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Objectives International guidelines recommend additional salt supplementation during infancy in classic congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. The influence of corticoid medication and growth has not been assessed. Aim To investigate the current use of salt supplementation, fludrocortisone (FC) and hydrocortisone (HC) dosage as well as weight, height, BMI and blood pressure (BP) in CAH children aged 0–3 years. Methods Retrospective multicentre analysis using data from the I-CAH registry. Salt-treated (ST) and non-salt-treated (NST) children were compared regarding FC and HC dosage, weight, height and BP at 0, 3, 6, 9, 12, 18, 24, 30, and 36 months. Results We analysed 2483 visits of 331 patients born after year 2000 in 13 countries (male, n = 145) with 203 ST patients (61%). NST children had significantly higher FC dosages at 1.5–4.5 months and higher HC dosages until 1.5 months of age. No differences in weight, length and BP between subgroups were observed. Children of the whole cohort showed increased BMI-SDS during the study period and about half of the reported BP readings were >P95. Conclusion In children treated with additional salt supplementation, FC and HC dosages are lower during the first months of life but without differences in weight, length and BP until 3 years of age compared to NST children. All children showed an increase in BMI-SDS and a high rate of BP readings >P95 until 3 years, indicating the start of weight gain and negative effects on blood pressure already in very early life.

Disorders of or differences in sexual development (DSD) are defined by congenital conditions in which development of chromosomal, gonadal, or anatomic sex are atypical. Here, we report on monochorionic diamniotic twins delivered by Caesarean section in the 36th week of pregnancy. Monochorionic twins are usually monozygous and thus should have the same sexual differentiation. In this case, one twin had female external genitalia, while the other showed ambiguous genitalia. At first, a diagnosis of mixed gonadal dysgenesis was proposed because of the obvious sexual discrepancy between the supposedly monozygous twins. Cytogenetic analyses were performed to assure the sex chromosome status for both children. Male and female cells were found subsequently in both children. While hematopoietic chimerism of monochorionic dizygous twins as a result of twin-to-twin blood transfusion is a rare but already well documented phenomenon, to our knowledge this is the first case description of tetragametic chimerism that led to intersexuality.

Context Prenatal dexamethasone therapy is used in female foetuses with congenital adrenal hyperplasia to suppress androgen excess and prevent virilisation of the external genitalia. The traditional dexamethasone dose of 20 µg/kg/day has been used since decades without examination in clinical trials and is thus still considered experimental. Objective As the traditional dexamethasone dose potentially causes adverse effects in treated mothers and foetuses, we aimed to provide a rationale of a reduced dexamethasone dose in prenatal congenital adrenal hyperplasia therapy based on a pharmacokinetics-based modelling and simulation framework. Methods Based on a published dexamethasone dataset, a nonlinear mixed-effects model was developed describing maternal dexamethasone pharmacokinetics. In stochastic simulations (n = 1000), a typical pregnant population (n = 124) was split into two dosing arms receiving either the traditional 20 µg/kg/day dexamethasone dose or reduced doses between 5 and 10 µg/kg/day. Target maternal dexamethasone concentrations, identified from the literature, served as a threshold to be exceeded by 90% of mothers at a steady state to ensure foetal hypothalamic-pituitary-adrenal axis suppression. Results A two-compartment dexamethasone pharmacokinetic model was developed and subsequently evaluated to be fit for purpose. The simulations, including a sensitivity analysis regarding the assumed foetal:maternal dexamethasone concentration ratio, resulted in 7.5 µg/kg/day to be the minimum effective dose and thus our suggested dose. Conclusions We conclude that the traditional dexamethasone dose is three-fold higher than needed, possibly causing harm in treated foetuses and mothers. The clinical relevance and appropriateness of our recommended dose should be tested in a prospective clinical trial.

