Browsing by Subject "STANDARDS"

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  • Kallio, Galina (2020)
    Questions of value are central to understanding alternative practices of food exchange. This study introduces a practice-based approach to value that challenges the dominant views, which capture value as either an input for or an outcome of practices of exchange (value as values, standards, or prices). Building on a longitudinal ethnographic study on food collectives, I show how value, rather than residing in something that people share, or in something that objects have, is an ideal target that continuously unfolds and evolves in action. I found that people organized their food collectives around pursuing three kinds of value-ideals, namely good food, good price and good community. These value-ideals became reproduced in food collectives through what I identified as valuing modes, by which people evaluated the goodness of food, prices and community. My analysis revealed that, while participating in food collectives in order to pursue their value-ideals, people were likely to have differing reasons for pursuing them and tended to attach different meanings to the same value-ideal. I argue that understanding how value as an ideal target is reproduced through assessing and assigning value (valuing modes) is essential in further explorations of the formation of value and in better understanding the dynamics of organizing alternative practices of food exchange.
  • Izzo, Massimiliano; Mortola, Francesco; Arnulfo, Gabriele; Fato, Marco M.; Varesio, Luigi (2014)
    Motivation: Molecular biology laboratories require extensive metadata to improve data collection and analysis. The heterogeneity of the collected metadata grows as research is evolving in to international multi-disciplinary collaborations and increasing data sharing among institutions. Single standardization is not feasible and it becomes crucial to develop digital repositories with flexible and extensible data models, as in the case of modern integrated biobanks management. Results: We developed a novel data model in JSON format to describe heterogeneous data in a generic biomedical science scenario. The model is built on two hierarchical entities: processes and events, roughly corresponding to research studies and analysis steps within a single study. A number of sequential events can be grouped in a process building up a hierarchical structure to track patient and sample history. Each event can produce new data. Data is described by a set of user-defined metadata, and may have one or more associated files. We integrated the model in a web based digital repository with a data grid storage to manage large data sets located in geographically distinct areas. We built a graphical interface that allows authorized users to define new data types dynamically, according to their requirements. Operators compose queries on metadata fields using a flexible search interface and run them on the database and on the grid. We applied the digital repository to the integrated management of samples, patients and medical history in the BIT-Gaslini biobank. The platform currently manages 1800 samples of over 900 patients. Microarray data from 150 analyses are stored on the grid storage and replicated on two physical resources for preservation. The system is equipped with data integration capabilities with other biobanks for worldwide information sharing. Conclusions: Our data model enables users to continuously define flexible, ad hoc, and loosely structured metadata, for information sharing in specific research projects and purposes. This approach can improve sensitively interdisciplinary research collaboration and allows to track patients' clinical records, sample management information, and genomic data. The web interface allows the operators to easily manage, query, and annotate the files, without dealing with the technicalities of the data grid.
  • Cai, Runlong; Attoui, Michel; Jiang, Jingkun; Korhonen, Frans; Hao, Jiming; Petäjä, Tuukka; Kangasluoma, Juha (2018)
    Classifying sub-3 nm particles effectively with relatively high penetration efficiencies and sizing resolutions is important for atmospheric new particle formation studies. A high-resolution supercritical differential mobility analyzer (half-mini DMA) was recently improved to classify aerosols at a sheath flow rate less than 100 L/min. In this study, we characterized the transfer functions, the penetration efficiencies, and the sizing resolution of the new half-mini DMA at the aerosol flow rate of 2.5-10 L/min and the sheath flow rate of 25-250 L/min using tetra-alkyl ammonium ions and tungsten oxide particles. The transfer functions of the new half-mini DMA at an aerosol flow rate lower than 5 L/min and a sheath flow rate lower than 150 L/min agree well with predictions using a theoretical diffusing transfer function. The penetration efficiencies can be approximated using an empirical formula. When classifying 1.48 nm molecular ions at an aerosol-to-sheath flow ratio of 5/50 L/min, the penetration efficiency, the sizing resolution, and the multiplicative broadening factor of the new half-mini DMA are 0.18, 6.8, and 1.11, respectively. Compared to other sub-3 nm DMAs applied in atmospheric measurements (e.g. the mini-cyDMA, the TSI DMA 3086, the TSI nanoDMA 3085, and the Grimm S-DMA), the new half-mini DMA characterized in this study is able to classify particles at higher aerosol and sheath flow rates, leading to a higher sizing resolution at the same aerosol-to-sheath flow ratio. Accordingly, the new half-mini DMA can reduce the uncertainties in atmospheric new particle formation measurement if coupled with an aerosol detector that could work at the corresponding high aerosol flow rate. (c) 2018 American Association for Aerosol Research
