Bärbel-Maria Kurth

The challenge of comprehensively mapping children's health in a nation-wide health survey: Design of the German KiGGS-Study

BackgroundFrom May 2003 to May 2006, the Robert Koch Institute conducted the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). Aim of this first nationwide interview and examination survey was to collect comprehensive data on the health status of children and adolescents aged 0 to 17 years.Methods/DesignParticipants were enrolled in two steps: first, 167 study locations (sample points) were chosen; second, subjects were randomly selected from the official registers of local residents. The survey involved questionnaires filled in by parents and parallel questionnaires for children aged 11 years and older, physical examinations and tests, and a computer assisted personal interview performed by study physicians. A wide range of blood and urine testing was carried out at central laboratories. A total of 17 641 children and adolescents were surveyed – 8985 boys and 8656 girls. The proportion of sample neutral drop-outs was 5.3%. The response rate was 66.6%.DiscussionThe response rate showed little variation between age groups and sexes, but marked variation between resident aliens and Germans, between inhabitants of cities with a population of 100 000 or more and sample points with fewer inhabitants, as well as between the old West German states and the former East German states. By analysing the short non-responder questionnaires it was proven that the collected data give comprehensive and nationally representative evidence on the health status of children and adolescents aged 0 to 17 years.

German health interview and examination survey for adults (DEGS) - design, objectives and implementation of the first data collection wave

BackgroundThe German Health Interview and Examination Survey for Adults (DEGS) is part of the recently established national health monitoring conducted by the Robert Koch Institute. DEGS combines a nationally representative periodic health survey and a longitudinal study based on follow-up of survey participants. Funding is provided by the German Ministry of Health and supplemented for specific research topics from other sources.Methods/designThe first DEGS wave of data collection (DEGS1) extended from November 2008 to December 2011. Overall, 8152 men and women participated. Of these, 3959 persons already participated in the German National Health Interview and Examination Survey 1998 (GNHIES98) at which time they were 18–79 years of age. Another 4193 persons 18–79 years of age were recruited for DEGS1 in 2008–2011 based on two-stage stratified random sampling from local population registries. Health data and context variables were collected using standardized computer assisted personal interviews, self-administered questionnaires, and standardized measurements and tests. In order to keep survey results representative for the population aged 18–79 years, results will be weighted by survey-specific weighting factors considering sampling and drop-out probabilities as well as deviations between the design-weighted net sample and German population statistics 2010.DiscussionDEGS aims to establish a nationally representative data base on health of adults in Germany. This health data platform will be used for continuous health reporting and health care research. The results will help to support health policy planning and evaluation. Repeated cross-sectional surveys will permit analyses of time trends in morbidity, functional capacity levels, disability, and health risks and resources. Follow-up of study participants will provide the opportunity to study trajectories of health and disability. A special focus lies on chronic diseases including asthma, allergies, cardiovascular conditions, diabetes mellitus, and musculoskeletal diseases. Other core topics include vaccine-preventable diseases and immunization status, nutritional deficiencies, health in older age, and the association between health-related behavior and mental health.

Potential determinants of obesity among children and adolescents in Germany: results from the cross-sectional KiGGS study

BackgroundObesity among children and adolescents is a growing public health problem. The aim of the present paper is to identify potential determinants of obesity and risk groups among 3- to 17-year old children and adolescents to provide a basis for effective prevention strategies.MethodsData were collected in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), a nationally representative and comprehensive data set on health behaviour and health status of German children and adolescents. Body height and weight were measured and body mass index (BMI) was classified according to IOTF cut-off points. Statistical analyses were conducted on 13,450 non-underweight children and adolescents aged 3 to 17 years. The association between overweight, obesity and several potential determinants was analysed for this group as well as for three socio-economic status (SES) groups. A multiple logistic regression model with obesity as the dependent variable was also calculated.ResultsThe strongest association with obesity was observed for parental overweight and for low SES. Furthermore, a positive association with both overweight (including obesity) and obesity was seen for maternal smoking during pregnancy, high weight gain during pregnancy (only for mothers of normal weight), high birth weight, and high media consumption. In addition, high intakes of meat and sausages, total beverages, water and tea, total food and beverages, as well as energy-providing food and beverages were significantly associated with overweight as well as with obesity. Long sleep time was negatively associated with obesity among 3- to 10-year olds. Determinants of obesity occurred more often among children and adolescents with low SES.ConclusionParental overweight and a low SES are major potential determinants of obesity. Families with these characteristics should be focused on in obesity prevention.

