Search

Abstract Background ROS1 fusion is an infrequent, but attractive target for therapy in patients with metastatic non- small-cell lung cancer. In studies on mainly late-stage disease, the prevalence of ROS1 fusions is about 1–3%. In early-stage lung cancer ROS1 might also provide a fruitful target for neoadjuvant or adjuvant therapy. In the present study, we investigated the prevalence of ROS1 fusion in a Norwegian cohort of early-stage lung cancer. We also explored whether positive ROS1 immunohistochemical (IHC) stain was associated with certain mutations, clinical characteristics and outcomes. Methods The study was performed using biobank material from 921 lung cancer patients including 542 patients with adenocarcinoma surgically resected during 2006–2018. Initially, we screened the samples with two different IHC clones (D4D6 and SP384) targeting ROS1. All samples that showed more than weak or focal staining, as well as a subgroup of negative samples, were analyzed with ROS1 fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS) with a comprehensive NGS DNA and RNA panel. Positive ROS1-fusion was defined as those samples positive in at least two of the three methods (IHC, FISH, NGS). Results Fifty cases were IHC positive. Of these, three samples were both NGS and FISH-positive and considered positive for ROS1 fusion. Two more samples were FISH positive only, and whilst IHC and NGS were negative. These were also negative with Reverse Transcription quantitative real time Polymerase Chain Reaction (RT-qPCR). The prevalence of ROS1 fusion in adenocarcinomas was 0.6%. All cases with ROS1 fusion had TP53 mutations. IHC-positivity was associated with adenocarcinoma. Among SP384-IHC positive cases we also found an association with never smoking status. There was no association between positive IHC and overall survival, time to relapse, age, stage, sex or pack-year of smoking. Conclusions ROS1 seems to be less frequent in early-stage disease than in advanced stages. IHC is a sensitive, but less specific method and the results need to be confirmed with another method like FISH or NGS.

Abstract Introduction The Bergen 4-Day Treatment (B4DT) is a concentrated treatment with individually tailored exposure exercises. The format has shown promising results in the treatment of panic disorder. Aim The aim of the current study was to investigate the effectiveness of the B4DT in a large sample in a rural clinical setting. Method Fifty-eight patients with panic disorder were consecutively included using an open trial design. The primary outcome measure was the Panic Disorder Severity Scale. The Generalized Anxiety Disorder-7 and the Patient Health Questionnaire-9 were used as secondary outcome measures. Assessments were conducted at pretreatment, posttreatment, and 3-month follow-up. Treatment satisfaction was measured at posttreatment using the Client Satisfaction Questionnaire-8. Results There was a significant reduction in symptoms of panic disorder from pre- to posttreatment (d = 3.36) and from pretreatment to follow-up (d = 3.63). At posttreatment and follow-up, 72.4% and 81.0% of patients, respectively, were classified as in remission. Patients reported high treatment satisfaction, and there were significant reductions in symptoms of generalized anxiety and depression. Conclusion The results from the current study replicated the findings from previous studies using a larger sample size. The findings indicate that the B4DT is a promising treatment format for panic disorder. The study also demonstrated that the treatment format can be successfully implemented in new rural clinics.

Abstract For many species, the ability to rapidly adapt to changes in seasonality is essential for long‐term survival. In the Arctic, seasonal moulting is a key life‐history event that provides year‐round camouflage and thermal protection. However, increased climatic variability of seasonal events can lead to phenological mismatch. In this study, we investigated whether winter‐white (white morph) and winter‐brown (blue morph) Arctic foxes (Vulpes lagopus) could adjust their winter‐to‐summer moult to match local environmental conditions. We used camera trap images spanning an eight‐year period to quantify the timing and rate of fur change in a polymorphic subpopulation in south‐central Norway. Seasonal snow cover duration and temperature governed the phenology of the spring moult. We observed a later onset and longer moulting duration with decreasing temperature and longer snow season. Additionally, white foxes moulted earlier than blue in years with shorter periods of snow cover and warmer temperatures. These results suggest that phenotypic plasticity allows Arctic foxes to modulate the timing and rate of their spring moult as snow conditions and temperatures fluctuate. With the Arctic warming at an unprecedented rate, understanding the capacity of polar species to physiologically adapt to a changing environment is urgently needed in order to develop adaptive conservation efforts. Moreover, we provide the first evidence for variations in the moulting phenology of blue and white Arctic foxes. Our study underlines the different intraspecific selective pressures that can exist in populations where several morphs co‐occur, and illustrates the importance of integrating morph‐based differences in future management strategies of such polymorphic species.

