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We study existence, uniqueness, and optimal regularity of solutions to transmission problems for harmonic functions with $C^{1,\alpha}$ interfaces. For this, we develop a novel geometric stability argument based on the mean value property., Comment: 25 pages, 2 figures

Mango is the second most commercialized tropical fruit in the world, and Mexico is the major exporter. In terms of mango production, Manila´s variety represents a quarter of the total mangoes production in Mexico. However, the changes that occur on the phenolic compounds during the Manila mango ripening process are unknown. Quantitative analysis of the major phenolic compounds was conducted at different maturity stages, using several spectrophotometric measurements and by high-performance liquid chromatography (HPLC). At the late ripening stage was observed the biggest content in pulp and peel of total phenols (577 and 10547 mg EAG /100 g), flavonoids (95.33 and 537 mg EQ/100 g), and antioxidant capacity by DPPH (25 and 347 mmol TE/100 g). Some bioactive compounds achieve their highest values at optimal consumption ripening. Although they diminish when the fruit reaches a senescence appearance. This is the first study to prove that mangiferin by itself shows a higher correlation in antioxidant capacity compared to other phenolic compounds in mango peel, and this suggest that phenolic compounds may have an important role in the postharvest antioxidant metabolism in Manila mango fruit. On the other hand, the results show that the peel compared to the pulp contains higher amounts of total phenols, flavonoids, gallic acid, mangiferin and antioxidant capacity, so its use as an ingredient in the preparation of functional food products is recommended. More studies are needed to go in-depth in the changes of the content of phytochemicals during the ripening process in the peel and pulp mango, which ones could be caused by the hormones responsible for ripening in the fruit, such as ethylene, and bioavailability of these compounds at different stages of maturation. El mango es la segunda fruta tropical más comercializada del mundo y México es el principal exportador. En términos de producción de mango, la variedad Manila representa una cuarta parte de la producción total de mangos en México. Sin embargo, se desconocen los cambios que ocurren en los compuestos fenólicos durante el proceso de maduración del mango Manila. El análisis cuantitativo de los principales compuestos fenólicos se realizó en diferentes etapas de madurez, utilizando varias medidas espectrofotométricas y mediante cromatografía líquida de alta resolución (HPLC). En la etapa de madurez tardía se observó el mayor contenido en pulpa y cáscara de fenoles totales (577 y 10547 mg EAG / 100 g), flavonoides (95.33 y 537 mg EQ / 100 g) y capacidad antioxidante por DPPH (25 y 347 mmol TE / 100 g). Algunos compuestos bioactivos alcanzan sus valores más altos en el punto de madurez óptima. Aunque disminuyen cuando el fruto adquiere una apariencia de senescencia. Este es el primer estudio que demuestra que la mangiferina por sí misma presenta una alta correlación con la capacidad antioxidante en comparación con otros compuestos fenólicos de la cáscara de mango, y esto sugiere que los compuestos fenólicos pueden tener un papel importante en el metabolismo antioxidante postcosecha en el mango Manila. Por otro lado, los resultados muestran que la cáscara comparada con la pulpa contiene mayores cantidades de fenoles totales, flavonoides, ácido gálico, mangiferin y capacidad antioxidante por DPPH, por lo que se recomienda su uso como ingrediente en la elaboración de productos alimenticios fucionales. Se necesitan más estudios para profundizar en los cambios del contenido de fitoquímicos durante el proceso de maduración en la cáscara y pulpa del mango, los cuáles podrían ser provocados por las hormonas responsables de la maduración en el fruto, como el etileno, y la biodisponibilidad de estos compuestos en diferentes etapas de maduración.

Breast cancer diagnosis is one of the most difficult events that a woman can experience during her life and it usually produces high levels of stress. Global measures of perceived stress are useful for screening and for comparing stress levels between cancer patients and other clinical and nonclinical populations. One such instrument that is widely used is the Perceived Stress Scale (pss-10), but its psychometric properties have scarcely been analysed with breast cancer patients. The aim of this study was to provide validity evidence regarding the use of the 10-item version of the pss-10 as a tool for measuring perceived stress in this context. Participants were 215 Spanish breast cancer patients who completed the PSS-10 and the DASS-21, a measure of affective distress (depression, anxiety, and stress). The internal structure of the PSS-10 was examined through confirmatory factor analysis (CFA), and the reliability of test scores was estimated using McDonald's omega coefficient. Validity evidence based on relationships with other variables was also obtained using correlation analysis. The CFA supported a correlated two-factor structure: perceived helplessness (six negatively worded items) and perceived self-efficacy (four positively worded items). Reliability coefficients for scores on these two factors were 0.87 and 0.73, respectively. Scores on affective distress (DASS-21) were strongly and positively correlated with perceived helplessness and moderately and negatively correlated with perceived self-efficacy. The PSS-10 is an adequate tool for measuring perceived stress in the breast cancer context and it may be useful for identifying women at risk of psychological maladjustment.

