The Prospective Association Between Empathy and Defending Behavior: Moderation by Peer Likeability The Faculty of Social Sciences Department of Psychology Master's thesis Author: Siiri Rantanen Supervisors: Sarah Malamut, University Research Fellow Eerika Johander, Postdoctoral Researcher 10.6.2025 Turku The originality of this thesis has been checked in accordance with the University of Turku quality as- surance system using the Turnitin OriginalityCheck service. Master's Thesis Subject: Psychology Author: Siiri Rantanen Title: The Prospective Association Between Empathy and Defending Behavior: Moderation by Peer Likeability Supervisors: University Research Fellow Sarah Malamut, Postdoctoral Researcher Eerika Johander Number of pages: 32 pages Date: 10.6.2025 Abstract Defending victimized peers in schools is shaped by a complex interplay of intrapersonal and interper- sonal factors. However, previous research has primarily focused on concurrent associations of defend- ing, with only limited longitudinal research examining which factors can lead to more defending over time. To fill this gap, the current study examines the longitudinal association between empathy and defending behavior, as well as whether this association is moderated by peer likeability. The data was collected as part of the CHALLENGE project within INVEST Psychology at the Univer- sity of Turku. Data collection occurred in Finnish schools in seven waves over the course of three aca- demic years. For the current study, we utilized data from Wave 1 (T1) and Wave 3 (T2), which took place in the fall and spring semesters of the academic year, respectively. The sample comprised of 3662 participants in 4th to 9th grade (Mage = 13.05 years, SD = 1.68). Participants completed a self-re- port questionnaire on empathy and assessed their peers’ defending behaviors and likeability with a peer nomination method. Gender, grade level, and prior defending behavior were included as control variables. The data was analyzed with multilevel linear regression analysis with moderation. The results revealed a significant positive association between empathy (T1) and defending behavior (T2) over time. How- ever, this association was specifically found for well-liked individuals and not for participants that were less liked among their peers. Previous defending behavior (T1) was also found to be a significant predictor of later defending. This study broadens the understanding of how peer likeability impacts the association between empa- thy and defending behavior at school. These findings suggest that the prospective empathy-defending association is dependent on youth’s social relationships, as they may be better positioned to support victimized peers due to their more stable social standing. Key words: empathy, defending, peer likeability Pro gradu -tutkielma Oppiaine: Psykologia Tekijä: Siiri Rantanen Otsikko: Empatian pitkittäinen yhteys puolustuskäyttäytymiseen: vertaisten kesken pidettävyyden rooli Ohjaajat: Yliopistotutkija Sarah Malamut, Tutkijatohtori Eerika Johander Sivumäärä: 32 sivua Päivämäärä: 10.6.2025 Tiivistelmä Kouluissa esiintyvä puolustuskäyttäytyminen kiusaamistilanteissa rakentuu monimutkaisesta sisäisten ja sosiaalisten tekijöiden vuorovaikutuksesta. Pitkittäistutkimusta aiheesta on kuitenkin toistaiseksi vain vähän. Tässä tutkimuksessa tarkasteltiin empatian ja puolustuskäyttätymisen välistä pitkittäistä yhteyttä sekä sitä, vaikuttaako oppilaan pidettävyys vertaisten keskuudessa empatian ja puolustuskäyttäytymisen väliseen yhteyteen. Tutkimuksen aineisto on kerätty osana Turun yliopiston INVEST Psykologian tutkimusryhmän CHALLENGE-hanketta. Aineistonkeruu toteutettiin suomalaisissa peruskouluissa seitsemässä aikapisteessä kolmen lukuvuoden aikana. Tässä tutkimuksessa hyödynnettiin ensimmäisen (T1) ja kolmannen (T2) aikapisteen aineistoa, jotka ajoittuivat lukuvuoden syksyyn ja kevääseen. Aineisto koostui 4.–9.-luokkalaisista (n = 3662; Mikä = 13.05 vuotta, SD = 1.68). Osallistujat vastasivat koulussa empatian itsearviointikyselyyn sekä arvioivat vertaistensa puolustuskäyttäytymistä ja pidettävyyttä toveriarviointimenetelmällä. Kontrollimuuttujina huomioitiin sukupuoli, luokka-aste ja aiempi puolustuskäyttäytyminen. Aineiston analysoimiseen käytettiin monitasoista lineaarista regressioanalyysiä. Tulosten mukaan empatia (T1) oli positiivisesti yhteydessä myöhempään puolustuskäyttäytymiseen (T2), ja tämä yhteys oli erityisen vahva vertaisten keskuudessa pidetyillä oppilailla. Lisäksi aiempi puolustuskäyttäytyminen (T1) ennusti merkitsevästi myöhempää puolustamiskäyttäytymistä. Tämä tutkimus laajentaa ymmärrystä siitä, miten pidettävyys vertaisten kesken vaikuttaa empatian ja puolustuskäyttäytymisen väliseen yhteyteen kouluympäristössä. Tulokset viittaavat siihen, että pidetyillä oppilailla saattaa olla paremmat edellytykset auttaa kiusattuja tovereita vakaamman sosiaalisen asemansa ansiosta. Avainsanat: empatia, puolustaminen, pidettävyys vertaisten kesken Table of Contents 1 Introduction 6 1.1 Defending 6 1.2 The Association Between Empathy and Defending Behavior 8 1.3 The Moderating Role of Peer Likeability 9 2 Aims and Hypothesis 11 3 Method 12 3.1 Participants 12 3.2 Research Ethics 12 3.3 Procedure 13 3.3.1 Data Collection 13 3.4 Measures 13 3.4.1 Outcome Variable 13 3.4.2 Main Predictor 14 3.4.3 Moderator 14 3.4.4 Control Variables 14 4 Analytic Plan 16 4.1 Data Preparation 16 4.2 Handling of Missing Values 16 4.3 Main Analyses 17 5 Results 18 5.1 Descriptive Statistics and Preliminary Analyses 18 5.2 Main Analyses 19 6 Discussion 21 6.1 Prospective Associations Between Empathy and Defending 21 6.2 The Moderating Role of Peer Likeability 21 6.3 Strengths, Limitations, and Future Directions 23 6.3.1 Strengths 23 6.3.2 Limitations and Future Directions 23 7 Conclusions 25 References 26 Appendices 36 Appendix 1: Table 2 Multilevel Linear Regression Models 36 6 1 Introduction Bullying is a common phenomenon and significant global health problem with long-lasting consequences (McDougall & Vaillancourt, 2015). Bullying is exposing an