Abstract Clearance of neurotoxic brain proteins via cerebrospinal fluid (CSF) to blood has recently emerged to be crucial, and plasma biomarkers of neurodegeneration were newly introduced to predict neurological disease. This study examines in 106 individuals with neurological disorders associations between plasma biomarkers [40 and 42 amino acid-long amyloid-β (Aβ40 and Aβ42), total-tau, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL)] and magnetic resonance imaging measures of CSF-mediated clearance from brain via extra-vascular pathways (proxy of glymphatic function) and CSF-to-blood clearance variables from pharmacokinetic modeling (proxy of meningeal lymphatic egress). We also examine how biomarkers vary during daytime and associate with subjective sleep quality. Plasma concentrations of neurodegeneration markers associate with indices of glymphatic and meningeal lymphatic functions in individual- and disease-specific manners, vary during daytime, but are unaffected by sleep quality. The results suggest that plasma concentrations of neurodegeneration biomarkers associate with measures of glymphatic and meningeal lymphatic function.

Abstract Background Despite greatly renewed interest concerning meningeal lymphatic function over recent years, the lymphatic structures of human dura mater have been less characterized. The available information derives exclusively from autopsy specimens. This study addressed methodological aspects of immunohistochemistry for visualization and characterization of lymphatic vessels in the dura of patients. Methods Dura biopsies were obtained from the right frontal region of the patients with idiopathic normal pressure hydrocephalus (iNPH) who underwent shunt surgery as part of treatment. The dura specimens were prepared using three different methods: Paraformaldehyde (PFA) 4% (Method #1), paraformaldehyde (PFA) 0.5% (Method #2), and freeze-fixation (Method #3). They were further examined with immunohistochemistry using the lymphatic cell marker lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), and as validation marker we used podoplanin (PDPN). Results The study included 30 iNPH patients who underwent shunt surgery. The dura specimens were obtained average 16.1 ± 4.5 mm lateral to the superior sagittal sinus in the right frontal region (about 12 cm posterior to glabella). While lymphatic structures were seen in 0/7 patients using Method #1, it was found in 4/6 subjects (67%) with Method #2, while in 16/17 subjects (94%) using Method #3. To this end, we characterized three types of meningeal lymphatic vessels: (1) Lymphatic vessels in intimate contact with blood vessels. (2) Lymphatic vessels without nearby blood vessels. (3) Clusters of LYVE-1-expressing cells interspersed with blood vessels. In general, highest density of lymphatic vessels were observed towards the arachnoid membrane rather than towards the skull. Conclusions The visualization of meningeal lymphatic vessels in humans seems to be highly sensitive to the tissue processing method. Our observations disclosed most abundant lymphatic vessels towards the arachnoid membrane, and were seen either in close association with blood vessels or remote from blood vessels.

Human MRI data shows that parasagittal dura volume may not play a major role in cerebrospinal fluid clearance but could instead serve as a neuro-immune interface.

Abstract Background In Scandinavia, various public reforms are initiated to enhance trust in the healthcare services and the public sector in general. This study explores experiences from a two-step service innovation project in municipal home care in Norway, coined as the Trust Model (TM), aiming at developing an alternative to the purchaser-provider split (PPS) and enhancing employee motivation, user satisfaction, and citizen trust. The PPS has been the prevalent model in Norway since the 1990s. There is little empirical research on trust-based alternatives to the PPS in healthcare. The overall objectives of this study were to explore facilitators and barriers to trust-based service innovation of municipal homecare and to develop a framework for how to support the implementation of the TM. Methods The TM elements were developed through a comprehensive participatory process, resulting in the decision to organize the home care service in small, self-managed and multidisciplinary teams, and trusting the teams with full responsibility for care decisions and delivery within a limited area. Through a longitudinal mixed methods case study design a) patients’ expressed values and b) factors facilitating or preventing the service innovation process were explored through two iterations. The first included three city districts, three teams and 80 patients. The second included four districts, eight teams and 160 patients. Results The patient survey showed patients valued and trusted the service. The team member survey showed increased motivation for work aligned with TM principles. Both quantitative and qualitative methods revealed a series of facilitators and barriers to the innovation process on different organizational levels (teams, team leaders, system). The key message arising from the two iterations is to keep patients’ values in the centre and recognize the multilevelled organizational complexity of successful trust-based innovation in homecare. Synthesizing the results, a framework for how to support trust-based service innovation was constructed. Conclusions Trust-based innovation of municipal homecare is feasible. The proposed framework may serve as a tool when planning trust-based innovation, and as a checklist for implementation and improvement strategies. Further research is needed to explore the validity of the framework and its replicability in other areas of healthcare.