Background Patients with chronic diseases have increased needs for assistance and care. The objective of this study was to describe the characteristics and use of primary care (PC) and hospital care (HC) health services by chronic patients according to risk level based on adjusted morbidity groups (AMG) and to analyze the associated factors. Methods Cross-sectional descriptive observational study. Patients from a basic health area classified as chronically ill by the AMG classification system of the Madrid PC electronic medical record were included. Sociodemographic, clinical-care characteristics (classified as predisposing factors or need factors) and service utilization variables were collected. Univariate, bivariate and simple linear regression analyses were performed. Results The sample consisted of 9866 chronic patients and 8332 (84.4%) used health services. Of these service users, 63% were women, mean age was 55.7 (SD = 20.8), 439 (5.3%) were high risk, 1746 (21.2%) were medium risk, and 6041(73.4%) were low risk. A total of 8226 (98.7%) were PC users, and 4284 (51.4%) were HC users. The average number of annual contacts with PC was 13.9 (SD = 15); the average number of contacts with HC was 4.8 (SD = 6.2). Predisposing factors associated with services utilization at both care levels were: age (B coefficient [BC] = 0.03 and 0.018, 95% CI = 0.017–0.052 and 0.008–0.028, respectively, for PC and HC) and Spanish origin (BC = 0.962 and 3.396, 95% CI = 0.198–1.726 and 2.722–4.070); need factors included: palliative care (BC = 10,492 and 5047; 95% CI = 6457–14,526 and 3098-6995), high risk (BC = 4631 and 2730, 95% CI = 3022–6241 and 1.949–3.512), number of chronic diseases (BC = 1.291 and 0.222, 95% CI = 1.068–1.51 and 0.103–0.341) and neoplasms (BC = 2.989 and 4.309, 95% CI = 1.659–4.319 and 3.629–4.989). Conclusions The characteristics and PC and HC service utilization of chronic patients were different and varied according to their AMG risk level. There was greater use of PC services than HC services, although utilization of both levels of care was high. Service use was related to predisposing factors such as age and country of origin and, above all, to need factors such as immobility, high risk, and number and type of chronic diseases that require follow-up and palliative care.

Aims This study reports the foundations, strategies, and results of an institutional change experience based on the combination of participatory-action-research and new currents of collective mobilization and political participation. It aimed to achieve the institution's greater social commitment and a more participatory and transparent management. Methods The process took place in a Spanish public university and was promoted and coordinated by a Work Group that emerged from grassroots university community. Collective diagnosis was performed through face-to-face strategies (global, sectorial, and faculty meetings) and virtual tools (web-blog, on-line surveys, shared documents). Collective action combined nonformal with formal institutional participation and applied hybrid activism, self-organization in horizontal structures and integrative conflict management. Results A sequential process of diagnosis, collective action, and negotiation was implemented. As a result, the university Governing Team, representatives from different sectors and members of the Work Group worked jointly to define several institutional actions that were thereafter launched. Those actions aimed to improve institutional participation and transparency, and greater institutional social commitment. Conclusion The combination of participatory-action-research and new ways of collective action can be an excellent tool to draw institutions towards greater social engagement, thus contributing to sustainable social change. A model to guide institutional change is drafted.

Introduction and objectives: The relationship between allergic diseases and behavioural disorders is still unclear. The objective of this study was to describe and compare children's behaviour (internalising and externalising) across a sample of children aged 6-11 years with and without allergic diseases. Materials and methods: This was a cross-sectional observational case-control study. A survey to 366 families (194 allergic cases and 172 controls), including a child behaviour checklist (CBCL) and a socio-demographic questionnaire with questions related to family, school education, health conditions and allergy symptoms, was administered. Results: Children with a diagnosis of allergy showed higher scores in the overall CBCL score (standardised mean differences [SMD] = 0.47; confidence intervals [CI]: 0.26-0.68) and in the internalising and externalising factors (SMD = 0.52 and SMD = 0.36, respectively) than non-allergic children. Odds ratio (OR) analyses showed a higher risk (OR = 2.76; 95% CI [1.61 to 4.72]) of developing a behavioural difficulty in children diagnosed with allergies. Age and level of asthma appear as modulatory variables. Conclusions: Children aged 6-11 years diagnosed with allergies showed larger behavioural problems than non-allergic children, especially in the case of internalising behaviours. These findings suggest the importance of attending to them and treating them in the early stages of diagnosis to avoid future psychological disorders. (C) 2021 Codon Publications. Published by Codon Publications.