individual repeat- edly, and over time to negative actions by one or more peers (e.g., Olweus, 1993). These neg- ative actions are taken intentionally to inflict, injury, or to cause discomfort to the victimized individuals. Bullying can take the form of physical or verbal abuse aimed at harming the vic- tim (American Psychological Association, 2018). However, it is distinct from other forms of harassment and interpersonal violence due to its characteristic power imbalance (Olweus, 1993), which often leaves victimized youth in a vulnerable position, making it challenging to get themselves out of the situation or defend themselves. The consequences of bullying are far-reaching. Being victimized in childhood or adolescence is associated with an elevated risk of developing internalizing problems later in life (Reijntjes et al., 2010), such as anxiety, depression, and self-harm (Lereya et al., 2015). Additionally, victimization has been linked to other psychiatric outcomes, including antisocial personality disorder, substance abuse, and suicidality (Copeland et al., 2013). These findings highlight the various negative long-term consequences of being victimized. Given the far-reaching impact of bullying, identifying effective strategies to intervene and prevent it is essential. Defending victimized youth has been shown effective in reducing bul- lying (Nocentini et al., 2013). Moreover, higher levels of defending in classrooms might even protect at-risk children becoming victimized (Kärnä et al., 2010). Defended individuals also experience better social and mental health outcomes (Sainio et al., 2011). Due to these poten- tial benefits of defending, it is important to understand the factors that positively predict de- fending behavior. In particular, this study focuses on the prospective association between em- pathy and defending behavior, considering peer status (specifically peer likeability) as a po- tential moderator. By enhancing understanding in this area, the findings may contribute to bet- ter understanding of the circumstances under which youth might defend their peers. 1.1 Defending Defending has been defined as prosocial behavior aimed at supporting individuals who are be- ing victimized (Salmivalli, 2010). Defending can assist victimized youth in various ways (Lambe & Craig, 2020). Commonly, defending behavior is categorized into direct and indirect 7 defending (Ma et al., 2019; Trach et al., 2010). Direct defending often involves assertive, so- lution-oriented actions, such as confronting the bully, while indirect defending includes be- haviors that provide emotional support or seek intervention from authorities or other people (Lambe & Craig, 2020). Both types of defending share the goal of intervening in and mitigat- ing bullying situations, but they focus on different aspects: direct defending targets the bully, while indirect defending prioritizes the well-being of the victimized and aids their recovery. Defending behavior is often assessed with peer nominations, since they have been shown to be stable and reliable (Gest et al., 2006). It can also be assessed through self-reports, of which there is only limited research on how they relate to peer reports (Salley et al., 2015). With peer nominations, students have previously been assigned different participant roles in bully- ing situations (Salmivalli et al., 1996), however, these roles are dynamic based on peer con- text and situational variables (Huitsing et al., 2014). Additionally, students may engage in be- haviors that correspond to multiple roles (Demaray et al., 2021). Thus, in this study we avoid categorizing individuals and view defending behavior as a continuous variable, which also aligns with the approach in recent literature. Consistent with theoretical models of Prosocial Risk Taking (Do et al., 2017), helping others may come with personal costs or social risks, especially in peer contexts like bullying. Recent evidence suggests that defending does not actually position defenders at risk of victimization (Malamut et al., 2023) or internalizing symptoms (Malamut et al., 2021). Instead, engaging in defending may even be rewarded with increased popularity within the peer group (van der Ploeg et al., 2017). Despite this, some students might be hesitant to defend out of fear of be- coming victimized themselves by risking their social standing within the peer group (Strind- berg et al., 2020). Indeed, defending appears to be relatively rare (Ma et al., 2019; Pepler & Craig, 1995). Thus, investigating factors that promote defending over time is important, as de- fending can indeed be an effective strategy for reducing bullying (Nocentini et al., 2013), and defenders appear to be important in reducing peer victimization (Meter & Card, 2015). Addi- tionally, defended individuals experience reduced frequencies of victimization accompanied with better adjustment, less anxiety, and less rejection than their undefended peers (Sainio et al., 2011). Given the importance of defending in decreasing bullying, we are interested in fac- tors that might predict defending behavior longitudinally. 8 1.2 The Association Between Empathy and Defending Behavior Intrapersonal factors have been found to be associated with defending behavior, with empathy being a key correlate (Ma et al., 2019; Peets et al., 2015). Empathy has been defined as under- standing another person from their perspective (e.g., American Psychological Association, 2023). It is an emotional and cognitive response to the experiences of others (Cuff et al., 2016; Eisenberg et al., 2015; Trach et al., 2023). The emotional component involves sharing and feeling another person’s perceived emotions (Eisenberg & Strayer, 1990), which are often identical or congruent with the other person’s emotional state (Albiero et al., 2009); this is re- ferred to as affective empathy. The cognitive component involves recognizing and under- standing another person’s state of mind (Dvash & Shamay-Tsoory, 2014; Dymond, 1950), and is known as cognitive empathy. A robust body of research demonstrates a positive