To vaccinate or not to vaccinate? The interplay between pro- and against- vaccination reasons.

BACKGROUND: By mid 2023, European countries reached 75% of vaccine coverage for COVID-19 and although vaccination rates are quite high, many people are still hesitant. A plethora of studies have investigated factors associated with COVID-19 vaccine hesitancy, however, insufficient attention has been paid to the reasons why people get vaccinated against COVID-19. Our work aims to investigate the role of reasons in the decision to get vaccinated against COVID-19 in a representative sample of 1,689 adult Italians (March-April 2021) balanced in terms of age, gender, educational level and area of residence. METHODS: Through an online questionnaire, we asked participants to freely report up to three reasons for and against COVID-19 vaccination, and the weight each had in the decision to get vaccinated. We first investigated the role of emotional competence and COVID-19 risk perception in the generation of both reasons using regression models. Next, we studied the role that the different reasons had in the vaccination decision, considering both the intention to vaccinate (using a beta regression model) and the decision made by the participants who already had the opportunity to get vaccinated (using a logistic regression model). Finally, two different classification tree analyses were carried out to characterize profiles with a low or high willingness to get vaccinated or with a low or high probability to accept/book the vaccine. RESULTS: High emotional competence positively influences the generation of both reasons (ORs > 1.5), whereas high risk perception increases the generation of positive reasons (ORs > 1.4) while decreasing reasons against vaccination (OR = 0.64). As pro-reasons increase, vaccination acceptance increases, while the opposite happens as against-reasons increase (all p < 0.001). One strong reason in favor of vaccines is enough to unbalance the decision toward acceptance of vaccination, even when reasons against it are also present (p < 0.001). Protection and absence of distrust are the reasons that mostly drive willingness to be vaccinated and acceptance of an offered vaccine. CONCLUSIONS: Knowing the reasons that drive people's decision about such an important choice can suggest new communication insights to reduce possible negative reactions toward vaccination and people's hesitancy. Results are discussed considering results of other national and international studies.

Who is likely to vacillate in their COVID-19 vaccination decision? Free-riding intention and post-positive reluctance.

Despite the actual availability of COVID-19 vaccines to combat the pandemic, many people are still vacillating in their decision to vaccinate. In this study, we considered the effect of two relevant contextual issues on vaccination intention: the number of people infected with COVID-19 is increasing, and the pace of vaccination is gaining speed. Specifically, we hypothesized that having already contracted SARS-CoV-2 (post-positive reluctance) could lead people to underestimate the importance of vaccination. Moreover, as the number of vaccinated people increases, more hesitant people could fall into the free-riding intention category, benefitting from the immunity provided by others' vaccinations. Vaccine hesitancy becomes more critical as the vaccination campaign proceeds: at one point, it will be inevitable to deal with hesitant people. This study is part of a WHO Regional Office for Europe project and involved a representative sample of 5006 Italians interviewed in January-February 2021. In case of post-positive reluctance, both young age and female gender increase vaccine hesitancy, while a high level of education reduces free-riding intention. Considering post-positive reluctance and free riding, a protective effect on hesitancy is associated with negative affective states, adherence to protective behaviors, trust in health information sources, and resilience. In contrast, increased vaccine hesitancy is associated with a high level of conspiracy-mindedness and trust in media information sources. Recognizing and studying the post-positive reluctance and the phenomenon of free-riding people can help us to become more efficient in combatting the virus.

Moral judgment, decision times and emotional salience of a new developed set of sacrificial manual driving dilemmas.

The growing interest in the subject of moral judgment in driver and autonomous vehicle behavior highlights the importance of investigating the suitability of sacrificial dilemmas as experimental tools in the context of traffic psychology. To this aim a set of validated sacrificial trolley problems and a new set of trolley-like driving dilemmas were compared through an online survey experiment, providing normative values for rates of participants' choices; decision times; evaluation of emotional valence and arousal experienced during the decision process; and ratings of the moral acceptability. Results showed that while both sets of dilemmas led to a more frequent selection of utilitarian outcomes, the driving-type dilemmas seemed to enhance faster decisions mainly based on the utilitarian moral code. No further differences were observed between the two sets, confirming the reliability of the moral dilemma tool in the investigation of moral driving behaviors. We suggest that as moral judgments and behaviors become more lifelike, the individual's moral inclination emerge more automatically and effectively. This new driving-type dilemma set may help researchers who work in traffic psychology and moral decision-making to approach the complex task of developing realistic moral scenarios more easily in the context of autonomous and nonautonomous transportation.