Background Most family members of potential organ donors experience the death of their relative in an intensive care unit. While under an emotional burden, bereaved relatives must make a decision that will affect the life of other patients. A better understanding of grief within the context of organ donation will help intensive care unit staff better support families during this process. Objectives To empirically describe the emotional reactions of potential organ donors’ family members facing a loved one’s death and analyze the relationship of these reactions to factors that occur in the process of illness and death. Methods A prospective observational study was conducted in 16 Spanish hospitals for 36 months. Data of 421 relatives of potential organ donors, collected through a previously validated instrument, included relatives’ emotional responses, deceased’s and relatives’ characteristics, circumstances of death, and behavior of health care staff. Results Unexpected deaths were linked to more intense emotional reactions and less acceptance of death than were anticipated deaths. Additional stressors, such as perception of poor treatment by hospital staff, perception of deficient medical care, and poor relationships among family members, were associated with stronger reactions. Conclusions Observation and analysis of the factors studied may help hospital staff members anticipate bereaved relatives’ emotional reactions and provide better support during the grieving process, increasing family members’ well-being and facilitating a better-informed organ donation decision.

The relationship between allergic diseases and behavioural disorders is still unclear. The objective of this study was to describe and compare children's behaviour (internalising and externalising) across a sample of children aged 6-11 years with and without allergic diseases.This was a cross-sectional observational case-control study. A survey to 366 families (194 allergic cases and 172 controls), including a child behaviour checklist (CBCL) and a socio-demographic questionnaire with questions related to family, school education, health conditions and allergy symptoms, was administered.Children with a diagnosis of allergy showed higher scores in the overall CBCL score (standardised mean differences [SMD] = 0.47; confidence intervals [CI]: 0.26-0.68) and in the internalising and externalising factors (SMD = 0.52 and SMD = 0.36, respectively) than non-allergic children. Odds ratio (OR) analyses showed a higher risk (OR = 2.76; 95% CI [1.61 to 4.72]) of developing a behavioural difficulty in children diagnosed with allergies. Age and level of asthma appear as modulatory variables.Children aged 6-11 years diagnosed with allergies showed larger behavioural problems than non-allergic children, especially in the case of internalising behaviours. These findings suggest the importance of attending to them and treating them in the early stages of diagnosis to avoid future psychological disorders.

Rationale Family refusal to organ donation of a deceased relative represents one of the most important barriers to organ transplantation. Although a large literature about family decisions has amassed, the existing evidence needs further integration and structuring. Objective This study seeks to analyse relationships between bereaved relatives’ decisions and a wide range of factors that converge in the family decision process, including interactions and complex relationship patterns, and taking psychosocial theoretical frameworks as reference to conceptualize empirical findings. Method This observational study examined 16 Spanish hospitals during a 36-month period. Transplant coordination teams collected data of 421 cases of family decision processes about donation (338 donations/83 refusals) through a previously validated instrument. Indicators of the following factors were collected: deceased's characteristics; circumstances of death; bereaved relatives' characteristics, beliefs, and expressions; behaviour of health and coordination staff; and family's emotional responses. Three global hypotheses related to bivariate and multivariate relations of factors with family decisions and relationships/interactions among factors were tested. Results Relatives' beliefs about the deceased's wishes concerning donation are the strongest predictor of family decisions. However, family decisions are also related to the deceased's characteristics, relatives' characteristics, satisfaction with medical attention, satisfaction with personal treatment and relatives' emotional responses, and other factors. Relatives' emotional reactions are related to satisfaction with health-staff interventions and condition family decision, even if deceased's will concerning donation is known and positive. Relatives' beliefs about deceased's wishes concerning donation vary as a function of deceased's characteristics and according to relatives' characteristics. Conclusions Understanding of family decisions underlying organ donation may greatly benefit from a more complex, integrated, and theoretically based approach. Educational efforts should stress the need to register or simply communicate own willingness to donate organs. However, an adequate training and performance of the health-staff involved in the organ donation process may generate substantive differences in consent rates.