concurrent association between empathy and defending behavior observed across diverse age groups and cultural contexts. Empathy has been linked to defending behavior in children as young as 46.7 months (Swit et al., 2023). Similarly, empathy was associated with defending behavior in young Chinese children (mean age = 66.85 months) (Zhou et al., 2024) and in Spanish students in grades 3 to 6 (mean age = 9.8 years) (Lucas-Molina et al., 2018). Empathy has also been shown to be positively associ- ated with defending behavior in Italian youth (mean age = 13.2 years) (Gini et al., 2007) and American adolescents (Yun & Graham, 2018). Additionally, youth (mean age = 12.15) who engage in defending behavior appear to exhibit both cognitive and affective empathy (Lambe & Craig, 2020). A meta-analysis of 20 studies found a moderate positive association between empathy and defending behavior (Nickerson et al., 2015), similarly a systematic review of 40 studies concluded that both cognitive and affective empathy were consistently positively re- lated to defending (van Noorden et al., 2015). Another systematic review of 130 studies con- cluded both cognitive and affective empathy being positively associated with defending (Lambe et al., 2019). However, in this study, we are specifically interested in empathy as a predictor of defending behavior over time. In addition to the well-established concurrent positive association, empa- thy has also been found to predict defending behavior longitudinally, although some studies have examined affective and cognitive empathy separately. Affective empathy has been found to predict self-reported defending behavior over time in girls (Barchia & Bussey, 2011). Addi- tionally, both affective and cognitive empathy were positively associated with peer-reported 9 defending behavior seven months later among Finnish 4th to 6th graders (van der Ploeg et al., 2017); however, only affective empathy remained a significant predictor after controlling for gender, self-efficacy to defend, and previous defending. Nevertheless, given the meta-analytic findings showing a positive concurrent association between both types of empathy and de- fending behavior (Nickerson et al., 2015), and the limited longitudinal evidence available, we did not formulate separate hypotheses for affective and cognitive empathy. 1.3 The Moderating Role of Peer Likeability In addition to intrapersonal factors, interpersonal factors, such as youth’s likeability among their peers, may also play an important role in defending behavior (Lambe & Craig, 2020; Ma et al., 2019; Peets et al., 2015). Peer likeability generally refers to an individual’s acceptance and preference by peers (Lease et al., 2002; Parkhurst & Hopmeyer, 1998; Sandstrom & Cil- lessen, 2006). It is often assessed through sociometric procedures, such as peer nominations (e.g. Lease et al., 2002), which reflect how well-liked an individual is by their peers. Well- liked individuals tend to be low in aggression and dominance, and exhibit high levels of trust- worthiness and kindness (Parkhurst & Hopmeyer, 1998). They are also often characterized by sociability (Sandstrom & Cillessen, 2006). Peer likeability has also been associated with strong and supportive peer relationships. Well-liked individuals exhibit intrapersonal warmth and kindness (Gifford-Smith & Brownell, 2003), accompanied with cooperative behavior (Rubin et al., 1998). Peer likeability is particularly relevant to examine in relation to the prospective association between empathy and defending, as prior evidence supports that being well-liked is positively associated with prosocial behavior (Warden & MacKinnon, 2003). Recent findings further in- dicate that individuals who defend their peers tend to be well-liked (Laninga-Wijnen et al., 2023), and that likeability itself is linked to a higher likelihood of engaging in defending be- havior (Caravita et al., 2009; Salmivalli et al., 1996). Therefore, well-liked students may be more inclined and socially positioned to act on their empathy and support victimized peers. While there is some evidence supporting the prospective association between empathy and defending behavior, less is known about the interpersonal circumstances under which this link is evident. In addition, most prior research has examined peer likeability as a concurrent pre- dictor of defending (Laninga-Wijnen et al., 2023; Salmivalli et al., 1996; Warden & MacKin- non, 2003), but not as a potential moderator. Notably, social preference has been found to moderate the link between affective empathy and defending (Caravita et al., 2009), although 10 only in boys and in a cross-sectional setting. Moreover, peer likeability has rarely been exam- ined as a moderator in a longitudinal framework, limiting understanding of how one’s social standing may influence the likelihood of engaging in defending behavior over time. Thus, this study aims to offer understanding of under which circumstances empathy translates into de- fending. 11 2 Aims and Hypothesis Given the complexity of defending behavior and its underlying factors, it is essential to exam- ine whether empathy serves as a predictor of defending and whether peer likeability moder- ates this association over time. Therefore, the aim of this study is to investigate the prospec- tive association between empathy and defending behavior to provide evidence on the possible direction of the association. Specifically, the interest of this study is whether higher levels of empathy predict higher levels of defending behavior over time. In addition, the study exam- ines whether peer likeability moderates this longitudinal association, which has not yet been examined. This study aims to answer the following questions. 