Birth Orders Effect on Non-Suicidal Self-Injury and Perceived Parental Support

Birth Orders Effect on Non-Suicidal Self-Injury and Perceived Parental Support Delila Kadric & Ludvig Löfquist

Örebro University

Abstract

In this study we investigated the effects of birth order and gender on non-suicidal self-injury and perceived parental support. This study’s main purpose was to challenge the current use of birth order in psychology. The study included a short questionnaire assessing birth order, gender, perceived parental support and non-suicidal self-injury. The questionnaire was distributed through an online survey among young adults attending a university in a medium sized city in Sweden (N = 202). To explore the perceived parental support, we used The Social Provisions scale and non-suicidal self-injury was assessed by the Deliberate Self-harm Inventory, short 9-item scale. The results of these studies showed that birth order had no significant effect on non-suicidal self-injury or perceived parental support. On the other hand, the results suggested that gender had a significant effect on non-suicidal self-injury, with females engaging on non-suicidal injury more frequently than men. This contradicts earlier studies where no effect of gender has been present in young adults. Gender had no apparent effect on perceived parental support.

Keywords: non-suicidal self-injury, perceived parental support, birth order, gender

Supervisor: Reza Kormi-Nouri Psychology III

Placering i syskonskarans effekt på icke-suicidalt självskadebeteende och upplevt föräldrastöd Delila Kadric & Ludvig Löfquist

Örebro Universitet

Sammanfattning

I denna studie undersökte vi effekten av placering i syskonskaran och kön på icke-suicidalt självskadebeteende och upplevt föräldrastöd. Denna studies huvudsyfte var att utmana hur placeringen i syskonskaran används i psykologi. Studien inkluderade ett kortare frågeformulär som mätte placering i syskonskaran, kön, upplevt föräldrastöd och icke-suicidalt självskadebeteende. Frågeformuläret delades ut genom en online-baserad undersökning för unga vuxna som studerar på ett universitet i en medelstor svensk stad (N = 202). För att undersöka upplevt föräldrastöd använde vi oss av The Social Provisions scale och icke-suicidalt självskadebeteende undersöktes av Deliberate Self-harm Inventory, short 9-item scale. Resultatet av denna studie visade att placering i syskonskaran inte hade några signifikanta effekter på varken icke-suicidalt självskadebeteende eller upplevt föräldrastöd. Dock visade det sig att kön hade en effekt på icke-suicidalt självskadebeteende, då kvinnor hade en högre prevalens att praktisera än män. Kön hade ingen uppenbar effekt på upplevt föräldrastöd.

Nyckelord: icke-suicidalt självskadebeteende, upplevt föräldrastöd, placering i syskonskaran, kön

Birth Orders Effect on Non-Suicidal Self-Injury and Perceived Parental Support In western popular culture birth order is often used to explain how a person develops a wide array of different personality traits. For example, it is not unusual that newspapers write articles about how being an older child make you more prior to develop different personality traits than your younger siblings. Frank Sulloway (1996), the author of the book Born to Rebel: Birth Order, Family Dynamics, and Creative Lives, claims an excessive association between birth order and personality traits. In his book he writes about how firstborn children already have a set role in the family and therefore tend to develop personality traits that reflect responsibility and competitiveness. Later born children, on the other hand, need to create their own role and differentiate themselves - and therefore become more rebellious and playful. Even though Sulloway's literature is widely used in popular culture and considered by many as fact, newly conducted research has showed that birth order has no effect on a person’s personality at all (Rohrer, Egloff, & Schmukle, 2015).

Birth Order

When looking into birth order there seems to be two main trains of thoughts on how it affects siblings being different from each other. The first one, which we just discussed, is that the individual fits into an already set role (Sulloway, 1996). The other one is that the

individuals receive different parental support depending on whether they are first born or later born (Gottlieb & Mendelson, 1990). The theory including parental support has not received as attention as the first one, which is why it was implemented into this study.

