Will You Make Me Happy? The Role of Dating and Dating Violence Victimisation in Happiness Among Adolescents in Europe

Purpose: the aim of the article is to show the role of dating and dating violence victimisation, different socioeconomic characteristics, personal experiences of abuse, perceived social support, and the ability to resolve social problems in happiness among adolescents in Europe. Methods: the study had a cross-sectional design. The study participants were 1.528 students from secondary schools (age 13–16) in Spain, Italy, Romania, Portugal, Poland, and the UK. In order to understand which variables were associated with happiness, we fit multiple regression models. Results: the mean value of happiness is lower when teens are in a romantic or dating relationship and have suffered physical and/or sexual violence [β (CI 95%): -1.32(-2.41; -0.22)]. Both not being a victim of bullying and cyberbullying [β(CI 95%):0.90 (0.38; 1.41)] and not witnessing domestic violence against the mother β(CI 95%):1.97(1.06; 2.87)] is associated with relatively higher mean happiness value compared to having such experiences of violence. Also, problem-solving skills [β (CI 95%):0.13 (0.11; 0.14)] and perception of social support [β (CI 95%): 0.03 (0.02, 0.03)] is positively associated with mean value of happiness. Conclusions: there is an association between dating violence victimisation, and happiness among adolescents in Europe. The results suggest the importance of creating healthy, non-violent romantic relationships to build happiness during adolescence, the importance of seeking social support and to provide educational interventions focused on the development of problem-solving skills.

