Biomedical subjects

Ricardo Ocaña-Riola

Publications and source records attributed to Ricardo Ocaña-Riola.

5 recordsLinked to original sources

PubMed2006

Rural habitat and risk of death in small areas of Southern Spain.

The purpose of this paper is to study the linkage between type of habitat and mortality from all causes in small areas of Southern Spain. An ecological study was conducted on 99,870 people who died between 1985 and 1999. The municipality was taken as the unit of analysis. Data analysis was carried out through hierarchical spatio-temporal bayesian models. Results show a 13.3% reduction in mortality rates among men and 14.1% among women in the most rural areas compared to more urban environments. The study demonstrates the usefulness of socio-demographic indices in small-area geographical analyses.

Bayes Theorem↗

PubMed2005

Non-homogeneous Markov processes for biomedical data analysis.

Some time ago, the Markov processes were introduced in biomedical sciences in order to study disease history events. Homogeneous and Non-homogeneous Markov processes are an important field of research into stochastic processes, especially when exact transition times are unknown and interval-censored observations are present in the analysis. Non-homogeneous Markov process should be used when the homogeneous assumption is too strong. However these sorts of models increase the complexity of the analysis and standard software is limited. In this paper, some methods for fitting non-homogeneous Markov models are reviewed and an algorithm is proposed for biomedical data analysis. The method has been applied to analyse breast cancer data. Specific software for this purpose has been implemented.

Algorithms↗

PubMed2004

Socio-economic level, farming activities and risk of cancer in small areas of Southern Spain.

An ecological design was used to study the relationship between cancer incidence and both socioeconomic and environmental features in Southern Spain. Twenty-four sites and 26,380 cases diagnosed in 1985--1996 were analysed. Generalised Additive Models were used for data analysis. Except for lip cancer, the urban areas showed an increase in cancer risk for all sites. The relative risks among urban and rural municipalities ranges between 1.09 for skin non-melanoma (95% CI: 1.00-1.18) and 1.64 for cervix cancer (95% CI: 1.28-2.12). The relative risk among areas with high and low unemployment was 1.29 for stomach cancer (95% CI: 1.07-1.57), 1.45 for oral cavity cancer (95% CI: 1.10-1.93) and 1.77 for oesophagus cancer (95% CI: 1.02-3.05). Areas with highest unemployment showed the lowest incidence of melanoma. Risk for leukaemia, gall bladder, breast and prostate cancer showed a significant decreases by approximately 28% in the municipalities with the highest illiteracy score. A high percentage of land under cultivation was related to uterine tumours, larynx, rectum, lung, skin non-melanoma and brain cancers. For these sites, the risk had a significant increase by between 23% (skin non-melanoma) and 70% (rectum). Areas with high intensive farming showed a significant increase in cancer risk for lip, oral cavity, larynx, oesophagus, colon, lung, and bladder cancer. The relative risks ranges between 1.16 for colon cancer (95% CI: 1.04-1.29) and 1.47 for oesophagus cancer (95% CI: 1.15-1.87). The results of this study reveal how important socio-economic and environmental factors are for the analysis of cancer incidence in small areas of Southern Spain.

Agriculture↗

PubMed2002

Variations in health services utilization by primary care patients.

This study analyses how both ambulatory care groups (ACGs) and physician characteristics explain the variability in health-service use among primary care patients in Spain. During the period 1996-1997, data derived from 52,152 patients and their 38 respective primary care physicians were collected. The response variables were as follows: number of visits; diagnostic tests requested; and referrals to a specialist. ACGs are an important variable that should be taken into account in order to explain health-service utilization. As for professionals, age and the post they hold are essential factors. Most of the unexplained variability is caused by patient characteristics.

Ambulatory Care↗

PubMedDate not supplied

[Research protocol for the mortality atlas of the provincial capitals of Andalusia and Catalonia (AMCAC Project)].

The aim of this work is to make known the multicentric project AMCAC, whose objective is to describe the geographical distribution of mortality from all causes in census groups of the provincial capitals of Andalusia and Catalonia during 1992-2002 and 1994-2000 respectively, and to study the relationship between the sociodemographic characteristics of the census groups and mortality. This is an ecological study in which the analytical unit is the census group. The data correspond to 298,731 individuals (152,913 men and 145,818 women) who died during the study periods in the towns of Almeria, Barcelona, Cadiz, Cordoba, Girona, Granada, Huelva, Jaen, Lleida, Malaga, Seville and Tarragona during the study periods. The dependent variable is the number of deaths observed per census group. The independent variables are the percentage of unemployment, illiteracy and manual workers. Estimation of the moderated relative risk and the study of the associations among the sociodemographic characteristics of the census groups and the mortality will be done for each town and each sex using the Besag-York-Mollie model. Dissemination of the results will help to improve and broaden knowledge about the population's health, and will provide an important starting point to establish the influence of contextual variables on the health of urban populations.

Algorithms↗