Research conducted by Nyman (1995) showed that the general public believes that being born first, and the assumed traits that come with that, is the most favorable birth position. But is this really the case? Does birth order have a direct impact on the life of an individual? As previously mentioned the research conducted by Rohrer et al. (2015) debunked that birth order had any effect on personality, but what is interesting is that they also found

significant results for birth order on other variables. For instance, they stated that birth order has a significant effect on intelligence, saying that firstborns have a slightly higher intellect than later-born children (Rohrer et al., 2015). Another study (Barclay, Myrskylä, Tynelius, Berglind, & Rasmussen, 2016) has shown that being born later than your siblings gives you disadvantages in life, for example you are more likely to be hospitalized for alcohol or narcotic use. Salmon, Shackelford and Michalski (2011) have found that first- and last born children reported being favored by their parents, which implies that there are differences in how parents favor their children depending on birth order.

To the best of our knowledge there is still a great gap when it comes to empirical research conducted on birth order, and especially when linking it to non-suicidal self-injury and perceived parental support.

Non-suicidal Self-injury

Non-suicidal self-injury is a growing public health problem across the globe (Nock & Prinstein, 2004), and has been included in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), where it is stated that non-suicidal self-injury is a condition that stands in need for future research (American Psychiatric Association, 2013).

Non-suicidal self-injury affects an individual both physically and psychologically. Researchers Klonsky and Muehlenkamp (2007) state that non-suicidal self-injury is when an individual purposefully destructs their own body without any suicidal intent, which is more often practiced by youths than adults. They also describe that non-suicidal self-injury can occur in different forms, e.g. cutting, burning or hitting oneself. Even though most self-injury is to ease strong negative feelings it can also be performed because of self-disgust or anger, or to repel suicidal thoughts. Previous research suggests that non-suicidal self-injury has

negative effects on an individual, those effects include interpersonal difficulties (Tatnell, Kelada, Hasking, & Martin, 2014), negative mood and interpersonal conflicts (Nock,

Prinstein, & Sterba, 2009) and an increased risk for suicide (Klonsky, May, & Glenn, 2013). In conclusion non-suicidal self-injury affects you both physically and psychologically.

The onset of non-suicidal self-injury usually starts in adolescence (Glenn & Klonsky, 2011; Hankin & Abela, 2011; Klonsky, 2011) and decreases throughout late adolescence and young adulthood (García-Nieto, Carballo, de Neira Hernando, de León-Martinez, & Baca-García, 2015; Jacobson & Gould, 2007), which is why we focus on young adults.

Perceived Parental Support and Non-suicidal Self-injury

Parental support is important for an individual to avoid self-injurious behavior. Parental support as a basic psychological need has been suggested to be positively related to the mental health of children and adolescents (Grolnick, Price, Beiswenger, & Sauck, 2007). Another earlier study (Martin, Bureau, Cloutier, & Lafontaine, 2011) suggested that

individuals with thoughts of non-suicidal self-injury, and those who actually engage in actions of non-suicidal self-injury, reported poorer relationships with their parents than individuals that do not engage in non-suicidal self-injury at all. Previous research (Claes, Luyckx, Baetens, Van de Ven, & Witteman, 2015) showed that non-suicidal self-injury is related to depression and moderated by parental support. For example, Emery, Heath and Rogers (2017) has shown that adolescents who perceive low parental autonomy support also have a harder time regulating their emotions, and therefore turn to non-suicidal self-injury as a coping strategy. Thus, parental support is an important factor for a person to avoid self-injurious behavior. Furthermore, it has been suggested that there are gender differences regarding emotion regulation, and therefore females and males have different coping strategies (Underwood, 1997). Moreover, Nielsen and Knardahl (2013) have suggested that coping strategies could be both stable and malleable over time.

Gender Differences in Non-suicidal Self-injury

in non-suicidal self-injury. For example, Guerry and Prinstein (2009) have suggested that females engage in non-suicidal self-injury more frequently than males, but Hilt, Cha and Nolen-Hoeksema (2008) did not find any gender difference in non-suicidal self-injury. Those studies that have found significant gender differences generally have focused on adolescents (Guerry & Prinstein, 2009; Laye-Gindhu & Schonert-Reichl, 2005; Muehlenkamp, Williams, Gutierrez, & Claes, 2009; Plener, Libal, Keller, Fegert, & Muehlenkamp, 2009; Ross & Heath, 2002; Yates, Tract, & Luthar, 2008). However, Heath, Schaub, Holly, and Nixon, (2009) did not find such differences among young adults. Hence, gender has been suggested to be a significant factor in adolescence but not in young adulthood.

