Are qualitative and quantitative sleep problems associated with delinquency when controlling for psychopathic features and parental supervision?

Transcription

1 J Sleep Res. (2015) 24, Sleep and delinquency Are qualitative and quantitative sleep problems associated with delinquency when controlling for psychopathic features and parental supervision? HEIDI BACKMAN 1, TAINA LAAJASALO 1,2, SUVI SAUKKONEN 3, VENLA SALMI 4, JANNE KIVIVUORI 4 and EEVA T. ARONEN 3 1 Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland; 2 Department of Child Psychiatry, Forensic Psychiatric Center for Children and Adolescents, Children s Hospital, Helsinki University Central Hospital, Helsinki, Finland; 3 University of Helsinki and Helsinki University Central Hospital/Child Psychiatry, Helsinki, Finland; and 4 Criminological Unit, National Research Institute of Legal Policy, Helsinki, Finland Keywords adolescence, psychopathy, sleep quality, sleep quantity, violence Correspondence Heidi Backman, MA, Institute of Behavioural Sciences, University of Helsinki, PO Box 9, FI Helsinki, Finland. Tel.: ; heidi.backman@alumni.helsinki.fi Accepted in revised form 26 February 2015; received 28 October 2014 DOI: /jsr SUMMARY The aim of this study was to explore the relationship between sleep, including both qualitative and quantitative aspects, and delinquent behaviour while controlling for psychopathic features of adolescents and parental supervision at bedtime. We analysed data from a nationally representative sample of 4855 Finnish adolescents (mean age 15.3 years, 51% females). Sleep problems, hours of sleep and delinquency were evaluated via self-report. Psychopathic features were measured with the Antisocial Process Screening Device Self-Report. In negative binomial regressions, gender and sleep-related variables acted as predictors for both property and violent crime after controlling for psychopathic features and parental supervision at bedtime. The results suggest that both sleep problems (at least three times per week, at least for a year) and an insufficient amount of sleep (less than 7 h) are associated with property crime and violent behaviour, and the relationship is not explained by gender, degree of parental supervision at bedtime or co-occurring psychopathic features. These results suggest that sleep difficulties and insufficient amount of sleep are associated with delinquent behaviour in adolescents. The significance of addressing sleep-related problems, both qualitative and quantitative, among adolescents is thus highlighted. Implications for a prevention technique of delinquent behaviour are discussed. INTRODUCTION Adolescents tend to sleep too little and have a rising number of sleep problems (Gradisar et al., 2011; National Sleep Foundation, 2013; Singh and Kenney, 2013). Sleep problems were long seen as a consequence rather than a cause of delinquent lifestyle (Clinkinbeard et al., 2011). Only recently, researchers interested in factors influencing adolescent delinquency have considered altered sleep as a potential biological risk factor for criminal acts. Interest was sparked by studies showing that sleep loss is related to diminished behavioural response inhibition, increased irritability and hostility and negative affective states which, in turn, are related to aggression and violence (Ireland and Culpin, 2006). Several recent large epidemiological studies have found a link between adolescent delinquency and sleep problems (Catrett and Gaultney, 2009), insufficient sleep amount (Clinkinbeard et al., 2011; Hildenbrand et al., 2013; Meldrum et al., 2015; Peach and Gaultney, 2013) or both (Meijer et al., 2010). However, unanswered questions remain. Associations between sleep and different crime types have seldom been evaluated, although one study reported that the link between sleep deprivation and property crime is stronger than that between sleep loss and violent crime (Clinkinbeard et al., 2011). Further, assessment of the impact of qualitative sleep problems on delinquency and its subtypes has been neglected. As self-reported sleep problems are not necessarily related to self-reported sleep 543

2 544 H. Backman et al. amount (Meijer et al., 2010), addressing both quality and quantity aspects of sleep is important (Lund et al., 2010). Finally, there might be a third factor that underlies both sleep problems and delinquent behaviour (van Nieuwenhuijzen et al., 2009), e.g. impulsivity (Clinkinbeard et al., 2011), or diminished self-control (Meldrum et al., 2015). Also, a possible association between altered sleep and psychopathic features has been proposed in the literature (Hare, 1970), but empirical studies are almost non-existent. Psychopathy is a personality disorder characterized by affective, interpersonal, behavioural and antisocial features, such as callousness, shallow emotions, lack of empathy, manipulativeness, impulsivity and persistent violation of social norms (Blair, 2013). According to a large-scale metaanalysis by Asscher et al. (2011), a link between