Deprivation payments to general practitioners: limitations of census data.

The census data from which deprivation payments have been calculated since June 1995 suffer from limitations including underenumeration; under counting of homeless people and refugees, and artefactual errors because of the way in which the 1991 census data were tabulated. These limitations reduced the fairness of the changes that many practices experienced in their deprivation payments. The validity of the current system of deprivation payments would be improved if these limitations were borne in mind when allocating payments to practices and if enumeration districts were used as the basis of payments rather than electoral wards.

Home visiting by general practitioners in England and Wales.

OBJECTIVE: To use data from the fourth national survey of morbidity in general practice to investigate the association between home visiting rates and patients' characteristics. DESIGN: Survey of diagnostic data on all home visits by general practitioners. SETTING: 60 general practices in England and Wales. SUBJECTS: 502 493 patients visited at home between September 1991 and August 1992. MAIN OUTCOME MEASURES: Home visiting rates per 1000 patient years and home visiting ratios standardised for age and sex. RESULTS: 10.1% (139 801/1 378 510) of contacts with general practitioners took place in patients' homes. The average annual home visiting rate was 299/1000 patient years. Rates showed a J shaped relation with age and were lowest in people aged 16-24 years (103/1000) and highest in people aged > or = 85 years (3009/1000). 1.3% of patients were visited five or more times and received 39% of visits. Age and sex standardised home visiting ratios increased from 69 (95% confidence interval 68 to 70) in social class I to 129 (128 to 130) in social class V. The commonest diagnostic group was diseases of the respiratory system. In older age groups, diseases of the circulatory system was also a common diagnostic group. Standardised home visiting ratios for the 60 practices in the study varied nearly eightfold, from 28 to 218 (interquartile range 67 to 126). CONCLUSIONS: Home visits remain an important component of general practitioners' workload. As well as the strong associations between home visiting rates and patient characteristics, there were also large differences between practices in home visiting rates. A small number of patients received a disproportionately high number of home visits. Further investigation of patients with high home visiting rates may help to explain the large differences in workload between general practices and help in allocation of resources to practices.

Age and sex differences in the management of ischaemic heart disease.

OBJECTIVE: To investigate age and sex differences in the utilisation of hospital services for ischaemic heart disease. DESIGN: Analysis of routine mortality data and hospital activity data. SETTING: South West Thames Regional Health Authority. SUBJECTS: Residents of the South West Thames Regional Health Authority who in 1991 either died from ischaemic heart disease or were admitted to an NHS hospital in England and Wales with a main diagnosis of ischaemic heart disease. MAIN OUTCOME MEASURES: Ratio of consultant episodes to deaths from ischaemic heart disease (as a proxy measure of the utilisation of hospital care), and the percentages of consultant episodes in which further investigation (angiography or catheterisation) or revascularisation treatment (coronary artery bypass grafting or angioplasty) were carried out. RESULTS: The ratio of episodes to deaths was similar in men and women (odds ratio for men vs. women 0.96, 95% confidence intervals 0.90 to 1.03). The percentage of episodes in which further investigation was carried out was higher in men than women (odds ratio for men vs. women 1.46, 95% confidence intervals 1.25 to 1.70) as was the percentage of episodes in which revascularisation treatment was carried out (odds ratio for men vs. women 1.46, 95% confidence intervals 1.20 to 1.77). The ratio of episodes to deaths, the percentage of episodes in which further investigation was carried out, and the percentage of episodes in which revascularisation treatment was carried out all declined with age (all p values < 0.001). CONCLUSIONS: Women with ischaemic heart disease are as likely as men to be admitted to hospital, but after admission are less likely to undergo further investigation and revascularisation treatment. Elderly patients with ischaemic heart disease are less likely than younger patients to be admitted to hospital; after admission, they are also less likely to undergo further investigation and revascularisation treatment. Further research is needed to determine whether these age and sex differences in the use of hospital services are clinically justified.

Annual night visiting rates in 129 general practices in one family health services authority: association with patient and general practice characteristics.