Colonic J-Pouch or Straight Colorectal Reconstruction After Low Anterior Resection For Rectal Cancer: Impact on Quality of Life and Bowel Function: A Multicenter Prospective Randomized Study.

BACKGROUND: Patient-reported outcomes associated with different bowel reconstruction techniques following anterior resection for rectal cancer are still a matter of debate. OBJECTIVE: This study aimed to assess quality of life and bowel function in patients who underwent colonic J-pouch or straight colorectal anastomosis reconstruction after low anterior resection. DESIGN: Bowel function and quality of life were assessed within a multicenter randomized trial. Questionnaires were administered before the surgery (baseline) and at 6, 12, and 24 months after surgery. SETTINGS: Patients were enrolled by 19 centers. The enrollment started in October 2009 and was stopped in February 2016. The study was registered at www.clinicaltrials.gov (Identifier: NCT01110798). PATIENTS: Patients who underwent low anterior resection for primary mid-low rectal cancer and who were randomly assigned in a 1:1 ratio to receive either stapled colonic J-pouch or straight colorectal anastomosis were selected. MAIN OUTCOME MEASURES: The primary outcomes measured were quality of life and bowel function. RESULTS: Of the 379 patients who were evaluable, 312 (82.3%) completed the baseline, 259 (68.3%) the 6-month, 242 (63.9%) the 12-month, and 199 (52.5%) the 24-month assessment. Bowel functioning and quality of life did not significantly differ between arms for almost all domains. The total bowel function score, the urgency, and the stool fractionation scores significantly worsened after surgery and remained impaired over time in both arms (p < 0.0032), whereas constipation improved after surgery but recovered to baseline levels from 1 year onward (p < 0.0036). All patients showed a significant and continuous improvement in emotional functioning (p < 0.0013) and future perspective (p < 0.0001) from baseline to the end of the study. LIMITATIONS: Limitations of the study include missing data, which increased over time; the possibility that some treatments have slightly changed since the study was conducted; and investigators not blind to treatment allocation. CONCLUSION: The findings of this study do not support the routine use of colonic J-pouch reconstruction in patients with rectal cancer who undergo a low anterior resection. See Video Abstract at http://links.lww.com/DCR/B328. BOLSA J COLÓNICA O RECONSTRUCCIÓN COLORRECTAL RECTA DESPUÉS DE RESECCIÓN ANTERIOR BAJA PARA CÁNCER RECTAL: IMPACTO EN LA CALIDAD DE VIDA Y LA FUNCIÓN INTESTINAL: UN ESTUDIO ALEATORIZADO PROSPECTIVO MULTICÉNTRICO: Los resultados informados por el paciente asociados con diferentes técnicas de reconstrucción intestinal después de la resección anterior para el cáncer de recto aún son tema de debate.Evaluar la calidad de vida y la función intestinal en pacientes que se sometieron a una bolsa en J colónica o reconstrucción de anastomosis colorrectal recta después de una resección anterior baja.La función intestinal y la calidad de vida se evaluaron en un ensayo aleatorizado multicéntrico. Los cuestionarios se administraron antes de la cirugía (basal) y a los 6, 12 y 24 meses después de la cirugía.Los pacientes fueron incluidos en 19 centros. La inscripción comenzó en Octubre de 2009 y se detuvo en Febrero de 2016. El estudio se registró en www.clinicaltrials.gov (Identificador: NCT01110798).Pacientes que se sometieron a resección anterior baja por cáncer rectal primario medio-bajo y que fueron aleatorizados en una proporción de 1: 1 para recibir bolsa J colónica con grapas o anastomosis colorrectal recta.calidad de vida y función intestinal.De los 379 pacientes que fueron evaluables, 312 (82.3%) completaron la evaluación inicial, 259 (68.3%) a los 6 meses, 242 (63.9%) a los 12 meses y 199 (52.5%) a los 24 meses. . El funcionamiento intestinal y la calidad de vida no difirieron significativamente entre los dos grupos en casi todos los dominios. La puntuación total de la función intestinal, la urgencia y las puntuaciones de fraccionamiento de las heces empeoraron significativamente después de la cirugía y continuaron con el tiempo extra en ambos grupos (p <0.0032), mientras que el estreñimiento mejoró después de la cirugía pero se recuperó a los niveles basales a partir de 1 año en adelante (p <0.0036). Todos los pacientes mostraron una mejora significativa y continua en el funcionamiento emocional (p <0.0013) y la perspectiva futura (<0.0001) desde el inicio hasta el final del estudio.Datos faltantes, que aumentaron con el tiempo; la posibilidad de que algunos tratamientos hayan cambiado ligeramente desde que se realizó el estudio; investigadores no cegados a la asignación del tratamiento.Los hallazgos de este estudio no respaldan el uso rutinario de la reconstrucción de la bolsa J colónica en pacientes con cáncer rectal que se someten a una resección anterior baja. Consulte Video Resumen en http://links.lww.com/DCR/B328. (Traducción-Dr. Yesenia Rojas-Khalil).