Objective Despite published guidelines no unified approach to hormone replacement in congenital adrenal hyperplasia (CAH) exists. We aimed to explore geographical and temporal variations in the treatment with glucocorticoids and mineralocorticoids in CAH. Design This retrospective multi-center study, including 31 centers (16 countries), analyzed data from the International-CAH Registry. Methods Data were collected from 461 patients aged 0–18 years with classic 21-hydroxylase deficiency (54.9% females) under follow-up between 1982 and 2018. Type, dose and timing of glucocorticoid and mineralocorticoid replacement were analyzed from 4174 patient visits. Results The most frequently used glucocorticoid was hydrocortisone (87.6%). Overall, there were significant differences between age groups with regards to daily hydrocortisone-equivalent dose for body surface, with the lowest dose (median with interquartile range) of 12.0 (10.0–14.5) mg/m2/day at age 1–8 years and the highest dose of 14.0 (11.6–17.4) mg/m2/day at age 12–18 years. Glucocorticoid doses decreased after 2010 in patients 0–8 years (P < 0.001) and remained unchanged in patients aged 8–18 years. Fludrocortisone was used in 92% of patients, with relative doses decreasing with age. A wide variation was observed among countries with regards to all aspects of steroid hormone replacement. Conclusions Data from the I-CAH Registry suggests international variations in hormone replacement therapy, with a tendency to treatment with high doses in children.

Background Although congenital adrenal hyperplasia (CAH) is known to be associated with adrenal crises (AC), its association with patient- or clinician-reported sick day episodes (SDE) is less clear. Methods Data on children with classic 21-hydroxylase deficiency CAH from 34 centers in 18 countries, of which 7 were Low or Middle Income Countries (LMIC) and 11 were High Income (HIC), were collected from the International CAH Registry and analyzed to examine the clinical factors associated with SDE and AC. Results A total of 518 children—with a median of 11 children (range 1, 53) per center—had 5388 visits evaluated over a total of 2300 patient-years. The median number of AC and SDE per patient-year per center was 0 (0, 3) and 0.4 (0.0, 13.3), respectively. Of the 1544 SDE, an AC was reported in 62 (4%), with no fatalities. Infectious illness was the most frequent precipitating event, reported in 1105 (72%) and 29 (47%) of SDE and AC, respectively. On comparing cases from LMIC and HIC, the median SDE per patient-year was 0.75 (0, 13.3) vs 0.11 (0, 12.0) (P Conclusions The real-world data that are collected within the I-CAH Registry show wide variability in the reported occurrence of adrenal insufficiency–related adverse events. As these data become increasingly used as a clinical benchmark in CAH care, there is a need for further research to improve and standardize the definition of SDE.

Funder: European Society for Paediatric Endocrinology Research Unit, OBJECTIVE: Congenital adrenal hyperplasia (CAH) requires exogenous steroid replacement. Treatment is commonly monitored by measuring 17-OH progesterone (17OHP) and androstenedione (D4). DESIGN: Retrospective cohort study using real-world data to evaluate 17OHP and D4 in relation to hydrocortisone (HC) dose in CAH patients treated in 14 countries. PATIENTS: Pseudonymized data from children with 21-hydroxylase deficiency (21OHD) recorded in the International CAH Registry. MEASUREMENTS: Assessments between January 2000 and October 2020 in patients prescribed HC were reviewed to summarise biomarkers 17OHP and D4 and HC dose. Longitudinal assessment of measures was carried out using linear mixed-effects models (LMEM). RESULTS: Cohort of 345 patients, 52.2% female, median age 4.3 years (interquartile range: 3.1-9.2) were taking a median 11.3 mg/m2 /day (8.6-14.4) of HC. Median 17OHP was 35.7 nmol/l (3.0-104.0). Median D4 under 12 years was 0 nmol/L (0-2.0) and above 12 years was 10.5 nmol/L (3.9-21.0). There were significant differences in biomarker values between centres (p < 0.05). Correlation between D4 and 17OHP was good in multiple regression with age (p < 0.001, R2 = 0.29). In longitudinal assessment, 17OHP levels did not change with age, whereas D4 levels increased with age (p < 0.001, R2 = 0.08). Neither biomarker varied directly with dose or weight (p > 0.05). Multivariate LMEM showed HC dose decreasing by 1.0 mg/m2 /day for every 1 point increase in weight standard deviation score. DISCUSSION: Registry data show large variability in 17OHP and D4 between centres. 17OHP correlates with D4 well when accounting for age. Prescribed HC dose per body surface area decreased with weight gain.