adolescent delinquency and psychopathic features has been found consistently. A distinction often used in criminological studies divides crime into two categories: expressive (violent crime) and instrumental (property crime). Although adolescent offenders with psychopathic features commit both types of crime, psychopathy seems to be more related to instrumental violence (Flight and Forth, 2007). The importance of parental control has been highlighted in the studies investigating sleep and delinquency (Catrett and Gaultney, 2009; Clinkinbeard et al., 2011; Meldrum et al., 2015). Adolescents who report parental supervision go to bed earlier and have more sleep than those without a set bedtime (Adam et al., 2007). Poor parental supervision at bedtime is known to be associated with delinquency (Clinkinbeard et al., 2011). The aim of this study was to explore the relationship between qualitative and quantitative aspects of sleep and delinquent behaviour among Finnish adolescents. We also explored whether the relationship differed between the crime types (property versus violence). The second aim of the study was to investigate the role of psychopathic features for the associations between sleep and delinquent behaviour. Based on our previous results (Aronen, E. T., Laajasalo, T., Backman, H., Saukkonen, S., Salmi, V., Jokela, M. and Kivivuori, J., unpublished data) and earlier literature in adults (Hare, 1970; Meldrum et al., 2015), we hypothesized that controlling for psychopathic features would diminish the size of the effect between sleep and delinquent behaviour. Finally, we also controlled for parental supervision in all of the analyses, as it is a variable known to be linked positively to the amount of sleep among adolescents (Adam et al., 2007) and negatively to youth delinquency (Clinkinbeard et al., 2011). METHODS Participants The present study is part of the Finnish Self-Report Delinquency Study, a series of nationally representative self-report surveys of juvenile delinquency covering a wide variety of delinquent behaviours and a set of individual and family-level background factors. The survey was conducted in 51 municipal comprehensive schools in the spring of All ninth-grade pupils were asked to participate in the study and complete the study questionnaire. The response rate was 80%. The final sample consists of 4855 students [mean age 15.3 years, standard deviation (SD) = 0.55]. Of the sample, 50.9% were female and 49.1% male. The questionnaire was completed anonymously via computer during a regular class supervised by a trained teacher. Formal ethical approval of the parents was not required for this study, in accordance with regulations of the Finnish Advisory Board of Research Integrity. Details related to the survey procedure and the study sample can be found elsewhere (Laajasalo et al., 2014). Measures Sleep problems and sleep amount were assessed with four sleep questions reflecting qualitative and quantitative sleep problems; two of the questions indicated frequency and duration of sleep problems, the other two indicated sleep amount on school nights and weekend nights (see Appendix). The questions were modified from the Sleep Self-Report (Owens et al., 2000) and the Sleep Disturbance Scale for Children (Bruni et al., 1996). The items were rated on a Likert-type scale. Frequent and persistent sleep problems were indicated by a combination of two variables, i.e. adolescents reporting sleep problems at least three to five times per week and for more than 1 year. In a similar vein, an insufficient amount of sleep was indicated if a participant reported sleeping less than 7 h on both school and weekend nights. The 7-h cutoff point was chosen because a 7-h sleep amount is widely considered insufficient (National Sleep Foundation, 2013). Parallel values have also used in previous studies (Clinkinbeard et al., 2011; O Brien and Mindell, 2005). These two dichotomized sleep-related variables were used in statistical analysis to predict delinquent behaviour (see Appendix). For all offences, we requested that the respondent indicate the number of times engaging in the particular behaviour over the past 12 months. A scale measuring involvement in property offences was formed by adding up the number of the following six offences committed during the last year: graffiti, shoplifting, stealing from school, motor vehicle theft, other theft and breaking and entering. Correspondingly, the variable regarding involvement in violent offences was formed by adding up the number of the following offences reported by the respondent: fighting and beating up somebody. Additive indices based on self-report are used commonly in criminological research as a reflector of delinquent activity (Clinkinbeard et al., 2011; van Nieuwenhuijzen et al., 2009; Peach and Gaultney, 2013). In the statistical analysis, the greatest possible number of offences was set at 25 per person per item. The range of property offences was and of violent offences The means were 1.10