Abstract Background Resectable adenocarcinomas in the pancreatic head, by definition "periampullary", originate from ampullary, duodenal, biliary, or ductal pancreatic epithelium. Typically, periampullary adenocarcinomas have either intestinal or pancreatobiliary type of differentiation, and the type of differentiation might be prognostically more important than the anatomic site of origin. The aim of the study was to determine whether the histologic type of differentiation is an independent prognostic factor in periampullary adenocarcinoma, and whether tumour origin predicts the prognosis in pancreatobiliary type carcinomas independently of resection margin involvement, tumour size, nodal involvement, perineural and vascular infiltration, and degree of differentiation. Methods Histopathologic variables in 114 consecutively resected periampullary adenocarcinomas of pancreatobiliary (n = 67) and intestinal (n = 47) type differentiation were evaluated using a standardized, systematic protocol for evaluation of the resected specimen (study group). Histologic type of differentiation and tumour origin were compared as predictors of survival, and the results were validated by comparison with a historical control group consisting of 99 consecutive pancreaticoduodenectomies performed before standardization of histopathologic evaluation. Associations between histopathologic variables were evaluated by Chi-square and Mann-Whitney tests. Survival was estimated by the Kaplan-Meier method, comparing curves using log-rank test, and by univariate and multivariable Cox regression analysis. Results Both in the study group (n = 114) and in the historical control group (n = 99), the histologic type of differentiation independently predicted survival, while tumour origin predicted survival only in univariate analysis. Independent adverse predictors of survival in the study group were pancreatobiliary type differentiation (p < 0.001; HR 3.1; CI 1.8–5.1), regional lymph node involvement (p < 0.001; HR 2.5; CI 1.5–4.4), vessel involvement (p = 0.012; HR 1.9; CI 1.2–3.1), and increasing tumour diameter (measured in cm, p = 0.011; HR 1.3; CI 1.1–1.5). For pancreatobiliary differentiated adenocarcinomas (n = 67), lymph node status, vessel involvement, and tumour diameter remained independent prognostic factors, while tumour origin did not independently predict the prognosis due to significant association with tumour size (p < 0.001) and lymph node involvement (p = 0.004). Conclusion Pancreatobiliary versus intestinal type of differentiation independently predicts poor prognosis after pancreaticoduodenectomy for periampullary adenocarcinoma. Lymph node involvement, vessel infiltration, and increasing tumour diameter are adverse predictors of survival in tumours with pancreatobiliary differentiation.

Abstract Background The retroperitoneal margin is frequently microscopically tumour positive in non-curative periampullary adenocarcinoma resections. This margin should be evaluated by serial perpendicular sectioning. The aim of the study was to determine whether retroperitoneal margin involvement independently predicts survival after pancreaticoduodenectomy within a framework of standardized assessment of the resected specimens. Methods 114 consecutive macroscopically margin-free periampullary adenocarcinomas were examined according to a prospective standardized protocol for histopathologic evaluation. The retroperitoneal margin was assessed by serial perpendicular sectioning. The periampullary cancer origin (pancreas, ampulla, distal bile duct or duodenum) was registered prospectively and reevaluated retrospectively. Associations between histopathologic factors were evaluated by Chi-square test, Fisher's exact test, Kruskal-Wallis test, and Mann-Whitney test, as appropriate. Survival curves were calculated by the Kaplan-Meier method and compared using the log-rank test. Associations between histopathologic factors and survival were also evaluated by unadjusted and adjusted Cox regression analysis, including stepwise variable selection, in order to identify factors that independently predict a poor prognosis after periampullary adenocarcinoma resections. Results Microscopic resection margin involvement (R1 resection) was present in 40 tumours, of which 32 involved the retroperitoneal margin. Involvement of the retroperitoneal margin independently predicted a poor prognosis (p = 0.010; HR 1.89; CI 1.16–3.08) after presumed curative (R0 and R1) resection. In microscopically curative (R0) resections (n = 74), pancreatic tumour origin was the only factor that independently predicted a poor prognosis (p < 0.001; HR 4.71 for pancreatic versus ampullary; CI 2.13–10.4). Conclusion Serial perpendicular sectioning of the retroperitoneal resection margin demonstrates that tumour involvement of this margin independently predicts survival after pancreaticoduodenectomy for adenocarcinoma. Periampullary tumour origin is the only histopathologic factor that independently predicts survival in microscopically curative (R0) resections.

