Theories of motor control and skill acquisition strongly influence and guide various fields of clinical practice. In last decades, changes in theoretical frameworks related to the conceptualization of brain plasticity, functional structures within the child, and environment have led to a revision of therapy approaches progressing from therapist-driven to child-initiated approaches. Even though theoretical frameworks and clinical practice are closely linked to the child’s body, the profession has paid less attention to theories concerning the body’s role and status in interpersonal relationships when fostering motor control and skill acquisition in children. In this theoretical paper we discuss the theoretical frameworks of motor control and skill acquisition that currently guide clinical practice. Through highlighting valuable contributions of these theories, we explore theoretical and practical benefits pediatric physical therapy can acquire by taking an enactive approach as a means to bring the child as a subject into focus. We rely on enactive concepts of embodiment, autonomy, and participatory sense-making in our exploration to provide an extended understanding of motor control and skill acquisition shaping our beliefs about what counts in therapeutic encounters in pediatric physical therapy. The availability of numerous theoretical frameworks has had implications for how we approach and plan interventions for various pediatric conditions . Over thCurrently the three primary theoretical frameworks discussed in physical therapy related literature are dynamic systems-, perception-action-, and neuronal group selection. These three theories incorporate the most up to date research about motor control and development, aggregated under the umbrella of dynamic systems approaches . DynamicTo enact is how human beings bring forth a world of significances through (inter)actions rather than being receivers of inputs from the environment . By takiIn the first section of this theoretical paper, we provide a brief overview of the dynamic systems approaches and where these theories fall short in addressing the self in development of motor control and skill acquisition. In the second section of the paper, we present the enactive approach by discussing concepts of embodiment, autonomy, and participatory sense-making to expand our understanding of the importance of considering the role of self in development of motor control. In the last section, we discuss the application of an enactive approach to the practice of pediatric physical therapy using hypothetical examples to illustrate the significance of recognizing and acknowledging the child as an embodied subject. We acknowledge that there are several genders but to make the text easy to read we will refer to the child as a she/her/herself throughout the article.1.1.The construct of motor control and skill acquisition is a crosspollination of a broad range of disciplines including anatomy, physiology, psychology, and physical therapy . Motor cDynamic systems theory emphasizes process rather than the product with no one system  considered superior to another in fostering motor development . In shorIn the neuronal group selection theory, the brain is considered important for development . This thThe third dynamic system approach, perception-action, describes perception and action are mutually and reciprocally related, i.e., what the child sees and perceives, shapes how she organizes movement to approach or acquire a specific object or person . This inCommon and inherent in these three theories, is an understanding that development is driven by a connection between different systems, i.e., the maturation of the psychological and physiological systems within the body and the demands placed on children by the environment and task-related experiences . Each ofTouch involves specific therapeutic hands-on techniques to enable and foster movements. For example, touch to increase sensory stimulation, for tissue mobilization, and to address and support sensorimotor systems, particularly in the child with neuromotor and developmental delays . As an a1.2.The theoretical basis of motor control and skill acquisition in dynamic system approaches rests mainly on ontological (what exists) and epistemological (ways of knowing) assumptions inherited from a Cartesian dualism . The CarBy simplifying the role of the individual (child) to an integrated individual-environment system see , which a1.3.Through the lens of the enactive approach and its phenomenological branch, embodiment implies that the child always is in the world as a mind–body, dynamically interacting with the environment. The locus of cognition is expanded from residing in the brain to a ‘mind–body-environment’ synthesis . Thus, eliving and a lived body implies acceptance of an extensive and alternative understanding of motor control and skill acquisition that recognizes mind/consciousness as constituted by embodied movements and actions  and her environment . This imIn sum, an important part of human life is characterized by being a body that is material, dynamic, and self-organizing, while being simultaneously animated and affected by itself and the world . As such2.Sensorimotor life then, is defined as the life the child lives while she is engaged in performing movements, exploring the environment, and interacting with others . The chi2.1.In the formation of bodily becoming, the body as an autonomous system (organism) self-organizes and self-produces itself by regulating its metabolic exchanges and sensorimotor interactions with the social and physical environment . Thus, aThe interaction process, conceptualized as participatory sense-making, plays a central role for the generation of meaning and understanding . Thus, tFrom the beginning of life, the autonomous child communicates through her lived body via postures, movements, and touch, fostering important relationships for participatory sense-making . For theSensorimotor capacities for perception and behavior are already shaped at the time of birth as a result of the infant’s prenatal movements . Thus, tThe child as an embodied subject in its full sense is not just a matter of sensorimotor schema and body image but includes bodily affective states such as emotional factors, motivational dimensions, fatigue, pain, etc. Also, the perceptual sense of the possibility of executing movements and actions will affect the child’s engagement and participatory sense-making. Thus, interest, motivation, and affect are important bodily and emotional states that drive the child’s ability to understand and participate in interactions of concern. For example, a child with bilateral spastic CP may perceive a toy too far away and difficult to reach informing (pre-reflectively) her affective judgment not to reach for it. Hence, simply emphasizing the facilitation of the environment with toys to foster motor control in children may therefore not be sufficient.The bodily states of emotions engender powerful agency and therefore support the child’s subjective desire to explore. The environment may afford many possibilities for exploration and action, but the child does not approach her environment merely based on inherent desire alone but also on what is achievable. Additionally, each possibility in the environment, whether an object or individual, will have its own value to the child. This will be based on what matters to the child as well as her interest in and/or the ability to interact with the object or person. By attributing properties of the world  as being novel, difficult, complex, and/or unexplored, these properties are more likely to be of interest creating transformative changes in the embodied child as the coupling to her environment changes. Interest is therefore related to increased focus, modulated participatory sense-making, motivated engagement, and self-initiated actions. As children progress and transform their experiences, perceptions, and actions will shift and accordingly their goals and intentions start to operate in different ways. Further, individual affect  will differ from one person to another, between situations, relationships, contexts, and time of the day. Possibilities are therefore not equally affordable and will therefore affect body states that foster engagement and participatory sense-making .In therapy then, according to the enactive approach the PT and the child are considered two interacting autonomous embodied agents enacting each other through various forms of participatory sense-making processes. The PT is part of the interaction in which individual sense-making will be affected by the activity of the other(s) to varying degrees . Sometim2.2.feel her movements and proprioceptively learns to perceive the body postures which will optimize her movements. Thus, bodily movements involving proprioception and kinesthesia shape the child’s knowing and the process of knowing resides in her body and in her movements while she is interacting with her surroundings  compared to the enactive approach (the lived body). In the enactive context, movements are phenomenologically anchored in the lived body through pre-reflective self-perception and kinesthesia . Each mooundings . Furtheroundings .According to the enactive perspective, the ‘I’ in this context refers to the child as an embodied agent rather than simply mental consciousness . The chiSpontaneous movements, in general and how they are related to agency, play an essential part in initial learning throughout childhood. The ‘I move’ is therefore an important precondition for all learning, the foundation of ‘I can’ , 2019. Tshe is like as she moves, e.g., reaches for the toy  in a certain way  to enable a sitting child, who is delayed in her motor development, to achieve the task of reaching and gripping a toy placed on the right side slightly in front of her body. The long-sitting child (with her legs in line with her body) initiates a reaching movement with her right arm in a jerky, slow and stereotypical manner but fails due to reduced trunk control and inability to laterally weight shift in sitting. Consequently, the child’s trunk on the right side laterally flexes to the side in an effort to improve stability during reaching, causing her to fall to the right. The PT responds by replacing the child in the long-sitting position and places the toy on a small box closer to the child (still on her right side). Once more, the child initiates reaching movements in the same jerky, slow and stereotypical movement pattern previously used, but this time she succeeds in grasping the toy as the reaching distance, the height, and the location of the toy have been modified. The PT and child practice and repeat this activity over and over while the child continuous to move her arm in a stereotypical movement pattern with her trunk laterally flexed. This situation illustrates a PT who is not directly addressing the child’s lived body to regulate her interaction with the environment (toy) but facilitates the likelihood of success of grasping by re-arranging the specificity of the task; the child’s and the PT’s sense-making remain poorly synchronized individual activities see .Now, consider a situation where the starting point is the same as the situation above, but this is a scenario of high influential mutuality. The PT sits on the floor behind the long-sitting