Kristjánsson and Sigfúsdóttir (2010) have found gender differences in parental support. More specifically, males receive less parental support and less monitoring than females.

Purpose and research question

The main purpose of this study is to challenge the use of the birth order as an independent variable in social sciences. This since birth order seems to give inconclusive results

on

whether it can affect an individual’s personality or not(Barclay et al., 2016; Rohrer et al., 2015) and that its current usage seems outdated. We decided to include non-suicidal self-injury and perceived parental support in our study, since they have not been explained by birth order in previous studies. Non-suicidal self-injury in adolescence has widely been studied in earlier research, however studies on non-suicidal self-injury amongst young adults is a gap that we aimed to fill with our research approach. Furthermore, since previous research has found mixed results regarding gender differences in non-suicidal self-injury, we aimed to explore this variable further.

To examine whether birth order is a reliable variable we aimed to answer the two following questions. First, does birth order and gender have an effect on non-suicidal self-injury? Second, does birth order and gender have an effect on perceived parental support?

In this study we examined whether non-suicidal self-injury and perceived parental support can be explained by birth order among young adults. With birth order we mean whether you are a first born or a later born among your siblings. We also looked into the effect of gender, and how it is related to non-suicidal self-injury and perceived parental support.

Our hypothesis is that non-suicidal self-injury is not affected by birth order. We also did not think that perceived parental support is affected by birth order. Furthermore, we think that gender will have no effect amongst young adults on either perceived parental support or non-suicidal self-injury.

Method Participants

There were 202 participants in our study and out of them 133 identified as females (Mage = 22.02, SDage = 1.90), and 69 as males (Mage = 22.36, SDage = 1.95). The inclusion

criterion for our sample was that each participant was a young adult within the age range of 18 and 25. Out of the 202 participants, 79 were first born and 123 were later born. As compensation the participants were offered the opportunity to win a gift card at SF bio. All young adults between the ages of 18 and 25 were encouraged to participate. We used

convenience sampling to find our participants, meaning that the sample of our study was not randomly selected, but consisted of participants that were all readily available for

Measures

To collect the data used in our study we used two separate scales measuring non-suicidal self-injury and perceived parental support respectively. The participants were also asked about their age, gender and birth order among their siblings.

Non-suicidal self-injury. Young adult’s non-suicidal self-injury was measured with the Deliberate Self-Harm Inventory, short 9-item scale (DSHI-9r) (Bjärehed & Lundh, 2008). Through DSHI-9r, the participants were asked whether they had deliberately engaged in any of the nine different self-injury behaviors during the past 6 months. The response scale for the items varied on a scale from 0 to 6, where 0 = never engaged in such behavior, and 6 = engaged in such behavior more than five times. To calculate the total score we added the number of times that each participant had engaged in such behavior, the total scored added up to a score range between 0 and 54. Following are some examples of items that are included in DSHI-9r: “Have you, during the last six months, cutting arms, wrists, or body areas?”, “Have you, during the last six months, biting self, so that the skin is broken?”, “Have you, during the last six months, banged your head and thereby causing a bruise?” Lastly, we asked our

participants an additional question where they indicated how many times that the self-harm that they had engaged in had resulted in them being hospitalized or having to seek medical treatment.

In this study the results showed a Cronbach's alpha value of .71. Furthermore, the reliability and construct validity of this scale has been reported before, with a Cronbach’s alpha value of .90 (Bjärehed, Wångby-Lundh, & Lundh, 2011).

Perceived parental support. To examine young adult’s perceived parental support, we used a revised version of The Social Provisions scale (Cutrona, 1989; Cutrona & Russell,

1987). The scale included 24 items, four statements that assessed each of the six provisions which were originally identified by Weiss (1974); social integration, reassurance of worth,

guidance, attachment, opportunity of nurturance and reliable alliance. We decided to only include four of these provisions (reliable alliance, attachment, guidance and reassurance of worth), and therefore only included 16 statements. We rephrased the statements so they could be used to assess parental support, but they still had the same meaning. The response scale for the items varied on a scale from 1 to 4, where 1=strongly disagree and 4=strongly agree. Half of the items were in a positive form indicating that perceived parental support was present and the other half were reversed negatively indicating that perceived parental support was not present. Examples of positive items that were presented in the scale were: “I can depend on my parents to help me if I really need it” and” I can talk to my parents about important decisions in my life”. Examples of negative items that were presented in the scale were: “If something went wrong, my parents would not come to my assistance” and “I cannot turn to my parents for guidance in times of stress”. When calculating the total scores in