BACKGROUND: Rates of night visiting by general practitioners have increased steadily over the last 30 years and vary widely between general practices. AIM: An ecological study was carried out to examine night visiting rates by general practices in one family health services authority, and to determine the extent to which differences in night visiting rates between practices could be explained by patient and practice characteristics. METHOD: The study examined the variation in annual night visiting rates, based on night visit fees claimed between April 1993 and March 1994, among 129 general practices in Merton, Sutton and Wandsworth Family Health Services Authority, London. RESULTS: Practices' annual night visiting rates varied from three per 1000 to 75 per 1000 patients. The percentages of the practice population aged under five years and aged five to 14 years were both positively correlated with night visiting rates (r = 0.38 and r = 0.35, respectively), as were variables associated with social deprivation such as the estimated percentage of the practice population living in one-parent households (r = 0.24) and in households where the head of household was classified as unskilled (r = 0.20). The percentage of the practice population reporting chronic illness was also positively associated with night visiting rates (r = 0.26). The percentages of the practice population aged 35 to 44 years and 45 to 54 years were both negatively associated with night visiting rates (r = -0.34 and r = -0.31, respectively) as was the estimated list inflation for a practice (r = -0.31). There was no significant correlation between night visiting rates and the distance of the main practice surgery from the nearest hospital accident and emergency department. There was also no association between night visiting rates and permission to use a deputizing service. In a stepwise multiple regression model, the multiple correlation coefficient was 0.56 with four factors (percentage of the practice population aged under five years, percentage aged 35-44 years, percentage who were chronically ill and estimated list inflation) explaining 32% of the variation in night visiting rates. CONCLUSION: Only about one third of the variation in night visiting rates between practices could be explained by patient and practice variables derived from routine data. Population-based research using data collected on individual patients and practices is required to improve current understanding of the patient and practice characteristics that influence the demand for night visits and of why night visiting rates vary so widely between practices.

Using data from the 1991 census.

The 1991 census for England and Wales provides a substantial amount of data on demography, ethnicity, housing tenure, employment status, and other social factors for geographical areas ranging in size from enumeration districts upwards. Many in the health service and in the academic community are making use of the data in the 1991 census. However, users of census data need to be aware of the problems and limitations of these data, which include the format of the data, data modification and suppression, sampling error, and underenumeration. An important innovation of the 1991 census was that the census form included a question on the postcode of respondents; this allowed the Office of Population Censuses and Surveys to produce a postcode-enumeration district look up table which overcomes many of the problems previously encountered in trying to assign postcodes to enumeration districts. The new look up table also includes the grid reference of postcodes, and this will improve the geographical referencing of census data.

Do general practitioners influence the uptake of breast cancer screening?

OBJECTIVES: To investigate the relative importance of patient and general practice characteristics in explaining variations between practices in the uptake of breast cancer screening. DESIGN: Ecological study examining variations in breast cancer screening rates among 131 general practices using routine data. SETTING: Merton, Sutton, and Wandsworth Family Health Services Authority, which covers parts of inner and outer London. MAIN OUTCOME MEASURE: Percentage of eligible women aged 50-64 who attended for mammography during the first round of screening for breast cancer (1991-1994). RESULTS: Of the 43,063 women eligible for breast cancer screening, 25,826 (60%) attended for a mammogram. Breast cancer screening rates in individual practices varied from 12.5% to 84.5%. The estimated percentage list inflation for the practices was the variable most highly correlated with screening rates (r = -0.69). There were also strong negative correlations between screening rates and variables associated with social deprivation, such as the estimated percentage of the practice population living in households without a car (r = -0.61), and with variables that measured the ethnic make-up of practice populations, such as the estimated percentage of people in non-white ethnic groups (r = -0.60). Screening rates were significantly higher in practices with a computer than in those without (59.5% v 53.9%, difference 5.6%, 95% confidence interval 1.1 to 10.2%). There was no significant difference in screening rates between practices with and without a female partner; with and without a practice nurse; and with and without a practice manager. In a forward stepwise multiple regression model that explained 58% of the variation in breast cancer screening rates, four factors were significant independent predictors (at P = 0.05) of screening rates: list inflation and people living in households without a car were both negative predictors of screening rates, and chronic illness and the number of partners in a practice were both positive predictors of screening rates. The practice with the highest screening rate (84.5%) contacted all women invited for screening to encourage them to attend for their mammogram and achieved a rate 38% higher than predicted from the regression model. Breast cancer screening rates were on average lower than cervical cancer screening rates (mean difference 14.5%, standard deviation 12.0%) and were less strongly associated with practice characteristics. CONCLUSIONS: The strong negative correlation between breast cancer screening rates and list inflation shows the importance of accurate age-sex registers in achieving high breast cancer screening rates. Breast cancer screening units, family health services authorities, and general practitioners need to collaborate to improve the accuracy of the age-sex registers used to generate invitations for breast cancer screening. The success of the practice with the highest screening rate suggests that practices can influence the uptake of breast cancer screening among their patients. Giving general practitioners a greater role in breast cancer screening, either by offering them financial incentives or by giving them clerical support to check prior notification lists and contact nonattenders, may also help to increase breast cancer screening rates.