1. Is empathy positively associated with defending behavior over time? 2. Does peer likeability moderate the prospective association between empathy and de- fending behavior? Based on previous research, the following hypotheses are set. 1. Empathy is positively associated with defending behavior over time. 2. Peer likeability positively moderates the prospective association between empathy and defending behavior, with a stronger positive association expected among individuals with higher peer likeability. There is no longitudinal research on the moderating role of peer likeability in the association between empathy and defending behavior. Also, by examining peer likeability as a moderator, we address the question of whether interpersonal factors impact whether or not empathy leads to defending behavior over time. 12 3 Method 3.1 Participants This study is conducted utilizing previously collected data as part of the CHALLENGE pro- ject within INVEST Psychology at the University of Turku. Altogether, 6265 participants from Finnish schools in grades 1-9 took part in the data collection, from which we only fo- cused on grades 4 to 9 because participants in grades 1 to 3 (n = 2590) completed a shorter questionnaire that did not include all of the relevant study variables (such as defending). The starting sample before implementing inclusion and exclusion criteria was 3675 partici- pants. From these 3675 participants, 2 were excluded since they had missing data on defend- ing at both timepoints and imputing that data would not have been accurate. After this, 3673 participants were included. The sample consisted of participants on average born between 2005 and 2010. However, some participants may have started school later, repeated a grade or advanced in school earlier, leading to deviations in the birth years from the average grade- level mean. To address this, a ±2-year threshold from the grade-level mean was established to ensure participants matched expected age norms. Consequently, 11 participants were ex- cluded because of their age deviation. While these deviations may have been due to data entry errors, these exclusions ensured analytical accuracy and integrity. After excluding 13 partici- pants (0.35%), the final sample included 3662 participants (99.65%). As a result, the final sample included a total of 3662 participants in grades 4 to 9 (Mage = 13.05 years, SD = 1.68, [8.61, 16.89]). Altogether, 42.98% of the participants were in primary school (grades 4-6, n = 1574) and 57.02% of the participants in secondary school (grades 7-9, n = 2088). Of the total sample, 49.70% (n = 1820) identified as girls, 46.86% (n = 1716) as boys, 1.06% (n = 39) as nonbinary, and 2.38% (n = 87) chose not to disclose their gender. 3.2 Research Ethics This study was conducted utilizing previously collected data as part of the Challenge project within INVEST Psychology funded by the European Research Council. All ethical principles outlined in the Declaration of Helsinki were followed, including respect for autonomy, benefi- cence, and confidentiality (World Medical Association, 2025). Parental consent and informed assent from participants were obtained. Students were included in the nomination lists even if they did not participate in the study, meaning they could be nominated by classmates, but data 13 was not collected from them, which was approved by the ethics board. Participants were in- formed of their voluntary participation and right to withdraw at any time. No incentives were offered, and participation had no consequences for school-related outcomes. Throughout the study, data has been handled securely and respecting the privacy of the partic- ipants. To protect participants’ anonymity, all identifying information was securely stored separately from the pseudonymized data, which included non-identifying participant IDs. Thus, the anonymity of the participants was confirmed. 3.3 Procedure 3.3.1 Data Collection This study uses data collected as part of the CHALLENGE project. Data was collected from Finnish schools. Data collection occurred in seven waves over the course of three academic years (Wave 1 – October 2020, Wave 2 – February 2021, Wave 3 – May 2021, Wave 4 – Oc- tober 2021, Wave 5 – February 2022, Wave 6 – May 2022, Wave 7 – February 2023). The current study utilizes data from Wave 1 and Wave 3 (henceforth referred to as T1 and T2, re- spectively), as these waves included measures regarding youth’s defending behaviors. Participants completed self-report questionnaires and peer nominations online at school under the supervision of classroom teachers, who received detailed instructions about the data col- lection procedure. For peer nominations items, participants were asked which classmates best fit the descriptions. The participants were provided with a list containing names of their class- mates from which they could select as many classmates as they wanted for all peer nomina- tion items. They were also presented an option to select “nobody” or to skip the question. Par- ticipants could not nominate themselves. 3.4 Measures 3.4.1 Outcome Variable Defending at T2 was assessed with five peer nomination items. Five items were presented to the participants describing behaviors of defending (Who in your class acts like this in bullying situations?: “Consoles the victim afterwards.” “Is friendly towards the victim.” “Tries to make others stop the bullying.” “Gets angry at the bully(ies).” “Reports the bullying to an adult.”). 14 A proportional score for each participant was computed by dividing the sum of received nom- inations by the number of possible nominators in each class. Proportional defending scores ranged from 0 to 1. Defending at T2 had excellent internal consistency (Cronbach’s α = 0.91, McDonald’s ω = 0.93). 3.4.2 Main Predictor The main predictor empathy was measured using the Basic Empathy Scale (BES; Jolliffe & Farrington, 2006), which is one of the most widely used instruments to measure empathy throughout the world (Cabedo-Peris et al., 2021). The scale includes statements that the par- ticipants are asked to rate their level of agreement with. The response scale varies from 1 (strongly disagree) to 6 (strongly agree). The scale consists of 20 items of which eight items (1, 6, 7, 8, 13, 18, 19, and 20) were reverse coded. The higher the score the respondent re- ceives, the higher the level of empathy interpreted. Given that we did not have separate hy- potheses for affective and cognitive dimensions, the mean of all 20 empathy items was in- spected. Basic Empathy Scale demonstrated good internal consistency (Cronbach’s α = 0.87, McDonald’s ω = 0.90). 