Romantic involvement and wellbeing are dynamically connected throughout one's lifetime, including during adolescence (Beckmeyer & Malacane, 2018;Braithwaite et al., 2010;Olson & Crosnoe, 2017;Proctor et al., 2009). Happiness can be defined as subjective wellbeing, which encompasses feelings of satisfaction, meaning, and purpose in life (Steptoe, 2019). According to the positive teen development model, which is the theoretical framework for this paper, young people's happiness and health can be developed through experiences that facilitate developmental outcomes (Benson et al., 2007).
Although positive emotions associated with happiness can be felt most of the time, these are not always experienced with high intensity (Diener, 2000). Experiencing a high sense of happiness enables us to cope better with everyday difficulties. According to the concept of adaptation, people react strongly to positive and negative life situations but then tend to adapt and return to their baseline level of happiness. An exception to this rule is when the situation is related to the central life goals that are defined as the most important. In this case, the situation may profoundly change the level of happiness (Diener, 2000;Fujita & Diener, 2005). The relationship between happiness and health is widely studied, with empirical evidence showing a positive correlation between the constructs (Pierewan & Tampubolon, 2015). Happiness seems to be a protective factor that helps to maintain physical and mental wellbeing and reinforces an individual's adjustment to stressful events (Diener & Chan, 2011). Happier youths and adults maintain more satisfying relationships than those who are less happy (Park, 2004).
More research explores the meaning of intimate relations in building happiness in adult life than during the teenage period. In emerging adulthood, there is a positive connection between intimate relationships and happiness (Demir, 2008). Research shows that college students in committed romantic relationships experience greater wellbeing than single college students (Braithwaite et al., 2010). Furthermore, those in intimate relationships in adulthood enjoy higher levels of wellbeing than adults who are not in such relationships (Simon, 2002;Williams 2003).
Although, in recent decades, we have observed increasing interest in the issues of romantic relationships among young people, they still have not received as much attention as adult relationships (Furman, 2006(Furman, , 2018. As emphasised in the literature, this may be related to myths about such relationships in adolescence, which presented them as insignificant, superficial, and transitory, associating them mainly with negative behaviours (Collins, 2003).
As the positive teen development model suggests, healthy relationships with peers are one of the most important developmental resources (Benson et al., 2007). Intimate teen relationships play a fundamental role in individual development and key development tasks, such as identity, family relationships, close relationships with peers, sexuality, school achievement, and career planning (Furman & Shaffer, 2003). However, according to Joyner and Udry, teens who formed romantic relationships experienced more symptoms of depression than teens who were not involved in such relationships (Joyner & Udry, 2000). This suggests that romantic relationships in adolescence are associated with depression rather than happiness, but research results underline essential factors that shape such links. For example, it has been shown that breaking up -rather than being in a romantic relationship -can explain elevated symptoms of depression. A 'breakup' is the most common trigger for the first episode of major depression among adolescents (Monroe et al., 1999;Starr et al., 2012). Furthermore, intimate youth relationships are also associated with rapidly changing and extreme feelings, such as love and jealousy (Giordano et al., 2006). Strong feelings in intimate relationships undoubtedly apply to the sexual potential in the context of dating and romantic relationships. Additionally, teenagers experience awkwardness in the presence of a partner (Giordano et al., 2006).
It seems that the wellbeing of adolescents' intimate relationships depends on individual life goals and the quality of the relationship. As positive interactions with romantic partners are expected to increase wellbeing, negative interactions are expected to undermine it . Hence, when adolescents are involved in intimate relationships that do not meet their expectations or cause distress, more significant depressive symptoms are reported when compared to those with little or no romantic involvement .
According to research, one of the important threats to a youth's wellbeing and health is experiencing violence in an intimate relationship (Peterman et al., 2015). Dating violence is defined as physical, psychological, sexual, and/or social aggression within intimate relationships, including stalking (Brooks-Russell et al., 2015;Vives-Cases et al., 2021). It may occur both in direct and online interactions, between current or former partners and in same-or different-sex relationships. Physical violence includes beating, pushing, strangling, shaking, jerking, hitting, or using a weapon. Emotional violence involves behaviours that cause emotional damage, trauma, or fear (e.g., threatening someone with physical violence, discrediting and intimidating the victim, damaging the victim's possessions). Sexual violence includes forcing someone to engage in a sexual act against their will (regardless of whether the sexual act occurs) or engaging in sexual activities with a person who cannot express their consent. Social violence comprises any abusive action with social impacts, like isolating the victim from their family and friends and controlling the victim's behaviour. Finally, stalking relates to harassment that causes the victim to feel fear (Beatriz et al., 2018;Brooks-Russell et al., 2015).
There are many dating violence risk factors, both individual (e.g., aggressive behaviour), family (e.g., violence between parents), peer (e.g., models of intimate violence among peers), and sociocultural (Brooks-Russell et al., 2015;Jankowiak et al., 2020;Pérez-Martínez et al., 2020). Among the last group, gender norms are essential, for instance overtly hostile judgments and stereotypes about women or the belief that they need protection (ambivalent sexism), which shape social beliefs about gender inequality (Glick & Fiske, 1996). Research on adolescents' sexual and reproductive health has identified stereotypes and gender inequality as key risk factors for engaging in dangerous and violent behaviour in an intimate relationship. Girls pay an exceptionally high price because traditional upbringing and cultural norms deprive them of their competencies and the possibility of negotiating safe sex and refusing of unwanted sex (Tolman et al., 2003).
The consequences of dating violence are both short and long-term and affect many areas of youth functioning, like physical and psychological health and academic performance (Beatriz et al., 2018;Jankowiak et al., 2021;Peterman et al., 2015;Wilson & Maloney, 2019). Victims of dating violence may exhibit depression, anxiety, suicidal thoughts, psychoactive substance use disorders, auto-aggression, eating disorders, and injuries requiring medical care (e.g., from partner aggression and self-aggression) (Beatriz, 2018;Wilson & Maloney 2019). This kind of violence can also be a precursor of intimate partner violence throughout adult relationships later in life (Shook et al., 2000), especially when there is a strong association between perpetrating violence and holding conservative gender beliefs (Neves et al., 2016).
According to the positive teen development model, the experience of violence is a risk factor that jeopardizes youth development (Benson et al., 2007). There is also a connection between different types of family and peer violence and a sense of wellbeing (Finkelstein & Yates, 2001), but also between the experience of domestic and peer violence and dating violence. For example, witnessing domestic violence can increase the acceptance of violence as an appropriate measure to resolve conflicts in a relationship and increase the risk of the dating violence acceptance (Simons et al., 2012). There are also links between physical aggression toward peers and dating and sexual aggression (Reyes & Foshee, 2013). Some studies suggest a significant negative relationship between children's subjective wellbeing and bullying (Savahl et al., 2019).
Since teenagers declare that intimate relationships are extremely important for them (Karney et al., 2007), creating these relationships is, therefore, one of the essential developmental goals of adolescence so they can be a source of happiness for young people. The exception is the relationship that involves violent experiences. We recognised that dating violence would be a factor in reducing happiness. Moreover, it was assumed that selected individual and social factors could increase or decrease the feeling of happiness and explain the relationship between dating, dating violence, and happiness.
The positive teen development model assumes a dynamic and mutually reinforcing relationship between various individuals (e.g., social skills, solving problems) and contextual factors (e.g. both protective and risk factors experienced in multiple ecological contexts: romantic relationships, peer, family, school, community) (Benson et al., 2007). According to this model, youth are perceived as capable of acting and changing the contexts in which they live and as having resources (e.g., social skills), that should be developed to support positive development. At the same time, the context (e.g., supportive relationships, engaged adults, poverty, family violence, bullying) affects development. Contexts can be intentionally altered to enhance the developmental success, and changes in these contexts change the person (Benson et al., 2007). These assumptions were the basis of the project Lights4Violence, which allowed us to explore how socioeconomic characteristics, personal experiences, resources, personal and environmental, and competencies are associated with teenagers' experiences of happiness.
The project Lights4Violence was a longitudinal quasi-experimental educational study aimed at adolescents between 13 and 16 and focused on promoting adolescents' capabilities to improve their intimate relationships with their peers (Vives-Cases et al., 2019). Research results presented in this study concern only the pre-intervention input data. This study aimed to explore the mean value of happiness in adolescents with different sociodemographic characteristics (students' age, sex, and parents' employment); dating and non-dating; with personal experiences of violence (dating violence, bullying/cyberbullying, physical and sexual abuse in childhood); with a different perception of social support and social problemsolving skills.