3 Sleep and delinquent behaviour 545 (SD = 8.37) for the number of property offences and 0.28 (SD = 3.26) for the number of violent offences. In the last 12 months, 59.1% of all participants had not engaged in any property crime, 87.2% had not engaged in any violent crime and 56.3% had not engaged in either crime. Psychopathy was measured via the Antisocial Personality Screening Device Self-Report (APSD-SR) (Frick and Hare, 2001), which consisted of 20 items scored on a three-point scale (0 = not at all true, 1 = sometimes true, 2 = definitely true). The sum of the items yields a total score for the APSD- SR that reflected psychopathic features in this study. The factorial validity of the instrument was described, and a threefactor model was found to best fit the data from Finnish adolescents; a more detailed description of the factor analyses is given elsewhere (Laajasalo et al., 2014). Parental supervision regarding sleep behaviours was measured with one statement: My parents supervise that I go to bed on time. Answers were given on a five-point Likert scale (from 1 = never to 5 = always). Statistical analysis The data were analysed using IBM SPSS statistics (version 21, SPSS Inc., Chicago, USA). Appropriate sample weights were used to ensure that the sample was representative of Finnish youth (Laajasalo et al., 2014). To determine whether sleep was associated with delinquency and psychopathy, bivariate correlations were performed between the dichotomized sleeprelated variables, delinquency and the APSD-SR total score. Furthermore, a series of negative binomial regression analyses were conducted to investigate the relationship between sleep and delinquency (property and violence), first controlling for parental supervision (initial models 1 and 3) and then also for psychopathic features (secondary models 2 and 4). Negative binomial analysis was an appropriate method, as variables reflecting property crime and violent crime (dependent variables) were not distributed normally and the variance was greater than the mean in both of the delinquency distributions. In the regression analyses, the target groups were sleep quality and quantity problems, as well as males. Accordingly, those adolescents who did not have sleep difficulties comprised the reference groups with females. RESULTS The bivariate correlations in Table 1 show positive relationships between sleep problems and property and violent delinquency and between insufficient amount of sleep and delinquency. Similarly, psychopathy was correlated positively with sleep problems, insufficient amount of sleep and both types of delinquency. Males were more likely than females to commit violent acts, as reflected by the stronger positive correlation in males than in females. Parental supervision was associated negatively with the sleep and crime variables as well as with psychopathic features, indicating that the more frequently parents controlled bedtimes, the less likely adolescents were to report having sleep problems, insufficient sleep amount, criminal acts and psychopathic features. Table 2 shows that sleep problems and an insufficient sleep amount were associated significantly with both property and violent crime. Despite the inclusion of psychopathy as a control variable (models 2 and 4), the association between sleep variables and delinquency remained significant. However, the size of the effects diminished slightly with both of the sleep variables after controlling for co-occurring psychopathic features. The only exception was insufficient sleep amount: the confidence intervals, counted by the standard errors of the regression coefficients, overlapped between models 1 and 2. Thus, there was no change in the effect size of quantitative sleep problems between the models investigating property crime. Both sleep quality and sleep quantity had stronger effects on violent crime than on property crime in all the models. In the models investigating violent crime (models 3 and 4), lack of sleep predicted violent crime more strongly than sleep problems. In fact, those sleeping less than 7 h on both school and weekend nights had times the probability of committing violent crimes than those sleeping more than 7 h after controlling for parental supervision. In the models investigating property crime (models 1 and 2), the effect was also greater for insufficient sleep amount than for sleep problems. DISCUSSION In our large nationally representative sample of Finnish community youth, we found that sleep quality and quantity Table 1 Bivariate correlations of crime and sleep variables, gender, parental supervision parameter and psychopathic features as measured by the Antisocial Personality Screening Device Self-Report Variable Property crime 2 Violence crime 0.35** 3 Gender (male) ** 4 Qualitative sleep problems 0.12** 0.07** 0.04** 5 Insufficient sleep amount 0.11** 0.11** 0.06** 0.12** 6 Psychopathic features 0.39** 0.26** 0.21** 0.11** 0.10** 7 Parental supervision at bedtime 0.17** 0.13** 0.04* 0.06** 0.07** 0.17** *P < 0.05; **P < 0.01.