child. The PT places her hands lightly around the child’s trunk to provide sensory inputs to facilitate and guide trunk alignment improving postural stability and bodily awareness. The child can reach with greater fluidity and achieve the toy without falling sideways. In this context, facilitation and guidance should not be interpreted as a static support but rather an intervention to recruit motor activity and provide the child with a perceptual awareness of the optimal positioning to achieve the toy without falling. In this way, the child learns to reach while activating the postural mechanisms required to sustain her sitting posture. Based on the child’s bodily responses and what the PT comprehends through vision and touch and anticipates and perceives, the PT continuously adapts the position and compression of her hands as well as the position of the toy supporting and guiding until the child ‘takes over’. Over time, the PT reduces the control and pressure or even removes her hands, and the child is encouraged to experiment with her newly acquired kinesthetic experiences and developing trunk control as she reaches for the toy in different locations. This type of interaction further expands into a bodily interplay between the PT and the child where the PT alternates between being hands-on and hands-off while the child repeatedly reaches more smoothly and with greater speed and accuracy for the toy. This situation illustrates a child and a PT intervening in each other’s enactments through specific co-regulation of perceptual bodily movements; they are directly participating in the joint process of sense-making where the whole sense-making activity becomes a shared one  see Fig.The above two situations reflect how sense-making arises differently from two seemingly similar but contrasting intersubjective contexts, i.e., different child-environment relations generated different sense-making processes. In both cases the children embraced a perspective on the world by grasping the toy placed in front of them. However, the modulatory engagements in the interactions, i.e., the children’s moderation and incorporation of the sensorimotor flow from the environment into their movements, was different. Although both children achieved the end-goal of grasping the toy, the intent and structure of the therapy delivery placed different demands on their systems, giving rise to different circular coupling to the world and to sense-making.In the first case, the PT only facilitated the task and the environment. Therefore, the role of the PT was to arrange the task and environment in relation to the child’s functional ability. The child struggled with her own body to complete the task. The adaptability and state of her living body were challenged resulting in precarious balance and slow labored movement. The child did not have the ability to vary her own movements and thus regulate her circular coupling to the environment. She was more dependent on the environment and task being regulated to her body to achieve the task. The child remained in her already established movement patterns with no improvement in her reaching movements. In that respect, the task-oriented approach fostered only the child’s kinesthetic feeling of ‘I move’ and ‘I do’ because the child was unable to adapt her own body to the task but rather depended on the task being adjusted to her body and her limited movement abilities. In other words, the child as an autonomous system was not addressed rendering her incapable to adaptively regulate her coupling with her environment.In contrast, in the second example, the child was supported by the PT’s guided facilitation. Although the child was also vulnerable, she managed to modulate her coupling to the environment in a more adaptive manner. We suggest the PT’s facilitation provided sensory input to the child’s emerging body schemas enabling her to regulate her body and actively move her arm and trunk within previously unreachable ranges. The interplay between the child, the PT, and the task, constituted a performing system that enabled the child to explore the possibilities of her own body and to develop new kinesthetic experiences and her own agency. The mutuality in the situation was high and regulatory and contributed to the organization of the child as an autonomous adaptive system. Thus, the child’s embodied intentionality changed allowing her to interact more directly with her surroundings. This fostered promising, immerging, or nascent changes in the child’s ability to reach and grasp., which over time can develop in self-sustaining patterns or habits that will constitute an emerging network of body schemas that can be applied to similar activities . AdditioTo reinforce the significance of the use of (pre-)reflective, guided facilitation, there are several studies which substantiate the importance of various forms of sensory trunk support in children developing typically and atypically . For exaFor the processes of embodied interactions during clinical encounters, the PT’s embodied knowledge becomes central to support and guide the application of her clinical skills with the goal of co-creating optimal changes in the child’s motor function and participation. Additionally, during clinical encounters, the PT’s embodied knowledge should also be directed toward the incorporation of activity and skills to support the child’s state, organization, and agency. Consequently, in embodied interactions with the child the PTs knowledge will rise above a purely cognitive activity to an embodied ‘dance’ with the child and her bodily expressions and intentional movements. In this respect, interventions are not about knowing and performing methods but the PT’s perception, understanding and anticipation of the child’s bodily expressions and motor intentions.4.The enactive approach combines epistemological and ontological concerns of sensorimotor life, allowing us to conceive children as autonomous, adaptive embodied agents by viewing the relationship between the child’s mind–body and the world as dynamic, temporal, and co-evolving. In that respect, the enactive approach offers PTs and other health professionals integrated insights from various theoretical fields, as they relate to the development of motor control and skill acquisition. The enactive approach offers an alternative perspective to guide and comprehend clinical practice from the perspective of the child through participatory sensemaking. Our aim was not to highlight one theoretical position over another but rather to present the common principles of contemporary frameworks of motor control and to expand them by incorporating an enactive understanding of the child as an embodied agent in the world. We believe that our recommendation of incorporating an enactive embodied view to therapy offers an innovative approach to practice and provides PTs and other health professionals the opportunity to challenge established ways of thinking and practicing. Finally, we would make clear that these embodied concepts should be understood as ongoing processes and can be integrated into clinical encounters with patients of any age.The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.MS and GKØ were responsible for the conceptualization of the manuscript. Additionally, MS drafted and prepared the figures. All authors contributed to the preparation of the first draft, to the review and revision of the manuscript, approved the submission, and are accountable for all aspects of the work.


The purpose of the paper is to check whether the introduction of the VAR system mitigated the referee bias against away teams. The dataset comprises 2279 matches played in the first tier of the Brazilian League from 2016 to 2021. We analyze 6 seasons of the first tier of the Brazilian domestic football league– 3 seasons before and 3 seasons after the introduction of the VAR technology. Potential bias is viewed through the lens of yellow cards, red cards and number of penalties awarded for both home and away clubs. A paired t-test is used to reveal potential statistical differences between pre-VAR and post-VAR periods, followed by Ordinary Least Squares regressions to inspect whether certain referee’ categories have changed their behavior after the implementation of this technology. Our empirical findings offer evidence that the referee bias is diminished, but still present. The sports field is actively popularized all over the world. Various competitions, from the Olympic Games to e-sports tournaments, are attracting more and more attention from a wide variety of groups of people: fans, sponsors, sports experts, scientists. The audience is interested in the persistent struggle of motivated athletes, based on the principles of fair sport and rivalry, when everything is determined by diligence and the will to win, and when any underdog can end up being the winner.Referees have one of the key roles in any sport. Being a direct participant of the competition, the referee, in addition to his protocol duties , must also ensure compliance with the sports rules. Since the athletes are under strong emotional stress and cannot give an objective assessment of game episodes independently, the referee is obliged to keep a cool head in any situation and be able to make unbiased decisions.This study focuses on football. The most popular sport in the world is a platform for confrontation between different groups of people pursuing their own goals and interested in a certain result of the match. Since it is much more difficult to influence the whole team than one person, these people often define the referee as the object of their pressure and try to force him to make decisions in favor of one of the parties. Even though special attention is paid to the emotional preparation and stress resistance of referees, not all of them can cope successfully with such pressure.One of the most resonant cases, when several referees were accused of bias and favoritism at once, occurred during the 2002 World Cup. The South Korean team, which co-hosted the tournament with Japan, reached the semi-finals of the tournament, where they lost to the German team. According to most experts, this was largely due to refereeing mistakes made in succession in matches against Portugal (group stage), Italy and Spain  refereeing mistakes helped South Korea to go so far, which were consistently committed in favor of the hosts of the tournament in the group stage match against Portugal, in the 1/8 finals against Italy and in the quarterfinals against Spain. After the end of the tournament, Joseph Blatter, the president of FIFA at the time, publicly criticized refereeing during the championship, pointing out several serious mistakes that had a key impact on the results of the matches. The organizers of the competition also agreed with him.The refereeing of Tom Henning Øvrebø in the 2009 Champions League semi-final between Chelsea and Barcelona stands out from other controversial refereeing in case of a single match. During the game, he had reason to appoint a penalty three times against Barcelona, but he never pointed to the 11-meter mark. As a result of the match, Barcelona reached the final of the tournament, and then won it. Øvrebø’s decisions are still being criticized by fans on social media, and the referee himself has admitted to receiving threats for several years.In January 