Design
The study had a cross-sectional design. Data were gathered from adolescents at the baseline stage of their engagement in the Lights4Violence project (Vives-Cases et al., 2019). The data were collected using an online questionnaire including demographic and socioeconomic variables, the experience of violence and dating, the Student Social Support Scale, the Social Problem-Solving Inventory-Revised Scale, the Subjective Happiness Scale and other scales defined by the project Lights4Violence.
The data were gathered in 12 schools between October 2018 and February 2019. The programme content was presented, and the opportunity to participate was offered to the school headteachers. Participation was offered to all the students of the classes selected. The percentage of participation was 98.78%.

Ethical considerations
Data were collected by project partners based at universities in various countries, and all the information gathered by the project partners and beneficiaries was confidential. Participation was voluntary. Each partner was required to obtain the permission of their own ethics committees along with a signed informed consent document from the school, headteachers, parents, and students. Participants created a unique participant code for themselves at the first data collection point. In cases in which a student reported being abused by an adult, each country used its own protocol to inform the school. Due to the anonymity of participants responding to the questionnaire, it was impossible to identify the victims. However, it was possible to notify the school about the number of student reports of abuse. Each school was responsible for following the respective protocol to intervene.
The Lights4Violence project protocol was approved by the ethical committee of the University of Alicante, the University Institute of Maia, Universitatea de Medicina si Farmacie Grigore T. Popa, and Adam Mickiewicz University. Waivers were obtained from the Libera Universita Maria SS. Assunta of Rome and Cardiff Metropolitan University. These ethics approvals covered the individual schools where the intervention was performed. It was also registered in ClinicalTrials.gov by the coordinator (Clinicaltrials.gov: NCT03411564. Unique Protocol ID: 776,905. Date registered: 18 January 2018).

Participants
We recruited a non-probabilistic sample of 1.555 participants aged between 13 and 16 from secondary schools in Alicante, Spain (130 girls and 125 boys), Rome, Italy (206 girls and 79 boys), Iasi, Romania (214 girls and 129 boys), Matosinhos, Portugal (125 girls and 134 boys), Poznan, Poland (135 girls and 55 boys) and Cardiff in the UK (112 girls and 92 boys). The analyses in this text concern the 1,528 students who filled in the Subjective Happiness Scale. Once we eliminated missing values, the regression models included 1509 cases.
A statistical power analysis was performed for sample size estimation based on data from previously published random-effects meta-analysis of 23 studies about school-based interventions at preventing violence and negative attitudes in teen dating relationships (De La Rue et al., 2017). Hence, given the 1528 participants recruited at baseline of Lights4Violence project (Vives-Cases et al., 2019), and assuming a signification level of 0,05 and a power of 80%, this study can detect mean differences more significant than 0.75 units.