Gesundheitsmonitoring am Robert Koch-Institut

Since January 2008, the Robert Koch Institute (RKI) has been administrating a Health Monitoring System, i.e., health examination surveys and health interview surveys with longitudinal components being alternatingly performed. These surveys are continuously accompanied by annual cross-sectional interview surveys of the population living in Germany. The content and structure of the Health Monitoring System is explained and the actual on-going surveys are described in this paper. An overview of future surveys and their integration within the European context demonstrates the new quality in utilizing the data obtained by longitudinal and cross-sectional analyses for health reporting, health policies and health sciences.ZusammenfassungSeit Januar 2008 gibt es am Robert Koch-Institut (RKI) ein Gesundheitsmonitoring, das auf alternierend durchzuführenden Untersuchungs- beziehungsweise Befragungssurveys mit Längsschnittkomponenten beruht und kontinuierlich durch jährliche Querschnittsbefragungen der in Deutschland lebenden Bevölkerung begleitet wird. Das inhaltliche und strukturelle Konzept dieses Monitoringsystems wird erläutert, die aktuell laufenden Surveys werden vorgestellt. Ein Ausblick auf künftige Erhebungen und die Einordnung in den europäischen Kontext verdeutlicht die qualitativ neuen Nutzungsmöglichkeiten der im Längsschnitt und Querschnitt erhobenen Daten für die Gesundheitsberichterstattung, die Gesundheitspolitik und die Gesundheitswissenschaften.AbstractSince January 2008, the Robert Koch Institute (RKI) has been administrating a Health Monitoring System, i.e., health examination surveys and health interview surveys with longitudinal components being alternatingly performed. These surveys are continuously accompanied by annual cross-sectional interview surveys of the population living in Germany. The content and structure of the Health Monitoring System is explained and the actual on-going surveys are described in this paper. An overview of future surveys and their integration within the European context demonstrates the new quality in utilizing the data obtained by longitudinal and cross-sectional analyses for health reporting, health policies and health sciences.

Body mass index percentiles for children and adolescents in Germany based on a nationally representative sample (KiGGS 2003―2006)

Objective:To present body mass index (BMI) percentiles representative for children in Germany and to compare them with the currently used percentiles by Kromeyer–Hauschild (KH) and international percentiles of the World Health Organisation (WHO) and the International Obesity Task Force (IOTF).Methods:Representative examination survey of 17 641 children and adolescents aged 0–17 years living in Germany (KiGGS 2003–2006 study, response rate 67%) with standardized measurement of height and weight.Results:Generally, BMI in KiGGS was higher than in the reference populations from previous decades. KiGGS shows an asymmetric upward shift of the BMI distribution from about age 6 years and an earlier adiposity rebound compared with KH. The BMI peak in the first year of life is shown by KiGGS and WHO, but much less by KH. The cut-offs for overweight and obesity determined with the IOTF methodology in KiGGS (percentiles corresponding to BMI 25 and 30 kg/m2 at 18 years of age) were similar to IOTF cut-offs from age 18 to 10 years but systematically lower for younger children.Conclusions:The KiGGS BMI percentiles appear more valid for Germany than present alternatives and should be used for population monitoring. Despite their methodological limitations, the general shape of the older German KH references is confirmed by KiGGS for the ages 2–17 years. In order not to obscure the increase in obesity rates in the last decades, we therefore propose to continue using KH for individual diagnosis and estimation of the prevalence of overweight and obesity in this age range.