International Business Machines Corporation Statistical Package for the Social Sciences (IBM SPSS), the scores from the negative items were reversed so that they had the same value as the positive items. By adding the responses from each participant for all the items we got the total score. The interpretation of the total scores was as following; a high score indicated that the participant had a greater degree of perceived parental support, and a low score indicated that the participant had a lower degree of perceived parental support. The results from this study showed a Cronbach's alpha value of .94.

Procedure

The data that emerged from this study was collected through an online survey that we sent out via a Facebook group mainly occupied by young adult students. The survey was available for participation throughout one week.

Throughout the time of the study and the collection of the data we took into consideration the ethical issues in conducting research stated by Christensen (2015), by

informing the participants about the purpose of the study, and their role in the study. The participants were also informed that their participation was completely voluntary, and about any information that could have affected their willingness in participating in our study. Our participants were informed that they gave their consent by completing our questionnaire and that they participated in our study on their own terms, meaning that they had the right to end their participation in our study during their participation, without any negative consequences. Since our study involved ethically sensitive data regarding our participants, we ensured confidentiality by making sure that unauthorized individuals could not take part of the

emerged data. All the data was presented on a group level and was only used for the scientific purposes of this study.

Statistical Analyses

We analyzed the data from our study with IBM SPSS, which is a software designed for statistical analyses (Field, 2013).

We ran two separate factorial analysis of variance (ANOVA), since it enabled us to look at the effects of our two independent variables (birth order and gender) on respective dependent variables (non-suicidal self-injury and perceived parental support), and how these independent variables interact with each other. In this study, the factorial ANOVAs showed the main effects of birth order and gender on non-suicidal self-injury as well as on perceived parental support. Furthermore, the factorial ANOVA also showed the interaction effects of birth order and gender on non-suicidal self-injury as well as on perceived parental support. We further ran a simple regression analysis to see whether perceived parental support predicted non-suicidal self-injury, as it has in earlier findings.

Results

As mentioned before, we focused on young adults to investigate if non-suicidal self-injury and perceived parental support is affected by birth order among young adults. We also

looked into the effect of gender, and if it is related to non-suicidal self-injury and perceived parental support.

Table 1

Descriptive Statistics for Birth Order on Perceived Parental Support and Non-suicidal Self-injury

Perceived Parental Support Non-suicidal Self-injury First born n= 79 Later born n = 123 First born n = 79 Later born n = 123 M SD M SD M SD M SD Male 48.71 13.16 53.05 10.65 10.75 1.92 10.93 1.90 Female 54.28 8.89 53.04 10.54 12.24 5.15 12.21 4.64 Total 52.30 10.85 53.04 10.53 11.71 4.33 11.78 3.98

Note. M = Means, SD = Standard Deviation, N = number of participants

In Table 1 under perceived parental support we can see that first born females (M = 54.28) have reported higher values of support than males (M = 48.71). This difference does not exist amongst later born. When comparing first born males (M = 47.71) with later born males (M = 53.05)we can also see that the later born have scored higher in perceived parental support. This pattern was opposite for females. When looking upon non-suicidal self-injury in Table 1, we can see that females have reported higher levels of self-injury than males in both cases of birth order. There was no such difference between the two birth orders.

To analyze our descriptive data with an advanced statistic, we conducted two separate factorial ANOVAs for the perceived parental support and non-suicidal self-injury data.

The results of a factorial ANOVA with Birth order and Gender as the independent variable and Non-suicidal self-injury as the dependent variable showed that there was a significant main effect of gender, F (1,198) = 4.98, p < .05, η 2 = .03 on non-suicidal

self-injury. However, there was no effect for birth order F (1,198) = .01, p = .90 on non-suicidal self-injury. Through a post hoc analysis of Table 2 we can see that females engaged in more non-suicidal self-injury than males. There was no significant interaction effect, F (1,198) = .03, p = .80.