Disorders of sex development; Next-generation sequencing; Primary ovarian insufficiency Trastornos del desarrollo sexual; Secuenciación de próxima generación; Insuficiencia ovárica primaria Trastorns del desenvolupament sexual; Seqüenciació de nova generació; Insuficiència ovàrica primària Differences of sex development and maturation (SDM) represent a heterogeneous puzzle of rare conditions with a large genetic component whose management and treatment could be improved by an accurate classification of underlying molecular conditions, and next-generation sequencing (NGS) should represent the most appropriate approach. Therefore, we conducted a survey dedicated to the use and potential outcomes of NGS for SDM disorders diagnosis among the 53 health care providers (HCP) of the European Reference Network for rare endocrine conditions. The response rate was 49% with a total of 26 HCPs from 13 countries. All HCPs, except 1, performed NGS investigations for SDM disorders on 6720 patients, 3764 (56%) with differences of sex development (DSD), including 811 unexplained primary ovarian insufficiency, and 2956 (44%) with congenital hypogonadotropic hypogonadism (CHH). The approaches varied from targeted analysis of custom gene panels (range: 11–490 genes) in 81.5% of cases or whole exome sequencing with the extraction of a virtual panel in the remaining cases. These analyses were performed for diagnostic purposes in 21 HCPs, supported by the National Health Systems in 16 cases. The likelihood of finding a variant ranged between 7 and 60%, mainly depending upon the number of analysed genes or criteria used for reporting, most HCPs also reporting variants of uncertain significance. These data illustrate the status of genetic diagnosis of DSD and CHH across Europe. In most countries, these analyses are performed for diagnostic purposes, yielding highly variable results, thus suggesting the need for harmonization and general improvements of NGS approaches. This publication has been supported by Endo-ERN, which is co-funded by the European Union’s 3rd Health Programme (CHAFEA Framework Partnership Agreement No 739527).

Context Children with congenital adrenal hyperplasia (CAH) and adrenal insufficiency (AI) require daily hydrocortisone replacement with accurate dosing. Objective Prospective study of efficacy and safety of hydrocortisone granules in children with AI and CAH monitored by 17-OHP (17-hydroxyprogesterone) saliva profiles. Methods Seventeen children with CAH (9 male) and 1 with hypopituitarism (male), aged from birth to 6 years, had their hydrocortisone medication changed from pharmacy compounded capsules to hydrocortisone granules. Patients were followed prospectively for 2 years. In children with CAH, the therapy was adjusted by 17-OHP salivary profiles every 3 months. The following parameters were recorded: hydrocortisone dose, height, weight, pubertal status, adverse events, and incidence of adrenal crisis. Results The study medication was given thrice daily, and the median duration of treatment (range) was 795 (1–872) days, with 150 follow-up visits. Hydrocortisone doses were changed on 40/150 visits, with 32 based on salivary measurements and 8 on serum 17-OHP levels. The median daily mg/m2 hydrocortisone dose (range) at study entry for the different age groups 2–8 years, 1 month to 2 years, Interpretation This first prospective study of glucocorticoid treatment in children with AI and CAH demonstrates that accurate dosing and monitoring from birth results in hydrocortisone doses at the lower end of the recommended dose range and normal growth, without occurrence of adrenal crises.