At least one third of all U.S. college students don't get a degree, even six years after they enroll. Earlier research focusing on trends through 1990 found broad declines in college graduation rates, especially among men attending less-selective four-year schools. Since then, however, the picture of college enrollment has changed dramatically, with increases in both high-school graduation and college matriculation rates. Have completion rates changed as well? To find out, the authors analyzed federal education and Census data and found that rates of college completion have gone up since 1990, at a broad mix of institution types and among both men and women. This trend is confirmed in federal data, the Census, and registrar data from 10 public universities. What's driving this growth? The authors looked at student background and academic preparation, as well as institutional practices like support-service spending, and find that none of these potential factors explain the changes. But one trend is clear across all the datasets: compared to decades past, college students have been earning better grades in recent years, and better college grades are strongly associated with higher rates of graduation. The authors explore a range of factors that could influence student performance, such as high-school preparation and rates of labor-force participation in college and find that these would predict students to be less likely to graduate, not more. While earning a degree is something to be lauded, evidence of grade inflation raises important questions about the meaning of some college degrees. And with growing uncertainty about the relative return on investment in terms of both time and tuition, both students and institutions should take a hard look at the ultimate value of their efforts.

Age-related macular degeneration (AMD) is the most frequent cause of blindness in developed countries. The replacement of dysfunctional human retinal pigment epithelium (hRPE) cells by the transplantation of in vitro-cultivated hRPE cells to the affected area emerges as a feasible strategy for regenerative therapy. Synthetic biomimetic membranes arise as powerful hRPE cell carriers, but as biodegradability is a requirement, it also poses a challenge due to its limited durability. hRPE cells exhibit several characteristics that putatively respond to the type of membrane carrier, and they can be used as biomarkers to evaluate and further optimize such membranes. Here, we analyze the pigmentation, transepithelial resistance, genome integrity, and maturation markers of hRPE cells plated on commercial polycarbonate (PC) versus in-house electrospun polylactide-based (PLA) membranes, both enabling separate apical/basolateral compartments. Our results show that PLA is superior to PC-based membranes for the cultivation of hRPEs, and the BEST1/RPE65 maturation markers emerge as the best biomarkers for addressing the quality of hRPE cultivated in vitro. The stability of the cultures was observed to be affected by PLA aging, which is an effect that could be partially palliated by the coating of the PLA membranes.

IntroductionRecovery colleges (RCs) are learning environments, first established in the UK, based on principles that support positive life changes and reduce stigma related to challenges with mental health and substance use problems. RCs offer courses based on co-production processes and are designed and delivered jointly by individuals with lived experience and professional experts. The courses are open to anyone, attracting people with a variety of life experiences. RCs are non-clinical environments that provide individuals with the identities of students and/or trainers as autonomous and independent agents. In this paper, we investigate experiences of being a part of a RC in Norway, either as a student and/or as a course trainer with lived experiences of mental health or substance use challenges. We ask the following research question: What kinds of personal and social processes are enabled by being part of a recovery college from the perspective of persons with experience-based competence?Materials and methodsThe study is qualitative and explorative based on 11 individual (N = 11) and two focus group interviews (N = 8). Participants were recruited from two of the first RCs in Norway between August 2021 and January 2022.ResultsStudy participants describe how their involvement in a RC provided them with opportunities to assume new positions in their recovery process, both related to former institutional identities given in the course of treatment and related to the way they see themselves as people struggling with mental health and substances use challenges. Attending a RC represented significant transitions (1) from an institutional position as “sick” or as “what’s on the paper” into a position as “a whole person”; (2) from being in in a position as a recipient of care to the position as actively responsible for life changes; (3) from seeing themselves as worthless to seeing themselves as persons with resources; (4) from being alone to being part of a fellowship. Participants describe being part of a RC as an invaluable addition to other kind of support or help.DiscussionIt is important to provide alternative arenas like RC for facilitating work with life changes, as an invaluable addition to regular services.

