Is geographical distance a barrier in the use of public primary health services among rural and urban young adults? Experience from Northern Finland

OBJECTIVES

To study the role of distance in public primary health service use in rural and urban local residential areas (1 km² grids) among the young adults of the Northern Finland Birth Cohort 1966 (N = 4503).

STUDY DESIGN

Cross-sectional study of a cohort born in Northern Finland in 1966.

METHODS

Use of local health centres was surveyed by postal questionnaire in 1997, and distance from study subjects' home to health centre was calculated along road network. The crude and adjusted incidence rate ratios (IRR) and their 95% confidence intervals were calculated for distance, predisposing and illness-level variables. Distance-related health inequity indices were calculated.

RESULTS

The IRRs indicated 1.5-fold higher rate of health centre visits among subjects living farther than 10 km compared to subjects living within 2 km from health centre in urban areas. In rural areas, IRRs indicated no significant association with distance and health centre use. No distance-related inequity in the use of health centre services was found.

CONCLUSIONS

Distance does not seem to be major barrier in health service use among these 31-year old adults. However, closer study of some groups, such as the rural unemployed, might be valuable.

Small-area variation in mortality in the city of Oulu, Finland, during the period 1978--1995

The aim of the present work was to explore small-area differences in mortality from all causes among males and females within the city of Oulu during the period 1978--1995 and to identify areas where mortality has been persistently high or low. Analyses carried out using Geographical Information System techniques with geo-referenced mortality data produced at a resolution of 1 x 1 km showed significant regional variations in mortality within the city. The differences were wide enough to suggest variations of several years in longevity, and were probably indicative of marked variations in the incidences of diseases. Observed mortality differences may reflect the influence of the rapidly changing urban structure and consequent health effects based on selection, lifestyles, work exposures and deprivation.

Regional differences in the incidence of insulin-dependent diabetes mellitus among children in Finland from 1987 to 1991. Childhood Diabetes in Finland (DiMe) Study Group

The regional pattern of insulin-dependent diabetes mellitus (IDDM) incidence among children in Finland was analysed applying several methods attempting to describe the geographical variation in occurrence of IDDM. From 1987 to 1991 the number of newly diagnosed cases aged 14 years or less at diagnosis was 1728. The incidence, the incidence rate ratio and the Bayes relative risk (RR) for IDDM were calculated by municipality, by functional area (an urban centre with a subordinated surrounding area) and by area with a population of equal size at risk employing the Geographical Information Systems. The association of IDDM incidence with the degree of urbanization was assessed using the population density as a criterion for the degree of urbanization. The overall mean of the IDDM incidence was 35 per 100000 persons per year. Between municipalities the incidence varied from 4 to 245 per 100000 persons per year, whereas a clear regional pattern was seen among the functional areas and the incidence varied from 26 to 43 per 100000 persons per year. The RR for IDDM among the municipalities ranged from 0.82 to 1.34 and from 0.73 to 1.27 among the functional areas. The incidence determined in four zones with the same size of population was the highest in the middle part of the country. There was a strong inverse correlation between population density and the incidence of IDDM and this also applied to the relationship between child population density and incidence.

Detection of overall space-time clustering in a non-uniformly distributed population. DiMe Study Group

We developed a test statistic based on an approach of Whittemore et al. (1987) to detect space-time clustering for non-infectious diseases. We extended the spatial test of Whittemore et al. by deriving conditional probabilities for Poisson distributed random variables. To combine spatial and time distances we defined a distance matrix D, where dij is the distance between the ith and jth cell in a three-dimensional space-time grid. Spatial and temporal components are controlled by a weight. By altering the weight, both marginal tests and the intermediate test can be reached. Allowing a continuum from a pure spatial to a pure temporal test, the best result will be gained by trying different weights, because the occurrence of a disease might show some temporal and some spatial tendency to cluster. We examined the behaviour of the test statistic by simulating different distributions for cases and the population. The test was applied to the incidence data of insulin-dependent diabetes mellitus in Finland. This test could be used in the analysis of data which are localized according to map co-ordinates, by addresses or postcodes. This information is important when using the Geographical Information System (GIS) technology to compute the pairwise distances needed for the proposed test.