Predictors for ambulatory medical care utilization in Germany

ZusammenfassungDer Artikel befasst sich mit der Analyse möglicher Einflüsse auf die Inanspruchnahme niedergelassener Ärzte durch die Bevölkerung in einem Jahr. Die theoretische Grundlage bildet das Verhaltensmodell nach R. M. Andersen, das die Einflussgrößen der Inanspruchnahme in die Komponenten „Predisposing“, „Enabling“ und „Need“ konzeptionell unterteilt. Die Datengrundlage ist eine repräsentative Untersuchung der erwachsenen Wohnbevölkerung in der Bundesrepublik Deutschland (Bundes-Gesundheitssurvey 1998), die um regionale Strukturdaten und aggregierte Daten aus der vertragsärztlichen Abrechnung erweitert wurde. Indikatoren für die ambulante Inanspruchnahme sind die erfragten Anzahlen der Kontakte bei niedergelassenen Ärzten insgesamt, der kontaktierten Fachgruppen, der Kontakte bei Internisten und der Kontakte bei Allgemeinmedizinern in den letzten 12 Monaten. Es zeigen sich neben den erwarteten starken Einflüssen der Need-Faktoren wie Morbidität und gesundheitsbezogener Lebensqualität auch Predisposing-Faktoren wie Region, Stadt/Land, Alter und Geschlecht als signifikante Einflussfaktoren auf die Inanspruchnahme niedergelassener Ärzte. Hinsichtlich der Enabling-Faktoren lässt sich festhalten, dass Personen mit Hausarzt entgegen der erhofften Steuerungsfunktion der Hausärzte insgesamt eine höhere Inanspruchnahme aufweisen. Aus den Ergebnissen werden Empfehlungen zu möglichen Steuerungsansätzen abgeleitet und einige Grenzen der Beeinflussbarkeit des Inanspruchnahmegeschehens aufgezeigt.AbstractAn analysis of the possible influences on primary health care utilization is made. The theoretical framework is the health behavioural model of R. M. Andersen, dividing the influencing variables into the components predisposing characteristics, enabling resources, and need factors. The study was based on data from the German National Health Examination and Interview Survey of the adult population in 1998. The data were linked to regional structural data and aggregated account data. The total number of contacts, the number of contacts with general practitioners and internists, and the number of different specialists contacted in the last 12 months, as calculated from interview data, were used to indicate primary health care utilization. In addition to the expected strong influence of need factors such as morbidity and health-related quality of life, the predisposing characteristics such as region, urban/rural, age, and gender have a significant influence on the primary care utilization. With regard to the enabling factors, persons with a family doctor had more contacts overall, which contrasts with the family doctor’s assumed gate-keeper function. From the results of the study, recommendations on possible regulatory measures are given, but also some restrictions for influencing the number of contacts are pointed out.

Einflussfaktoren auf die ambulante Inanspruchnahme in Deutschland

ZusammenfassungDer Artikel befasst sich mit der Analyse möglicher Einflüsse auf die Inanspruchnahme niedergelassener Ärzte durch die Bevölkerung in einem Jahr. Die theoretische Grundlage bildet das Verhaltensmodell nach R. M. Andersen, das die Einflussgrößen der Inanspruchnahme in die Komponenten „Predisposing“, „Enabling“ und „Need“ konzeptionell unterteilt. Die Datengrundlage ist eine repräsentative Untersuchung der erwachsenen Wohnbevölkerung in der Bundesrepublik Deutschland (Bundes-Gesundheitssurvey 1998), die um regionale Strukturdaten und aggregierte Daten aus der vertragsärztlichen Abrechnung erweitert wurde. Indikatoren für die ambulante Inanspruchnahme sind die erfragten Anzahlen der Kontakte bei niedergelassenen Ärzten insgesamt, der kontaktierten Fachgruppen, der Kontakte bei Internisten und der Kontakte bei Allgemeinmedizinern in den letzten 12 Monaten. Es zeigen sich neben den erwarteten starken Einflüssen der Need-Faktoren wie Morbidität und gesundheitsbezogener Lebensqualität auch Predisposing-Faktoren wie Region, Stadt/Land, Alter und Geschlecht als signifikante Einflussfaktoren auf die Inanspruchnahme niedergelassener Ärzte. Hinsichtlich der Enabling-Faktoren lässt sich festhalten, dass Personen mit Hausarzt entgegen der erhofften Steuerungsfunktion der Hausärzte insgesamt eine höhere Inanspruchnahme aufweisen. Aus den Ergebnissen werden Empfehlungen zu möglichen Steuerungsansätzen abgeleitet und einige Grenzen der Beeinflussbarkeit des Inanspruchnahmegeschehens aufgezeigt.AbstractAn analysis of the possible influences on primary health care utilization is made. The theoretical framework is the health behavioural model of R. M. Andersen, dividing the influencing variables into the components predisposing characteristics, enabling resources, and need factors. The study was based on data from the German National Health Examination and Interview Survey of the adult population in 1998. The data were linked to regional structural data and aggregated account data. The total number of contacts, the number of contacts with general practitioners and internists, and the number of different specialists contacted in the last 12 months, as calculated from interview data, were used to indicate primary health care utilization. In addition to the expected strong influence of need factors such as morbidity and health-related quality of life, the predisposing characteristics such as region, urban/rural, age, and gender have a significant influence on the primary care utilization. With regard to the enabling factors, persons with a family doctor had more contacts overall, which contrasts with the family doctor’s assumed gate-keeper function. From the results of the study, recommendations on possible regulatory measures are given, but also some restrictions for influencing the number of contacts are pointed out.