4 546 H. Backman et al. Table 2 Regression coefficients of gender, sleep variables and parental supervision parameter for models 1 2 (property crime) and models 3 4 (violent crime). Psychopathic features as measured by the Antisocial Personality Screening Device Self-Report (APSD-SR) were added in models 2 and 4 Property crime Violent crime Model 1 Model 2 Model 3 Model 4 Variable b (SE) Exp (B) b (SE) Exp (B) b (SE) Exp (B) b (SE) Exp (B) Gender (male) 1.07*** (0.04) *** (0.05) *** (0.10) *** (0.11) 9.47 Qualitative sleep problems 1.60*** (0.07) *** (0.08) *** (0.10) *** (0.11) 4.45 Insufficient sleep amount 1.77*** (0.09) *** (0.09) *** (0.12) *** (0.12) 5.45 Control variables Parental supervision 0.25*** (0.02) *** (0.02) *** (0.03) *** (0.01) 0.76 Psychopathic features 0.15*** (0.00) *** (0.03) 1.12 The b value indicates how strongly independent variables influence dependent variables. Exp (B) = factor change in odds for unit increase in variable. Sleep problems at least three times per week for at least 1 year. Less than 7 h of sleep on both school and weekend nights. Total APSD-SR score. ***P < problems were associated significantly with delinquency even after controlling for psychopathic features and parental supervision at bedtime. The present study is the first to control for both parental supervision at bedtime and the psychopathic features of the adolescents while studying the associations between sleep and delinquent behaviour. Moreover, we measured both sleep problems (qualitative and quantitative) and delinquency (property and violent) in more detail than have the majority of previous studies on this subject. Our findings are novel in reporting that psychopathic features do not explain the association between sleep and delinquency, and the results strongly support the findings of earlier studies reporting a relationship between sleep problems and delinquency. We also found that sleep was associated significantly with both property crime and violent behaviour. However, unlike in a previous study (Clinkinbeard et al., 2011), the association between sleep and delinquency was stronger for violent crimes than for property offences. Reasons for the discrepant findings between these two studies might lie in the operationalization of the variables. Regarding crime variables, the number and content of the variables differed. For example, unlike in the Clinkinbeard et al. (2011) study, we did not include property damage in our property delinquency sum variable, and weapons were not mentioned in the items measuring violent crimes. Further, in terms of sleep variables, we measured both qualitative and quantitative sleep difficulties, whereas Clinkinbeard et al. (2011) assessed sleep with only one question (typical hours of sleep). Moreover, we defined lack of sleep as sleeping less than 7 h on both weekend and weekday nights, reflecting severe sleep deprivation. Clinkinbeard et al. (2011) hypothesized that to induce violent crime sleep deprivation would have to be severe, whereas even milder deprivation would be sufficient to cause distorted perceptions, such as a need for immediate gratification, which is related to property crimes. In another study, the impact of sleep loss on functioning was the greatest among those who were sleep-deprived on both weekday and weekend nights (Roberts et al., 2009). Thus, the strong association between violent crimes and sleep loss might reflect the more severe and persistent nature of sleep deprivation among individuals in our sample relative to Clinkinbeard et al. (2011). Although the relationship between poor sleep and violence is widely known (Kamphuis et al., 2012), in this study there might have been a third, unknown risk factor that strengthened the relationship between sleep problems and violent behaviour more than the relationship between poor sleep and property crime. It is also worth noting that our qualitative sleep variable, which reflected severe sleep problems, was also related more strongly to violent crimes than to property offences. Future research should include complex measures of sleep, investigating in more detail the role of severity of various sleep problems in property versus violent crimes. Our results suggest that sleep is associated with delinquency independently of parental supervision at bedtime. However, we still found a negative correlation between the frequency of parental supervision and sleep problems and criminal acts as well as psychopathic features, which indicates that parental supervision might have a role when examining the inter-relationships between these variables. One reason why parental supervision at bedtime did not have a significant effect in our analysis might lie in the operationalization of the parental supervision. We focused narrowly on the effect of supervising bedtimes, whereas other studies concerning delinquency have used more elaborate measures of parental controlling behaviours (Bowman et al., 2007; Clinkinbeard et al., 2011). Specifically, parentally set bed-