A Psychological Perspective on Factors Predicting Prophylactic Salpingo-Oophorectomy in a Sample of Italian Women from the General Population. Results from a Hypothetical Study in the Context of BRCA Mutations.

The aim of this study was to assess attitudes toward ovarian cancer risk management options for BRCA mutation carriers in healthy Italian women, and to identify predictors of the preference for risk reducing salpingo-oophorectomy (RRSO) over surveillance. One hundred eighty-one women aged 30-45 completed a questionnaire about preferences, knowledge, risk perception, and socio-demographic information. Participants were randomly presented with a pamphlet about BRCA1 or BRCA2 mutation-specific testing, consequences of testing and preventive options for carriers, and they were stratified by having children or not and by age group. Surveillance was the preferred option (64.6%), followed by RRSO (24.3%). Although RRSO is the only effective strategy available to BRCA carriers, most healthy women faced for the first time with this option may not consider it as their preferred choice. Predictors associated with a higher likelihood to prefer surgery over surveillance were: knowing that life expectancy is longer with surgery, perceived comprehension of the consequences of testing, previous knowledge about BRCA testing, anticipated worry about developing cancer, and feelings of risk. Childbearing intentions and the effect of childbearing intentions on choice were associated with a lower preference for surgery. Further research is needed to confirm the role of the factors identified in this study in order to promote informed decision-making about RRSO.

Evaluation of the legal consequences of action affects neural activity and emotional experience during the resolution of moral dilemmas.

In any modern society killing is regarded as a severe violation of the legal codes that is subjected to penal judgment. Therefore, it is likely that people take legal consequences into account when deciding about the hypothetical killing of one person in classic moral dilemmas, with legal concerns contributing to decision-making. In particular, by differing for the degree of intentionality and emotional salience, Footbridge- and Trolley-type dilemmas might promote differential assignment of blame and punishment while implicating the same severity of harm. The present study was aimed at comparing the neural activity, subjective emotional reactions, and behavioral choices in two groups of participants who either took (Legal group) or did not take (No Legal group) legal consequences into account when deciding on Footbridge-type and Trolley-type moral dilemmas. Stimulus- and response-locked ERPs were measured to investigate the neural activity underlying two separate phases of the decision process. No difference in behavioral choices was found between groups. However, the No Legal group reported greater overall emotional impact, associated with lower preparation for action, suggesting greater conflict between alternative motor responses representing the different decision choices. In contrast, the Legal group showed an overall dampened affective experience during decision-making associated with greater overall action readiness and intention to act, reflecting lower conflict in responding. On these bases, we suggest that in moral dilemmas legal consequences of actions provide a sort of reference point on which people can rely to support a decision, independent of dilemma type.