Dependent variables
In this study, the predicted variable was subjective happiness, measured by the Subjective Happiness Scale.
The Subjective Happiness Scale is a global measure of subjective happiness that evaluates wellbeing as a global psychological phenomenon. In our study, the Subjective Happiness Scale showed satisfactory internal consistency and Cronbach's alpha was 0.701. The Subjective Happiness Scale contains four items (Likert-type responses with seven options) for instance 'In general, I consider myself: Not a very happy person … A very happy person'; 'Compared to most of my peers, I consider myself: Less happy … More happy' (Lyubomirsky & Lepper, 1999).

Independent variables
In this study, we considered a predictor variable related to experiences of a dating relationship. The respondents were asked: Have you ever been in a dating relationship? Those who had been in a dating relationship were asked: 'Has anyone that you have ever been on a date with physically hurt you in any way? (For example, slapped you, kicked you, pushed, grabbed, or shoved you)'; 'Has the person that you have been on a date with ever attempted to force you to take part in any form of sexual activity when you did not want it?'; 'Has the person that you have been on a date with ever tried to control your daily activities, for example, who you could talk with, where you could go, how to dress, check your mobile phone, etc.?'; 'Has the person that you have been on a date with ever threatened you or made you feel threatened in any way?'.
Exposure to dating experiences, was measured by a variable created for the data analysis with the following categories: has never been in a partner relationship; has been in a relationship but never experienced violence; has been in a relationship and has experienced control and/or fear dating violence; has been in a relationship and has experienced physical and/or sexual dating violence.

Covariates
The following covariates were also used for this study: • Sociodemographic characteristics: students' age, sex, and parents' employment. The answers were collected through a multiple-choice format. The employment variable was classified as 'paid work' and 'unpaid work' (homemaker, unemployed, retired, and unable to work because of a disability, student, deceased).
• Experiences of abuse and/or violence by an adult in childhood before the age of 15. Three questions with dichotomous answers (yes/no) were included: 'Before you were 15 years old, did any adult -that is, someone 18 years or older -physically hurt you in any way? (For example, slapped you, kicked you, pushed, grabbed, or shoved you)'; 'Before you were 15 years old, did someone 18 years or older force you to participate in any form of sexual activity when you did not want to?'; 'Before you were 15 years old, did you witness in your family environment someone (your father or your mother's partner) physically beat or mistreat your mother?'. • Bullying and cyberbullying scales were adapted from the Lodz Electronic Aggression Questionnaire (LEAQ). The tool measures bullying and cyberbullying, defined as a serious form of peer violence that is regular, intentional, and involves an imbalance of power that includes the involvement of a perpetrator and a victim, also in the context of current or former romantic partners. The four questions refer to the last three months, and the scale includes Likert answers (never-3 times or more) (Pyżalski, 2012). For its analysis, the variable was categorized into two categories (victim of bullying and-or cyberbullying/ no victim of bullying and-or cyberbullying). • The Child and Adolescent Social Support Scale is a 60-item, multidimensional scale that measures the social support perceived by students from parents, teachers, classmates, friends, and 'other people at school' (e.g., a principal or counsellor), and ranges between 12 and 72 for each area. It includes subscales of 12 items each with 6-point Likert-type response categories that range from never to always. A higher score indicates greater social support. Students rate each behaviour on two dimensions: availability (a 6-point rating scale) and frequency (a 3-point rating scale) (Malecki & Demary, 2002). For this study, we only analysed the results of the frequency dimension because the trend of both dimensions related to dependent variables and co-variables was very similar. In our study, The Child and Adolescent Social Support Scale showed satisfactory internal consistency (Cronbach's alpha) ranged 0.96. • The Social Problem-Solving Inventory-Revised Scale abbreviated version is a brief scale of 25 items that indicates the ability to resolve social problems. Items are answered on a 5-point Likert-type scale, from 'this is not true' to 'extremely true'. Items are distributed in five sub-scales (five items in each subscale) that evaluate functional and dysfunctional aspects of the ability to problem solve. The functional dimension is evaluated through two subscales: Positive Problem Orientation and Rational Problem Resolution; while the dysfunctional dimension is evaluated through the subscales Negative Problem Orientation, Avoidance Style, and Impulsivity/Carelessness Style. These five dimensions enable the obtainment of a total score that corresponds to a general estimation of the ability to solve problems, in addition to the average scores in each dimension (D'Zurilla et al., 1998). Only the summary result was used in this work. In our study The Social Problem-Solving Inventory-Revised Scale showed satisfactory internal consistency (Cronbach's alpha) ranged 0.84.
Categorical variables were included in the analysis as dummy variables and the scales "Social Problem-Solving Inventory-Revised Scale", and the "Child and Adolescent Social Support Scale" were analysed as continuous variables.
All the models were adjusted by country (Poland, Portugal, Spain, Italy, Romania, and the United Kingdom). This means that we include the variable "country" in the regression models, and therefore the results we obtain are independent of the country where the information was collected. This is done to eliminate the possible variability that could exist between countries, both culturally and in the collection of information. In this way, the association measures obtained are independent of the country. The research tools were translated by reverse translation technique in all participating countries.