The results of another factorial ANOVA with Birth order and Gender as independent variable and perceived parental support as dependent variable showed that there were no significant main effects of neither birth order, F (1,198) = .93, p = .30, η 2 = .02 nor gender F (1,198) = 2.99, p >.05, η 2 = .01 on perceived parental support. Furthermore, there was no significant interaction effect either, F (1,198) = 3.02, p >.05, η 2 = .02. However, we can consider some tendency effects regarding the gender variable here.

This indicated that birth order has no plausible effect on a young adult’s self-injurious behavior. Even though it looked like there was a difference between the birth orders on perceived parental support (Table 1), this did not reach significance when running the factorial ANOVA. Gender explained non-suicidal self-injury, were women reported higher levels of non-suicidal self-injury than males in young adults. However, gender did not show any significant effect on perceived parental support.

The results of the simple regression showed that 6 % of the variance in non-suicidal self-injury was significantly explained by perceived parental support, F (1, 198) = 12.66, p < .001. Perceived parental support negatively predicted young adults engagement in non-suicidal self-injury, β = – .24, p < .001.

Discussion

Based on limitations observed in previous research, the purpose of this study was to investigate whether birth order or gender has an effect on non-suicidal self-injury and perceived parental support among young adults. The results of this study showed that birth order does not have significant effect on non-suicidal self-injury. This goes in line with

research conducted by Rohrer et al. (2015) where birth order showed no apparent effect on personality. Our results also showed that birth order has no effect on parental support. However, gender differences regarding non-suicidal self-injury were found.

According to earlier research on the gender differences in non-suicidal self-injury during adolescents, it has been suggested that females engage in non-suicidal self-injury more frequently than males (Guerry & Prinstein, 2009). Researchers have failed to find such

differences among young adults (Heath et al., 2009). However, in this study we found that females engage in non-suicidal self-injury more frequently than males in young adulthood. This infers that the gender differences in non-suicidal self-injury are stable over time, which contradicts earlier findings. However, these contradicting results could be due to our sample only consisting of university students. A speculation on why these results could be linked to our sample is that females who get a higher education perhaps stay with non-suicidal self-injury as a coping strategy where females who do not get a higher education find other

solutions to cope with their emotions as a result of different environments and life-conditions. Furthermore, it has been suggested that females and males have different coping strategies regarding their emotions, meaning that they manage and regulate emotions

differently (Underwood, 1997). This further suggests that it could be possible for females and males to manifest their non-suicidal self-injurious behavior in different ways and under different conditions.

Moreover, researchers Nielsen and Knardahl (2013) have suggested that coping strategies could be both stable and malleable over time which could be the reason as to why different researchers get different results in whether non-suicidal self-injury is persistent over time or not.

Our results suggest that perceived parental support predicts non-suicidal self-injury significantly, which goes in line with previous research (Martin et al., 2011). Previous

research suggested that adolescents with low perceived parental support turn to non-suicidal self-injury as a coping strategy (Emery et al., 2017), which could be the case for young adults as well. Consequently, young adults who do not perceive their parents as supportive have a harder time regulating their emotions, and therefore engage more in non-suicidal self-injury as a coping strategy. In the pursuit of preventing non-suicidal self-injury, further research is needed on why perceived parental support prevents engagement in non-suicidal self-injury.

In a previously mentioned study, it has been suggested that non-suicidal self-injury is moderated by parental support, where high parental support indicated lower levels of non-suicidal self-injury (Claes et al., 2015). This is interesting since women have been suggested to receive more parental support (Kristjánsson & Sigfúsdóttir, 2010), but also engage more in self-injurious behavior (Guerry & Prinstein, 2009). This can be because of the differences in emotional regulation and in coping strategies between the genders, indicating that female’s coping strategies are more self-injurious in nature than males. However, these speculations are based on previous research, since our results of genders effect on perceived parental support were not significant.