The loss of traditional knowledge, concomitant with changes in livelihoods, languages, and demographics of indigenous and local groups, is a global concern. However, documenting such loss poses serious methodological challenges. Comparing the results of contemporary studies with past research is often problematic due to methodological differences. Here, comparing studies that attempted to document the traditional ethnobotanical knowledge of the Chacobo of Bolivia, we tried to examine whether knowledge loss was really occurring across more than 100 years or was only researcher’s perception. The Chacobo are a Panoan-speaking tribe of about 1000 members, first visited by researchers in 1911, and subsequently in the 1950s, 1960s, 1970s, 1980s, and 1990s. Each study had different foci, but all recorded ethnobotanical data. The first more detailed anthropological report exists from the late 1960s, and ecological-ethnobotanical studies were conducted in the 1980s and 1990s. Based on available literature, in particular the botanical studies of Boom (1987) and Bergeron (1998), it seemed that Chacobo plant use now centers on income generation. Both Boom (1987) and Bergeron (1998) perceived that traditional plant use related to household artifacts and medicine, as well as traditional crop varieties had almost disappeared. Here, we hypothesized that plant knowledge documented and the perception of so-called knowledge loss observed in these depended completely on the background of the interviewers and the methods employed, and that in a sufficiently comprehensive ethnobotanical study, we would be able to document all species and uses mentioned in previous studies. We tested this hypothesis by conducting a complete ethnobotanical inventory of almost the entire adult Chacobo population, with interviews and plant collection conducted directly by Chacobo counterparts. The results verify our initial hypothesis and showed that the loss of knowledge perceived in previous studies simply was an artifact of the research methods employed. Traditional crop varieties are still widely grown, most Chacobo know, and can name, traditional artifacts, and many still know the names and uses of medicinal species. However, some knowledge, including the manufacture of artifacts and proficient identification of many medicinal plants, is limited to the older generation.

En las dos últimas décadas el aprendizaje autorregulado se ha convertido en uno de los principales focos de la investigación psicoeducativa y en uno de los ejes primordiales de la práctica docente. En este contexto el objetivo de la presente investigación es examinar la existencia de diferencias de género en la motivación académica y en el uso de estrategias de aprendizaje, y comprobar qué ocurre cuando se controla el rendimiento académico previo. La muestra estuvo compuesta por 374 alumnos de 2º curso de Educación Secundaria Obligatoria (ESO). Se emplearon las escalas motivacionales del Patterns of Adaptive Learning Scales (PALS) centradas en el alumno (metas personales y contextuales, creencias de autoeficacia y estrategias self-handicapping) y las escalas cognitivas del MSLQ en su versión española (CEAM II). Los resultados evidencian, en un primer momento, diferencias significativas entre chicos y chicas en todas las escalas motivacionales y de estrategias consideradas, excepto en metas aprendizaje y elaboración. Sin embargo, al controlar el efecto del rendimiento previo, se pudo constatar cómo algunas de estas diferencias desaparecían. A este respecto, se destaca la necesidad de que futuras investigaciones en este campo controlen el rendimiento académico previo, además de analizar con detenimiento los estereotipos que cada género desarrolla y el estilo o sesgo en la respuesta a los cuestionarios de autoinforme según el sexo.

Actualmente es innegable la participación del sistema endocannabinoides (SEC) en la regulación metabólica; ya que su sobre estimulación ha sido relacionada con varias patologías entre las que se encuentran obesidad, diabetes mellitus, retinopatía e hígado graso no alcohólico, entre otras. Estas patologías se relacionan mutuamente a través de alteraciones del metabolismo de los lípidos, como lo es una sobreestimulación de la síntesis de ácidos grasos, una disminución en la beta-oxidación, hiperglicemia causada por un aumento de la gluconeogénesis, así como en la glucólisis, procesos en los cuales se ha descrito al SEC como un participante crucial. Por otro lado, algunos compuestos fitoquímicos, tales como la mangiferina (MGF), han probado sus efectos farmacológicos en el metabolismo de lípidos a nivel hepático y en el control glicémico. Hasta el momento se desconoce el efecto de la mangiferina sobre los receptores de endocannabinoides, por lo que esta revisión trata de mostrar como el sistema de endocannabinoides regula a nivel sistémico (órganos y tejidos) y a nivel central (Sistema Nervioso) la lipogénesis, además de resaltar como la mangiferina participa de manera opuesta al SEC. Finalmente se infiere, con base en la información publicada hasta el momento, una relación clara entre el posible efecto que pueden tener la MGF sobre el SEC.