Quality of life after surgery for rectal cancer.

Patients' health-related quality of life (HRQoL) is now considered a relevant clinical outcome. This study systematically reviewed articles published in the last 5 years, focusing on the impact of rectal cancer treatment on patients' HRQoL. Of the 477 articles retrieved, 56 met the inclusion criteria. The most frequently reported comparisons were between surgical procedures (21 articles), especially between sphincter-preserving and non-sphincter preserving surgery or between stoma and stoma-free patients (13 articles), and between multimodality therapies (11 articles). Additionally, twelve articles compared patients' and healthy controls' HRQoL as primary or secondary aim. The majority of the studies were observational (84 %), controlled (66 %), cross-sectional (54 %), prospective (100 %), with a sample of more than 100 patients (59 %), and with more than 60 % of patients treated with neoadjuvant therapy (50 %). The most frequently used instruments were the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (QLQ-C30), its colorectal cancer specific module QLQ-CR38, and the Medical Outcomes Study Short-Form 36 items questionnaire. Findings from the included articles are summarised and commented, with a special focus on the comparison between surgical treatments, between irradiated and not-irradiated patients, and between patients and the general population.

Moral reasoning behind the veil of ignorance: An investigation into perspective-taking accessibility in the context of autonomous vehicles.

Perspective-taking (PT) accessibility has been recognized as an important factor in affecting moral reasoning, also playing a non-trivial role in moral investigation towards autonomous vehicles (AVs). A new proposal to deepen this effect leverages the principles of the veil of ignorance (VOI), as a moral reasoning device aimed to control self-interested decisions by limiting the access to specific perspectives and to potentially biased information. Throughout two studies, we deepen the role of VOI reasoning in the moral perception of AVs, disclosing personal and contingent information progressively throughout the experiment. With the use of the moral trilemma paradigm, two different VOI conditions were operationalized, inspired by the Original Position theory by John Rawls and the Equiprobability Model by John Harsanyi. Evidence suggests a significant role of VOI reasoning in affecting moral reasoning, which seems not independent from the order in which information is revealed. Coherently, a detrimental effect of self-involvement on utilitarian behaviours was detected. These results highlight the importance of considering PT accessibility and self-involvement when investigating moral attitudes towards AVs, since it can help the intelligibility of general concerns and hesitations towards this new technology.

Moral dilemmas and moral principles: when emotion and cognition unite.

Traditional studies on moral judgement used resolutions of moral dilemmas that were framed in terms of acceptability of the consequentialist action promoting a greater good, thus overlooking the deontological implications (choices cannot be justified by their consequences). Recently, some authors have suggested a parallelism between automatic, unreflective emotional responses and deontological moral judgements. In this study, we developed a novel experimental paradigm in which participants were required to choose between two resolutions of a moral dilemma (consequentialist and deontological). To assess whether emotions are engaged in each of the two resolutions, we asked participants to evaluate their emotional experience through the ratings of valence and arousal. Results showed that emotion is involved not only in deontological but also in consequentialist resolutions. Moreover, response times pointed out a different interplay between emotion and cognition in determining a conflict in the dilemma's resolution. In particular, when people were faced with trolley-like dilemmas we found that decisions leading to deontological resolutions were slower than decisions leading to consequentialist resolutions. We propose that this finding reflects the special (but not accepted) permission provided by the doctrine of the double effect for incidentally causing death for the sake of a good end.

Framing the ultimatum game: gender differences and autonomic responses.

