Robin Haynes

Car travel time and accessibility by bus to general practitioner services: a study using patient registers and GIS.

Accessibility to general practitioner (GP) surgeries was investigated in a population study of East Anglia (Cambridgeshire, Norfolk and Suffolk) in the United Kingdom. Information from patient registers was combined with details of general practitioner surgery locations, road network characteristics, bus routes and community transport services, and a geographical information system (GIS) was used to calculate measures of accessibility to surgeries by public and private transport. Outcome measures included car travel times and indicators of the extent to which bus services could be used to visit GP surgeries. These variables were aggregated for wards or parishes and then compared with socio-economic characteristics of the populations living in those areas. The results indicated that only 10% of residents faced a car journey of more than 10 min to a GP. Some 13% of the population could not reach general medical services by daily bus. For 5% of the population, the car journey to the nearest surgery was longer than 10 min and there was no suitable bus service each weekday. In the remoter rural parishes, the lowest levels of personal mobility and the highest health needs indicators were found in the places with no daytime bus service each weekday and no community transport. The overall extent of accessibility problems and the existence of inverse care law effects in some rural localities have implications for the NHS, which aims to provide an equitable service to people wherever they live. The research also demonstrates the potential of patient registers and GIS as research and planning tools, though the practical difficulties of using these data sources and techniques should not be underestimated.

Household and neighbourhood risks for injury to 5-14 year old children

Injuries in childhood are strongly related to poverty at the household level and to living in a deprived neighbourhood, but it is not clear whether these effects are independent. In this prospective population study, all injuries to 5-14 year old children living in the city of Norwich, UK, and presented at the hospital Accident and Emergency Department over a 13 month period were recorded (N=3526). Information on the population of resident children and household composition was assembled from the health authority population register. Neighbourhood information was extracted from the census and local surveys. Unadjusted risks were calculated for individual and neighbourhood factors, followed by multilevel modelling in which predictors were included at three levels: individual, enumeration district and social area (neighbourhood). The overall injury rate was 16.44 per 100 children per year. Injury rates between neighbourhoods varied two-fold and were highest in more deprived areas. In the final multilevel model injury risk was related to gender (boys vs. girls OR=1.35), age of child (OR=1.07 per year), number of adults in the household (OR=0.91 per adult), and age gap between child and eldest female (15-24 years vs. 25-34 years, OR=1.15). Injury rates were also related to social area deprivation, although variations in injury rates between neighbourhoods were not wholly explained by deprivation. The adjusted odds ratio between the most and least deprived social areas was 1.35. Excluding less serious injuries did not substantially change the results. The risks were very similar to those found in a previous study of pre-school children, with the same neighbourhoods identified as high and low risk as before. This evidence that neighbourhood factors independently influence injury risk over and above individual and household factors supports the use of area-based policies to reduce injuries in children.

Travel time to hospital and treatment for breast, colon, rectum, lung, ovary and prostate cancer.

The aim was to examine the effect of geographical access to treatment services on cancer treatment patterns. Records for patients in northern England with breast, colon, rectal, lung, ovary and prostate tumours were augmented with estimates of travel time to the nearest hospital providing surgery, chemotherapy or radiotherapy. Using logistic regression to adjust for age, sex, tumour stage, selected tumour pathology characteristics and deprivation of place of residence, the likelihood of receiving radiotherapy was reduced for all sites studied with increasing travel time to the nearest radiotherapy hospital. Lung cancer patients living further from a thoracic surgery hospital were less likely to receive surgery, and both lung cancer and rectal cancer patients were less likely to receive chemotherapy if they lived distant from these services. Services provided in only a few specialised centres, involving longer than average patient journeys, all showed an inverse association between travel time and treatment take-up.

Inequalities in health and health service use: Evidence from the general household survey

The General Household Survey data file for 1982 was examined to identify variations in self-reported morbidity and health service use between socio-economic groups and geographical areas in Great Britain. Both acute and chronic morbidity varied with socio-economic status. Morbidity was more strongly related to housing tenure and car availability than to occupational class. A north-west to south-east gradient in sickness was observed, although morbidity was comparatively high in Wales and comparatively low in Scotland, taking mortality differences into account. The highest age-adjusted morbidity ratios were for females in multiple occupancy inner city areas. Service use rates in relation to reported sickness showed little systematic variation. There was an indication that lack of car transport was an inhibiting factor for the sick in rural areas.

Deprivation and poor health in rural areas: Inequalities hidden by averages

Poor health and social deprivation scores in 570 wards in East Anglia, UK, were much less associated in rural than in urban areas. The deprivation measure most closely related to poor health in the least accessible rural wards was male unemployment, but use of this measure did not remove the urban-rural gradient of association strength. Neither did replacing wards by smaller enumeration districts as the units of analysis. The differences between urban and rural correlations were removed by restricting the comparison to wards with the same unemployment range and combining pairs of rural wards with similar deprivation values. Apparent differences between rural and urban associations are therefore not due to the choice of deprivation indices or census areas but are artifacts of the greater internal variability, smaller average deprivation range and smaller population size of rural small areas. Deprived people with poor health in rural areas are hidden by favourable averages of health and deprivation measures and do not benefit from resource allocations based on area values.