Measuring adolescents' HRQoL via self reports and parent proxy reports: an evaluation of the psychometric properties of both versions of the KINDL-R instrument.

BackgroundSeveral instruments are available to assess childrens health-related quality of life (HRQoL) based on self reports as well as proxy reports from parents. Previous studies have found only low-to-moderate agreement between self and proxy reports, but few studies have explicitly compared the psychometric qualities of both. This study compares the reliability, factorial validity and convergent and known group validity of the self-report and parent-report versions of the HRQoL KINDL-R questionnaire for children and adolescents.MethodsWithin the nationally representative cross-sectional German Health Interview and Examination Survey for Children and Adolescents (KiGGS), 6,813 children and adolescents aged 11 to 17 years completed the KINDL-R generic HRQoL instrument while their parents answered the KINDL proxy version (both in paper-and-pencil versions). Cronbachs alpha and confirmatory factor-analysis models (linear structural equation model) were obtained. Convergent and discriminant validity were assessed by calculating the Pearsons correlation coefficient for the Strengths and Difficulties Questionnaire. Known-groups differences were examined (ANOVA) for obese children and children with a lower familial socio-economic status.ResultsThe parent reports achieved slightly higher Cronbachs alpha values for the total score (0.86 vs. 0.83) and most sub-scores. Confirmatory factor analysis revealed an acceptable fit of the six-dimensional measurement model of the KINDL for the parent (RMSEA = 0.07) and child reports (RMSEA = 0.06). Factorial invariance across the two versions did not hold with regards to the pattern of loadings, the item errors and the covariation between latent concepts. However the magnitude of the differences was rather small. The parent report version achieved slightly higher convergent validity (r = 0.44 – 0.63 vs. r = 0.33 – 0.59) in the Strengths and Difficulties Questionnaire. No clear differences were observed for known-groups validity.ConclusionOur study showed that parent proxy reports and child self reports on the childs HRQoL slightly differ with regards to how the perceptions, evaluations and possibly the affective resonance of each group are structured and internally consistent. Overall, the parent reports achieved slightly higher reliability and thus are favoured for the examination of small samples. No version was universally superior with regards to the validity of the measurements. Whenever possible, childrens HRQoL should be measured via both sources of information.

[The prevalence of attention-deficit/hyperactivity disorder (ADHD) among children and adolescents in Germany. Initial results from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS)].