  • Vuori, Miika; Martikainen, Jaana E.; Koski-Pirilä, Anna; Sourander, Andre; Puustjärvi, Anita; Aronen, Eeva T.; Chudal, Roshan; Saastamoinen, Leena K. (2020)
    Using population-based register data, we examine the association between children's birth month and ADHD medication use in a single jurisdiction (Finland). OBJECTIVES: The youngest children in a classroom are at increased risk of being medicated for attention-deficit/hyperactivity disorder (ADHD). We examined the association between children's birth month and ADHD medication rates in Finland. METHODS: Using a population-based study, we analyzed ADHD medication use among children born in 2005 to 2007. Cases (n= 7054) were identified from the first purchase of medication for ADHD. Cox proportional hazard models and hazard ratios (HRs) were examined by birth month and sex. Finnish children start first grade in the year of their seventh birthday. The cutoff date is December 31. RESULTS: Risk of ADHD medication use increased throughout the year by birth month (ie, January through April to May through August to September through December). Among boys born in September to December, the association remained stable across cohorts (HR: 1.3; 95% confidence interval [CI]: 1.1-1.5). Among girls born in September to December, the HR in the 2005 cohort was 1.4 (95% CI: 1.1-1.8), whereas in the 2007 cohort it was 1.7 (95% CI: 1.3-2.2). In a restricted follow-up, which ended at the end of the year of the children's eighth birthday, the HRs for boys and girls born in September to December 2007 were 1.5 (95% CI: 1.3-1.7) and 2.0 (95% CI: 1.5-2.8), respectively. CONCLUSIONS: Relative immaturity increases the likelihood of ADHD medication use in Finland. The association was more pronounced during the first school years. Increased awareness of this association is needed among clinicians and teachers.
  • Turku, M.; Lepistö, O.; Lunden, J. (2018)
    Official food control inspections (official inspections) of food establishments and third party audits of food safety management systems (FSMSs) based on international standards both focus on food safety, which has raised discussions on whether FSMSs and their audits could reduce official inspections in food establishments. The aim of this study was to investigate whether the findings of official inspections and third party audits in food establishments are in alignment and to survey the inspectors' and food business operators' (FBOs) perceptions of official inspections and audits. The results can be used in planning the use of audit results as part of official food control. The results show that both inspectors and auditors recognized non-compliances/non-conformities, but significant discrepancies between the findings of official inspections and audits existed, making the utilization of audit results challenging. However, most of the FBOs and inspectors agreed that official inspections and audits overlap, and the majority also agreed that audits of a certified FSMS could under certain circumstances reduce official inspections. (C) 2017 Elsevier Ltd. All rights reserved.
  • Sullanmaa, Jenni; Pyhältö, Kirsi; Pietarinen, Janne; Soini, Tiina; Soini, Tiina (2019)
    Purpose Shared understandings of curriculum reform within and between the levels of the educational system are suggested to be crucial for the reform to take root. The purpose of this paper is to explore variation in perceived curriculum coherence and school impact among state- and district-level stakeholders. Design/methodology/approach The participants (n=666) included state- and district-level stakeholders involved in a national curriculum reform in Finland. Latent profile analysis was employed to identify profiles based on participants' perceptions of the core curriculum's coherence and the reform's impact on school development. Findings Two profiles were identified: high coherence and impact, and lower consistency of the intended direction and impact. State-level stakeholders had higher odds of belonging to the high coherence and impact profile than their district-level counterparts. Practical implications The results imply that more attention needs to be paid in developing a shared and coherent understanding particularly of the intended direction of the core curriculum as well as the reform's effects on school-level development among state- and district-level stakeholders. Originality/value The study contributes to the literature on curriculum reform by shedding light on the variation in perceived curriculum coherence and school impact of those responsible for a large-scale national curriculum reform process at different levels of the educational system.