2022, one of the most respected German referees, Felix Zweier, temporarily suspended his career due to serious moral fatigue and the need for psychological recovery. He attributed this to severe stress and the need to recover psychologically. After the match between Bayern Munich and Borussia Dortmund, the referee was severely criticized by the players of Borussia, who lost 3:2. Pointing to several controversial decisions, the players questioned Zweier’s professional suitability, recalling that he had been involved in a major match-fixing scandal a few years earlier.Regular episodes of psychological and even physical violence against referees, as well as recurring scandals caused by referee errors, have necessitated the use of new technologies in football. Until 2018, the referees, according to the rules, could not cancel the decision, whether it was a penalty kick, a missed goal, or a red card. At the same time, fans at the stadium could see replays of controversial episodes on large broadcast screens and quickly detect the referee’s mistake. In 2018, the International Football Association Board approved the use of the Video Assistant Referee (VAR) system in football matches. Its essence was that in addition to the main referee and his assistants, another team of referees also monitors the progress of the match via video broadcast. In case of controversial episodes, the VAR referee has the right to invite the main referee to the monitor and show him a video replay of the controversial situation. The chief arbiter, after consulting with a colleague, makes his final decision on the episode.From the VAR system they expected, if not the complete eradication of referee errors as a phenomenon, then at least their reduction to a minimum level and a reduction in the number of scandals. However, 4 years of the system’s operation have shown that the referees continue to make controversial and even frankly erroneous decisions, despite the possibility of a detailed study of any situation in the match using video. A big controversy erupted in March 2022 around the match Everton—Manchester City in the English Premier League, where the guests won 1–0. During the game, the ball, while in the “City” penalty area, hit the defender’s hand. According to the rules, a penalty should have been awarded. However, referee Paul Tierney, after reviewing the episode and consulting with a VAR colleague, decided not to award a penalty kick. After the match, the English Football Association recognized this decision as erroneous and made an official apology to Everton. On May 22, Manchester City became the champion of England, overtaking Liverpool by 1 point. If it had been an obvious refereeing mistake, the fate of the championship could have turned out differently.The question of whether controversial refereeing decisions are the result of random errors, or the result of systematic referee bias has formed the basis of scientific research several times not only in football, but also in other sports. Bias was analyzed through the nationality of athletes and referees, the occupancy of stadiums, and the status of rivals. Additionally, there is an ongoing debate about the use of VAR and its impacts on fairness, which several scholars have been addressing recently –3. Both The purpose of this study is to find out whether there was a bias in favor of home teams before the introduction of the VAR system, and how the situation changed after its introduction in the matches of the Brazilian football league. The main hypothesis of the study was formulated as follows: in the matches of the Brazilian football league during the period under review, there is a refereeing bias in favor of home teams in terms of cards shown and penalties awarded. To achieve this, we compared two periods: pre-VAR (2016–2018) and post-VAR (2019–2021). By doing so, we aimed to evaluate the effectiveness of VAR’s introduction in promoting referee objectivity and enhancing fairness in the game. Furthermore, we can discern potential behavioral changes based on the referee category. This research contributes to a comprehensive understanding of the impact of VAR adoption on match officiation in Brazilian football. The relevance of the work is due to an attempt to compare two football periods, and to evaluate the effectiveness of the introduction of the VAR system in terms of its impact on referee objectivity.Most studies of refereeing bias in football focus on yellow and red cards, the number of penalties awarded, or stoppage time. The reasons for bias and favoritism can be different: from the referee’s personal sympathy for one of the teams to racial dislike for a particular player, but the forms of its manifestation remain unchanged.Regarding the number of cards, the main way to identify bias in this matter is to evaluate the ratio of the number of violations committed by the team to the number of warnings and removals received for it. A study on English Premier League matches between 1995 and 2002, found favoritism in favor of the home team . SimilarExamination about red cards found that the team that remained with more players was more likely to win the match . EmotionNaturally, the players do not want to earn red cards and let their team down. In order not to receive such cards, they are even ready to change their style of play, adapting to the new rules. A paper examines how card counts were affected by the introduction of a new rule prior to the 1998–1999 season requiring a direct red card for a tackle from behind without playing the ball [Penalties are another form to potentially identify referee bias. A study on the German Bundesliga matches in the 2000–2001 season found that home teams were awarded penalties 81% of the time they really should have been . The awaIn addition to the German championship, evidence of referee bias in favor of home teams on penalties has also been found in the English Premier League . After aSerie A as well [One of the main reasons for refereeing bias in relation to penalties is pressure from the stands. After examining the relationship between penalty awards and the distance from the stands to the field, authors found that referees were less likely to award mixed penalties in stadiums where fans were separated from the field by a running track . Similar as well .Experimental research examined whether the full stands and fan’s reaction to the events have an impact even on independent referees . AuthorsThe introduction of VAR technology in professional football has been a significant development in recent years, impacting the way referees make decisions during matches. Current research on VAR in football aims to explore its effectiveness, impact on the game, and potential for improving decision-making and fairness in football. There is, indeed, evidence that this technology is very accurate , which wDespite the significant body of research that has documented the existence of referee bias in various settings and the ongoing debate about the potential fairness VAR could bring to football matches, none of these studies has empirically investigated whether the introduction of VAR has actually mitigated referee bias. This gap in the literature highlights the need for further research to explore the impact of VAR on the fairness and accuracy of refereeing decisions. To address this gap, the present study aims to examine the effectiveness of VAR in reducing referee bias in football matches. By doing so, this study seeks to contribute to the ongoing discussion about the role of technology in improving the objectivity and consistency of refereeing decisions in sport.Campeonato Brasileiro Série A, began in the 2019 season. This technological innovation aimed to enhance the accuracy of officiating by allowing referees to review critical decisions such as goals, penalties, and red cards.The introduction of the Video Assistant Referee (VAR) system in Brazilian football took place in a quarter-final match of the Brazilian Cup in 2018. However, the VAR’s integration into the top-tier league, For the present study, we compiled a panel dataset comprising data from 2,279 matches in the Brazilian Serie A (first tier) across the seasons from 2016 to 2021. Our aim was to establish a balanced panel, dividing the dataset into two equal periods of three seasons each. The primary objective is to investigate potential variations in the allocation of yellow and red cards, as well as penalty kicks, by referees for both home and away teams between these distinct timeframes. Given the objective of enhancing fairness in the game through the introduction of VAR technology, we empirically assess its impact within the context of Brazilian football. The dataset is available as a Supporting Information file.The empirical strategy initiates with a paired t-test, a statistical method comparing the averages of yellow cards, red cards, and penalty kicks before and after the introduction of VAR. This test assesses whether there are statistically significant differences in these indicators between the two periods. A significant result implies that there was a notable change in referee decisions, with the direction of change determined by the sign of the t-statistic. For instance, a negative t-statistic indicates a decrease in card or penalty kick assignments, while a positive t-statistic suggests an increase.R), control variables (CV), and the outcomes of interest , these models provide insights into the impact of VAR on referee decisions. The coefficients  associated with referee categories in these models will indicate whether and to what extent certain referee groups adjusted their officiating tendencies in the post-VAR period. The general models are presented below:Later, panel data Ordinary Least Squares (OLS) regressions are carried out. These econometric models aim to reveal whether specific referee categories altered their behavior following the introduction of VAR. By examining the relationships between referee categories (Where:i = a given matcht = a given seasonR = matrix of referee categoriesCV = control variablesεit = error termy), red cards (r), and penalty kicks (p). All models were regressed using identical sets of explanatory and control variables, which allows comparisons between them. The variables of interest are in the matrix of main referee categories (R). Main referees are sorted into three categories: CBF, MTR and FIFA, from the least to the most experienced ones. The first group is used as base/reference category in the equations. Our goal is to check whether referees from any of these categories have changed their behavior after the introduction of VAR.Three dependent variables are regressed: yellow cards (CV) to enhance the precision and reliability of our analysis. These control variables, including referee age, square difference in the win probabilities of home and away team, league table positions for both home and away teams, and average statistics such as yellow cards, red cards, and penalty kicks assigned to the home team in previous matches, serve multiple crucial purposes. Firstly, they aid in the mitigation of potential confounding factors that may influence the allocation of decisions by referees. Secondly, these variables allow us to isolate and estimate the specific impact of VAR introduction on referee bias while accounting for extraneous influences. Additionally, fixed effects