[Correlation between Area-Level Sociodemographic Patterns and Estimates of Need for Medical Care]. / Korrelation zwischen räumlichen Sozialstrukturfaktoren und Indikatoren des medizinischen Versorgungsbedarfs.

OBJECTIVE: Besides the known determinants age, sex, and morbidity, regional sociodemographic factors may be important for the level of health care needs. This study proposes a possible characterisation of area-level sociodemographic patterns and proves their association to variation in morbidity, mortality and health service utilisation. METHODS: We used the 412 counties of Germany as unit of analysis. To describe area-level sociodemographic patterns a factor analysis was conducted on a set of 27 indicators from official statistics. Two factors were retained and rotated according to the Varimax criteria, which explained 34.2 and 33.0% of variance. Mortality, utilisation of inpatient health services as well as parameters of the nationwide outpatient claims data [relative risk score (RRS) and the level of health care use (LB)] served as determinants of need for medical care and were correlated to the extracted factors. RESULTS: Factor 1 describes regional disparities in socio-economic and health status variables and is called socio-economic health index (SGX). Factor 2 characterises the spatial distribution of interregional migration and household size and is called urbanity index (UX). There was a strong positive correlation between SGX and RRS (r=0.77), mortality (r=0.68 and r=0.78 for overall and premature death rate) and inpatient health care use (r=0.62). UX was not correlated with RRS but weakly inversely correlated with inpatient health care use (r=-0.28). Both SGX and UX were significantly correlated to the level of outpatient health care use (r=0.39 and r=0.40). Stratification of LB by type of practitioner revealed that SGX was mainly associated with health care provided by general practitioners while UX was linked to health care provided by specialists, particularly psychotherapists. CONCLUSIONS: The extracted factors to describe area-level sociodemographic patterns showed distinct correlations to indicators for medical care use. While SGX was mainly associated with overall morbidity, UX showed consistent relations with specific medical care needs, which may be linked to urban living conditions. Therefore, UX may refer to need for care independently from overall morbidity on the one hand and to structural specifics in health care services on the other hand. The meaning of SGX and UX needs to be further investigated taking additional determining factors into account.

[What do functionally defined populations contribute to the explanation of regional differences in medical care?]. / Welchen Beitrag liefern funktional definierte Populationen zur Erklärung regionaler Unterschiede in der medizinischen Versorgung?

Geographic variation in health care is increasingly subject to analysis and health policy aiming at the suitable allocation of resources and the reduction of unwarranted variation for the patient populations concerned. As in the case of area-level indicators, in most cases populations are geographically defined. The concept of geographically defined populations, however, may be self-limiting with respect to identifying the potential for improvement. As an alternative, we explored how a functional definition of populations would support defining the scope for reducing unwarranted geographical variations. Given that patients in Germany have virtually no limits in accessing physicians of their choice, we adapted a method that has been developed in the United States to create virtual networks of physicians based on commonly treated patients. Using the physician claims data under statutory insurance, which covers 90% of the population, we defined 43,006 populations-and networks-in 2010. We found that there is considerable variation between the population in terms of their risk structure and the share of the primary care practice in the total services provided. Moreover, there are marked differences in the size and structure of networks between cities, densely populated regions, and rural regions. We analyzed the variation for two area-level indicators: the proportion of diabetics with at least one HbA1c test per year for diabetics, and the proportion of patients with low back pain undergoing computed tomography and/or magnetic resonance imaging. Variation at the level of functionally defined populations proved to be larger than for geographically defined populations. The pattern of distribution gives evidence on the degree to which consensus targets could be reached and which networks need to be addressed in order to reduce unwarranted regional variation. The concept of functionally defined populations needs to be further developed before implementation.

[Patient shifting between inpatient care and ambulatory care - exploring methods to measure the relevance of patient shifting]. / Leistungsverlagerungen zwischen Krankenhäusern und niedergelassenen Ärzten - Ein Beitrag zur Methodik der Messung von Verlagerungseffekten und grobe Abschätzung der Bedeutung.

BACKGROUND: The financial dimension of long term changes in the medical division of labour between inpatient care and ambulatory care has yet to be systematically monitored. While this is of general interest for health systems research there is now an acute need for the development of reliable methods to measure the effects of shifts in care as part of physician payment reform in Germany. The Social Code Book V (§ 87a Sec 4 No 3) requires the collective contracting partners to determine risk adjusted payment targets for regional populations thereby also taking into account shifts between inpatient and ambulatory care. METHODS: Using predictive modelling patient groups are identified which meet the following two criteria in two consecutive years: 1) increases in actual cost exceeded expected cost in sector a while expected cost exceeded actual cost in sector b; 2) absolute number of cases increased in sector a and decreased in sector b. The model is based on the definition of a limited set of risk groups as defined by the risk adjustment scheme applied to German sickness funds. For our study these risk groups have been calibrated separately for each sector creating a common set of predictors. The second criterion focuses the approach on patient shifting as the most tangible effect of shifted care. In order to quantify the effect of patient shifting another predictive modelling approach is developed using the difference between expected and actual inpatient cases per risk group to estimate the resulting change in ambulatory case load. The cost of the additional case load per risk group is calculated for Germany based on population-based claims data (77 million patients). RESULTS: The criteria for patient shifting as defined above apply to 26 out of 95 risk groups. At the level of risk groups hardly any patient shifting into ambulatory care was detected. On average for each patient with the respective risk factors 0.6 additional cases in ambulatory care were estimated as result of reduced incidence of inpatient care. In total the additional cost associated with patient shifting from inpatient care to ambulatory care was estimated 424 million € (2007). This represents 1.5% of total spending on ambulatory care and underlines the importance of the issue to health services research. Roughly 80% of this amount is likely to be eligible to physician services relevant to morbidity adjusted targets under payment reform. Prior to implementation as a payment formula, however, the approach needs to be based on a comprehensive risk adjustment model and needs further refinement.