  • Scali, Salvatore T.; Beck, Adam; Sedrakyan, Art; Mao, Jialin; Behrendt, Christian-Alexander; Boyle, Jonathan R.; Venermo, Maarit; Faizer, Rumi; Schermerhorn, Marc; Beiles, Barry; Szeberin, Zoltan; Eldrup, Nikolaj; Thomson, Ian; Cassar, Kevin; Altreuther, Martin; Debus, Sebastian; Johal, Amundeep; Bjorck, Martin; Cronenwett, Jack L.; Mani, Kevin (2021)
    Objective: As open abdominal aortic aneurysm (AAA) repair (OAR) rates decline in the endovascular era, the endorsement of minimum volume thresholds for OAR is increasingly controversial, as this may affect credentialing and training. The purpose of this analysis was to identify an optimal centre volume threshold that is associated with the most significant mortality reduction after OAR, and to determine how this reflects contemporary practice. Methods: This was an observational study of OARs performed in 11 countries (2010 - 2016) within the International Consortium of Vascular Registry database (n = 178 302). The primary endpoint was post-operative in hospital mortality. Two different methodologies (area under the receiving operating curve optimisation and Markov chain Monte Carlo procedure) were used to determine the optimal centre volume threshold associated with the most significant mortality improvement. Results: In total, 154 912 (86.9%) intact and 23 390 (13.1%) ruptured AAAs were analysed. The majority (63.1%; n = 112 557) underwent endovascular repair (EVAR) (OAR 36.9%; n = 65 745). A significant inverse relationship between increasing centre volume and lower peri-operative mortality after intact and ruptured OAR was evident (p < .001) but not with EVAR. An annual centre volume of between 13 and 16 procedures per year was associated with the most significant mortality reduction after intact OAR (adjusted predicted mortality < 13 procedures/year 4.6% [95% confidence interval 4.0% - 5.2%] vs. = 13 procedures/year 3.1% [95% CI 2.8% - 3.5%]). With the increasing adoption of EVAR, the mean number of OARs per centre (intact + ruptured) decreased significantly (2010 - 2013 = 35.7; 2014 - 2016 = 29.8; p < .001). Only 23% of centres (n = 240/1 065) met the >= 13 procedures/year volume threshold, with significant variation between nations (Germany 11%; Denmark 100%). Conclusion: An annual centre volume of 13 - 16 OARs per year is the optimal threshold associated with the greatest mortality risk reduction after treatment of intact AAA. However, in the current endovascular era, achieving this threshold requires significant re-organisation of OAR practice delivery in many countries, and would affect provision of non-elective aortic services. Low volume centres continuing to offer OAR should aim to achieve mortality results equivalent to the high volume institution benchmark, using validated data from quality registries to track outcomes.
  • Hjort, Line; Moller, Sofie Lykke; Minja, Daniel; Msemo, Omari; Nielsen, Birgitte Bruun; Christensen, Dirk Lund; Theander, Thor; Nielsen, Karsten; Larsen, Lise Grupe; Grunnet, Louise Groth; Groop, Leif; Prasad, Rashmi; Lusingu, John; Schmiegelow, Christentze; Bygbjerg, Ib C. (2019)
    Purpose Low-income and middle-income countries such as Tanzania experience a high prevalence of noncommunicable diseases (NCDs), including anaemia. Studying if and how anaemia affects growth, placenta development, epigenetic patterns and newborns' risk of NCDs may provide approaches to prevent NCDs. Participants The FOETALforNCD (FOetal Exposure and Epidemiological Transitions: the role of Anaemia in early Life for Non-Communicable Diseases in later life) Study is a population-based preconception, pregnancy and birth cohort study (n= 1415, n= 538, n= 427, respectively), conducted in a rural region of North-East Tanzania. All participants were recruited prior to conception or early in pregnancy and followed throughout pregnancy as well as at birth. Data collection included: maternal blood, screening for NCDs and malaria, ultrasound in each trimester, neonatal anthropometry at birth and at 1 month of age, cord blood, placental and cord biopsies for stereology and epigenetic analyses. Findings to date At preconception, the average age, body mass index and blood pressure of the women were 28 years, 23 kg/m(2) and 117/75 mm Hg, respectively. In total, 458 (36.7%) women had anaemia (haemoglobin Hb <12 g/dL) and 34 (3.6%) women were HIV-positive at preconception. During pregnancy 359 (66.7%) women had anaemia of which 85 (15.8%) women had moderate-tosevere anaemia (Hb = 9 g/dL) and 33 (6.1%) women had severe anaemia (Hb = 8 g/dL). In total, 185 (34.4%) women were diagnosed with malaria during pregnancy. Future plans The project will provide new knowledge on how health, even before conception, might modify the risk of developing NCDs and how to promote better health during pregnancy. The present project ended data collection 1 month after giving birth, but follow-up is continuing through regular monitoring of growth and development and health events according to the National Road Map Strategic Plan in Tanzania. This data will link fetal adverse event to childhood development, and depending on further grant allocation, through a life course follow-up.