The present study aimed at investigating whether the way offers are framed in the Ultimatum Game (UG) affects behavioral and autonomic responses in men and women. The "I give you" and "I take" expressions were used as gain and loss frames, respectively. Skin conductance and heart rate were recorded as indices of autonomic activation in response to unfair, mid-value, and fair offers. Acceptance rates were higher in men than in women under the gain frame. Moreover, men showed higher acceptance rates under the gain than under the loss frame with mid-value offers, whereas women's choices were not affected by frame. On the physiological level, men produced differential autonomic response patterns during decision-making when offers were presented under gain and loss framing. The "I take" frame, by acting as a loss frame, elicited in men the characteristic defensive response pattern that is evoked by aversive stimulation, in which increases in skin conductance are coupled with increases in heart rate. On the other hand, the "I give you" frame, by acting as a gain frame, elicited in men increases in skin conductance associated with prevailing heart rate deceleratory responses, reflecting a state of enhanced attention and orienting. In contrast, women's autonomic reactivity was not affected by frame, consistent with behavioral results. Phasic changes in heart rate were crucial in revealing differential functional significance of skin conductance responses under different frames in men, thus questioning the assumption that this autonomic measure can be used as an index of negative emotional arousal in the UG.

Communication and shared decision-making after stillbirth: Results of the ShaDeS study.

BACKGROUND: Shared decision-making (SDM) is included in guidelines for bereavement care after a stillbirth, as it can improve women's long-term health and wellbeing. SDM within the stillbirth context is still not common, and Italy does not yet have standardised guidelines. AIM: The ShaDeS (Shared Decision-Making in Stillbirth) study aims to investigate how Italian women with a stillbirth perceive their own centrality in decision-making processes around bereavement care and how this might impact satisfaction of care. METHODS: The ShaDeS study is a cross-sectional study based on a web survey consisted of four sections: sociodemographic information and medical history, communication of bad news and bereavement care, decisions about childbirth (SDM-Q-9, SHARED, and DCS), and decisions and communication about autopsy (CPS). FINDINGS: 187 women answered the survey. For the 41.1% of women that did not have an emergency childbirth, the SDM-Q-9 median score was 66.6 (0-100 range), and the SHARED median score was 3.5 (1-5 range). 29.4% of participants reached the proposed cutoff of 37.5 in the DCS (0-100 range) suggesting a difficulty in reaching decisions. Satisfaction scores were lower for those with such difficulties (p < 0.0001). Of the 64.5% of women that discussed autopsy, 28.3% were involved in an SDM approach, despite this being associated with higher levels of satisfaction of care (p < 0.05). CONCLUSION: An SDM approach is only moderately widespread amongst our participants, despite it being significantly related to higher levels of satisfaction. Further studies should investigate the tools that both patients and healthcare professionals need for an SDM approach.

The Interplay of Perceived Risks and Benefits in Deciding to Become Vaccinated against COVID-19 While Pregnant or Breastfeeding: A Cross-Sectional Study in Italy.

The present study examined the role of the perception of risks and benefits for the mother and her babies in deciding about the COVID-19 vaccination. In this cross-sectional study, five hypotheses were tested using data from a convenience sample of Italian pregnant and/or breastfeeding women (N = 1104, July-September 2021). A logistic regression model estimated the influence of the predictors on the reported behavior, and a beta regression model was used to evaluate which factors influenced the willingness to become vaccinated among unvaccinated women. The COVID-19 vaccination overall risks/benefits tradeoff was highly predictive of both behavior and intention. Ceteris paribus, an increase in the perception of risks for the baby weighed more against vaccination than a similar increase in the perception of risks for the mother. Additionally, pregnant women resulted in being less likely (or willing) to be vaccinated in their status than breastfeeding women, but they were equally accepting of vaccination if they were not pregnant. COVID-19 risk perception predicted intention to become vaccinated, but not behavior. In conclusion, the overall risks/benefits tradeoff is key in predicting vaccination behavior and intention, but the concerns for the baby weigh more than those for the mother in the decision, shedding light on this previously neglected aspect.

Temporal dynamics of cognitive-emotional interplay in moral decision-making.

