Cannabis use and violence in three remote Aboriginal Australian communities: Analysis of clinic presentations

Abstract

Anecdotal reports have linked cannabis use to violence in some remote Australian Aboriginal communities. We examine the relationship between cannabis use and presentations to local clinics for violence-related trauma at a population level. As part of a larger study, estimates of cannabis and alcohol use status were obtained for 264 randomly selected individuals aged 14–42. These estimates were collected from Aboriginal health workers and respected community informants using a previously validated approach. Clinic records for the sample were audited for physical trauma presentations between January 2004 and June 2006. One in 3 individuals (n = 88/264) presented to the clinic with physical trauma. Of these, the majority (65.9%, n = 58/88) had at least one presentation that was violence-related. Nearly 2 in every 3 of the total presentations for trauma following violence (n = 40/63) involved the use of a weapon. Hunting tools were most often used, followed by wooden or rock implements. Individuals who reported any current cannabis use were nearly 4 times more likely than nonusers to present at least once for violent trauma after adjusting for current alcohol use, age, and sex (OR = 3.8, 95% CI [1.5, 9.8]). Aboriginal individuals in these remote communities experience high rates of physical trauma and violence, often involving weapons. A comprehensive study is needed to explore the association between cannabis and violence. At the same time, an investment in local programmes is needed to address cannabis use and underlying risk factors for substance use and for violence.

Keywords

Australia cannabis Indigenous injury trauma violence

Introduction

Over recent years, there have been widespread anecdotal reports of violence related to high levels of cannabis use in some remote Aboriginal communities in northern Australia (Wild & Anderson, 2007). In some of these communities, access to alcohol is limited, and cannabis has had a rapidly growing profile as a drug of misuse (Clough, D’Abbs, et al., 2004; Lee, Conigrave, Patton, & Clough, 2009). The impact of cannabis use, including cannabis-related violence, on families and children has been noted in a government report on the safety of Aboriginal children (Wild & Anderson, 2007).

In the literature, violence is occasionally associated with cannabis-induced psychosis (Moss & Tarter, 1993) and has been observed with instances of paranoia accompanying cannabis intoxication (Hall, Degenhardt, & Lynskey, 2001). However, anecdotal reports from affected communities suggest that this violence occurs when the cannabis supply becomes limited (Select Committee on Substance Abuse in the Community, 2007). In general (non-Indigenous) populations, irritability and aggression have been described as part of a cannabis withdrawal syndrome (American Psychiatric Association, 2013; Budney & Hughes, 2006; Coffey et al., 2002; Copeland, Swift, & Rees, 2001; Crowley, Macdonald, Whitmore, & Mikulich, 1998; Swift, Hall, Didcott, & Reilly, 1998). However, there has been no published research demonstrating an association at a population level between actual physical violence and cannabis use status.

We set out to study the association between cannabis use status and community incidence of clinic presentations for violent physical trauma in three remote Aboriginal communities in northern Australia (Arnhem Land, Northern Territory, NT). These communities have a well-documented high prevalence of regular and heavy cannabis use (often ≥ 6 cones, daily; Lee, Clough, Jaragba, Conigrave, & Patton, 2008). They also have intermittent periods where cannabis supply is scarce due to police seizures or other external events. Access to alcohol is restricted in these communities, making it somewhat easier to examine any potential association between cannabis use and violence.

Methods

Overview

We examined the association between presentations for violent physical trauma (noted in medical records) and individuals’ status as a current cannabis user as reported by health workers and key community members (proxy respondents) in a random sample of 264 community members. Ethics approval for the study was provided by the Human Research Ethics Committee of Menzies School of Health Research and the Northern Territory Health Department.

Setting

Located in remote northern Australia (Arnhem Land, NT), the three Aboriginal communities and smaller single-family settlements involved in the study have a combined population of around 1,700. Situated near a mining town with 1,000 non-Indigenous residents, the communities maintain traditional ceremonies and other cultural practices. One Aboriginal language is spoken. English is a secondary language and skills in English vary. About 90% of adults smoke tobacco (Lee et al., 2008). Cannabis is commonly used by 70% of males and 20% of females (Lee, Conigrave, et al., 2009) and is typically blended with tobacco and smoked using a “bucket bong,” which is a homemade water pipe, thought to deliver high concentrations of cannabinoids (Clough, D’Abbs, et al., 2004). Alcohol restrictions are in place, and were further strengthened¹ in July 2005.

Sample

The current data were collected as part of a larger longitudinal study of substance use (2001–2006) (Clough, D’Abbs, et al., 2004; Clough et al., 2006; Lee, Clough, et al., 2009). A total of 264 people, aged 14–42 years (in 2006) were randomly selected from community rolls over the study periods in 2001 and 2004 (males: n = 139, 52.7% and females: n = 125, 47.3%; Lee, Clough, et al., 2009). Two sources of data were used for the current analysis. First, estimates of current cannabis and alcohol use status were collected by KL in 2006 for each individual in the random sample. This was done by interviewing six key informants (“proxy respondents”) in private meetings. The informants were two Aboriginal health workers and four respected community leaders. As previously described (Clough et al., 2002; Clough, Cairney, et al., 2004), each proxy respondent was presented with the list of the 264 community members, and was asked to nominate whether each individual (to their knowledge) currently was using cannabis, and whether that individual was a drinker (of any alcohol). The validity of this method of estimation in these small remote Aboriginal communities has been previously demonstrated (Clough et al., 2002; Clough, Cairney, et al., 2004). Secondly, clinic medical records of these same 264 individuals were audited for presentations that involved trauma experienced from January 2004 to June 2006. This time frame was dictated by the larger study from which these data were drawn. This audit was conducted in each of the four local clinics accessed by Aboriginal residents in the study communities. Any entries that mentioned clinic visits involving physical trauma (accidents, violence, fights) were transcribed verbatim by one of us (KL). Health clinics report that the population of the study communities remained relatively stable during this time.