  • Santos, Susana; Eekhout, Iris; Voerman, Ellis; Gaillard, Romy; Barros, Henrique; Charles, Marie-Aline; Chatzi, Leda; Chevrier, Cecile; Chrousos, George P.; Corpeleijn, Eva; Costet, Nathalie; Crozier, Sarah; Doyon, Myriam; Eggesbo, Merete; Fantini, Maria Pia; Farchi, Sara; Forastiere, Francesco; Gagliardi, Luigi; Georgiu, Vagelis; Godfrey, Keith M.; Gori, Davide; Grote, Veit; Hanke, Wojciech; Hertz-Picciotto, Irva; Heude, Barbara; Hivert, Marie-France; Hryhorczuk, Daniel; Huang, Rae-Chi; Inskip, Hazel; Jusko, Todd A.; Karvonen, Anne M.; Koletzko, Berthold; Kupers, Leanne K.; Lagstrom, Hanna; Lawlor, Debbie A.; Lehmann, Irina; Lopez-Espinosa, Maria-Jose; Magnus, Per; Majewska, Renata; Mäkelä, Johanna; Manios, Yannis; McDonald, Sheila W.; Mommers, Monique; Morgen, Camilla S.; Moschonis, George; Murinova, Lubica; Newnham, John; Nohr, Ellen A.; Andersen, Anne-Marie Nybo; Oken, Emily; Oostvogels, Adriette J. J. M.; Pac, Agnieszka; Papadopoulou, Eleni; Pekkanen, Juha; Pizzi, Costanza; Polanska, Kinga; Porta, Daniela; Richiardi, Lorenzo; Rifas-Shiman, Sheryl L.; Roeleveld, Nel; Santa-Marina, Loreto; Santos, Ana C.; Smit, Henriette A.; Sorensen, Thorkild I. A.; Standl, Marie; Stanislawski, Maggie; Stoltenberg, Camilla; Thiering, Elisabeth; Thijs, Carel; Torrent, Maties; Tough, Suzanne C.; Trnovec, Tomas; van Gelder, Marleen M. H. J.; van Rossem, Lenie; von Berg, Andrea; Vrijheid, Martine; Vrijkotte, Tanja G. M.; Zvinchuk, Oleksandr; van Buuren, Stef; Jaddoe, Vincent W. V. (2018)
    BackgroundGestational weight gain differs according to pre-pregnancy body mass index and is related to the risks of adverse maternal and child health outcomes. Gestational weight gain charts for women in different pre-pregnancy body mass index groups enable identification of women and offspring at risk for adverse health outcomes. We aimed to construct gestational weight gain reference charts for underweight, normal weight, overweight, and grades 1, 2 and 3 obese women and to compare these charts with those obtained in women with uncomplicated term pregnancies.MethodsWe used individual participant data from 218,216 pregnant women participating in 33 cohorts from Europe, North America, and Oceania. Of these women, 9065 (4.2%), 148,697 (68.1%), 42,678 (19.6%), 13,084 (6.0%), 3597 (1.6%), and 1095 (0.5%) were underweight, normal weight, overweight, and grades 1, 2, and 3 obese women, respectively. A total of 138, 517 women from 26 cohorts had pregnancies with no hypertensive or diabetic disorders and with term deliveries of appropriate for gestational age at birth infants. Gestational weight gain charts for underweight, normal weight, overweight, and grade 1, 2, and 3 obese women were derived by the Box-Cox t method using the generalized additive model for location, scale, and shape.ResultsWe observed that gestational weight gain strongly differed per maternal pre-pregnancy body mass index group. The median (interquartile range) gestational weight gain at 40weeks was 14.2kg (11.4-17.4) for underweight women, 14.5kg (11.5-17.7) for normal weight women, 13.9kg (10.1-17.9) for overweight women, and 11.2kg (7.0-15.7), 8.7kg (4.3-13.4) and 6.3kg (1.9-11.1) for grades 1, 2, and 3 obese women, respectively. The rate of weight gain was lower in the first half than in the second half of pregnancy. No differences in the patterns of weight gain were observed between cohorts or countries. Similar weight gain patterns were observed in mothers without pregnancy complications.ConclusionsGestational weight gain patterns are strongly related to pre-pregnancy body mass index. The derived charts can be used to assess gestational weight gain in etiological research and as a monitoring tool for weight gain during pregnancy in clinical practice.