The emergence of musculoskeletal symptoms (MSSs) in computer workers is a relevant occupational health problem. This study tests a multilevel model of analysis of risk factors in the appearance of musculoskeletal pain and discomfort in computer workers that integrates indicators from different areas: temporal usage patterns, ergonomic factors, psychosocial factors, and individual variables, specifically testing the possible mediating role of the mental workload. A cross-sectional study was performed through online registration with a non-probabilistic sample of 1198 workers from Spanish organizations. The results show that mental workload has a higher association than the rest of the factors with the onset of pain and discomfort in various body areas: neck in men, neck, shoulders and upper back in women. They also support the mediation role of mental workload in the relationship between usage patterns and the appearance of musculoskeletal symptoms. The use of multilevel theoretical models that adequately consider the complexity of the relationships between the different risk factors is necessary for a better understanding and intervention on MSSs in computer workers.

Scope: To examine the association between milk and dairy products intake and the prevalence of cognitive decline among Spanish individuals at high cardiovascular risk. Methods and results: Cross-sectional analyses are performed on baseline data from 6744 adults (aged 55-75 years old). Intake of milk and dairy products is estimated using a food frequency questionnaire grouped into quartiles. The risk of developing cognitive impairment is based on the Mini-Mental State Examination (MMSE). A higher prevalence of cognitive decline was found in subjects who consumed more grams. Patients with worse MMSE score (10-24) consumed a mean of 395.14 ± 12.21 g, while patients with better MMSE score (27-30) consumed a mean of 341.23 ± 2.73 g (p < 0.05). Those subjects with the lower milk consumption (

Although freelisting and semi-structured interviews are widespread methods in ethnobotany, few studies quantitatively examine how these methods may bias results. Using a comprehensive ethnobotanical inventory of palm species, uses and names in the Chacobo tribe of Bolivia, we show that interviews elicit more items than freelists, but the effect is sensitive to sample size, item type and data categorization. This implies that even subtle methodological choices may greatly affect reported results.

The objective of this research was to examine the effects of the instruction method “thinking actively in an academic context (TAAC)” on thinking skills, creativity, self‐regulation and academic achievement. The design was pre‐test–intervention–post‐test with control group. The sample included 46 participants (aged 16 to 18 years), 24 experimental and 22 controls. Before and after application of the method, six instruments were used to measure thinking skills and academic achievement. The method, divided into eight stages, was followed in each didactic unit during an academic course. The method allows teaching the thinking skills, the creativity and the self‐regulation simultaneously with the syllabus content. The results showed that greater changes were obtained with the new method of instruction in all the dependent variables. Relevant scientific and educational implications are drawn from the study.

The purpose of this study was to assess the effects of the instruction method ‘Thinking Actively in an Academic Context’ (TAAC) in the thinking skills of 6th grade students in primary education. The sample consisted of 58 subjects, aged between 11- and 13-years-of-age, 27 in the experimental group and 31 in the control group. A pre-test intervention—post-test design was employed, and the assessment instruments were administered before and after the intervention to measure variables related to thinking and academic achievement. The eight-phase instruction method was administered to all the didactic units of the syllabus-content of environmental knowledge, language and mathematics during one academic course. The stages of the method allow the conjoint teaching of thinking skills and the syllabus-content. The results of the analysis of variance suggest that the intervention produced a significant improvement in both thinking skills and academic achievement, and indicated also that the method produced different effects in reasoning as a function of gender.

The ‘Decision-Making Questionnaire’ (DMQ) was developed and validated in order to examine the factors that affect decision making. The investigation was carried out with two samples, one of 170 participants and the other of 425 of both sexes. Each sample was divided into three age ranges: young students (18–25 years), adults (26–60 years), and seniors (61–75 years). Psychometric analyses revealed satisfactory internal consistency and a first-order factor structure comprising 10 scales: Uncertainty, Time/money pressure, Information and goals, Consequences of the decision, Motivation, Self-regulation, Cognition, Emotion, Social pressure, and Work pressure. These scales in turn yielded a second-order factor structure of Task, Subject, and Context. The results highlight the ways in which youths, adults, and seniors are influenced by diverse factors when making decisions. They also suggest that men are more likely than women to seek and analyse information, whereas women place higher value on the avai...