for both home and away clubs, as well as referee fixed effects, are integrated into the modeling to control for unobservable characteristics unique to the home and away clubs and individual referees. These fixed effects are integrated into the modeling to also mitigate potential confounding effects arising from the influence of these factors on the observed outcomes, ensuring the reliability of the model’s estimates.We incorporate several control variables  for home teams and -1.49 (p = 0.1351) for away teams.In terms of penalty kicks, home teams saw an increase in the mean number of penalties awarded from 0.12 in the pre-VAR period to 0.15 in the post-VAR period, although this difference was not statistically significant . Similarly, away teams experienced a slight increase from 0.08 to 0.10 in the mean number of penalty kicks, with weak evidence of a potential difference . The observed increase in the mean number of penalties for both home and away teams, although not statistically significant (only at 10%), may indicate a tendency toward a higher number of penalties being assigned in the post-VAR period. Referees now have the support of VAR to identify penalty kicks and reconsider their initial decisions, which could contribute to this observed trend.Overall, the introduction of VAR appeared to have a more pronounced impact on the number of yellow cards, leading to a statistically significant decrease for away teams. However, the effects on red cards and penalty kicks were less evident, with no significant changes observed for home teams and only weak indications of potential differences for away teams. It is essential to consider these findings within the broader context of VAR’s influence on disciplinary actions in football matches.In order to further examine the potential factors influencing the observed changes in disciplinary actions following the introduction of VAR, we conducted Ordinary Least Squares (OLS) regression analyses. Our aim was to explore whether specific referee categories played a significant role in driving these changes. By examining the impact of referee characteristics, we can gain insights into whether certain groups of referees were more inclined to adapt their officiating style in response to VAR implementation.We performed a total of 12 regression models. There are three dependent variables , which were regressed twice–pre-VAR and post-VAR introduction–for both home and away clubs. The estimators MRC = FIFA and MRC = MTR represent different referee categories and provide insights into their influence on disciplinary actions. In the pre-VAR period, FIFA referees were assigning significantly fewer yellow cards to home teams than their counterparts (MTR and CBF). No differences in red cards and penalty kicks are observed. However, after the introduction of VAR, both FIFA and MTR referees assigned statistically fewer yellow cards to home teams than the base category–the less experienced referees. Additionally, MTR referees have also shown a significantly reduced number of red cards.Regarding the cards and penalty kicks assigned to away teams, one can notice that the only statistically significant variable is the yellow cards in the pre-VAR period, which indicates that the most experience referees have been showing a fewer number of yellow cards to away teams than their counterparts. Nonetheless, after the introduction of the VAR, such a difference is no longer observed, implying that all categories are currently refereeing at similar manner.natural experiment, we ran paired t-test to reveal potential statistical differences between pre- and post-VAR as well as regression models to check whether certain referee categories would be influencing the potential changes.Overall, the average numbers indicate some differences in all three variables analyzed. Brazilian referees tend to show fewer yellow and red cards to home teams than to away teams, as well as award a higher number of penalties to home than away teams. It could be interpreted as some sort of referee bias–indeed, it has been previously detected in Brazil, where referees consistently exhibited a bias in favor of home teams by allocating additional time in closely contested matches when the home team was losing . NonetheOur empirical results indicate that after the introduction of VAR, away clubs have been awarded a fewer number of yellow cards, which might be interpreted as a sign of a mitigation of referee bias. Since the referee’s performances are now under larger scrutiny, this external pressure could be driven to less biased behavior against away teams, which lead into a reduced number of yellow cards to those teams. On the other hand, the introduction of this new refereeing technology did not imply a significant change in the number of red cards assigned, although there is some evidence that the number of penalty kicks have slightly increased for both home and away clubs. We assume that the opportunity to revise such controversial moments may have contributed to this higher number of penalties observed.Former study discusses VAR as an accurate tool for decision-making on football , but theIt should be noted that most of the VAR period discussed in the article coincided with the time of the Covid-19 pandemic, which potentially changed the way sports competitions were held around the world. For almost one and a half seasons, the matches were held in empty stadiums, and therefore the pressure on the referees was greatly reduced from the fans. Some recent papers show that empty stadiums have reduced referee bias on football –26, whilLastly, it is important to acknowledge that our analysis of potential referee bias has primarily focused on yellow and red cards, as well as penalty kicks. While these are significant indicators, professional sports involve numerous on-match elements that could potentially contribute to bias. However, due to the scope of a single paper and lack of available data, we have not explored these other factors comprehensively . Further research is essential to identify potential negative behaviors towards participants and, equally important, to develop strategies to mitigate unfairness within professional sports.This research examined the existence of referee bias on Brazilian football and whether the introduction of VAR on professional football has reduced such bias through a reduction on the number of cards and penalties earned by home and away teams. In a nutshell, the empirical results indicate favorable decision-making from referees towards home teams but show evidence that it has been slightly mitigated after the introduction of the VAR technology, particularly reducing the number of yellow cards awarded to away teams.We acknowledge that our econometric model cannot identify the reasons for the reduction of the bias. The support provided by the video referee is likely to impact such decline, but other elements might be shaping it. The psychological pressure that referees are facing now–due to a large coverage of their actions–could be a potential explanation for a more careful refereeing style. Further research inspecting a longer dataset is encouraged. Moreover, the analysis of similar features in different scenarios  shall be able to offer a more conclusive picture of the potential of VAR in mitigating referee bias.In conclusion, reducing referee bias in football is a complex task that requires a multifaceted approach. Our findings suggest that increasing transparency in all aspects related to the work of referees could potentially reduce errors and scandals. For instance, introducing post-match interviews with VAR referees and their assistants to explain the rationale behind their decisions publicly could increase the trust of fans about referees’ decisions. Additionally, strengthening the sanctions for gross errors can be a powerful mechanism for referees to double-check their decisions and resist pressure from the stands. In addition, educating and training referees to better understand and manage their biases can also be a valuable tool in the fight against referee bias. Further research in this area can provide additional insights into the nature of referee bias and effective strategies for addressing it.S1 Data(XLSX)Click here for additional data file.


In recent years, numerous dermatological image databases have been published to make possible the development and validation of artificial intelligence-based technologies to support healthcare professionals in the diagnosis of skin diseases. However, the generation of these datasets confined to certain countries as well as the lack of demographic information accompanying the images, prevents having a real knowledge of in which populations these models could be used. Consequently, this hinders the translation of the models to the clinical setting. This has led the scientific community to encourage the detailed and transparent reporting of the databases used for artificial intelligence developments, as well as to promote the formation of genuinely international databases that can be representative of the world population. Through this work, we seek to provide details of the processing stages of the first public database of dermoscopy and clinical images created in a hospital in Argentina. The dataset comprises 1,616 images corresponding to 1,246 unique lesions collected from 623 patients. In this context, researchers have demonstrated that a convolutional neural network, an algorithm commonly used for automatic image processing, could achieve performance on par with specialists in skin cancer identification5. Moreover, a systematic review and meta-analysis of studies comparing the outcomes of AI models and those of healthcare professionals, concluded that the diagnostic performance of AI models was equivalent to that of caregivers in several specific use cases6.Recent years have witnessed an increase in the development of Artificial Intelligence (AI) algorithms for automated medical image analysis. One of the medical specialties in which AI has been widely explored is dermatology9. However, several studies have pointed out the need for more transparency and completeness in reporting demographic information in these databases12 and in describing AI developments13. Furthermore, a systematic review of the major dermatologic imaging databases used for AI research14 revealed an uneven geographic distribution and thus limited representation of the diversity of the global population, which may result in what is referred to as health data poverty. This concept describes the hindrance that specific individuals or groups face in benefiting from innovations and research due to the scarcity of representative data15.The development and assessment of AI algorithms have been made possible in large part by the work of the scientific community to build and make public high-quality databases16. At a time when there is enormous interest in implementing clinical decision support systems (CDSS) to assist clinicians, the need to ensure algorithmic fairness has risen to the top of the agenda since the introduction of tools that work inadequately for some people may constitute a potential harm17.For multiple reasons, this situation has been pointed out as problematic by the medical image computing (MIC) community. First, it is known that training algorithms with databases made up of a few specific