physician populations. Data at the level of Metropolitan Statistical Areas (MSAs) were compiled from the US Area Resources File, the American Hospital Association Annual Surveys of Hospitals, the American Medical Association Census of Medical Groups, the InterStudy National HMO Census, and the US County Business Patterns. Changes in the number and percentage of physicians in a particular specialty population from 1985 to 1994 were regressed, respectively, on 1985-94 changes in the explanatory variables as well as their levels in 1985. The results indicate that the population ecology framework is useful in explaining dynamics of change in the local physician workforce. Variables measuring the three environmental dimensions were found to have significant, and in some cases, differential effects on change in the size of different specialty populations. For example, both hospital consolidation and managed care penetration showed significant positive eflects on growth of the generalist population but suppressing effects on growth of the specialist population. The percentage of physicians in a particular specialty population in 1985 was negatively related to change in the size of that specialty population between 1985 and 1994, suggesting the existence of competition. Overall, the findings of this study facilitate a better understanding of the complexity of physician workforce supply.

Catchment Area, Health↗