Statistical Analyses
A description of the total sample and of the sample stratified by sex, was carried out for each of the variables included in the study. Mean value of happiness and standards deviations was calculated for each of the categorical covariates included.
To understand which variables were associated with happiness, we fit multiple regression. For the estimation of the models, robust standard errors were calculated, because heteroscedasticity was detected using the White's test (p = 0.0012). Multicollinearity and normality of the variables were evaluated using a Q-Q plot. No violations of these assumptions were observed in any model.
Statistical significance was considered to be a p-value of < 0.05. IBM SPSS Statistic 27 and Stata 16.1 were used.

Description of the Sample
The mean value for happiness is 18.81 (min. 4, max. 28, SD = 5.28), 18.52 for girls and 19.43 for boys. Table 1 shows descriptive data. It is shown the variables distribution, the mean happiness value and the SD for the whole sample and for the sample stratified by sex.
The average age of the sample was 14.3 years (SD = 1.5). Most of the participants' parents were in paid employment.
About 20.5% of the girls and 18.7% of the boys indicated that they had suffered dating violence in their current or previous relationships. A lower mean happiness level was present in relations where dating violence experience took place, in particular physical dating violence (Mean:16.53 SD: 5.77), sexual dating violence (Mean:15.55; SD:5.86) or fear from partner (Mean:15.53; SD:5.71) than among those who were never dating (Mean:18.91 SD:18.91).
About 37.5% of students reported that they had been exposed to bullying and/or cyberbullying. Victims of bullying and cyberbullying reported lower mean values of happiness (Mean17.22; SD: 5.37) than among those who were never victims of bullying and cyberbullying (Mean:19.76; SD:4.99).
Witnessing violence was experienced by 10.7% of the girls and 8.5% of the boys. People who have been witnessed family violence against the mother have a lower mean happiness value (Mean:15.40; SD:5.47) than those who have not witnessed family violence against the mother (Mean:19.18; SD:5.12). The Spearman correlation between Social Support Scale and Happiness scale was 0.392. The Spearman correlation between Social Problem Solving Scale and Happiness scale was 0.416. Table 2 shows linear regression results. Tables 3, 4 and 5 show the multiple regression results. In Table 3 Model 1 is adjusted by sociodemographic variables. In Table 4 Model 2 is adjusted by same variables as Model 1 and experience of violence. In Table 5 Model 3 is adjusted by Model 2 variables and problem solving and social support scales. All models are also adjusted by country.

