[Principal components analysis]. / Análisis de componentes principales.

OBJECTIVE: This study wants to identify factors or components latent besides health indicators from Spanish regions, and its graphic output. DESIGN: Observational study. SETTING: Twenty eight indicators from regions were used: mortality, morbidity, communicable and no-communicable diseases, diet, dwelling and sanitary resources. Measurement was made between 1980-1988. INTERVENTIONS: Principal component analysis has been applied to the indicators, reducing data dimension. MEASUREMENT AND MAIN RESULTS: Eight factors have been extracted, which explain 90% of the original information. This analysis, as can be seen from communnalities, represents correctly the set of original variables. The factors with more easily interpretation were: shortage sanitary resources, develop diet, mortality, chronic diseases and accidental. CONCLUSIONS: Only reduction data dimension could be justify the use of principal component analysis. Behind the agrupation of variables is mostly the socioeconomic background.

[The hospital costs for patients with human immunodeficiency virus infection]. / Costes hospitalarios en pacientes con infección por el virus de la inmunodeficiencia humana.

BACKGROUND: The economic issues derived from the care of HIV patients are increasingly more important and they affect to different levels of sanitary assistance. In Spain these costs are not always evaluated and there is no information about the efficiency of inverted resources. METHODS: The cost of mean hospital stay due to HIV (+) patients has been estimated and compared with two infectious diseases: respiratory tuberculosis (TBC) and viral hepatitis (VH), and we have analyzed their evolution in the period studied. The study was conducted between July 1st 1987 and December 31st 1989 at the Infectious Unit for the three mentioned diseases. RESULTS: The 227 included patients originated 292 hospitalizations. The total cost derived from hospital stays was 169,466,323 ptas. The mean cost for HIV(+) patients was 576,184 ptas, for TBC patients 1,111,115 ptas, and for VH 443,219 ptas. The number of HIV(+) stays has increased each year. CONCLUSIONS: The observed results suggest that it could be interesting to think about new systems of inpatient care.