3.4.3 Moderator Peer likeability was assessed with the peer nomination item: “Who do you like the most?”. A proportion score for peer likeability was calculated for each participant by dividing the num- ber of nominations received by the total number of potential nominators. The number of pos- sible nominators was retrieved by computing participants with both consent and assent and then calculating this sum for each classroom, subtracting one as they were not able to name themselves. 3.4.4 Control Variables Three control variables were included to distinguish the effects of empathy and peer likeabil- ity on subsequent defending behavior. The chosen control variables include gender, grade level and the outcome variable (defending) at T1. Gender. Participants reported their gender (1 = “girl”, 2 = “boy”, 3 = “non-binary”, 4 = “I don’t not want to answer”). 15 Grade level. Participants’ grade level is a categorical variable, ranging from 4 to 9. Participants in mixed-grade classes were assigned the mean grade level value of the two re- spective grades. Defending at T1. Defending at T1 was assessed using the same procedure as at T2. De- fending at T1 had excellent internal consistency by Cronbach’s Alpha (α = 0.90), and McDonald’s omega (ω = 0.92). 16 4 Analytic Plan 4.1 Data Preparation The data were handled and analyzed using the RStudio program in R Statistical Software (R Core Team, 2024), using the tidyverse suite of packages (Wickham et al., 2019). The final sample after exclusion and inclusion criteria implemented comprised of 3662 participants. For these participants, missing values were handled, which is described in greater detail below. After handling the missing values in the data, the reverse coding for specific empathy items was applied (items 1, 6, 7, 8, 13, 18, 19, and 20). Summary variables for empathy, defending T1, and defending T2 were computed as the mean of their respective items: 20 items for em- pathy, and 5 items each for defending T1 and T2. Lastly, the means of empathy, peer likeabil- ity and defending at T1 were grand mean centered to address multicollinearity. 4.2 Handling of Missing Values Multiple imputation was utilized to handle missing values on the outcome, predictor, and con- trol variables, to include the majority of the participants. The imputation was carried out with a sample of 3662 participants. Of the participants, some had missing values in empathy, defending at T1 and T2, and peer likeability (altogether 10 639 of 109 860 individual values). This accounted for 9.68% of the values of interest missing, which were imputed following the steps described below. The chosen imputation method was Multiple Imputation by Chained Equations (MICE), im- plemented in RStudio using the mice package (Buuren & Groothuis-Oudshoorn, 2011). Multi- ple imputation (MI) is a robust and reliable tool for handling missing data, outperforming list- wise deletion and similar approaches across varying missingness rates (Janssen et al., 2010; Knol et al., 2010). Unlike single imputation methods, MI can generate multiple complete da- tasets, with each imputed value based on the observed data distribution (Roth, 1994), which would enhance the reliability of results, especially given the persistent issue of missingness in psychological research. Due to practical limitations, one imputed dataset was created for this study, which still offers a valid basis for analysis. MI as the chosen method still preserves the original variability and distribution shape, maintaining statistical integrity (Little, 1988). Fur- thermore, MI is well-suited for datasets containing both continuous and categorical variables, as it can model complex relationships between multiple variables (Wulff & Ejlskov, 2017). 17 The selected imputation method within MICE was Predictive Mean Matching (PMM), which replaces missing values with observed values from the existing data rather than generating synthetic predictions. The number of iterations was set to 50, allowing MICE to cycle through the chained equations multiple times to ensure convergence and stable imputations. After im- putation, the results were examined to ensure that all imputed values fell within the logical and expected ranges for each variable (as advised e.g., Little, 1988). 4.3 Main Analyses The analysis was conducted using RStudio. The method that was opted for the analysis is multilevel regression analysis with moderation, an extension of linear regression, which was chosen to take the hierarchical nature of the data into account. This multilevel approach was employed because previous research has shown that variation in defending behavior can be attributed to differences at the classroom level (Peets et al., 2015). Analyses were run using the lme4 package (Bates et al., 2015); mixed-effect model (LMER) for continuous variables. The packages utilized to generate the plots in RStudio were sjPlot (Lüdecke, 2024) and ggplot2 (Wickham, 2016). A series of multilevel models were conducted with defending behavior at T2 as a dependent variable. Grade level, student’s gender, and defending behavior at T1 were included in the analyses as control variables. Model 1 examined defending behavior at T2 predicted by the main predictor empathy T1 and the control variables grade level, gender, and defending be- havior at T1. In the second step, the main effect of peer likeability at T1 was added (Model 2). In the third step, interaction term between empathy T1 and peer likeability T1 was added (Model 3) to examine whether peer likeability moderates an association between empathy T1 and defending T2. In all models, classroom was included as a random effect to account for group-level variation. For the interaction term, empathy and peer likeability were grand-mean centered. To reduce multicollinearity, defending at T1 was also grand-mean centered. 