groups defined by attributes such as sex, age, origin, ethnicity or socioeconomic level, has given rise to what is known as algorithmic bias, also characterized by low performance of these models in the case of minorities18. In this sense, it is not possible to evaluate the performance of the methods or for them to learn specific characteristics of those sub-populations that are not represented in the databases. As a consequence, when the developments are intended to be deployed in left-out populations, the creation of new datasets, usually isolated and unpublished, becomes necessary19.On the other hand, there is evidence that the performance of AI algorithms decreases when tested on populations different from those used to train them23. Secondly, our greatest contribution lies in publishing the first anonymized dataset of clinical and dermoscopy images of skin lesions collected entirely in Argentina and the first of its kind in Hispanic America. The database was meticulously audited by experts from the Department of Dermatology of Hospital Italiano de Buenos Aires (HIBA), a highly complex hospital located in Argentina, and following the recommendations found in the literature. A similar project was conducted by the neighboring country of Brazil, in which they published a carefully refined database of clinical images24. However, the sociodemographic and epidemiological differences between our populations encouraged the conduct of this work to ensure the representativeness of the Argentinean people and their particularities in dermatological image archives. We also hope to encourage other Latin American countries to become involved in this type of endeavor to facilitate the translation of new technologies to clinical settings in the region.Based on the above, our team sought to collaborate with two lines of action. First, designing a skin lesion image database that includes metadata using the criteria defined by the International Skin Imaging Collaboration (ISIC), which aims to promote and facilitate the use of digital skin imaging to combat skin cancer. We accompany the database with this article, which aims to provide detailed information on the processes of design, compilation, and refinement of this database, as well as the description of its final content, to ensure the necessary transparency demanded by the community through different initiatives, guidelines, and frameworksThe dataset described here was composed of information collected from 623 patients seen by expert dermatologists at HIBA. We included 1,616 images  captured from 1,246 lesions corresponding to the most frequent diagnoses observed at the institution.The Institutional Review Board of HIBA approved the studies to develop AI models for skin lesion classification and evaluate them using a local database , following which the release of the de-identified local dataset was approved. The IRB approved the publication of the images along with the annotations under a Creative Commons Attribution (CC BY) license, which allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator. Because this study used secondary databases and did not modify the usual practice of the patients involved, the IRB waived the right to consent. Data preparation was carried out in compliance with the data circuit to ensure de-identification and the protection of personal data.HIBA is a community-based tertiary care hospital in Buenos Aires, Argentina. This project was conducted by the Dermatology Department and the Artificial Intelligence and Data Science in Health program of the Health Informatics Department of the institution.The following subsections describe the steps involved in the construction of the database.To populate the database we retrieved from the institutional records information collected between 2019–2022 regarding patients with common skin lesions who consulted the Dermatology Department, as well as clinical and dermoscopy images acquired at the time of the consultation. The cases included in the database were selected by three expert dermatologists.25, based on the subject’s physical characteristics. A visual examination of the patient’s skin lesions was performed, and photographs of clinically relevant lesions were acquired. Clinical images were taken through the smartphones of the respective professionals. In contrast, dermoscopy images were acquired using a video microscope VL-7EX II  and Dermagraphix Mirror 7 , a Camera Medicam 1000 s and Vexia with FotoFinder Universe 2 , a camera Medicam 800Hd attached to a dermoscope manual tower with FotoFinder 2007  or by resorting to a dermoscopic attachment for smartphones.During the anamnesis, the specialists asked patients about their personal and family history of melanoma and other personal data. In addition, they recorded the patient’s skin tone employing the Fitzpatrick scaleThe anatomical location and presumptive diagnosis were recorded for each lesion. In case of suspicion of malignancy, the professional indicated the removal of the lesion by surgical procedure and its subsequent histopathological analysis. The definitive diagnosis of these lesions was defined after knowing the result delivered by the Department of Pathology of the institution.https://www.project-redcap.org/) to form the database. In this regard, patients with at least one photographed skin lesion corresponding to malignant melanoma (MM), basal cell carcinoma (BCC), squamous cell carcinoma (SCC), actinic keratosis (AK), melanocytic nevus (NV), seborrheic keratosis (SK), solar lentigo (SL), lichen planus-like keratosis (LK), dermatofibroma (DF) or vascular lesions (VASC) were included. Cases of suspected malignant lesions without histopathological analysis performed at the institution were excluded.The patients’ personal and clinical information, as well as the biopsy results, were validated with the data recorded in the EHR. This information and the images were uploaded to a REDCap platform version 10.6.7 , each of the records in the REDCap platform was reviewed and contrasted against the institutional records to identify inconsistencies. In each case, age was approximated to the date of image acquisition and rounded to 5-year intervals to ensure data de-identification. The fields were identified as missing data in case of missing, incorrect, or doubtful information.Each patient and image was assigned a consecutive and unique alphanumeric identifier. The lesions were numbered sequentially for each patient. Finally, all information was translated from Spanish to English.27 at the following link 10.34970/587329 and was released under a Creative Commons Attribution (CC BY) license. The images, as well as a metadata table, can be downloaded from the repository. However, since it is not possible to access the unstructured data in this way, we have included this same data table with additional information regarding skin type as a The dataset described here is permanently accessible to the public through the ISIC ArchiveImages were uploaded to the archive in JPEG format and the associated metadata was shared via a comma-separated values (CSV) file. Each record in the metadata file contained a file name, a unique lesion identifier, and an anonymized patient identification number. Regarding the patient, personal and family history of melanoma, biological sex, approximate age at the time of image acquisition, and skin tone were also included. In addition, the corresponding diagnosis, the method by which it was confirmed, a benign/malignant label, and the general anatomical site where the lesion was found were incorporated. Finally, it was indicated whether it was a clinical or dermoscopy image, the type of dermoscopy if applicable, and the geographic region in which this dataset was formed.The original set of 1,755 records was thoroughly reviewed and 139 images were eliminated in this process. As a result, 43 lesions and 26 patients were excluded from the collection. The final database consisted of 1,616 images, of which 1,270 cases were contact-polarized dermoscopy images and 346 were clinical images. Each patient could have more than one skin lesion and several images per skin lesion. The dataset was formed with data collected from 623 unique patients and 1,246 unique lesions.All patients included in the database had to have attended at least one medical consultation at the hospital located in Buenos Aires, Argentina. The age was not recorded for a percentage of less than 1% of the total patients, and the mean age was 62.1 ± 17.3 years old. Regarding sex, this information was not recorded for only two patients, while the rest of the cohort corresponded to 339 females and 282 males.It was considered important to incorporate skin tone information, as this data could be retrieved from the institutional records for 566 patients . This implied that the skin tone is detailed for more than 93% of the records (images) that make up the database.In relation to the personal and/or family history of MM, multiple missing records were found, reaching 333 patients for whom neither of these two fields was recorded. With regard to personal history of MM, it was found that in 54.41% of the cases this data was not reported, while in 24.08% there were previous findings of MM and in the remaining 21.51% there were none. On the other hand, for 61.96% of the patients there was no information about a family history of MM, although of the remaining proportion, 4.98% acknowledged having family members with identified MM and 33.06% denied the existence of a family history of this type. Only 1.12% of the dataset cases had a positive personal and family history of MM.28. The number of lesions, image type distribution and percentage of biopsied lesions concerning the different diagnosis are depicted in Table Each patient was represented by at least one lesion, with the mean number of lesions per patient being two, and with one patient reaching a maximum of 63 lesions included in a study. Likewise, each lesion had at least one dermoscopy or clinical image, with cases in which both images were available. The maximum number of dermoscopies captured for a lesion was five, while the upper limit for clinical photographs was two. In general, dermoscopies were recorded more often than clinical images, as a consequence of the usefulness of the formers for the diagnosis of skin lesionsRegarding the location of the lesion, eight general anatomical sites were reported: lateral, anterior and posterior torso, lower and upper extremities, head/neck, palms/soles and oral/genital. Melanocytic lesions (MM and NV) were found to be mainly concentrated in the posterior torso, anterior torso and lower extremities, while BCC, SCC, AK and SL were most frequently located in the head or neck. Almost all of the DF were from the lower extremities, while the majority of VASC and SK came from the anterior torso in addition to the head/neck region. The set contains one LK lesion, which was photographed on the posterior torso.All images and lesions included in the dataset were thoroughly reviewed by dermoscopy experts. The histopathological analysis results report determined the definitive diagnosis of all malignant lesions. Moreover, for benign lesions there was a variable percentage of diagnoses confirmed in this way. Non-biopsied lesions were labeled based on the evaluation of the treating dermatologic expert or consensus among a group