Congenital adrenal hyperplasia (CAH) is the most common form of adrenal insufficiency in childhood; it requires cortisol replacement therapy with hydrocortisone (HC, synthetic cortisol) from birth and therapy monitoring for successful treatment. In children, the less invasive dried blood spot (DBS) sampling with whole blood including red blood cells (RBCs) provides an advantageous alternative to plasma sampling. Potential differences in binding/association processes between plasma and DBS however need to be considered to correctly interpret DBS measurements for therapy monitoring. While capillary DBS samples would be used in clinical practice, venous cortisol DBS samples from children with adrenal insufficiency were analyzed due to data availability and to directly compare and thus understand potential differences between venous DBS and plasma. A previously published HC plasma pharmacokinetic (PK) model was extended by leveraging these DBS concentrations. In addition to previously characterized binding of cortisol to albumin (linear process) and corticosteroid-binding globulin (CBG; saturable process), DBS data enabled the characterization of a linear cortisol association with RBCs, and thereby providing a quantitative link between DBS and plasma cortisol concentrations. The ratio between the observed cortisol plasma and DBS concentrations varies highly from 2 to 8. Deterministic simulations of the different cortisol binding/association fractions demonstrated that with higher blood cortisol concentrations, saturation of cortisol binding to CBG was observed, leading to an increase in all other cortisol binding fractions. In conclusion, a mathematical PK model was developed which links DBS measurements to plasma exposure and thus allows for quantitative interpretation of measurements of DBS samples.

Context Little is known about the physical health of individuals with 46,XY disorders of sex development (DSD). Objective To assess physical and reported subjective health of individuals with XY DSD. Methods As part of the dsd-LIFE study, patients with an XY DSD condition were analyzed in different diagnosis groups for metabolic parameters, comorbidities, metabolic syndrome, bone outcomes, and reported subjective health. Findings were evaluated by descriptive statistics. Results A total of 222 patients with XY DSD were included with a mean age of 28.8 ± 12.2 years, mean height of 175.3 ± 7.7 cm, mean weight of 74.3 ± 20.0 kg, and mean body mass index of 24.1 ± 6.0 kg/m2. Obesity rate was not increased when descriptively compared with Eurostat data. Fourteen patients had metabolic syndrome (14/175; 8.0%). In descriptive comparison with data from the DECODE study and World Health Organization, subjects fared better in the categories waist circumference, glucose, triglyceride, cholesterol, and high-density lipoprotein. Of participants with available bone health data, 19/122 (15.6%) patients had a Z-score ≤ –2.0 at lumbar spine indicating lowered bone mineral density (BMD). Mostly gonadectomized individuals with complete androgen insensitivity syndrome (CAIS) and no estrogen therapy had lowered BMD at lumbar spine. Individuals with XY DSD performed poorly in the category subjective health in descriptive comparison with Eurostat data. Conclusion Participants reported a lower subjective health status than Eurostat data but their overall metabolic health status was good. Decreased BMD at lumbar spine was especially present in gonadectomized individuals with CAIS and no estrogen therapy.