Background and purpose: Previous experimental studies have shown that meningeal lymphatic vessels are located primarily along the walls of the dural sinus veins. Whether they are more widespread throughout human dura mater has presently not been characterized. The present study explored in humans whether meningeal lymphatic vessels may be identified remote from the sinus veins and whether they differ in the various location of dura mater.Methods: We included 15 patients who underwent neurosurgery, in whom dura mater was removed as part of the planned procedure. Tissue was prepared for immunohistochemistry using the lymphatic endothelial cell markers lymphatic vessel endothelial hyaluronan receptor 1 protein (LYVE-1), podoplanin and vascular endothelial growth factor receptor 3 (VEGFR3).Results: Lymphatic endothelial cell positive cells were found in dura mater at the posterior fossa (n = 8), temporal skull base (n = 5), frontal convexity (n = 1), and cranio-cervical junction (n = 1). They were most commonly seen remote from blood vessels, but also occurred along blood vessels, and seemed to be most abundant at the skull base.Conclusion: The present observations show that human lymphatic vessels are widespread in dura mater, not solely lining the dural sinuses.

Abstract Background The quality of nursing care in different healthcare contexts can be associated with the level of available nursing competence. Physical assessment skills are vital in nurses' assessment of patient care needs. However, in nursing education, using physical assessment skills is challenging for nursing students who struggle to apply these skills comprehensively in a clinical rotation. Therefore, this study explores changes in nursing competence, factors associated with changes after clinical rotations, and whether a Suite of Mobile Learning Tools supports changes in confident use of basic physical assessment skills. Methods A quantitative cohort study with an explorative pre-and post-test design. During autumn 2019 and spring 2020, 72 s-year nursing students and 99 third-year students participated in the study. The Nurse Professional Competence scale short form was used to investigate students’ self-reported changes in nursing competence, and a study-specific questionnaire was used to investigate students’ confidence concerning performing physical assessments. The students voluntarily used the Suite of Mobile Learning Tools for the learning of physical assessment. Linear regression analysis was used to identify factors associated with changes in nursing competence after clinical rotation. The STROBE guidelines for cohort studies were followed for study reporting. Results After the clinical rotation, both student groups reported changes in nursing competence and confidence in performing physical assessment skills, with statistically significant moderate or large changes in all areas. The Suite of Mobile Learning Tools was evaluated as being useful for learning physical assessment. The regression analysis showed that confidence in performing physical assessment skills, the usefulness of the Suite of Mobile Learning Tools, and a higher nursing competence at the start of clinical rotation were positively associated with overall nursing competence. Conclusion Basic physical assessment skills are an important component of nursing competence and can be considered one of the pillars of person-centered care, as proposed by the Fundamentals of Care framework. Spaced repetition and access to digital resources are suggested pedagogical approaches to enhance student confidence in the use of assessment skills within academic and clinical contexts.

Retrogressive development of landslides in highly sensitive clays (quick clays) may extend several hundred metres upslope from an initial landslide, and liquified slide-debris may impact buildings or infrastructure in the run-out zone. By installing wells filled with potassium chloride (KCl) in quick clays, the salt migrates into the surrounding clay and increases its remolded shear strength, reducing its sensitivity. The salt-stabilized, nonquick clay volume may act as a barrier preventing backward retrogression, thereby contributing to reducing both the area susceptible for being involved in a quick-clay landslide, and the area of the run-out zone. Installation procedures and design guidelines for salt stabilization are examined herein. Installation procedures generating temporary, very small excess pore-water pressures were tested at National Geo-Test Site Tiller- Flotten. Although the benefit-to-cost ratios related to these procedures are small compared to conventional landslide mitigation measures, reducing the installation costs to less than 30 USD per m well and increasing the center distance between the wells may justify salt-stabilization as a landslide mitigation measure. This paper describes experience from testing safe installation procedures, evaluations of cost-benefit and environmental impact, and proposed design guidelines, introducing KCl as an alternative to conventional landslide mitigation-measures in slopes with highly sensitive quick-clay deposits. Key words: climate-gas emissions, geochemistry, ground improvement, installation effects, potassium chloride, quick clay Le developpement retroactif des glissements de terrain dans les argiles extra sensibles (argiles rapides) peut s'etendre sur plusieurs centaines de metres en amont d'un glissement initial, et les debris de glissement liquefies peuvent avoir un impact sur les batiments ou les infrastructures dans la zone de ruissellement. En installant des puits remplis de chlorure de potassium dans des argiles rapides, le sel migre dans l'argile environnante et augmente sa resistance au cisaillement remodelee, ce qui reduit sa sensibilite. Le volume d'argile non rapide stabilise par le sel peut agir comme une barriere empechant la retrogression, contribuant ainsi a reduire a la fois la zone susceptible d'etre impliquee dans un glissement de terrain a argile rapide et la zone de ruissellement. Les procedures d'installation et les directives de conception pour la stabilisation au sel sont examinees dans le present document. Des procedures d'installation generant de tres faibles surpressions temporaires de l'eau interstitielle ont ete testees sur le site national de geotest de Tiller-Flotten. Bien que les rapports avantages-couts lies a ces procedures soient faibles par rapport aux mesures conventionnelles d'attenuation des glissements de terrain, la reduction des couts d'installation a moins de 30 USD par m de puits et l'augmentation de la distance centrale entre les puits peuvent justifier la stabilisation saline comme mesure d'attenuation des glissements de terrain. Cet article decrit l'experience acquise lors de la mise a l'essai de procedures d'installation sures, l'evaluation des couts-avantages et de l'impact sur l'environnement, ainsi que les directives de conception proposees. Il presente le chlorure de potassium comme une alternative aux mesures conventionnelles d'attenuation des glissements de terrain dans les pentes presentant des depots d'argile rapide tres sensibles. [Traduit par la Redaction] Mots-cles : emissions de gaz a effet de serre, geochimie, amelioration du sol, effets d'installation, chlorure de potassium, argile rapide, Introduction Landslides in areas with highly sensitive clays, herein termed quick clays, may penetrate far into slopes, have long run-out and be catastrophic, as shown by the recent quick-clay landslide [...]