of professionals. Ultimately,24 and HAM100008, with 58.4%  and 53.13%  images with biopsy confirmation, respectively. Melanoma in situ and invasive melanoma were both identified as melanoma. Although actinic keratosis is often considered a precursor of squamous cell carcinoma, in the dataset this lesion was labeled as benign.58.18% (N = 725) of skin lesions in the dataset were biopsy-proven, which corresponds to 1,036 images or 64.11% of the complete collection. This resembles the values found in other datasets such as PAD-UFES-2030.Practitioners uploaded the metadata during patient anamnesis and subsequently retrieved it from the information recorded in the EHR. Of these data, those with the possibility of varying over time (age and history) were approximated to the date of acquisition of the image included in the dataset. On the other hand, in the vast majority of cases, skin tone was recorded by the dermatology specialist in charge of the patient considering skin tone, eye tone and the patient’s own responses to the skin’s reaction to sun exposure. In a low percentage of cases where this information was not recorded in the institutional records, dermoscopy experts evaluated the sufficiency of the dermoscopy image to infer this information from the characteristics and colors of the melanocytic neviTo our knowledge, this is the first database of clinical and dermoscopy images of skin lesions collected and made publicly available by a highly complex hospital in Hispanic America. While the database can be combined with larger image collections and used to train AI algorithms, its use is valuable in evaluation and validation processes, as well as for the comparison of different AI systems.33. The underrepresentation of South American, African and Asian populations in international databases may be the result of the lack of funding for research, the time required to collect and process these data, the demand in terms of human resources, ethical and regulatory aspects, as well as technological limitations in some health centers17. There are more complex systemic and structural reasons, such as restricted access to the health system and deep economic inequalities17, which call for different agencies to take measures to avoid falling into health data poverty. This situation is more pronounced in countries classified as lower-middle and lower-income economies.This initiative arose from the interest in implementing AI tools as support systems in institutions in our country and from the need to validate in our population algorithms created with databases from countries in North America, Europe or OceaniaThrough this project, we intend to make this situation visible, promote the construction and open access publication of databases from different regions of the world, and encourage involvement with international efforts such as the ISIC Archive. We also hope to contribute to the MIC community investigating problems such as domain shift and algorithmic bias.33. We consider that the variability in terms of acquisition equipment used, illumination conditions, resolution and the existence or not of artifacts approximates the application context in which these types of tools would be deployed. However, the use of techniques for color normalization and consistency, detection and precise localization of lesions, elimination of artifacts and treatment of class imbalance, among others, is recommended.The dataset shares features common to other dermatologic image sets such as the different diagnostic categories collected and their relative frequency, the percentage of lesions with biopsy-proven diagnosis, and the publication of the images without the application of preprocessing except for cropping to facilitate identification of the lesion of interestWithin the limitations, we understand that a selection bias could arise due to the preference to include in this database cases from institutional records that were useful for the purposes of a research and innovation project whose main objective was the development of AI models for use in a hospital located in Buenos Aires, Argentina. In this sense, the images were selected based on the diagnoses of interest, excluding multiple categories usually photographed in the clinical setting and excluding data that could have identifying components such as faces and tattoos. Moreover, as all images are from patients who attended the hospital located in Buenos Aires, this data set does not reflect the diversity of the population throughout the country. This may impact the distribution of the different classes of skin lesions and may not reflect the actual prevalence observed in clinical practice. Furthermore, we are aware that clinical and dermoscopic imaging pairs have not been provided for all lesions incorporated in this set.Finally, we consider that this is a first step towards the construction of a collaborative database with different medical centers in the country and even with other healthcare providers in the region in order to constitute a truly diverse initiative to try to guarantee our population access to state-of-the-art technology.Supplementary Table


Antenatal Education equips parents with knowledge for safe maternal health and infant care. It also reduces fear and anxiety during childbirth. ANE curriculum can vary according to country and institute. It can include classes focusing on childbirth, pain relief techniques, mode of birth, parenting, breastfeeding, breathing techniques, etc. Although ANE is widely practiced in developed countries, there is no standard program in developing countries like Pakistan. This study aims to improve antenatal education at a tertiary care hospital in Karachi, Pakistan potentially proposing an upgraded curriculum as a national standard.rd phase involved IDIs (in depth interviews) from health care workers (Obstetrics experts) to understand their perspectives regarding the ANE and the conducted classes. For phase one, gaps were identified and reported theoretically. For phase two, the annual attendance was recorded and participants’ satisfaction with the classes assessed. Qualitative data from phase 2 and 3 was converted into themes and sub-themes.This multiphase study used mix-method design was conducted in the Obstetrics and Gynaecology Department of a tertiary care hospital of Karachi, Pakistan from 2019 to 2021. Phase 1 of the study included reviewing and comparing the hospital’s antenatal curriculum with existing literature, followed by Phase 2, which was a desk review of attendance and patient feedback. The 3The audit showed a decline in the attendance of antenatal classes due to the pandemic and consequent shift to online sessions. The low attendance in online courses could be attributed to various factors. Patient feedback was generally positive, with a majority expressing high satisfaction levels. Expert feedback highlighted the need for additional topics such as mental health and COVID in pregnancy, as well as fathers' involvement. The curriculum was updated to include these topics and made more interactive with printed handouts for parents.A standardized antenatal education covering various topics surrounding pregnancy, childbirth, and postnatal care must be available to parents nationwide. Pregnancy is a time of significant physiological and emotional change, and childbirth remains a source of great fear and concern for a woman having a baby , 2. InadThe curriculum components for antenatal classes can vary according to country and institute. It can include classes focusing on childbirth, pain relief techniques, mode of birth, parenting, breastfeeding, breathing techniques etc. . FurtherAntenatal education has been extensively researched to have a significant positive impact on maternal health and practices. Apart from the apparent impact of decreased anxiety and fear of childbirth and improved confidence and self-sufficiency of mothers, studies have also established an impact on the mode of delivery with antenatal classes leading to decreased cesarean birth rate , 8, 9. MANE is considered an essential component of holistic antenatal care, steadily gaining traction globally. It has been an established as a standard practice in the developed world for years and is slowly being adopted by the developing world. The World Health Organization (WHO) has recommended antenatal education as a priority intervention to improve birth readiness and preparedness, especially in developing countries , 14. HowIn Pakistan, the availability of structured antenatal education is limited to private-sector hospitals, where often, it is integrated into routine checkups instead of well structured educational sessions. The government of Pakistan has implemented a commendable door-to-door program for maternal education, where lady health workers provide antenatal counseling. However, the program does not follow a comprehensive standardized curriculum.Dissemination of antenatal education must be dynamic, constantly evolving to meet the needs and expectations of pregnant women. This quality improvement project aims to evaluate the antenatal education being provided in the leading tertiary care hospital of Karachi, Pakistan, for its adequacy and up-to-datedness and upgrade it as required. In doing so, we also aim to lay the groundwork for a comprehensive antenatal curriculum for hospitals nationwide.An Antenatal Education curriculum-based mixed-methods design was used. The study consisted of three phases with quantitative and qualitative data collection simultaneously. Phase one featured a review of the curriculum and its comparison to other curriculum; phase two involved a desk evaluation of attendance and patient feedback documents and phase three entailed evaluating physician perspectives on the same.The study setting was a private tertiary care hospital's Department of Obstetrics and Gynaecology (OB-GYN), a largest private tertiary care hospital in Karachi, Pakistan with 128 dedicated beds for OB-GYN conducting approximately 6000 deliveries each year .Parents attending the ANE classes and experts in the relevant field i.e., Registered Nurses (RN) and Obstetricians. Participants included who provided the informed written consent.The first phase of the audit included a desk review of all the presentations and teaching material by a team of investigators that included a qualified post graduate MBBS research fellow in maternal health stream, an antenatal nurse expert, and a full-time faculty ECD lead who is a global certified trainer in First 1000 days parenting education. The curriculum was thoroughly vetted and evaluated by the team members individually based on a self-constructed, thorough criteria involving a Likert scale grading of the the following categories: significance, ease of understanding, practical impact, authenticity, relevance of topic, and interactivity of the lesson. the next step involved consolidation of the individual assessments of the team members. For this review, people from the disciplines of women physio, genetics, lactation consultation and nutrition were consulted as needed regarding potential inaccuracies. This desk review was used to detect potential strengths and weaknesses in our ANE curriculum, and to identify the potential target areas to be addressed by the obstetric experts for improvement in the later phase of the study.The attendance records of the parents who took ANE classes were reviewed to determine the level of engagement with the curriculum. These were collected by identifying the parents with associated medical records who attended the classes and asking them for feedback if they consented. 