Equity in the NHS. Monitoring and promoting equity in primary and secondary care.

Although need is often assumed to be the most important factor in determining the use of health services, there are many inequities in the provision and use of NHS services in both primary and secondary care. For example, existing data from district child health information services have been combined with census data for small areas to show wide variations in immunisation rates between affluent and deprived areas. Purchasers of health care are already responsible for assessing health needs and evaluating services, and the process of monitoring equity is a logical extension of these activities. Routine data sources used to collect activity data in both primary and secondary care can be used to assess needs for care and monitor how well these needs are met. Purchasers and providers should collaborate to improve the usefulness of these routine data and to develop a framework for monitoring and promoting equity more systematically.

Using patient and general practice characteristics to explain variations in cervical smear uptake rates.

OBJECTIVES: To produce practice and patient variables for general practices from census and family health services authority data, and to determine the importance of these variables in explaining variation in cervical smear uptake rates between practices. DESIGN: Population based study examining variations in cervical smear uptake rates among 126 general practices using routine data. SETTING: Merton, Sutton, and Wandsworth Family Health Services Authority, which covers parts of inner and outer London. MAIN OUTCOME MEASURE: Percentage of women aged 25-64 years registered with a general practitioner who had undergone a cervical smear test during the five and a half years preceding 31 March 1992. RESULTS: Cervical smear uptake rates varied from 16.5% to 94.1%. The estimated percentage of practice population from ethnic minority groups correlated negatively with uptake rates (r = -0.42), as did variables associated with social deprivation such as overcrowding (r = -0.42), not owning a car (r = -0.41), and unemployment (r = -0.40). Percentage of practice population under 5 years of age correlated positively with uptake rate (r = 0.42). Rates were higher in practices with a female partner than in those without (66.6% v 49.1%; difference 17.5% (95% confidence interval 10.5% to 24.5%)), and in computerised than in non-computerised practices (64.5% v 50.5%; 14.0% (6.4% to 21.6%)). Rates were higher in larger practices. In a stepwise multiple regression model that explained 52% of variation, five factors were significant predictors of uptake rates: presence of a female partner; children under 5; overcrowding; number of women aged 35-44 as percentage of all women aged 25-64; change of address in past year. CONCLUSIONS: Over half of variation in cervical smear uptake rates can be explained by patient and practice variables derived from census and family health services authority data; these variables may have a role in explaining variations in performance of general practices and in producing adjusted measures of practice performance. Practices with a female partner had substantially higher uptake rates.

Trends in death rates and registration rates for prostate cancer in England and Wales.

OBJECTIVE: To describe trends in deaths from prostate cancer between 1970 and 1990, and trends in registrations of prostate cancer between 1971 and 1986. METHODS: Data on prostate cancer deaths and registrations were obtained from the Office of Population Censuses and Surveys, and age specific rates were calculated. RESULTS: The number of deaths from prostate cancer rose by 107% between 1970 and 1990, from 3906 to 8098. The number of registrations of prostate cancer rose by 75% between 1971 and 1986, from 5819 to 10,180. Age-specific death rates and registration rates also increased but by a smaller amount than the rise in absolute numbers. CONCLUSIONS: A component of the increase seen in both the number of prostate cancer deaths and registrations can be explained by a concomitant increase in the elderly male population, the group at highest risk, but the rises seen in rates are more difficult to explain. The rises are likely to have had considerable implications for the workload of urologists and should be taken into account when planning future health services. With further increases expected over the next decade in the elderly male population, deaths and registrations from prostate cancer will continue to rise. Research will be required to determine possible reasons for the increase seen in prostate cancer rates over the last 20 years, to determine the true incidence and prevalence of prostate cancer in the general population and to identify possible aetiological factors.

Audit of near patient cholesterol testing in occupational health clinics.