Potential Accessibility, Travel Time, and Consumer Choice: Geographical Variations in General Medical Practice Registrations in Eastern England

The availability of choice is a neglected aspect in studies of geographical accessibility, which typically concentrate on distance to the nearest service. Records of patient registrations with general medical practices offer the opportunity to examine the geographical distribution of choice for an essential service. This population study of two million residents of Cambridgeshire, Norfolk, and Suffolk used postcodes extracted from patient registers and estimated car travel times from residential locations to general practice surgeries in a geographic information system. Only 56% of the population were registered with the practice nearest their home. People were more likely to use the nearest practice if they lived in rural rather than urban areas and where a surgery was within walking distance. Choice, as measured by the number of practices used by 95% of residents, was highest in the larger urban areas and lowest in small towns and rural areas with a local surgery. Ten percent of the population were served by monopoly practices. Overall, the distribution of registrations reflected a regular and predictable substitution of choice for increased travel time. People were 29% less likely to register with a practice for every additional minute of travel time: an almost perfect distance-decay relationship that was used to calibrate a potential model of accessibility over the study area. The resulting values of potential accessibility were found to approximate the combination of travel time to the nearest surgery and the actual range of choice exercised by residents. This demonstration that the potential accessibility model reflects consumer behaviour has applications beyond the health field.

Limiting long term illness and its associations with mortality and indicators of social deprivation

STUDY OBJECTIVE--To examine geographical variation in limiting long-term illness in England and Wales and assesses the extent of its similarity with the distribution of mortality rates and of deprivation. DESIGN--A geographically based study using data from the 1991 census on limiting long term illness. Maps and regression analysis are used to compare the distribution of standardised illness ratios with standardised mortality ratios and indicators of social deprivation. SETTING--A total of 401 local authority districts in England and Wales. PARTICIPANTS--The population of England and Wales enumerated in the 1991 census. MAIN RESULTS--The geographical pattern of limiting long term illness shows many similarities with that of mortality but there are also some differences. Both are positively associated with indicators of social deprivation, with limiting long term illness tending to show stronger correlations, particularly in the elderly. Most of Wales and many industrial areas of northern England have higher rates of long term illness than would be expected from their mortality rates, while much of south eastern England has lower than expected rates. CONCLUSIONS--Moves towards using data on limiting long term illness instead of standardised mortality rates would have important implications for NHS resource allocations. Further assessment of the reliability of these data on self reported morbidity is required. in particular, there is a need to assess how much they reflect real differences in ill health rather than the influence of socioeconomic or cultural factors affecting the likelihood of a positive answer to the census question on limiting long term illness.

The effects of accessibility on general practitioner consultations, out-patient attendances and in-patient admissions in Norfolk, England

A social survey was conducted to investigate the effects of accessibility on contacts with general practitioners and hospitals under the National Health Service in the predominantly rural county of Norfolk. Random samples of adults were taken close to hospital and general practitioner services in the city of Norwich, in villages close to Norwich with and without a general practitioner surgery and in villages relatively remote from the city with and without a surgery. General practitioner consultation rates, out-patient attendance rates and in-patient admissions were all found to decline with decreasing accessibility. For people with a long-standing illness, the main difference in rates was between urban and rural areas. The groups most affected in the rural areas were those with the highest relative need of health care. Their counterparts in the city used the health services much more. For the larger section of the sample, those with no long-standing illness, the most significant differences were between the various rural locations. Here, both distance to a surgery and distance to the city hospitals were associated with decreasing consultation, out-patient and in-patient rates. The main trend was of young mobile people with high expectations in places with readily accessible health services using those services more than would be expected from their usage rates elsewhere. There was also evidence among the people with no long-standing illness of less prosperous sub-groups being affected by remoteness at the out-patient stage.

District variations in road curvature in England and Wales and their association with road-traffic crashes

Bends in roads are known to cause road-traffic crashes, but do areas with many road bends have more collisions than areas with straighter roads? A geographical information system was used to generate indicators of average road curvature from a road-network dataset of England and Wales at the local-authority district level. The indicators were the number of bends per kilometre, the ratio of road distance to straight distance, the proportion of road lengths that were straight, the cumulative angle turned per kilometre and the mean angle of each bend. Generally the five measures were associated. Road curvature was highest on minor roads and least on major roads, and metropolitan districts had straighter road networks than nonmetropolitan districts. Counts of the number of road-traffic crashes resulting in fatalities, serious injuries, and slight injuries in each district were obtained from police ‘Stats 19’ records. The association between each of the curvature measures and the number of fatal, serious, and slight collisions in each district was determined by negative binomial regression analysis. Collision numbers were negatively related to road curvature after adjusting for other risk factors, so districts with straighter roads had more crashes. The cumulative angle was the curvature measure most strongly related to fatal road crashes. An increase of 1° per km was associated with approximately a 0.5% reduction in crashes, enough to explain more than a two fold difference in collision rates over the range of the data. Separate analysis of crashes on major roads, ‘B’ class roads, and minor roads confirmed the conclusion. Although individual road bends may be hazardous, these results suggest that road curvature at the district scale is protective.

Mortality, long-term illness and deprivation in rural and metropolitan wards of England and Wales

The relationships between mortality, limiting long-term illness and indicators of social deprivation were investigated using regression analysis on data for rural wards, metropolitan wards and the remaining wards in England and Wales. Regional differences were controlled. In rural wards, people had better health than average and slightly better health than would be expected from their deprivation scores. Average levels of health in rural areas were only weakly related to deprivation, which was partly but not fully due to the restricted range of average deprivation values in rural wards. In metropolitan areas, relatively poor levels of health were largely explained by social deprivation, but people in Inner London were healthier than might be expected from measures of deprivation. The relationship between health and social deprivation is therefore not uniform over England and Wales, but varies between geographical types of area. One consequence is that resource allocation on the basis of social deprivation would put the populations of rural areas and Inner London at an advantage.