5 Sleep and delinquent behaviour 547 times do not necessarily determine the time adolescents fall asleep, as they may remain awake in bed. Interestingly, psychopathic features did not have a significant role in the association between sleep and delinquency, contrary to our hypothesis. However, most of the effect sizes diminished slightly after controlling for psychopathic features. It might be fruitful to investigate the subfactors of psychopathy in the models assessing the relationships between sleep, psychopathy and delinquency. There are indications that the relationship differs between various facets and delinquency (Blair, 2013). Further, the role of other variables that overlap partly with psychopathy warrant more study. For example, low self-control has been known to be linked to psychopathy (Wiebe, 2003), and according to the study by Meldrum et al. (2015), self-control mediates the relationship between sleep and delinquency. In a similar vein, impulse control might play a crucial role (Peach and Gaultney 2013). Several limitations must be addressed. First, the crosssectional study design does not allow for causality inferences. We used the APSD-SR total score as a measure of psychopathy. In future, the relationships between sleep and different types of delinquent acts and different facets of psychopathy construct need to be studied. Also, as in other large community studies, we had to rely solely upon selfreports when measuring sleep and psychopathy. However, research has demonstrated sufficient agreement between self-reported sleep characteristics and objective measures (Lockley et al., 1999), as well as between the APSD-SR and scores obtained from other informants (Meyer et al., 2001). Finally, despite the fact that our sleep-related variables were derived from a previous measure, a major problem plaguing adolescent sleep research in general is the lack of precise definition and standardized measures of sleep problems (Shochat et al., 2014). This study shows that sleep quality and quantity is associated with delinquency in adolescents regardless of their psychopathic personality features or parental supervision at bedtime. Although the relationships between sleep, psychopathy and delinquency are likely to be multidimensional and complex, these findings suggest that a sleepdeprived adolescent, even without psychopathic features, might be at risk of acting violently or committing property crimes. Therefore, education for adolescents, parents and teachers regarding consequences of sleep loss as well as screening for sleep disturbances and offering interventions to improve sleep at school health settings is important, as are studies to assess the impact of such interventions on delinquency in adolescents. Also, parental supervision at bedtime should be taken into account. Further, as policies such as delayed school start times seem to be efficient in increasing the sleep amount obtained by youth (Boergers et al., 2014), they may also serve as a prevention technique of delinquent behaviour. Finally, more attention should be paid to sleep as a part of interventions that focus upon youth who are involved in the juvenile justice system. In future studies, both the quality and quantity aspects of sleep as well as the subtypes of criminal acts must be considered. Regarding potential covariates, the subfactors of psychopathy and their relation to both sleep and delinquency need to be examined. ACKNOWLEDGEMENTS A special thank you for Liisa Tulensalo for help with finalizing the manuscript. This study was supported by Helsinki University Central Hospital Research Grants (EVO) TYH and In addition, the authors would like to thank the Editors and the Reviewers for their constructive and useful comments and suggestions, which greatly improved the paper. AUTHOR CONTRIBUTIONS HB had a major role in planning and carrying out data analysis and interpreting the results. She was mainly responsible for the writing of the article. TL planned the study and participated in planning of data analysis, interpretation of results and writing the paper. SS participated in interpreting the results and revising the manuscript. VS and JK planned and organized data collection and participated in revising the manuscript. EA planned the study and participated in planning of data analysis, interpretation of results and revising the manuscript. CONFLICT OF INTEREST No conflicts of interest declared. REFERENCES Adam, E. K., Snell, E. K. and Pendry, P. Sleep timing and quantity in ecological and family context: a nationally representative timediary study. J. Fam. Psychol., 2007, 21: Asscher, J., van Vugt, E., Stams, G. J. et al. The relationship between juvenile psychopathic traits, delinquency and (violent) recidivism: a meta-analysis. J. Child Psychol. Psychiatry, 2011, 52: Blair, R. J. The neurobiology of psychopathic traits in youths. Nat. Rev. Neurosci., 2013, 14: Boergers, J., Gable, C. J. and Owens, J. A. Later school start time is associated with improved