Dating, dating violence victimisation, and teen happiness
Taking as a reference those who have been in a no violence dating relationship, the mean value of happiness was lower when teens suffered physical and/or sexual violence [β (CI 95%):-3,34 (-4.35; -2.33) or had experienced another dating violence (control and/or fear) [β (CI 95%): -1,14(-2.09; -0.19)]. At the same time, no significant differences were found between those teens who are in non-violent relationships and those who have never been dating. (Table 2).
The mean value of happiness was higher when teens were not experienced bullying or cyberbullying [β (CI 95%): 2.54(2.00; 3.08)], when they have no had witnessed abuse and/ or violence against their mother. Social Problem-Solving Inventory-Revised Scale and The Child and Adolescent Social Support Scale were positive correlated with happiness (Table 2).
In the final model it is confirmed that using as a reference those who have never been in a violent dating relationship, the mean value of happiness is lower when teens suffered physical and/or sexual violence [β (CI 95%): -1.32(-2.41; -0.22)] (   The standardized beta values show us that these two scales, Social Problem Solving Inventory-Revised Scale and the Child and Adolescent Social Support Scale, are the ones with the greatest relative importance in our model.

Discussion
We examined the associations of dating and dating violence with happiness. Results show that the mean value of happiness was lower when teens suffered physical and/or sexual violence in their intimate relationships. At the same time, no significant differences were found between teens in non-violent relationships and those who have never been dating.
The results of previous studies indicate that life circumstances do not significantly correlate with happiness levels (Fujita & Diener, 2005), although the level of happiness may change if the factors influencing it are connected to the life goals perceived as most important. According to the positive youth development theory, adolescents select from a range of developmental opportunities a subset that has psychological and social advantages for prioritised personal goals (Benson et al., 2007;Karney et al., 2007), and as previous research has shown, adolescents report that intimate relationships are critically important to them  (Karney et al., 2007). If teens pursuing these personal goals experience violence from a partner, their happiness is at risk. On the other hand, those teens who are in non-violent relationships do not differ in their level of happiness from those who have never had an intimate relationship and have never been dating. Thus, non-dating adolescents are not pursuing goals that are important to most of their peers and their happiness is not significantly different from those who are dating. As previous studies have shown, dating is often associated with difficult emotions (Giordano et al., 2006). It can be assumed that coping with these emotions and also taking on new roles such as being a partner in an intimate relationship is a big challenge for young people. Thus, despite the satisfaction of being in an intimate relationship, facing new challenges results in differences in happiness among dating teens that are no higher than those who do not date. Our study participants mainly were young adolescents. Perhaps the importance of dating for happiness will change with adolescents' age. Further research is needed to deepen this research thread.
In the model, we also included other predictors that may explain the level of happiness. However, social support and problem-solving skills are associated with happiness regardless of the dating experience. This is in line with the model of the L4V positive youth devel- opment programme's fusion of an active, engaged, and competent person with receptive, supportive, and nurturing ecologies (Benson et al., 2007). These results support utilisation of prevention projects focussed on developing the ability to seek social support and the development of problem-solving skills. These social competencies can be crucial to maintaining happiness when adolescents experience violence from a dating partner. Unfortunately, perceived support and problem-solving skills are not sufficient to maintain happiness for those who have witnessed domestic violence against their mother or are victims of bullying (although the influence of these factors is slightly smaller in Model 3 than in Model 2). As our research shows, not being a victim of bullying and cyberbullying and not witnessing domestic violence against the mother was associated with a higher mean value of happiness. Our results support findings from other studies. For example, witnessing domestic violence lowers the wellbeing of children and adolescents and causes emotional trauma (Feerick & Haugaard, 1999;Finkelstein & Yates, 2001;Lambert et al., 2014;Lepistö et al., 2011). Also, the link between bullying, and wellbeing is well documented (Jankauskiene et al., 2008;Navarro et al., 2015). Being a victim of bullying increased frequency of mood disorders, psychosomatic disorders, self-harm, school avoidance and suicidal ideations (Dresler-Hawke & Whitehead, 2009;Moore et al., 2017). Although previous studies have shown that social support (Hefner & Eisenberg, 2009;Jankauskiene et al., 2008) and social competences (Spence et al., 2002) are of great importance for adolescents' mental health and subjective wellbeing, our research shows that experiences related to domestic violence and bullying/cyberbullying may be so strong that even the including problem-solving skills and seeking social support variables in the model only slightly explains relationship between this kind of experiences and happiness.
Our study indicated that happiness is lower among older teens and girls. Similar results on the importance of age were also obtained in other studies of the happiness level of early adolescence (Uusitalo-Malmivaara, 2014;González-Carrasco et al., 2017). Many of the teens in our project were in early adolescence. This stage is characterised by rapid physical changes, significant cognitive maturation, and increased sensitivity to peer approval (Newman & Newman, 1987). During early adolescence, teens experience many changes within a short period, which may lead to anxiety and confusion. The body changes and awakening sexuality becomes a source of intense tension and fear. According to the research, early to middle adolescence marks a point of increased depressed mood and depressive syndromes (Compas et al., 1995). Emotional stabilisation takes place after the age of 16 because the strength and variability of emotions experienced decreases, and the level and manner of expression of emotions are controlled and regulated to a greater extent by the adolescent. In our study, adolescents from the age group over 15 are likely to have already experienced all the rapid developmental changes characteristic of early adolescence but have not yet acquired the ability to control emotions and accept the changes that have occurred, because developmentally this usually takes place between the ages of 16 and 19. Our research shows that boys have a higher level of happiness than girls. Other studies have also shown lower wellbeing for girls during adolescence (González-Carrasco et al., 2017). This may indicate that girls are more sensitive to the changes experienced during this life phase. Our research shows that experiencing social support and the ability to solve social problems can ease the negative effects associated with age but not gender. Therefore, it can be assumed that developing the ability to seek social support and solve problems may be important for main-taining happiness during the rapid changes in early adolescence. However, ways to support girls' well-being should be explored.
In interpreting our results, it is necessary to consider some limitations. The study has a cross-sectional design, and all causal relationships are drawn from the theory and should be confirmed in longitudinal studies. The sampling procedure does not allow us to generalise the study results to the population of each country. It was calculated to have enough statistical power to analyse the results as a whole. The perception of having been exposed to dating violence could be different depending on the students' cultural context. To address this, our models have been adjusted by country, but there may be residual confusion.