An audit of near patient cholesterol testing was carried out in occupational health clinics. The aims were to examine the statistical agreement between Reflotron and laboratory measurements of blood cholesterol and to formulate a policy for the use of Reflotrons in cholesterol testing. Three hundred and fifty-two staff members attending occupational health clinics over a period of 10 months had blood taken for both Reflotron and laboratory measurements. The correlation between the two methods was 0.95. The Reflotron had a negative bias compared to the laboratory, with the mean difference between the two methods of measurement being -0.21 mmol/l (95 per cent confidence interval -0.18 to -0.25 mmol/l). Despite the high correlation coefficient and small mean difference, the scatter of Reflotron-laboratory differences was broad, with 95 per cent of the differences lying in the range of 0.95 mmol/l below to 0.52 mmol/l above the laboratory result. For Reflotron results of 5.50 mmol/l and greater, the sensitivity and specificity of the Reflotron in detecting subjects with laboratory cholesterol levels greater than 6.5 mmol/l were 100 per cent and 70 per cent respectively. The laboratory participated in two external quality assessment schemes for cholesterol testing during the course of the audit and all the results of these fell within the acceptable limits. The audit demonstrated that the Reflotron was too imprecise to be used to give accurate measurements of blood cholesterol. However, providing a suitable Reflotron result above which patients were sent for confirmatory laboratory testing was selected, it was an acceptable screening device in the detection of hypercholesterolaemia. Other Reflotron users should consider carrying out similar audits.

An outbreak of hepatitis A in Gloucester, UK.

During an outbreak of hepatitis A that occurred in Gloucester, UK between September 1989 and January 1991, 162 clinical cases were identified through notifications and laboratory reports, a monthly attack rate of 1.05 per 10,000 residents. The highest attack rate was seen in 5-14-year-olds. There were significant correlations between hepatitis A attack rates in the electoral wards of Gloucester and with the Jarman UPA 8 scores for the wards and with overcrowding, unemployment, under 5-year-olds and ethnic minority. The use of human normal immune globulin prophylaxis (HNIG) for household contacts was unsuccessful in ending the outbreak, partly because only one third of cases reported a household contact with recent hepatitis A. Our experience does not support the use of HNIG in stopping community-wide outbreaks of hepatitis A. Two public health campaigns were mounted during the outbreak; both were followed by a fall in the number of cases. Greater priority should be given to the implementation and evaluation of public health campaigns in future community-wide outbreaks of hepatitis A.

Salivary antibody testing in a school outbreak of hepatitis A.

During a community-wide outbreak of hepatitis A in Gloucester, UK there was a high attack rate in children attending two city primary schools and a pre-school centre sharing the same site. In September 1990, saliva specimens were collected from 478 (85%) of the 562 children. The prevalence of antibody to hepatitis A virus (anti-HAV), as determined by saliva testing, was 29.6%; highest prevalences were seen in 5-6-year-olds and in children from that area of the city at the centre of the community-wide outbreak. The proportion of immune children with a history of clinical hepatitis varied with age from 1 in 42.7 of under-5-year-olds to 1 in 4.7 of 8-10-year-olds. Six children who received prophylaxis with human normal immune globulin (HNIG) because they were household contacts of cases subsequently became infected. Since there was evidence of transmission outside the school environment it is unlikely that a policy of universal prophylaxis within the schools would have stopped the outbreak. Mass prophylaxis in school outbreaks is only likely to be effective if most transmission is occurring at school and if the target population can be clearly defined. Salivary antibody testing is a simple, practical and acceptable procedure in young children. Salivary antibody surveys in conjunction with vaccination against hepatitis A should provide a cost-effective method for control of future outbreaks.

Hepatic perfusion index in cirrhotic livers--investigation of imaging and analytical procedures.

Dynamic hepatic scintigraphy was performed in a group of cirrhotic patients to evaluate the optimum imaging and analytical procedures necessary for the measurement of the hepatic perfusion index (HPI). Patients were studied in the posterior (n = 19) and the anterior (n = 14), positions, with either 0.2 or 0.5 ml of 99Tcm sulphur colloid administered as a rapid bolus injection. In each subject, three ROIs (small, medium and large) were drawn over the liver, and time-activity perfusion curves were generated. Analytical techniques were developed to allow flexibility in selecting the arterial and portal venous phases of the liver perfusion curve. The quality of the bolus, expressed as the full width at half-maximum of the left ventricular time--activity curve, was independent of the bolus volumes and patient positioning. The dispersion in the data and the inter-observer variation were less in the anterior view using medium and large ROIs, compared with the anterior small ROI and all the posterior ROI sizes. A time delay between liver and kidney arterial phases, if ignored, produced statistically significant effects on the values of the HPI. We conclude that HPI investigations are best performed in the anterior projection. Data analysis using a large liver ROI is preferred, and flexible data-processing techniques are recommended, particularly in the presence of a liver and kidney arterial time delay.