En las últimas décadas el estudio de las interrelaciones entre cognición y motivación (recogido bajo el constructo de aprendizaje autorregulado o Self-Regulated Learning) se ha convertido en tema central de la Psicología de la Educación y en una de las principales direcciones por donde avanza la disciplina. Dentro de este marco de referencia, el objetivo de la presente investigación es analizar las interrelaciones entre la motivación (metas académicas, creencias de autoeficacia y estrategias self-handicapping), las estrategias de aprendizaje y el rendimiento académico en alumnos de Educación Secundaria. La muestra estuvo compuesta por N= 374 alumnos de 2º curso de la ESO (edad media 13-14 años). Los resultados ponen de relieve que estos alumnos manifiestan una alta motivación intrínseca y una elevada autoconfianza en sus capacidades académicas, además de emplear un gran número de estrategias de aprendizaje, lo cual correlaciona positivamente con el rendimiento académico. Sin embargo, las bajas puntuaciones en algunas de las escalas de estrategias cognitivas, plantea la duda de hasta qué punto se promueve el aprendizaje significativo y autorregulado en este nivel educativo. Finalmente, se proponen una serie de recomendaciones y principios para la promoción del aprendizaje autorregulado en el aula.

El aprendizaje autorregulado (self-regulated learning) ha recibido una atención creciente en las últimas décadas en la investigación psicopedagógica, en cuanto que su promoción en los estudiantes posibilita no sólo mejores resultados académicos, sino también una mayor autonomía y motivación, un claro protagonismo en su proceso de aprendizaje y una necesaria capacidad de transferencia a diferentes situaciones. En este contexto, el objetivo del presente artículo consiste en establecer teóricamente el estado actual de la cuestión en este campo, además de discutir acerca de las principales estrategias didácticas empleadas en la instrucción docente (enseñanza directa de estrategias, modelado, práctica guiada y autónoma, autoobservación, apoyo social y práctica autorreflexiva), atendiendo a su evolución hasta el momento actual. Finalmente, se señalan las líneas que deben contribuir actualmente al desarrollo de la investigación en este campo.

BackgroundRespiratory complications are an important cause of postoperative morbidity. We aimed to investigate whether continuous positive airway pressure (CPAP) administered immediately after major abdominal surgery could prevent postoperative morbidity.MethodsPRISM was an open-label, randomised, phase 3 trial done at 70 hospitals across six countries. Patients aged 50 years or older who were undergoing elective major open abdominal surgery were randomly assigned (1:1) to receive CPAP within 4 h of the end of surgery or usual postoperative care. Patients were randomly assigned using a computer-generated minimisation algorithm with inbuilt concealment. The primary outcome was a composite of pneumonia, endotracheal re-intubation, or death within 30 days after randomisation, assessed in the intention-to-treat population. Safety was assessed in all patients who received CPAP. The trial is registered with the ISRCTN registry, ISRCTN56012545.FindingsBetween Feb 8, 2016, and Nov 11, 2019, 4806 patients were randomly assigned (2405 to the CPAP group and 2401 to the usual care group), of whom 4793 were included in the primary analysis (2396 in the CPAP group and 2397 in the usual care group). 195 (8·1%) of 2396 patients in the CPAP group and 197 (8·2%) of 2397 patients in the usual care group met the composite primary outcome (adjusted odds ratio 1·01 [95% CI 0·81-1·24]; p=0·95). 200 (8·9%) of 2241 patients in the CPAP group had adverse events. The most common adverse events were claustrophobia (78 [3·5%] of 2241 patients), oronasal dryness (43 [1·9%]), excessive air leak (36 [1·6%]), vomiting (26 [1·2%]), and pain (24 [1·1%]). There were two serious adverse events: one patient had significant hearing loss and one patient had obstruction of their venous catheter caused by a CPAP hood, which resulted in transient haemodynamic instability.InterpretationIn this large clinical effectiveness trial, CPAP did not reduce the incidence of pneumonia, endotracheal re-intubation, or death after major abdominal surgery. Although CPAP has an important role in the treatment of respiratory failure after surgery, routine use of prophylactic post-operative CPAP is not recommended.FundingNational Institute for Health Research, Barts Charity, Intersurgical, Association of Anaesthetists, and Sapienza Università di Roma.