  • Niestroj, Lisa-Marie; Du, Juanjiangmeng; Nothnagel, Michael; May, Patrick; Palotie, Aarno; Daly, Mark J.; Nürnberg, Peter; Blümcke, Ingmar; Lal, Dennis (2018)
    Objective Increasing availability of surgically resected brain tissue from patients with focal epilepsy and focal cortical dysplasia or low-grade glioneuronal tumors has fostered large-scale genetic examination. However, assessment of pathogenicity of germ line and somatic variants remains difficult. Here, we present a state-of-the-art evaluation of reported genes and variants associated with epileptic brain lesions. Methods Results We critically reevaluated the pathogenicity for all neuropathology-associated variants reported to date in the PubMed and ClinVar databases, including 101 neuropathology-associated missense variants encompassing 11 disease-related genes. We assessed gene variant tolerance and classified all identified missense variants according to guidelines from the American College of Medical Genetics and Genomics (ACMG). We further extended the bioinformatic variant prediction by introducing a novel gene-specific deleteriousness ranking for prediction scores. Application of ACMG guidelines and in silico gene variant tolerance analysis classified only seven of 11 genes to be likely disease-associated according to the reported disease mechanism, whereas 61 (60.4%) of 101 variants of those genes were classified as of uncertain significance, 37 (36.6%) as being likely pathogenic, and 3 (3%) as being pathogenic. Significance We concluded that the majority of neuropathology-associated variants reported to date do not have enough evidence to be classified as pathogenic. Interpretation of lesion-associated variants remains challenging, and application of current ACMG guidelines is recommended for interpretation and prediction.
  • Hemminki, Kari; Srivastava, Aayushi; Rachakonda, Sivaramakrishna; Bandapalli, Obul; Nagore, Eduardo; Hemminki, Akseli; Kumar, Rajiv (2020)
    Background When germline mutations are suspected as causal in cancer, patient DNA may be sequenced to detect variants in relevant genes. If a particular mutation has not been reported in reliable family studies, genetic counselors are facing a dilemma of appropriately informing patients. Many sequencing facilities provide an interpretation of the findings based on the available sequence databases or on prediction tools that are curated from bioinformatics and mechanistic datasets. The counseling dilemma is exacerbated if the pedigree data are not informative but the in silico predictions suggest pathogenicity. Methods We present here a real world example of the c.256G > ACDKN2Avariant, which was detected in one melanoma patient where two siblings were diagnosed with melanoma in situ. We investigated a detailed family history of the affected siblings in order to survey probability of the cancer risks within the context to this mutation. Results This c.256G > ACDKN2Avariant was detected in one of the brothers and in the melanoma-free mother while the other brother in the family tested negative. The variant had been previously described in one patient from a melanoma family. In the family under investigation, the mother's 16 first-and second-degree relatives had survived past the median onset age for melanoma and none presented melanoma. We tested the variant using multiple bioinformatic tools that all predicted deleteriousness of the variant. The genetic counseling report to the melanoma patient stated that theCDKN2Avariant was 'likely pathogenic' and the disease was defined as 'likely hereditary melanoma'. Conclusions The pedigree data showed at the most a low penetrance variant, which, if taken into consideration, might have altered the provided diagnosis. When dealing with 'practically' unknown variants the counselors would be advised to incorporate a detailed family history rather than basing predictions on functionality provided by sequencing facilities.