This study investigated the temporal dynamics of emotional and cognitive processing underlying decision-making in moral judgment. Thirty-seven participants were presented with a set of 60 dilemmas varying in whether killing one individual was an intended means to save others (instrumental dilemmas) or a foreseen but unintended consequence (incidental dilemmas). Participants were required to decide between Options A (letting a specific number of people die) and B (killing one person to save a specific number of people). ERPs were recorded to a slide displaying the letters A and B while subjects were deciding between the options, and movement-related potentials were recorded time-locked to the behavioral response, thus allowing the investigation of both stimulus- and response-related processes during decision-making. Ratings of emotional valence and arousal experienced during decision-making were collected after each decision. Compared with incidental dilemmas, instrumental dilemmas prompted a lower number of B choices and significantly more unpleasant decisions. A larger P260 component was found in the frontopolar and frontal areas when subjects were deciding on instrumental than incidental dilemmas, possibly reflecting an immediate affective reaction during the early stage of assessment and formation of preferences between available options. On the other hand, decisions on incidental dilemmas required greater attentional resources during the fairly controlled later processing, as reflected in the larger slow wave amplitudes. In addition, facilitation of action selection and implementation was found for incidental dilemmas during the second stage of decision-making, as supported by the larger amplitudes of both components of the Bereitschaftspotential.

Joint analysis of the intention to vaccinate and to use contact tracing app during the COVID-19 pandemic.

Pharmacological and non-pharmacological measures will overlap for a period after the onset of the pandemic, playing a strong role in virus containment. We explored which factors influence the likelihood to adopt two different preventive measures against the COVID-19 pandemic. An online snowball sampling (May-June 2020) collected a total of 448 questionnaires in Italy. A Bayesian bivariate Gaussian regression model jointly investigated the willingness to get vaccinated against COVID-19 and to download the national contact tracing app. A mixed-effects cumulative logistic model explored which factors affected the motivation to adopt one of the two preventive measures. Despite both COVID-19 vaccines and tracing apps being indispensable tools to contain the spread of SARS-CoV-2, our results suggest that adherence to the vaccine or to the national contact tracing app is not predicted by the same factors. Therefore, public communication on these measures needs to take in consideration not only the perceived risk associated with COVID-19, but also the trust people place in politics and science, their concerns and doubts about vaccinations, and their employment status. Further, the results suggest that the motivation to comply with these measurements was predominantly to protect others rather than self-protection.

Investigating the impact of offer frame manipulations on responders playing the ultimatum game.

The present study was designed to test the impact of frame manipulations on the decision-making of responders playing the ultimatum game. Experiment 1 investigated responders' event-related potentials (ERPs) measured in response to the offers as a function of the frame (i.e., negative: "the proposer keeps" versus positive: "the proposer offers"). While no difference in acceptation rate was found as a function of the offer's frame, electrophysiological results suggest that the stronger negative affective response to the offers in the negative frame (N400) was successfully reappraised by the responders (P600), possibly explaining why the offer frame manipulation did not modulate acceptation rates. No framing effect was found when the ultimatum game was played in its one-shot version (Experiment 2), suggesting that repeated measurements did not affect responders' behavior. However, an offer framing effect was found in female (but not in male) responders, when the complexity of the game statement increased, presumably recruiting more cognitive resources and taxing the reappraisal process (Experiment 3). Taken together, these results suggest that framing manipulations are associated with complex affective and cognitive processes, supporting the cognitive-affective tradeoff model.

People's perspectives about COVID-19 vaccination certificate: Findings from a representative Italian sample.