An aspect that we did not consider was how different types of family constellations can affect the reported perceived parental support. For example, the numbers of marriages that end up in divorce has increased during the last two decades (Eurostat, 2017) and back in 2012 half of the couples who took out a divorce had kids younger than 16 years of age (McLaren, 2012). This could lead to that the children grow up with different kinds of support every other week, assuming the parents have shared custody. It is also common for parents to find new partners after the divorce, which creates confounders when trying to collect the correct parental support. For example, the first born might only experience support from two biological parents, but the later born might experience support from both the biological and

the two new parents. This means that siblings with the same parents can receive widely different parental support, which creates a confounder for birth order.

This leads us into an interesting debate were birth order perhaps no longer is a reliable variable in social science today, since the traditional conjugal family might not exist in the same extent. This since many individuals has both biological siblings and non-biological siblings from their parent’s new partners. The problem here is that this creates confounders for the birth order variable. It is hard to distinguish where you should draw the line of what a sibling really is; especially in social sciences were interaction between individuals often is key. Should it be drawn strictly at biological siblings, or should it include all individuals living under the same roof with the same parents? This is a problem that birth order today struggles with more than ever, and also leads us closer to the real question – should we even consider birth order as a relevant variable? Birth order has in recent years struggled to produce significant empirical result in different fields of social science; an example of this is in personality (Rohrer et al., 2015).

As discussed in the beginning this study, birth order is often used in western popular culture as an easy explanation to a complex problem – how we obtain our personality and our individual traits. In that type of literature, birth orders effect on our personal traits is more or less considered as a fact. But more and more research speak against this notion. In conclusion, our research puts some doubts on, and provides some careful considerations towards working with birth order as a variable in social science.

This study had some limitations, and one of the main concerns was our sample. Since our results were based on a convenience sample, we were not able to generalize our findings and make predictions about the entire population of young adults - but merely young adults attending a university in Sweden. A bigger sample would have contributed to the statistical power needed for our sample, making it possible for us to find actual effects. Our low number

of participants could also have caused a type I error in our results, where we possibly infer the existence of an effect that is not actually there. This could partly explain why we found a difference in gender amongst young adults which earlier research had not found.

Another limitation with this study was the confounders for our birth order variable. For example, when asking for specific birth position we did not specify that we meant that they should answer regarding their biological siblings, nor did we give an option to those who had non-biological siblings.

Furthermore, since we collected the data through an online questionnaire, we were unable to ensure that only young adults between the ages of 18 and 25 participated in our questionnaire, meaning that we had low control over the collection of our data. Moreover, we could not make any casual inferences regarding birth order and gender on non-suicidal self-injury and perceived parental support, due to the retrospective construction of some of the questions and statements in our questionnaire. The retrospective aspect of our study might have influenced the results, and therefore it is important to bring the aspect of time to light as a possible contributing factor.

Despite these limitations, this study also has its strengths. To avoid any possible measurement errors, we used already established measuring instruments, and thereby we ensured both the validity and reliability of our study. Even though The Social Provisions scale was altered slightly from the original, with the exclusion of two provisions, this should not interfere with the final results. The construction of this scale was strength in our study as it included negative items. By including negative items, we reduced the possibility of

acquiescence bias (Baumgartner & Steenkamp, 2001). More specifically, these negative items enabled us to detect if a participant had agreed with questions or statements in our survey without regard for the actual content of the question or statement.

enabled us to facilitate the data collection during a short period of time, and in a cost effective manner. Moreover, it allowed us to get a large number of participants (N = 202).

It appears that non-suicidal self-injury has not been studied widely across a longer period of time. On close review of earlier research, we propose future research to approach non-suicidal self-injury with a longitudinal research design, where the same participants are followed from adolescence to young adulthood. The reasoning behind this being that earlier research has suggested that non-suicidal self-injury decreases from adolescence to young adulthood (García-Nieto et al., 2014; Jacobson & Gould, 2007), which was contradicted by our results. It would be of relevance for future research to use this research design to follow the same participants with the purpose of understanding if non-suicidal self-injury either decreases or continues being stable over time. Besides suggesting a longitudinal research design to understand the development of non-suicidal self-injury over time, we propose a qualitative research design to understand why, and to thereby deepen the understanding of non-suicidal self-injury over time.

To summarize, this study contributes to a greater knowledge of the non-suicidal self-injury. As stated by previous research, non-suicidal self-injury is a growing public health problem (Nock & Prinstein, 2004), and it stands in need for future research (American Psychiatric Association, 2013). To the best of our knowledge, this study is the first study examining the effect of birth order on non-suicidal self-injury among young adults. Therefore, it does not replicate already existing studies, but reveals new insights in the field.