Summary Background Surgery is performed in many individuals with disorders/differences of sex development (DSD). Irreversibility of some surgical procedures, lack of information about the procedures, and lack of follow-up care for physical and psychological outcomes, lead to wish for more knowledge from both surgeons and patients. After the consensus conference in 2006, multidisciplinary care is provided to a higher degree with psychological support and more restricted surgical procedures. Outcome studies after genital surgery often lack of patient's perspective. Objective To describe surgical procedures in relation to diagnosis, to evaluate the outcomes of surgery through genital examination, and through patient's and observer's satisfaction with the anatomical and functional result after genital surgery. Study design In a cross-sectional clinical study performed in six European countries in 2014/15, we have included 500 participants where surgery was performed, from a total of 1040 adolescents (≥16years) and adults with a DSD. Diagnoses included Turner syndrome (n = 301), mixed gonadal dysgenesis (45,XO/46,XY; n = 45), Klinefelter syndrome (n = 218), XYY (n = 1), 46, XY DSD (n = 222) and 46, XX DSD (n = 253). Study protocol included clinical report files, an optional gynecological or urological examination, patient reported outcomes including received surgical interventions, satisfaction with appearance and function after surgery, and impact of the surgical procedure on life. Results Five hundred participants had received genital or breast surgery, with the highest rate in 46, XY DSD and the lowest in Turner syndrome. Altogether; 240 participants had feminizing surgery, 112 had masculinizing surgery, and 217 underwent gonadectomy. Physicians evaluated anatomical appearance at genital examination as poor in less than 10%. Dissatisfaction with anatomical appearance was reported by 22% of the participants, dissatisfaction with function by 20%. Being (very) dissatisfied with anatomical appearance and function was reported by 13% of the study participants. Most participants reported no impact, or positive impact, of the surgical procedures on their lives, but 29% experienced a negative effect of gonadectomy on their life. Discussion There might be a selection bias and/or a recall bias for participating in our studies. Due to poor data quality about surgical procedures performed in the past, we also relied on participants memory about surgical procedures in their past. Ideally, patient reported outcomes should be evaluated both before and after surgical procedures. Conclusion A vast majority are satisfied with appearance and function, but still genital or breast surgery have a long-lasting effect on patient's life. Self-reported satisfaction is usually lower than the observer's evaluation regarding both appearance and function. Download : Download high-res image (217KB) Download : Download full-size image Summary Figure . Satisfaction with anatomy and function after genital surgery in individuals with DSD (appearance: n = 244; function: n = 257) (n = total number of participants).

Previous studies have reported a shift in the timing of sleep during adolescence toward a later time. To date, it is unclear whether hormonal changes during puberty might contribute to this change in sleeping behavior. We systematically assessed pubertal development and sleep timing in a cross-sectional case-control study in girls with precocious (n = 42) and boys with delayed pubertal development (n = 19). We used the Munich ChronoType Questionnaire and the Children&rsquo, s ChronoType Questionnaire to assess sleep timing in patients and age- and sex-matched controls (n = 309) and used the midpoint of sleep on free days, corrected for potential sleep debt accumulated during the school week, as a marker for sleep timing. Compared to the controls, girls with central precocious puberty showed a delay in sleep timing of 54 min, and girls with premature pubarche slept on average 30 min later. Male adolescents with delayed pubertal development showed an average sleep midpoint that was 40 min earlier compared to the control group. The results of this pilot study suggest an association between pubertal onset and shifts in sleep timing, which is a novel finding in human sleep behavior. Prospective studies in larger cohorts will be needed to examine the robustness and generalizability of the findings.

Context: Accurate hydrocortisone dosing in children with adrenal insufficiency is important to avoid the risks of over and under treatment including iatrogenic Cushing’s syndrome and adrenal crisis. Objective: To establish a population pharmacokinetic model of hydrocortisone in children and use this to refine hydrocortisone replacement regimens. Design and methods: Pharmacokinetic study of hydrocortisone granules, available in 0.5, 1, 2 and 5 mg dose strengths, in 24 children with adrenal insufficiency aged 2 weeks to 6 years. Cortisol concentrations quantified by LC-MS/MS were used to refine an adult pharmacokinetic model to a paediatric population model which was then used to simulate seven different hydrocortisone treatment regimens. Results: Pre-dose cortisol levels were undetectable in 54% of the 24 children. The developed pharmacokinetic model had good predictive performance. Simulations for the seven treatment regimens using either three- or four-times daily dosing showed treatment regimens delivered an AUC0-24h within the 90% reference range for healthy children except in neonates where two regimens had an AUC below the 5th percentile. Cortisol concentrations at individual time points in the 24 h were outside the 90% reference range for healthy individuals in 50%, 55–65% and 70–75% for children, infants and neonates, respectively, with low cortisol levels being most prevalent. Conclusions: Current paediatric hydrocortisone treatment regimens based on either three- or four-times daily administration replicate cortisol exposure based on AUC0-24h, but the majority of cortisol levels are above or below physiological cortisol levels with low levels very common before the next dose.