  • Remes, Satu Maria; Leijon, Helena; Vesterinen, Tiina; Louhimo, Johanna; Pulkkinen, Ville; Ezer, Sini; Kere, Juha; Haglund, Caj; Arola, Johanna (2020)
    Neuroendocrine tumors (NETs) are often diagnosed from the metastases of an unknown primary tumor. Specific immunohistochemical (IHC) markers indicating the location of a primary tumor are needed. The proprotein convertase subtilisin/kexin type 2 (PCSK2) is found in normal neural and neuroendocrine cells, and known to express in NETs. We investigated the tissue microarray (TMA) of 86 primary tumors from 13 different organs and 9 metastatic NETs, including primary tumor-metastasis pairs, for PCSK2 expression with polymer-based IHC. PCSK2 was strongly positive in all small intestine and appendiceal NETs, the so-called midgut NETs, in most pheochromocytomas and paragangliomas, and in some of the typical and atypical pulmonary carcinoid tumors. NETs showing strong positivity were re-evaluated in larger tumor cohorts confirming the primary observation. In the metastases, the expression of PCSK2 mirrored that of the corresponding primary tumors. We found negative or weak staining in NETs from the thymus, gastric mucosa, pancreas, rectum, thyroid, and parathyroid. PCSK2 expression did not correlate with Ki-67 in well-differentiated NETs. Our data suggest that PCSK2 positivity can indicate the location of the primary tumor. Thus, PCSK2 could function in the IHC panel determined from screening metastatic NET biopsies of unknown primary origins.
  • Mesihaa, Samuel; Rasanen, Ilpo; Ojanpera, Ilkka (2018)
    Gas chromatography (GC) hyphenated with nitrogen chemiluminescence detection (NCD) and quadrupole time-of-flight mass spectrometry (QTOFMS) was applied for the first time to the quantitative analysis of new psychoactive substances (NPS) in urine, based on the N-equimolar response of NCD. A method was developed and validated to estimate the concentrations of three metabolites of the common stimulant NPS alpha-pyrrolidinovalerophenone (alpha-PVP) in spiked urine samples, simulating an analysis having no authentic reference standards for the metabolites and using the parent drug instead for quantitative calibration. The metabolites studied were OH-alpha-PVP (M1), 2 ''-oxo-alpha-PVP (M3), and N,N-bis-dealkyl-PVP (2-amino-1-phenylpentan-1-one; M5). Sample preparation involved liquid-liquid extraction with a mixture of ethyl acetate and butyl chloride at a basic pH and subsequent silylation of the sec-hydroxyl and prim-amino groups of M1 and M5, respectively. Simultaneous compound identification was based on the accurate masses of the protonated molecules for each compound by QTOFMS following atmospheric pressure chemical ionization. The accuracy of quantification of the parent-calibrated NCD method was compared with that of the corresponding parent-calibrated QTOFMS method, as well as with a reference QTOFMS method calibrated with the authentic reference standards. The NCD method produced an equally good accuracy to the reference method for alpha-PVP, M3 and M5, while a higher negative bias (25%) was obtained for M1, best explainable by recovery and stability issues. The performance of the parent-calibrated QTOFMS method was inferior to the reference method with an especially high negative bias (60%) for M1. The NCD method enabled better quantitative precision than the QTOFMS methods To evaluate the novel approach in casework, twenty post-mortem urine samples previously found positive for alpha-PVP were analyzed by the parent calibrated NCD method and the reference QTOFMS method. The highest difference in the quantitative results between the two methods was only 33%, and the NCD method's precision as the coefficient of variation was better than 13%. The limit of quantification for the NCD method was approximately 0.25 mg/mL in urine, which generally allowed the analysis of alpha-PVP and the main metabolite M1. However, the sensitivity was not sufficient for the low concentrations of M3 and M5. Consequently, while having potential for instant analysis of NPS and metabolites in moderate concentrations without reference standards, the NCD method should be further developed for improved sensitivity to be more generally applicable. (c) 2018 Elsevier B.V. All rights reserved.
  • Koutsoklenis, Athanasios; Honkasilta, Juho; Brunila, Kristiina (2020)
    Attention Deficit Hyperactivity Disorder (ADHD) is a controversial phenomenon and the link between schooling and the burgeoning occurrence of ADHD diagnoses is problematic. This paper contributes to the discussion regarding the issue by providing a literature review of the evidence on the influence of relative age effect (RAE) on being diagnosed with ADHD. Firstly, the review presents a general cross-national trend for a positive association between relative age and the probability of being diagnosed with ADHD compared to peers, thus showing that the younger-in-class children are more likely to be diagnosed with ADHD. Secondly, this paper outlines and discusses the suggested explanations of the phenomenon as depicted in the reviewed literature. Finally, the paper proceeds to provide alternative frameworks for the explanation of the RAE on ADHD diagnosis that go beyond individual psychopathology and instead take into account the broader social, cultural and political contexts in which the phenomenon takes place.