[What epidemiologic goals in psychiatry for public statistics?].
BACKGROUND
French public statistics to be used in psychiatry are currently being reorganized. The Academy of Sciences and professionals have stated that epidemiologists should be involved when large databases are being designed.


METHODS
The three parts of the current French public statistics system are described: routine data, comprehensive census surveys and surveys with representative samples. Epidemiologic goals for public statistics are analysed according to two lines: the study of inequalities of access to care as well as during care and the study of populations in care. Some consequences on the way indicators are used are discussed.


RESULTS
The importance of the question of access to care in psychiatry is known since the epidemiologic catchment area research. Although inequalities of access to psychiatric care are an important research field, few studies are related to them in France. They should be studied in France all the more since public psychiatry is sectorised since 1960 in order to provide continuity of care. Models can be used to that end, most notably the two books about the pathway to care by Golberg and Huxley, as well as the mental health matrix by Thornicroft and Tansella. The internal dynamics of populations in psychiatric care are closely related to the preceding questions; several examples of possible researches are given. However, since populations in care are constructed, their construction process must be analysed, lest comparisons between populations be biased. Three factors help describe this process: the relations with neighbouring populations, the propensity to enter the population in care and the perimeter of the population in care. Consequences on the use of indicators are discussed in relation to three examples: prevalence, length of care and rehospitalisation rates.


CONCLUSIONS
It is important to organize a consistent information system about psychiatric care, based upon a thorough problem analysis. The issues at stake and the results to be expected go beyond the sole psychiatric domain.
Chapireau
F
F
Institut national d'études démographiques, MSE, 133, boulevard Davout, 75980 Paris cedex 20, France. francois.chapireau@ined.fr
D000328:Adult; D005602:France / Q000453:epidemiology; D019538:Health Care Surveys; D006297:Health Services Accessibility; D006306:Health Surveys; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D001523:Mental Disorders / Q000453:epidemiology* / Q000628:therapy*; D008605:Mental Health Services / Q000706:statistics & numerical data; D010359:Patient Readmission; D015995:Prevalence; D011570:Psychiatry / Q000592:standards / Q000706:statistics & numerical data*; D011634:Public Health; D011787:Quality of Health Care