ZusammenfassungLeitsymptome der Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung (ADHS) sind Unaufmerksamkeit, motorische Unruhe und Impulsivität. ADHS wird ätiologisch vorrangig auf genetische Ursachen zurückgeführt und bringt eine erhebliche psychosoziale Problematik für die Betroffenen und ihr soziales Umfeld mit sich. Im Rahmen des Kinder- und Jugendgesundheitssurvey (KiGGS) beantworteten die Eltern von insgesamt 7569 Jungen und 7267 Mädchen im Alter von 3–17 Jahren schriftlich einen Fragebogen, der unter anderem eine ADHS-Diagnosefrage und den Strengths and Difficulties Questionnaire (SDQ) enthielt. Zusätzlich erfolgten Verhaltensbeobachtungen von 7919 Kindern (Altersspanne 3–11 Jahre) während der medizinischphysikalischen Tests. Als ADHS-Fälle wurden Teilnehmer eingestuft, deren Eltern eine jemals von einem Arzt oder Psychologen gestellte ADHS-Diagnose angegeben hatten. Als ADHS-Verdachtsfälle wurden Teilnehmer betrachtet, die Werte von ≥ 7 auf der Unaufmerksamkeits-/Hyperaktivitätsskala des SDQ (Elternurteil) aufwiesen. Bei insgesamt 4,8 % der Kinder und Jugendlichen wurde jemals ADHS diagnostiziert. Weitere 4,9 % der Teilnehmer können als Verdachtsfälle gelten. Bei Jungen wurde ADHS um den Faktor 4,3 häufiger diagnostiziert als bei Mädchen. Bereits bei 1,8 % der Teilnehmer im Vorschulalter wurde ADHS diagnostiziert. Im Grundschulalter (7–10 Jahre) steigt die Diagnosehäufigkeit stark. Im Alter von 11–17 Jahren wurde bei jedem zehnten Jungen und jedem 43. Mädchen jemals ADHS diagnostiziert. ADHS wurde häufiger bei Teilnehmern mit niedrigem sozioökonomischem Status diagnostiziert als bei Teilnehmern mit hohem Status. Von Migranten wird seltener über eine ADHS-Diagnose berichtetet, sie sind jedoch häufiger unter den Verdachtsfällen. Diese Diskrepanz könnte auf eine Unterdiagnostizierung oder auf Inanspruchnahmeeffekte bei Migranten hinweisen. Die kurz- und langfristigen medizinischen, sozialen und gesundheitsökonomischen Konsequenzen von ADHS verdeutlichen die hohe Public-Health-Relevanz der Störung. Der hohe Anteil genetischer Faktoren an der Ätiologie der ADHS lässt hier vor allem an Maßnahmen der Sekundär-(Früherkennung und Frühförderung) und Tertiärprävention denken. Mit weiteren Auswertungen der KiGGS-Daten können Risikogruppen zukünftig genauer identifiziert und Präventionsansätze weiterentwickelt werden.AbstractThe cardinal symptoms of attention-deficit/hyperactivity disorder (ADHD) are inattention, hyperactivity and impulsivity. Etiologically, ADHD is mainly put down to genetic causes; it entails a considerable range of psychosocial problems for those affected and their social environment. The parents of a total of 7,569 boys (B) and 7,267 girls (G) aged 3–17 who took part in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) answered a self-administered questionnaire including an ADHD diagnosis question and the Strengths and Difficulties Questionnaire (SDQ). In addition behavioural observations of 7,919 children (aged 3–11) were carried out during the medical and physical tests. Participants whose parents reported that they had ever been given an ADHD diagnosis by a doctor or psychologist were classified as ADHD cases. Participants were classified as suspected cases of ADHD if they had a value of ≥7 on the SDQ inattention/hyperactivity scale. ADHD had ever been diagnosed in 4.8 % of the children and adolescents altogether (B: 7.7 %, G: 1.8 %). Another 4.9 % of the participants can be considered as suspected cases. Already 1.8 % of the preeschoolers had been given an ADHD diagnosis. At primary school age (7–10 years old) the frequency of diagnosis rises sharply. At age 11–17, ADHD had ever been diagnosed in 1 in 10 boys and 1 in 43 girls. ADHD had been diagnosed significantly more frequently among participants of low socio-economic status (SES) than among participants of high SES. A diagnosis of ADHD is reported less often for migrants, they rank more frequently among the suspected cases. The discrepancy between confirmed and suspected cases of ADHD among migrants may point to lower diagnosis rates or lower utilization of medical services. The short- and long-term medical, social and health-economic effects of ADHD illustrate the major public health relevance of the disorder. As for prevention, the high share of genetic factors in ADHD etiology primarily suggests secondary prevention (early support and early diagnosis) and tertiary prevention measures. Further analysis of the KiGGS data could prospectively identify risk groups more precisely and refine preventional approaches.

A comparison of Framingham and SCORE-based cardiovascular risk estimates in participants of the German National Health Interview and Examination Survey 1998.

Background Overestimation of risk by Framingham risk functions not only in southern but also in northern European populations including Germany, has led to the development of the SCORE risk estimation model. Design Data of the German National Health Interview and Examination Survey 1998 was used to determine whether SCORE leads to lower estimates of the 10-year absolute risk of fatal cardiovascular disease and fatal coronary heart disease than a Framingham model. Predicted numbers of events were compared with approximations based on national mortality statistics. Methods Inclusion criteria followed the recommendations for the use of SCORE: age 30 to 69 years, no previous history of cardiovascular disease and no markedly raised levels of single risk factors (leaving 1811 men and 1955 women for analysis). Results The SCORE model for high-risk regions (SCORE-HIGH, which is recommended for Germany pending calibration with national data) predicted the highest number of events, followed by the estimations with mortality statistics, the Framingham model and SCORE-LOW (87 fatal cardiovascular disease events versus 77, 62 and 47; fatal coronary heart disease events 62 versus 46, 46 and 30). Agreement on high-risk status, defined as the 10-year risk of fatal cardiovascular disease of 5% or higher now or if extrapolated to age 60, was moderate for both men and women (≤ 0.52 and 0.42 for Framingham and SCORE-HIGH). Conclusions Our results suggest that SCORE-HIGH may overestimate absolute risk of fatal coronary heart disease and cardiovascular disease in Germany and may need calibration. Furthermore, the limitations of current risk prediction tools emphasize the ongoing need for comprehensive, high-quality and timely European cohort data.