18 5 Results 5.1 Descriptive Statistics and Preliminary Analyses Descriptive statistics and correlations are presented in Table 1. There was a weak positive as- sociation between empathy at T1 and defending at T2. In addition, weak but significant posi- tive associations were shown between empathy T1 and peer likeability T1, and peer likeabil- ity T1 and defending T2. A moderate negative association was observed between defending at T2 and grade level, suggesting higher levels of peer-reported defending in younger grades. There was also a strong positive association between defending T1 and T2. Correlations among other predictors were weak. Variance Inflation Factor (VIF) values were calculated for all predictors in the models to as- sess multicollinearity (the car package; Fox & Weisberg, 2019). The VIFs for variables were within acceptable ranges, with empathy showing a VIF of 1.23 and peer likeability a VIF of 1.15. The interaction term of empathy and peer likeability had a VIF of 1.02. Grade level showed a VIF of 1.07, gender a VIF of 1.40, and defending at T1 a VIF of 1.44. Thus, multi- collinearity was not a concern in the models. The assumption of normality was assessed using the Shapiro-Wilk normality test. The test re- vealed a significant deviation from normality for the response variable, defending at T2 (W = TABLE 1 Descriptive Statistics and Correlations for Study Variables Variable 1. 2. 3. 4. 5. M (SD) 1. Defending T2 - 0.14 (0.15) 2. Defending T1 .76*** - 0.17 (0.16) 3. Peer Likeability .30*** .36*** - 0 (0.18) 4. Grade Level -.51*** -.51*** -.20*** - - 5. Gender -.20*** -.21*** -.03 .02 - 6. Empathy .17*** .20*** .05** .05** -.37*** 0 (0.70) *p < .05. **p < .01. ***p < .001. 19 0.86, p < .001), indicating a heavily skewed distribution. Indeed, many participants received a “0” for defending at T2. Considering the large sample size and previous studies often treating peer-reported defending as a continuous variable despite its skewed distribution (e.g., Lucas- Molina et al., 2018; Yun & Graham, 2018), we chose to apply linear approach in the main analyses rather than categorizing defending, to maintain comparability with prior research. 5.2 Main Analyses The results of the multilevel linear regression analyses are presented in Table 2 (see Appendix 1) with unstandardized regression coefficients, standard errors, 95% confidence levels, and p- values for each predictor. Additionally, the conditional and marginal R2, Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), and ICC for each model are reported. The null model, which included only a random effect for classroom, explained 70,87% (R2 = 0.7087) of the variance, suggesting that a large proportion of the variance in the defending be- havior was explained by differences at the classroom level. Adding empathy at T1, control variables (grade level, gender and prior defending behavior), and a random effect for the classroom in Model 1 significantly improved the fit compared to the null model (χ2 (6) = 1849.80, p < .001). Together, these variables explained 53.4% of the variance in defending behavior at T2. Empathy at T1 was positively and significantly associated with defending at T2 (p = .02). Of the control variables defending at T1 was significantly positively associated (p < .001) and grade level significantly negatively associated (p < .001) with defending at T2. With girls as the reference group, being a boy was significantly negatively associated with de- fending at T2 (p < .001), indicating that girls were more likely to defend than boys. Model 2, including peer likeability at T1, explained 53.3% of the variance in the outcome var- iable; however, it did not significantly improve the model (χ2(1) = 2.86, p = .09). Moreover, peer likeability at T1 was not significantly associated with defending at T2 (p = .09). The pos- itive effect of empathy on defending T2, however, remained significant (p = .03). The pattern of associations for the control variables remained similar to that observed in Model 1. In Model 3, an interaction between empathy and peer likeability was added to Model 2. Model 3 explained 53.4% of the variance in outcome variable and significantly improved the model (χ2(1) = 16.04, p < .001). Peer likeability moderated the association between empathy and defending behavior (p < .001). Examination of simple slopes (Fig. 1) revealed that empa- thy at T1 was positively associated with defending behavior at T1 among students with high 20 (B = 0.01, SE = 0.00, t(221) = 4.38, p < .001) and average levels of peer likeability (B = 0.00, SE = 0.00, t(221) = 2.43, p = .02), but not among students at low level of peer likeability (B = −0.00, SE = 0.00, t(221) = −0.88, p = .38). A similar pattern of associations for the control variables was observed as in Models 1 and 2. FIGURE 1. The moderating effect of peer likeability at T1 on the association between empa- thy at T1 and defending at T2. *p < .05. **p < .01. ***p < .001. -1 SD Mean +1 SD 21 6 Discussion Previous research, including a meta-analysis (Nickerson et al., 2015), has found a positive, concurrent association between empathy and defending. However, limited research has exam- ined prospective associations between empathy and defending, which is needed to clarify the direction of the association. This is a crucial gap, as defending is an important behavior that can help reduce bullying in the peer group (Nocentini et al., 2013), making it critical to under- stand under which circumstances youth are more likely to defend their peers. Therefore, in the current study, we examined the longitudinal association between empathy and defending be- havior. We further extended previous research by examining the moderating role of peer like- ability, as it is important to understand how contextual interpersonal factors may impact the empathy-defending link. 6.1 Prospective Associations Between Empathy and Defending Consistent with the limited previous longitudinal studies (Barchia & Bussey, 2011; van der Ploeg et al., 2017), we found a positive longitudinal association between