41 graded evaluations and 25 subjective patient feedback comments were reviewed to assess the effectiveness of the curriculum. All attendees were given a feedback form to fill out at the end of the last class. This feedback included grading of level of satisfaction with various components of the antenatal classes including clarity of information, learning material, classroom environment, presentation and tour of the hospital facilities. A positive likert scale was used for grading the level of satisfaction i.e., 1 as strongly dissatisfied and 4 as satisfied.In-depth interview (IDI) guide was designed, and data was collected from two Obstetricians and two registered nurses (RNs) from the department of OB-GYN. The IDI questions focused on their perceptions of the curriculum, including the relevance of the topics covered, the effectiveness of teaching methodologies, and the usefulness of the assessments, focusing especially on the weaknesses identified in phase 1 of the study. Their input regarding any inaccuracies and recommended changes were noted. The data obtained from this phase was used to identify areas of improvement for the curriculum.The data was obtained from each phase of the study and further analyzed. For the first phase, gaps were identified and reported theoretically. Phase two analysis involved the number of participants attending each year reported and percentage for the satisfaction levels, for which, 25 patient feedback evaluations were extracted and arranged according to their subject matter. For the qualitative component, data was transcribed and translated to develop codes and later themes and sub-themes were reported. The data was analyzed using SPSS version 24 and NVivo software.The first phase of the study identified several important issues missing from the curriculum being used for the antenatal classes. The curriculum was found to be focused on labour and delivery with inadequate emphasis on lifestyle changes required during the course of the pregnancy as well as postnatal care. Topics like immunizations and follow up visits during pregnancy, postnatal contraception, appropriate storage of breastmilk and tackling postpartum depression were not addressed in the curriculum.Furthermore, the some of the presentations were found to be insufficiently patient-centred for example, explaining the stages of pregnancy and labour according to what the mother should be expecting rather than the physiological details. Furthermore, there was also a lack of appropriate referrals mentioned in the classes for example the handouts given to the participants lacked necessary information on specialized nutritionist clinics available for further guidance regarding diet and the pamphlet for the breastfeeding session missed mentioning referral to lactation clinic if required.The attendance of the antenatal classes conducted from 2019 to 2022 was compared and showed a drastic decline from 2019 to 2021  during the pandemic, educators found interacting with parents online more difficult and were second-guessing their lessons . HoweverOne of the themes that emerged from the patient feedback in our study pertained to the necessity for postnatal care education. This finding is consistent with the antenatal education being provided globally, including in developed countries. In a study conducted in Australia, new-born educators found that postnatal care and parenting advice was sought after by parents more than antenatal . Other sThe experts highly emphasized inclusion of mental health during pregnancy and postpartum. Established risk factors for postpartum depression include illiteracy, low socioeconomic status, access to healthcare and cultural stigma regarding mental health issues and lack of education are prevalent in the country , 23. NotAs mentioned by the experts, antenatal care and education in Pakistan predominantly concentrates on mothers, with little to no partner involvement. The antenatal classes being provided in our institute also had only one session of couple classes, with the rest being catered especially for mothers. However, studies have consistently shown a positive impact of increased partner involvement in antenatal care , 27. A rThis is the first ever quality improvement initiative by a teaching tertiary care university hospital in Pakistan. There are no established programs in Pakistan which tackle the antenatal education in Pakistan. This study allowed for augmentation of the education initiative being conducted at the tertiary care centre, to include previously ignored areas, and improvement of the content, structure and delivery of lessons. This study builds on the limited antenatal education being provided by the centre by comparing it to the standard in existing literature, allowing for a reliable resource to be formed, which can be used as an aid for a standardized curriculum nationwide since none exists currently. This study also used a robust method to understand the perspectives and opinions of both the parents and health care workers, allowing for maximum efficiency of the ANE, and simultaneously audited the existing curriculum to improve it.The limitations include small sample size and lack of generalizability since this study was conducted at a single centre private tertiary care hospital. Moreover, this study failed to triangulate and connect both qualitative and quantitative data.The antenatal Education curriculum should be standardized across the country that can be implemented through a hybrid approach of both online and in-person classes. This approach ensures flexibility and accessibility for all expecting parents. The curriculum should cover a wide range of relevant topics to provide comprehensive education and support throughout the antenatal period. The important components which must be included are pregnancy, foetal development, first 1000 days of life of a baby, nutrition and exercise in pregnancy, labor and modes of pain relief that are available during labour, importance of breastfeeding and basics of new-born care. These educational sessions should be delivered in way that they are interactive for the participants, should address the cultural norms and values, and should encourage participation from both the parents and not only the mother, as is seen in current practice.


The joint occurrence of diabetes and hypertension conditions in a patient is common. The two diseases share a number of risk factors, and are hence usually modelled concurrently using bivariate logistic regression. However, the postestimation assessment for the model, such as analysis of outlier observations, is seldom carried out. In this article, we apply outlier detection methods for multivariate data models to study characteristics of cancer patients with joint outlying diabetes and hypertension outcomes observed from among 398 randomly selected cancer patients at Queen Elizabeth and Kamuzu Central Hospitals in Malawi. We used R software version 4.2.2 to perform the analyses and STATA version 12 for data cleaning. The results showed that one patient was an outlier to the bivariate diabetes and hypertension logit model. The patient had both diabetes and hypertension and was based in rural area of the study population, where it was observed that comorbidity of the two diseases was uncommon. We recommend thorough analysis of outlier patients to comorbid diabetes and hypertension before rolling out interventions for managing the two diseases in cancer patients to avoid misaligned interventions. Future research could perform the applied diagnostic assessments for the bivariate logit model on a wider and larger dataset of the two diseases. This is usually the case because the two disease conditions share risk factors, which among others include old age, obesity, genetic factors, and dyslipidaemia3. Living with the two disease conditions generally affects the immune system and mental health of a patient. In particular, co-existence of type2 diabetes mellitus and hypertension in a patient is associated with poor cognitive functioning, ischemic cerebrovascular disease, retinopathy, heart disease, sexual inactivity, and kidney problems7. For patients with other chronic diseases such as cancer, presence of the diabetes and hypertension diseases is associated with poor prognosis outcomes in the patient10. Therefore, more ways of managing effects of the joint occurrence of diabetes and hypertension in cancer patients have to be explored11.Diabetes and hypertension conditions often occur concurrently in a patient13. Although this method is popular for modelling comorbidity data, the follow-up residual assessments are rarely done by researchers, mainly because the diagnostic statistics for nonlinear multivariate models are not well-developed14. This creates a vacuum in understanding the fit of the model to the bivariate data15. As for cancer patients with comorbid diabetes and hypertension, there could be some outlier patients with special characteristics, whose knowledge can help in managing joint adverse effects of the two diseases in a patient. This study therefore analyses characteristics of the outlier cancer patients with comorbid diabetes and hypertension, upon fitting a bivariate logistic regression model to the cancer patients’ data, that were randomly collected at Queen Elizabeth and Kamuzu central hospitals in Malawi. An outlier observation is one whose measurement does not conform with the rest of the data points in the fitted model15. This may be due to natural causes, which in the case of comorbid diabetes and hypertension patient data may help in revealing ways for managing impact of presence of the two diseases in a cancer patient. At times, outliers are as a result of data collection and handling errors. Whichever is the reason for outlierness, presence of outliers in a model may lead to biased estimated effects of risk factors of the diseases and inaccurate conclusions, as well as compromised policy directions from the fitted model.Since the data for observing presence or absence of either diabetes or hypertension in a cancer patient are binary, assessment of risk factors for the comorbidity of the two diseases can be done using bivariate logistic regression, a model that quantifies effects of the covariates on the joint binary outcomes, while accounting for the correlation of the two binary outcome variables11. Knowing the characteristics of outlier cancer patients with comorbid diabetes and hypertension contributes to that process. Following this section is the presentation in “Understanding cancer and allied diseases’ management approaches is an ongoing process, that requires continuous research11.The study used data for adult cancer patients aged 18 years and above, that were collected at the two major referral hospitals of Queen Elizabeth and Kamuzu Central in Malawi, by the cancer research group of Kamuzu University of Health Sciences. The project engaged a random cross-sectional sample of 398 cancer patients, that presented themselves for oncological services at the two referral hospitals between 13th January and 23rd March 2021. The study participants were selected using