Purpose: Due to environmental concerns, there is a demand to reduce the use of peat as a growing medium for horticultural crops. Simultaneously, there is an interest to recycle organic waste materials in the form of compost. This study aimed to document effects on growth, yield, and fruit quality of tomato plants when cultivated in a sewage digestate-based compost in a subirrigation container system. Materials and methods: The compost used in this experiment consisted of 30% hygienised sewage digestate from biogas extraction and 70% garden waste. The treatments were 100% compost, a peat mix and mixtures of the two in 25/75, 50/50 and 75/25 ratios. Results and conclusion: Considering the contrast in chemical and physical properties of the treatments, variations in growth, yield and quality were expected. The plants differed in leaf area and number of leaves, but there were no differences in yield or quality of the tomato fruits. It is assumed that this is in great part due to the remediating effects of subirrigation with an ideal nutrient solution, and the use of pre-established plants. Further research should focus on benefits of this cultivation system for use in sustainable horticulture in combination with recycled organic waste.

For flere formål er det nyttig å ha en modell for verdsetting av hele den norske boligmassen. Den hedoniske boligverdsettingsmodellen som i dag benyttes av Skatteetaten, har vist seg å være lite robust ved endringer av kommunegrenser. Her undersøker vi hvordan verdsettelse av boliger i større grad kan frigjøres fra kommunegrensene. Ved å benytte mer finmasket geografisk informasjon er det også mulig å forbedre treffsikkerheten til modellen. Vi utarbeider en modell basert på grunnkretser, og en maskinlæringsalgoritme for å gruppere grunnkretsene til grupper med tilstrekkelig antall observasjoner. De 14 000 grunnkretsene i Norge deles opp i ca. 1 200 grupperinger, separat for bygningstype. For hver kombinasjon av geografisk område og bygningstype kjøres en separat hedonisk regresjon for å predikere boligverdi. Den grunnleggende avveiningen ved aggregering av grunnkretser er at man ønsker små, homogene områder, samtidig som man er avhengig av et visst antall omsetninger i den hedoniske regresjonen. Det resulterer i mange, geografisk små grupper i sentrale strøk, og geografisk større grupper i mindre sentrale strøk. Slik utnyttes den store mengden informasjon i byer til bedre å predikere lokale prisnivåer. Vi estimerer den nye modellen for Oslo, Hedmark og Møre og Romsdal, tre regioner med forskjellige markedskarakteristikker. Grunnkretsmodellen gir tydelige forbedringer i prediksjonskraften for beregnet boligverdi sammenlignet med eksisterende modell. Dette gjelder for alle tre regioner, og for fire forskjellige mål på prediksjonskraft. I tillegg forbedrer grunnkretsmodellen prediksjonen av boligverdi for dyre boliger i Oslo kraftig. Dette har vært en kjent svakhet ved den eksisterende modellen. Resultatene for den nye modellen er svært like for 2019 og 2020, noe som tyder på at endringer i kommunestrukturen har liten effekt på modellen, og at den er relativt stabil over tid. Vi diskuterer også kort andre metoder som kan brukes for bedre å utnytte informasjonen som er tilgjengelig i dagens data.