Conclusion
There is an association between dating violence victimisation and happiness among adolescents in Europe. Despite the limitations, we can say that happiness is lower when teens are in a romantic or dating relationship and suffer physical and/or sexual violence. In addition, social support and problem-solving skills are associated with happiness irrespective of the dating experience. Prevention programmes aimed at increasing social support seeking skills and developing problem-solving skills can help teens stay happy in situations where they experience violence from a dating partner. Problem-solving skills and awareness of social support are essential for building happiness in adolescence. Unfortunately, experiences such as witnessing violence against the mother and being the victim of bullying/cyberbullying reduce the chances of happiness in adolescence.
Ethics approval Data was collected by project partners based at universities in various countries and all the information gathered by the project partners and beneficiaries was confidential. Participation was voluntary. Each partner was required to obtain the permission of their own ethics committees along with a signed informed consent document from the school, headteachers, parents, and students. Participants created a unique participant code for themselves at the first data collection point. In cases in which a student reported having been abused by an adult, each country used its own protocol to inform the school. Due to the anonymity of participants responding to the questionnaire, it was impossible to identify the victims. However, it was possible to inform the school about the number of student reports of abuse. Each school was responsible for following the respective protocol to intervene. The Lights4Violence project protocol was approved by the ethical committee of the University of Alicante, the University Institute of Maia, Universitatea de Medicina si Farmacie Grigore T. Popa, and Adam Mickiewicz University. Waivers were obtained from the Libera Universita Maria SS. Assunta of Rome and Cardiff Metropolitan University. These ethics approvals covered the individual schools where the intervention was performed. It was also registered in ClinicalTrials.gov by the coordinator (Clinicaltrials.gov: NCT03411564. Unique Protocol ID: 776,905. Date registered: 18 January 2018).
Consent to participate; Consent for publication All authors whose names appear on the submission: 1) made substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data; or the creation of new software used in the work; 2) drafted the work or revised it critically for important intellectual content; 3) approved the version to be published; and 4) agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Implications and Contribution
The final findings highlight the importance of creating healthy, non-violent romantic relationships for building happiness in adolescence as well as the need to develop educational interventions focused on the development of problem-solving skills and seeking social support.
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