In Italy, like in other countries, issues still exist regarding how to reach high vaccine coverage and several countries have considered policies to increase vaccine uptake. In the present study, we focused on people who have a favorable attitude towards vaccination. In March-April 2021, we asked a representative sample of Italian participants (N = 1,530) to assess to what extent they would support the adoption of a COVID-19 vaccination certificate, excluding unvaccinated people from participating in public and cultural events. Furthermore, as the vaccination coverage increases, severe forms of COVID-19 requiring hospitalization more likely involve unvaccinated individuals, who might be perceived as those who don't contribute to ending the pandemic and who constitute a significant health cost for society. We then asked participants to assess to what extent they would favor the idea of requiring people who refuse the vaccine to pay for their own medical expenses in case of hospitalization. We hypothesized that support for the adoption of the vaccination certificate would be predicted by the COVID-19 vaccination status (received, booked, high-, medium-, low-willingness to be vaccinated, or refused) and by the same factors that are known to affect the willingness to get vaccinated. These factors were also tested in a model aimed at investigating if a vaccinated person would favor a measure requiring the unvaccinated individuals to pay for medical expenses. Results confirmed that the support towards the vaccination certificate policy was strongly predicted by the vaccination status and by factors known to affect the willingness to get vaccinated. Interestingly (and surprisingly), a similar pattern was observed for the support of the policy about medical expenses. In conclusion, support for a COVID-19 vaccination certificate was high among the Italian population in the early phases of the vaccination rollout. The findings are discussed considering potential policies to tackle the pandemic.

COVID-19 Vaccine Hesitancy in Italy: Predictors of Acceptance, Fence Sitting and Refusal of the COVID-19 Vaccination.

Background: The hesitancy in taking the COVID-19 vaccine is a global challenge. The need to identify predictors of COVID-19 vaccine reluctance is critical. Our objectives were to evaluate sociodemographic, psychological, and behavioral factors, as well as attitudes and beliefs that influence COVID-19 vaccination hesitancy in the general population of Italy. Methods: A total of 2,015 people were assessed in two waves (March, April and May, 2021). Participants were divided into three groups: (1) individuals who accepted the vaccination ("accepters"); (2) individuals who refused the vaccination ("rejecters"); and (3) individuals who were uncertain about their attitudes toward the vaccination ("fence sitters"). Group comparisons were performed using ANOVA, the Kruskal-Wallis test and chi-square tests. The strength of the association between the groups and the participants' characteristics was analyzed using a series of multinomial logistic regression models with bootstrap internal validation (one for each factor). Results: The "fence sitters" group, when compared to the others, included individuals of younger age, lower educational level, and worsening economic situation in the previous 3 months. After controlling for sociodemographic factors, the following features emerged as the main risk factors for being "fence sitters" (compared with vaccine "accepters"): reporting lower levels of protective behaviors, trust in institutions and informational sources, frequency of use of informational sources, agreement with restrictions and higher conspirative mentality. Higher levels of COVID-19 perceived risk, trust in institutions and informational sources, frequency of use of informational sources, agreement with restrictions and protective behaviors were associated with a higher likelihood of becoming "fence sitters" rather than vaccine "rejecters." Conclusions: The "fence sitters" profile revealed by this study is intriguing and should be the focus of public programmes aimed at improving adherence to the COVID-19 vaccination campaign.

Psychological well-being during the COVID-19 pandemic in Italy assessed in a four-waves survey.

COVID-19 pandemic had a negative impact on the mental health and well-being (WB) of citizens. This cross-sectional study included 4 waves of data collection aimed at identifying profiles of individuals with different levels of WB. The study included a representative stratified sample of 10,013 respondents in Italy. The WHO 5-item well-being scale (WHO-5) was used for the assessment of WB. Different supervised machine learning approaches (multinomial logistic regression, partial least-square discriminant analysis-PLS-DA-, classification tree-CT-) were applied to identify individual characteristics with different WB scores, first in waves 1-2 and, subsequently, in waves 3 and 4. Forty-one percent of participants reported "Good WB", 30% "Poor WB", and 28% "Depression". Findings carried out using multinomial logistic regression show that Resilience was the most important variable able for discriminating the WB across all waves. Through the PLS-DA, Increased Unhealthy Behaviours proved to be the more important feature in the first two waves, while Financial Situation gained most relevance in the last two. COVID-19 Perceived Risk was relevant, but less than the other variables, across all waves. Interestingly, using the CT we were able to establish a cut-off for Resilience (equal to 4.5) that discriminated good WB with a probability of 65% in wave 4. Concluding, we found that COVID-19 had negative implications for WB. Governments should support evidence-based strategies considering factors that influence WB (i.e., Resilience, Perceived Risk, Healthy Behaviours, and Financial Situation).