empathy and defend- ing behavior. Thus, the current study provides important insight into the directionality of this association, suggesting that higher levels of empathy may predict subsequent defending be- havior. One plausible explanation is that empathetic youth may be more attuned to others’ dis- tress, as empathy is an emotional response in the observer (Eisenberg et al., 2015; Trach et al., 2023). Observing others’ distress may enhance youth’s motivation on alleviating the per- ceived distress (Batson et al., 1997; Batson & Shaw, 1991), but possibly only when their con- cern for others is stronger than their own distress (Carrera et al., 2013). The results suggest empathy may be a key factor in youth defending their peers, implying that fostering empathy development might in turn lead to more defending. Therefore, future stud- ies could examine whether interventions targeting children’s empathic abilities lead to in- creased defending behavior over time. 6.2 The Moderating Role of Peer Likeability However, in the current study, we found that the main association between empathy and de- fending depended on youth’s social standing – specifically, peer likeability. We found that empathy was positively associated with defending over time for youth who with high or aver- age levels of peer likeability, but not for those who were low in peer likeability. Prior research 22 has shown that the concurrent empathy-defending association is stronger among youth with high social preference (Caravita et al., 2009), sometimes used interchangeably with peer like- ability (Gifford-Smith & Brownell, 2003). Our findings are consistent with these results, sug- gesting that empathy alone may not translate into prosocial action without the supportive in- trapersonal circumstances. The reason for the moderating role of peer likeability might lie in that empathy itself may not always be enough to initiate prosocial action (Eisenberg et al., 2015), for example because of defenders’ concerns that they may be putting themselves at risk of victimization (Strindberg et al., 2020). However, well-liked individuals seem to be less likely to become victimized (Bu- kowski et al., 2010), and thus might not be as afraid of defending their peers. Likeability has also been associated with stronger friendships (Rubin et al., 1998; Sandstrom & Cillessen, 2006), so these youth may have more support in the peer group, allowing them to defend more. Thus, some individuals high in empathy may want to defend, but refrain from doing so due to a fear of becoming victimized themselves, a concern that well-liked peers might be less susceptible to. Although the association between empathy and defending was positive and significant for both well-liked and moderately liked youth, this link was stronger for those who were well- liked. One possibility is that being moderately liked may not provide the same feeling of so- cial security to engage in defending behavior. For example, the stronger association for well- liked students may partly reflect their possession of other social resources or other forms of social status, such as perceived popularity, which has also been linked to defending and its in- terpersonal underpinnings (Pöyhönen et al., 2010). Well-liked students may thus feel secure enough in their social standing to even defend classmates that they are not friends with, as they have the social power to act against bullies (Juvonen & Galvan, 2008). Furthermore, moderately liked students may defend their victimized friends but not classmates they are less close to (Bellmore et al., 2012; Meter & Card, 2015), possibly due to feeling less secure about their social standing. Of note, as demonstrated in Figure 1, when empathy is low, youth with low peer likeability appear to have higher levels of defending than youth with average or high peer likeability. One possible explanation is that these youth may be engaging in aggressive forms of defend- ing, which have been linked to lower levels of empathy and peer preference, and higher levels of aggression (Wang et al., 2023). Furthermore, low empathy has been associated with higher 23 levels of aggressive behavior (Jolliffe & Farrington, 2004), and aggressiveness with direct ways of intervening (Lambe & Craig, 2020). There is also evidence of overlap between being a target and a perpetrator in bullying situations (eg. Chan & Wong, 2015; Posick & Zimmer- man, 2015). Thus, less empathetic and less liked youth who engage in defending behavior may represent a subgroup that alternates between these roles, and possibly even engages in defending across different bullying contexts. Their involvement in multiple roles may reflect a pattern of engagement in peer conflict, such as aggressive defending, potentially driven by a tendency of reactive behavior. 6.3 Strengths, Limitations, and Future Directions 6.3.1 Strengths This study has important strengths, including its longitudinal design and the use of modera- tion analysis, which help clarify the directional association between empathy and defending, as well as identify the conditions under which empathy is more likely to be associated with defending behavior over time. In addition, the current study examines a large sample from multiple grade levels and schools across Finland, resulting in a representative sample of the country. We also used a multilevel design to account for participants being nested within classrooms, which strengthens the study by controlling for classroom level differences, for ex- ample in victimization rates and group-level norms, providing more precise and sensitive esti- mates of the studied associations. In addition, this study utilized peer-reports of defending and peer likeability as they are less susceptible to social desirability biases and because they utilize multiple informants (i.e., mul- tiple classmates vs. single informant self-report) (Branson & Cornell, 2009; Lambe & Craig, 2020). However, we also measured empathy with a reliable self-report survey (BES; Jolliffe & Farrington, 2006), which mitigates the same-source bias, as our predictor and outcome were assessed with different informants (self and peer, respectively). 