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Appendix 1.

The Effect of Birth Order on Self-Injury for Young Adults

The purpose of this survey is to study the effect of birth order between perceived parental support and non-suicidal self-injury. This study will be conducted on young adults (18-25), so if you are younger than 18 or older than 25 you cannot participate.

Your participation in this survey is completely voluntary and on your own terms, meaning that you can end your participation whenever you want. Your answers will be treated with the utmost confidentiality and only authorized people will take part of your answers. The data that emerges from this study will only be used for scientific purposes and always be presented on a group level.

This survey will take about 5 minutes to complete.

If you have any questions concerning this survey, feel free to contact Delila Kadric or Ludvig Löfquist on selfinjurysurvey@hotmail.com

If you feel depressed and/or practice self-injury, you can either contact a health care central or call 1177 to get medical information. If you have suicidal thoughts you can call 112 or contact a psychiatric emergency clinic.

How old are you? (If you're younger than 18 or older than 25 you can close down this survey).

□

18

□

19

□

20

□

21

□

22

□

23

□

24

□

25

Which gender do you identify yourself as?

□

Male

□

Female

□

Other Birth Order

This section will ask for whether you have siblings and if so whether you are the oldest-, middle-, or youngest child in the family. For example if you have three older brothers and one younger sister, you are a middle child.

Describe your birth order position amongst your siblings.

□

I do not have any siblings

□

I am the oldest child

□

I am the middle child

□

I am the youngest child

Appendix 2.

Perceived Parental Support

Answer the following statements with your own perception in mind. If you perceive two different types of support from each of your parents, you answer accordingly to the parent you have received the most support from.

I can depend on my parents to help me if I really need it. Strongly disagree

□ □ □ □

Strongly agree

I feel that I do not have a close personal relationship with my parents. Strongly disagree

□ □ □ □

Strongly agree

I cannot turn to my parents for guidance in times of stress. Strongly disagree

□ □ □ □

Strongly agree My parents do not view me as competent.

Strongly disagree

□ □ □ □

Strongly agree I do not think that my parents respect my skills and abilities. Strongly disagree

□ □ □ □

Strongly agree

If something went wrong, my parents would not come to my assistance. Strongly disagree

□ □ □ □

Strongly agree

I have a close relationship with my parents, that provides me with a sense of emotional security and well-being.

Strongly disagree

□ □ □ □

Strongly agree I can talk to my parents about important decisions in my life. Strongly disagree

□ □ □ □

Strongly agree My parents recognize my competence and skills.

Strongly disagree

□ □ □ □

Strongly agree

My parents are trustworthy people that I could turn to for advice if I was having problems.

Strongly disagree

□ □ □ □

Strongly agree I feel a strong emotional bond with my parents.

I cannot depend on my parents for aid if I really need it. Strongly disagree

□ □ □ □

Strongly agree

I do not feel comfortable talking about my problems with my parents. Strongly disagree

□ □ □ □

Strongly agree

My parents admire my talents and abilities.

Strongly disagree

□ □ □ □

Strongly agree I lack a feeling of intimacy with my parents.

Strongly disagree

□ □ □ □

Strongly agree I can count on my parents in an emergency.

Appendix 3.

Non-Suicidal Self-Injury

How many times, during the last six months, have you purposely done any of the following to yourself?

0 1 2 3 4 5 6 Never One time Two times Three times Four Times Five times More than five times ____ Cutting wrists, arms, or body areas

____ Burning with cigarette, lighter, or match ____ Carving words, pictures, etc. into skin ____ Severe scratching, causing bleeding ____ Biting self, so that the skin is broken ____ Sticking sharp objects into the skin ____ Banging head, thereby causing a bruise ____ Punching self, thereby causing a bruise ____ Preventing wounds from healing

____ Any self-harm severe enough to require hospitalization/medical treatment Have you ever during your lifetime purposely done any of the examples above?

□

Yes

□

No

If you, during your lifetime, performed self-injury - did you feel that you had supportive parents during that time?

□

Yes

□

No

□

I have never performed self-injury