Objectives There is no licensed, dose-appropriate formulation of hydrocortisone for children with adrenal insufficiency (AI) and patients rely on compounded adult medication. The aim of this study was to evaluate the absorption, palatability and safety of Infacort®, an immediate-release, granule formulation of hydrocortisone with taste masking. Study design Single site with satellites attended by a “flying” doctor from investigator site. Open-label, single-dose study in three consecutive child cohorts (n=24) with AI; Cohort 1, children aged 2 to Au: the age ranges quoted are slightly different in each of the abstract, main text, Table 1 and Supplemental table. These have now been unified as shown here. . Methods Fasted children were given a single dose of Infacort® as dry granules administered directly from a capsule or spoon followed by a drink. The primary endpoint was the maximum serum cortisol concentration up to 240 minutes after Infacort® administration. Secondary endpoints were palatability and adverse events (AEs). Results All children showed an increase in cortisol above baseline after Infacort® (p

Neonatal diabetes may be of transient or permanent nature. While certain mutations in ABCC8 and KCNJ11 genes coding the ATP-dependent potassium channel (KATP) cause both transient (TNDM) and permanent neonatal diabetes (PNDM), chromosomal abnormalities in 6q24 are the most frequent cause for TNDM.

Objectives Due to the lack of paediatric-licensed formulations, children are often treated with individualized pharmacy-compounded adult medication. An international web-based survey about the types of medication in children with adrenal insufficiency (AI) revealed that the majority of paediatric physicians are using pharmacy-compounded medication to treat children with AI. Observations of loss of therapy control in children with congenital adrenal hyperplasia with compounded hydrocortisone capsules and regained control after prescribing a new hydrocortisone batch led to this ‘real world’ evaluation of pharmacy-compounded paediatric hydrocortisone capsules. Methods Capsule samples were collected randomly from volunteering parents of treated children suffering from congenital adrenal hyperplasia from all over Germany. Analysis of net mass and hydrocortisone content by high-performance liquid chromatography with ultraviolet (HPLC-UV) detection method was performed based on the European Pharmacopeia. Results In a total of 61 batches that were sent, 5 batches could not be analysed because of missing dose information, insufficient number of capsules or were not possible to be evaluated. Fifty-six batches containing 1125 capsules were evaluated. 21.4% of the batches revealed insufficiency in uniformity of net mass or drug content and additional 3.6% failed because they did not contain the labelled drug. Conclusions Compounded medication is a possible cause of variation of steroid doses in children with adrenal insufficiency or congenital adrenal hyperplasia, putting these vulnerable patients at risk of poor disease control and adrenal crisis. These data may apply to other individualized compounded oral medication as well, emphasizing the need for development of licensed paediatric formulations approved by regulatory authorities.