6.3.2 Limitations and Future Directions Despite the notable strengths of this study, it also has limitations that need to be addressed. First, due to a shorter questionnaire provided to students in grades 1 to 3, the study sample in- cluded only students from grades 4 to 9. Therefore, these results cannot be directly applied to young children, limiting the generalizability of the findings. Given that peers become more 24 important to youth in later childhood and early adolescence (Buhrmester & Furman, 1987; Nickerson & Nagle, 2005), it is possible that moderators other than peer likeability may be more relevant for younger children. Future research should consider a broader age range to also capture developmental differences. Second, the study relied solely on peer nominations to measure defending behavior and peer likeability. Peer-reports of defending reflect youth’s reputation in the peer group as someone who defends, while avoiding overreporting defending prevalence and social desirability bias that may arise from self-reports. However, a higher number of nominations does not neces- sarily indicate greater frequency or quality of defending behavior, which needs to be consid- ered when interpreting the findings. In addition, despite the strengths of peer nominations, other forms of peer-reports, such as peer ratings (i.e., each participant rates each classmate), could offer a more complete view of peer group dynamics (Gifford-Smith & Brownell, 2003). Likewise, measuring peer likeability through nominations reflects general likeability but does not capture the peer rejection of the student or the quality of social interactions. It is also pos- sible that well-liked participants also received more defending nominations due to the same source bias. Consistent with prior research demonstrating weak to moderate concordance be- tween self-, teacher-, and peer-reports on loneliness (Geukens et al., 2021), bullying (Branson & Cornell, 2009), and peer status (van den Berg et al., 2015), future studies should consider multiple informants of defending and peer likeability for a more comprehensive assessment. Third, the study did not include victimization as a control variable, which could have implica- tions for defending. Participants in classrooms with low levels of victimization may have re- ceived fewer nominations on defending. For example, in the current sample participants in higher grade levels exhibited less defending behavior, which may result from lower levels of victimization in secondary than primary school (Kärnä et al., 2011; Pellegrini & Long, 2002). Due to possible classroom level differences, we conducted multilevel analyses. However, fu- ture studies could include also victimization as a control. 25 7 Conclusions The results from the current study provided support for both of the hypotheses. Empathy was positively associated with defending behavior over time, and this association was moderated by peer likeability. Specifically, empathy was positively associated with defending over time, for students with at least average levels of likeability, but not those with low levels of likea- bility. Our findings, which indicate that higher empathy is related with elevated defending over time and that this association depends on youth’s social standing, extend prior research demon- strating only concurrent associations between empathy and defending. Defending seems to be effective in reducing bullying in the peer group (Nocentini et al., 2013), but still remains rela- tively rare (Ma et al., 2019), possibly because defenders are taking a risk when helping vic- timized peers (Do et al., 2017). However, fostering empathy in youth may promote prosocial intentions and encourage defending, particularly among youth with at least moderate social standing. This may be especially relevant for well-liked youth, who could use their social in- fluence in peer relations to promote prosocial behavior (as defending) (Laursen et al., 2023), thereby shaping the social norms around bullying (Dijkstra et al., 2008). This is particularly important, as defended victims experience better psychological adjust- ment, including lower depressed mood, greater positive mood, and less self-blame (Laninga- Wijnen et al., 2024), and also report better self-esteem, greater peer acceptance, and less re- jection than undefended victims (Sainio et al., 2011). 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Journal of Psychology in Africa, 34(1), 1–6. https://doi.org/10.1080/14330237.2024.2311987 36 Appendices Appendix 1: Table 2 Multilevel Linear Regression Models TABLE 2 Linear Regression Models of Predictors of Defending at T2 Model 1 Model 2 Model 3 Predictors B SE 95% Cl p B SE 95% Cl p B SE 95% Cl p (Intercept) 0.26 0.02 [0.22, 0.30] <.001 0.26 0.02 [0.22, 0.30] <.001 0.26 0.02 [0.22, 0.30] <.001 Grade Level -0.02 0.00 [-0.02, -0.01] <.001 -0.02 0.00 [-0.02, -0.01] <.001 -0.02 0.00 [-0.02, -0.01] <.001 Gender - Boy -0.02 0.00 [-0.02, -0.01] <.001 -0.02 0.00 [-0.02, -0.01] <.001 -0.02 0.00 [-0.02, -0.01] <.001 Gender - Nonbinary -0.01 0.01 [-0.04, 0.01] .19 -0.01 0.01 [-0.04, 0.01] .22 -0.01 0.01 [-0.04, 0.01] .19 Gender - No Answer -0.01 0.01 [-0.03, 0.00] .10 -0.01 0.01 [-0.03, 0.00] .10 -0.01 0.01 [-0.03, 0.00] .084 Empathy 0.00 0.00 [0.00, 0.01] .022 0.00 0.00 [0.00, 0.01] .03 0.00 0.00 [0.00, 0.01] .015 Defending T1 0.54 0.01 [0.51, 0.57] <.001 0.53 0.01 [0.50, 0.56] <.001 0.53 0.01 [0.50, 0.56] <.001 Peer Likeability 0.01 0.01 [0.00, 0.03] 0.09 0.02 0.01 [0.00, 0.03] .051 Empathy x Likeability 0.04 0.01 [0.02, 0.06] <.001 37 TABLE 2 (continued) Random Effects σ2 0.00 0.00 0.00 τ00 0.01class 0.01class 0.01class ICC 0.57 0.57 0.57 N 351class 351class 351class Observations 3662 3662 3662 Marginal R2 / Conditional R2 0.534/ 0.801 0.533/ 0.801 0.534/ 0.801 AIC / BIC -8644.90/ -8589.05 -8638.02/ -8575.97 -8644.50/ -8576.24 Note: Gender was dummy coded with "Girl" as the reference group. AICs and BICs are fitted with REML.