simple random sampling technique, and face-to-face interviews were conducted to collect the data. In addition, the patients’ health passports, registers, and files were reviewed to get the patients’ histories. The data included cancer diagnosis information for the patient, its stage and treatment options, as well as some known behavioural risk factors and socio-demographic characteristics of the patient. Further details about the project can be found in the article3. Some of the factors that are associated with comorbid diabetes and hypertension are old age, elevated cholesterol, cigarette smoking, physical activity, wealth index, occupation, alcohol consumption status, marital status, place of residence, education level, and sex of an individual17. This study included these factors during the model fitting. The research team in this project got the ethical clearance and approval from the College of Medicine Research and Ethics Committee (COMREC), certificate number P.07/20/3085. In addition, the directors at the two referral hospitals provided separate approvals to allow the team to collect the data. During data collection and analysis, patients’ identities were anonymised to maximise the patients’ confidentiality and respect their privacy. In addition, informed consent to participate in this project was obtained from all participants and/or their legal guardian(s). All methods in this study were performed in accordance with the relevant guidelines and regulations11.In this present study, interest was on identifying characteristics of cancer patients that presented outlying diabetes and hypertension measurements upon considering possible risk factors of both diseases in a regression model set up. Therefore, the outcome variables for this study were whether or not a cancer patient suffered from diabetes or hypertension or both, as at the time of the survey. The two disease conditions were selected for study as they are known to occur jointly in a patient in most casesn observations, expressed as follows:18. As it can be appreciated in Eq.  is the signum function of the residual 19. We assessed this graphically by plotting the marginal deviance residuals in Eq. , we , we 5), 11.The study was part of the Kamuzu University of Health Sciences cancer project, whose data were collected with approval of the College of Medicine Research and Ethics Committee (COMREC). The ethical approval certificate is numbered P.07/20/3085. Subsequent approvals were also given by the respective directors at Queen Elizabeth and Kamuzu Central hospitals. The three approval letters have been submitted together with this manuscript. All ethical considerations for the patients were adhered to during data collection, analysis and reporting of this study. Informed consent to participate in this project was obtained from all participants and/or their legal guardian(s). All methods in this study were performed in accordance with the relevant guidelines and regulations. More details on ethical clearance for the project are provided in the articleThe summary of the data is given in Table The estimates from a bivariate logit model with non-exchangeable covariates effects on diabetes and hypertension outcomes are given in Table The results in Table The plots of marginal deviance residuals against respective fitted probabilities in Fig. mentclass2pt{minimmentclass2pt{minimmentclass2pt{minimmentclass2pt{minimUnlike with the non-exchangeable marginal models, the residual results for exchangeable marginal models in Fig. The plots of overall deviance residual against marginal fitted probabilities for non-exchangeable bivariate logit model in Fig. Similarly, when the overall deviance residual for the non-exchangeable model was plotted against marginal deviance residuals in Fig. Now, using the cutoff Finally, index plots of the overall residual in both non-exchangeable, Fig. Chikwawa district. The outlier patient was a married Christian, with middle wealth index, minimum of secondary education, and was a retired employee as at survey time. She suffered from cervical cancer, that was diagnosed in 2018 as a localised disease. She had since received chemotherapy treatment and underwent surgery. The outlier cancer patient suffered from both diabetes and hypertension diseases, as well as HIV/AIDS, but had no any heart, liver, nor respiratory related complications. She also had no history of tobacco smoking nor alcohol drinking. The data showed that she had problems with walking about, felt moderate pain and discomforts, and had problems with performing usual activities, such as household chores or study.Upon tracking the identified overall outlier observation number 172 in the main dataset, the results showed that this was a female aged 43 years, who weighed 61 kgs and resided in rural area in 7. In most cases, the next step after identifying outliers is to assess their influence on the model’s estimates, which is usually done by re-fitting the model to data without the outlier observations in the sample and observe the changes in the ML estimates or by applying appropriate influence statistics to examine influence of each observation on ML estimates25. We did not perform such analysis in this study, as the goal of the paper was on detecting and understanding characteristics of the outlier cancer patients to comorbidities of diabetes and hypertension, so as to establish the reasons for outlierness in order to recommend appropriate ways for managing the two diseases in such type of patients, without necessarily improving the model.In this article, the postestimation techniques for the bivariate logistic regression model were applied to analyse outlier cancer patients that had comorbidities of diabetes and hypertension at Queen Elizabeth and Kamuzu central hospitals in Malawi. The study identified one overall outlier patient to the two diseases’ model. The detected outlier patient was a female with cervical cancer and based in rural area, who suffered from both diabetes and hypertension. She was married and educated, with age of 43 years and moderate weight of 61 kgs. The outlier patient had no smoking and alcohol drinking history. Since this study observed that co-occurrence of diabetes and hypertension was rare for rural populations, it was therefore not surprising for the bivariate logit model diagnostic statistics to detect this rural resident as an outlier to the model26. This could be as a result of smallness in sample size that was used. The HDE usually masks the true effect of a covariate on a binary outcome as though it does not exist, and this can be corrected by using alternative tests for assessing usefulness of covariates in a logit model, such as likelihood-ratio test instead of the Wald test24. The likelihood ratio test analyses usefulness of a covariate by comparing the likelihood estimates with and without the particular covariate in the model. However, this method requires re-fitting the model to data upon removing the concerned covariate, which can be cumbersome for non-linear models, such as the bivariate logistic regression model, that engage iterative numerical techniques like Newton–Raphson method to estimate parameters27. Hence, this study used the Wald test to analyse significance of covariates, due to its computation efficiency. Although the p-values realised from the models were large, this study proceeded with joint outlier analysis to the bivariate logit model because outlierness of an observation is relative to others in the fitted model25, no matter the level of fit of the model at hand.This study has observed that the exchangeable bivariate logit model fitted the data better than the non-exchangeable model. The data provided evidence of dependence between diabetes and hypertension diseases in a person. Based on the exchangeable model, suffering from diabetes was less likely to happen compared to hypertension in a patient. This may reflect the nature of the sample that was used, which had too few diabetes cases. The Wald test for evaluating significance of each covariate in the fitted bivariate logit model suffered from the Hauck–Donner effect (HDE) in this study, in which the test value tends to zero when the distance between the ML estimate and hypothesised value widens up, which rendered the p-values for the ML estimates to be unrealistically larger than expected or to be not applicable for variable selection analysis30. The general consensus in literature is that statistical insignificance should not override clinical significance31. It is for this reason that this study included all the affected variables during the Chi-Square tests when fitting the bivariate logit model to the data to analyse outlier cancer patients.The small sample size used in this study might have also affected Chi-Square test results in the cross-classification analysis, where some variables were observed to have insignificant association at 5% significance level with either diabetes or hypertension. However, the Chi-Square p-values for the affected variables were still far lower that 1, which indicated existence of some association, at higher levels of significance than 5%, between the concerned variables and diabetes or hypertension. These results add to the debate on whether researchers should prioritise statistical significance over clinical significance for studies that involve some medical data3.Finally, the study observed that there was high likelihood for female, the married, the educated, and persons with smoking and alcohol drinking history to suffer from either diabetes or hypertension. The diseases were less likely to affect the rural compared to urban populations. These results were consistent with literature, that attributes fancy lifestyle in the indicated populations as a source for increased riskThis study sought to assess joint outliers to comorbidities of diabetes and hypertension through fitting a bivariate logistic regression model to the cancer medical data in Malawi. By applying diagnostic statistics for multivariate data models, we effectively examined outliers to the fitted bivariate logit model. The methods identified one outlier cancer patient to diabetes and hypertension outcomes, whose main unique feature was being based in rural area, where the two studied diseases were rare. We recommend careful analysis of outlying patients to comorbid diabetes and hypertension, through regression methods that should precede drafting of policies for managing the two diseases in cancer patients, in order to avoid misaligned interventions.Further, the model estimates in this study confirmed previously-observed risk factors for comorbidities of diabetes and hypertension. The most vulnerable groups were females, the educated, past smokers and drinking groups, and the married. The exchangeable bivariate logit model produced better fit compared to the non-exchangeable model. Therefore, assuming that the available covariates affect either marginal outcome in the bivariate logit model could give the researcher accurate estimates, when using limited data. There are a number of risk factors for comorbid diabetes and hypertension, that are reported in literature but were not part of the dataset used in this study, moreover the sample was small which affected convergence of estimates such as the p-values. Future research could apply these statistical methods on a wider scale dataset.