BackgroundPatients with congenital adrenal hyperplasia (CAH) have low to no biosynthesis of cortisol and require lifelong cortisol replacement. Optimisation of hydrocortisone (HC, synthetic cortisol) therapy in this population is important, since too low or high cortisol concentrations increase the risk of adrenal crisis or Cushing’s syndrome1. HC has nonlinear pharmacokinetics (PK) caused by saturable binding to corticosteroid binding globulin (CBG)2. The objective of this analysis was to extend an established paediatric HC PK-model3 with dried blood spot (DBS) data in order to further characterise the binding behaviour of HC in children.MethodsA semi-mechanistic adult PK model for a novel HC formulation4 has previously been reduced to a paediatric model using sparse plasma samples from a phase III study in 24 patients with adrenal insufficiency5. Plasma and DBS concentrations of cortisol were collected and additional DBS HC concentrations were obtained from a follow-up study. The relation between plasma and DBS samples was characterised by a graphical evaluation, after which nonlinear mixed-effects modelling was applied using NONMEM 7.4.ResultsPlasma concentrations of cortisol were substantially higher than the corresponding DBS concentrations. The plasma/DBS ratio ranged between 2 to 8 within and between children, while the relation between the cortisol DBS concentrations and cortisol plasma concentrations showed nonlinear behaviour mirroring the nonlinear binding kinetics to CBG.ConclusionsOur graphical analysis identified substantial differences and high inter- and intraindividual variabilities between plasma and DBS samples. A nonlinear mixed-effects model is being set up to quantify these findings and allow for further prediction of HC exposure. Afterwards, effect biomarkers can be included in order to evaluate cortisol replacement therapy and to optimise the HC treatment in paediatric patients.ReferencesSpeiser PW, et al. J Clin Endocrinol Metab 2010;95(9):4133–4160.Lentjes EG, WM, et al:J Clin Endocrinol Metab. 1999;84(2):682–687.Melin J:Dissertation 2017.Melin J, et al:Clin Pharmacokinet. 2018;57(4):515–527.Neumann U. et al:Clin Endocrinol. 2018;88(1):21–29.Disclosure(s)Nothing to disclose

BACKGROUND: Epidemiological data have shown long-term health adversity in low birth weight subjects, especially concerning the metabolic syndrome and 'diabesity' risk. Alterations in adult food intake have been suggested to be causally involved. Responsible mechanisms remain unclear. METHODS AND FINDINGS: By rearing in normal (NL) vs. small litters (SL), small-for-gestational-age (SGA) rats were neonatally exposed to either normal (SGA-in-NL) or over-feeding (SGA-in-SL), and followed up into late adult age as compared to normally reared appropriate-for-gestational-age control rats (AGA-in-NL). SGA-in-SL rats displayed rapid neonatal weight gain within one week after birth, while SGA-in-NL growth caught up only at juvenile age (day 60), as compared to AGA-in-NL controls. In adulthood, an increase in lipids, leptin, insulin, insulin/glucose-ratio (all p

Bei den wesentlichen Aussagen des Marktphasenschemas handelt es sich teilweise um nicht direkt mesbare Merkmale. Operationalisierung ist der Prozes der Mesbarmachung solcher Merkmale. Dazu bedient man sich direkt mesbarer Ersatzgrosen fur das Phanomen, auch Indikatoren genannt. “Ziel einer Operationalisierung ist, den Begriffen einer Wissenschaft grosere Prazision zu geben, sie somit empirisch gehaltvoller zu machen.”1

Im vorangegangenen Kapitel sind die wesentlichen Aussagen des Marktphasenschemas operationalisiert worden. Die fur die Datensammlung verwendeten Quellen wurden dabei teilweise bereits erwahnt. Trotzdem werden zu Beginn jedes Teilkapitels die verwendeten Quellen sowie die Vorgehensweise bei der Messung und Auswertung noch einmal ausfuhrlich dargestellt. Daran anschliesend werden die Ergebnisse zu den untersuchten Aussagen prasentiert und mit den von Heus prognostizierten Entwicklungen verglichen. Dabei soll sich herausstellen, ob die Heus’schen Hypothesen auf dem Markt fur Elektrische Haushaltsgerate zutreffen oder nicht.

Das von Ernst Heus entwickelte Marktphasenschema1 ist ein Ansatz der Wettbewerbstheorie, der auf die Vorstellung zuruckgreift, das ein Markt — wie ein Produkt — typische Phasen durchlauft, von denen ein wesentlicher Einflus auf die Marktstruktur und das Marktverhalten ausgeubt wird.2 Heus Verdienst ist es, durch die Phasenbetrachtung ein dynamisches Element in die Markttheorie eingefuhrt zu haben.3