sleep and daytime functioning in adolescents. J. Dev. Behav. Pediatr., 2014, 35: Bowman, M. A., Prelow, H. M. and Weaver, S. R. Parenting behaviors, association with deviant peers, and delinquency in African American adolescents: a mediated-moderation model. J. Youth Adolesc., 2007, 36: Bruni, O., Ottaviano, S., Guidetti, V. et al. The Sleep Disturbance Scale for Children (SDSC). Construction and validation of an instrument to evaluate sleep disturbances in childhood and adolescence. J. Sleep Res., 1996, 5: Catrett, C. D. and Gaultney, J. F. Possible insomnia predicts some risky behaviors among adolescents when controlling for depressive symptoms. J. Genet. Psychol., 2009, 170: Clinkinbeard, S. S., Simi, P., Evans, M. K. and Anderson, A. L. Sleep and delinquency: does the amount of sleep matter? J. Youth Adolesc., 2011, 40:

6 548 H. Backman et al. Flight, J. I. and Forth, A. E. Instrumentally violent youths. The roles of psychopathic traits, empathy, and attachment. Crim. Justice Behav., 2007, 34: Frick, P. J. and Hare, R. D. The Antisocial Process Screening Device. Multi-Health Systems, Toronto, ON, Gradisar, M., Gardner, G. and Dohnt, H. Recent worldwide sleep patterns and problems during adolescence: a review and metaanalysis of age, region, and sleep. Sleep Med., 2011, 12: Hare, R. D. Psychopathy: Theory and Research. Wiley, New York, NY, Hildenbrand, A. K., Daly, B. P., Nicholls, E. et al. Increased risk for school violence-related behaviors among adolescents with insufficient sleep. J. Sch. Health, 2013, 83: Ireland, J. L. and Culpin, V. The relationship between sleeping problems and aggression, anger, and impulsivity in a population of juvenile and young offenders. J. Adolesc. Health, 2006, 38: Kamphuis, J., Meerlo, P., Koolhaas, J. P. and Lancel, M. Poor sleep as a potential causal factor in aggression and violence. Sleep Med., 2012, 13: Laajasalo, T., Saukkonen, S., Kivivuori, J., et al. Brief report: Selfreported psychopathic-like features among Finnish community youth: Investigation of the factor structure of the antisocial personality screening device. J. Adolesc., 2014, 37: Lockley, S. W., Skene, D. J. and Arendt, J. Comparison between subjective and actigraphic measurement of sleep and sleep rhythms. J. Sleep Res., 1999, 8: Lund, H. G., Reider, B. D., Whiting, A. B. and Prichard, J. R. Sleep patterns and predictors of disturbed sleep in a large population of college students. J. Adolesc. Health, 2010, 46: Meijer, A. M., Reitz, E., Dekovic, M. et al. Longitudinal relations between sleep quality, time in bed and adolescent problem behaviour. J. Child Psychol. Psychiatry, 2010, 51: Meldrum, R. C., Barnes, J. C. and Hay, C. Sleep deprivation, low selfcontrol, and delinquency: a test of the strength model of selfcontrol. J. Youth Adolesc., 2015, 44: doi: / s Meyer, G. J., Finn, S. E., Eyde, L. D. et al. Psychological testing and psychological assessment: a review of evidence and issues. Am. Psychol., 2001, 56: National Sleep Foundation. Teens and Sleep, Available from (accessed 14 January 2015). van Nieuwenhuijzen, M., Junger, M., Velderman, M. K. et al. Clustering of health-compromising behavior and delinquency in adolescents and adults in the Dutch population. Prev. Med., 2009, 48: O Brien, E. M. and Mindell, J. A. Sleep and risk-taking behavior in adolescents. Behav Sleep Med., 2005, 3: Owens, J. A., Maxim, R., Nobile, C. et al. Parental and self-report of sleep in children with attention-deficit/hyperactivity disorder. Arch. Pediatr. Adolesc. Med., 2000, 154: Peach, H. D. and Gaultney, J. F. Sleep, impulse control, and sensation-seeking predict delinquent behavior in adolescents, emerging adults, and adults. J. Adolesc. Health, 2013, 53: Roberts, R. E., Roberts, C. R. and Duong, H. T. Sleepless in adolescence: prospective data on sleep deprivation, health and functioning. J. Adolesc., 2009, 32: Shochat, T., Cohen-Zion, M. and Tzischinsky, O. Functional consequences of inadequate sleep in adolescents: a systematic review. Sleep Med. Rev., 2014, 18: Singh, G. K. and Kenney, M. K. Rising prevalence and neighborhood, social, and behavioral determinants of sleep problems in US children and adolescents, Sleep Disord., 2013, doi: /2013/ Wiebe, R. P. Reconciling psychopathy and low self-control. Justice Q., 2003, 20: APPENDIX: SLEEP ITEMS (1 4) OF THE FINNISH SELF-REPORT DELINQUENCY STUDY (FSRD- 12) AND COMBINATIONS OF THE ORIGINAL ITEMS (5 6) (1) Do you think you have trouble sleeping? 1 No sleep problems 2 Less than once a week nights a week nights a week 5 Every or almost every night (2) If you do, how long have you had trouble sleeping? 1 No sleep problems 2 Less than 4 weeks months months years 6 More than 2 years (3) How many hours of sleep do you get on school nights? Less than 5 (4) How many hours of sleep do you get on weekend nights? Less than 5 (5) Adolescent reports having trouble sleeping three to five times per week for 1 or more years 1 No 2 Yes (6) Adolescent reports sleeping less than 7 h on school and weekend nights 1 No 2 Yes