Derived variables and analysis

Age of individuals in the random sample (14–42 years) was categorised as: 14–25, 26–35 or 36–42 years. Transcribed records of physical trauma incidents noted in an electronic spreadsheet file were reviewed by two of us (KL and KS). Each trauma presentation was categorised as either accidental (including: industrial, recreational, or motor vehicle) or violence-related (mention of deliberate violence, whether as a victim or perpetrator, or injury from having intervened in an altercation). The number of physical trauma presentations recorded for each person was categorised as: one, two, or three or more presentations (over the 2.5-year study period). In violence-related incidents, the use of a weapon was classified as involving a body part (e.g., hand or foot) but no weapon, or two categories of weapons: wooden or rock implements (wooden stick or branch, walking stick, chair, or rock), and implements commonly used in these communities for hunting (knife, metal or iron bar, spear, axe, machete, boomerang, nulla nulla, shovel, pitch fork, shanghai, or metal wire). Descriptive data analyses were performed using SPSS Version 20. The associations between presenting at least once for violent trauma and current cannabis use status, alcohol use status, age, and sex were examined using univariate and multivariate logistic regression.

Results

Incidence of violence and other physical trauma

One in three people in the random sample (n = 88/264) presented to the clinic with a violent or accidental trauma incident over the 2.5-year study period. In 2004, 36 people presented with a trauma incident, with 57 in 2005 (35%, n = 49), and 13 in the first 6 months of 2006 (data not shown).

Of the individuals who presented for trauma, the majority (6 in 10) presented with violence-related trauma (65.9%, n = 58/88; 34 male and 24 female; Table 1). Among those who presented for any trauma, males (n = 34/58, 58.6%) and younger people were more likely to present with violence-related injuries (n = 48/58, 82.8% aged 14–35 vs. n = 10/58, 17.2%, aged 36–42). Some individuals presented more than once for trauma (Table 2), so there were 63 presentations for trauma among the 58 individuals.

Table 1.

Prevalence of a clinic presentation for trauma between January 2004 and June 2006 in a random sample of 264 Aboriginal community members in Arnhem Land (Northern Territory, remote Australia).

	Any presentation for trauma						No presentation for trauma
	Violence		Accidents		Any trauma
	n	(%)	n	(%)	n	(%)	n	(%)
Sex
Female	24	(41.4)	9	(30.0)	33	(37.5)	92	(52.3)
Male	34	(58.6)	21	(70.0)	55	(62.5)	84	(47.7)
Persons	58	(100)	30	(10.00)	88	(100.0)	176	(100.0)
Age (median)	27		27		27		27
14–25	27	(46.6)	13	(43.3)	40	(45.4)	81	(46.0)
26–35	21	(36.2)	14	(46.7)	35	(39.8)	62	(35.2)
36–42	10	(17.2)	3	(10.0)	13	(14.8)	33	(18.8)
Current cannabis use ^†
Yes	48	(88.9)	23	(85.2)	71	(87.7)	100	(34.6)
No	6	(11.1)	4	(14.8)	10	(12.3)	53	(65.4)
Current alcohol use ^†
Yes	30	(55.6)	18	(66.7)	48	(59.3)	84	(54.9)
No	24	(44.4)	9	(33.3)	33	(40.7)	69	(45.1)

†

Use in the past 12 months, as reported by proxy respondents in 2006; 30 missing records.

Table 2.

Prevalence of a clinic presentation for trauma that involved a weapon* between January 2004 and June 2006 among 63 trauma-related presentations in Arnhem Land (Northern Territory, remote Australia).

			A weapon or object used
	No weapon used		Wood or rock		Hunting tool
	n	(%)	n	(%)	n	(%)
Sex
Female	11	(47.8)	7	(58.3)	7	(25.0)
Male	12	(52.2)	5	(41.7)	21	(75.0)
Persons	23	(100.0)	12	(100.0)	28	(100.0)
Age
14–25	10	(43.5)	5	(41.7)	14	(50.0)
26–35	8	(34.8)	6	(50.0)	10	(35.7)
36–42	5	(21.7)	1	(8.3)	4	(14.3)
Total	23	(100.0)	12	(100.0)	28	(100.0)

Some subjects had more than one recorded incident of violence that involved a weapon; thus, total number of incidents (n = 63) is greater than the total number of subjects with a recorded incident of violence (n = 58).

Nearly 2 in every 3 incidents of violence involved the use of a weapon (63.4%, n = 40/63). Hunting implements were most often used (44.4% of violence-related presentations, n = 28/63), followed by wooden or rock implements (19.0%, n = 12/63; Table 2).

Overall, violence-related trauma was recorded for 1 in every 5 people in the random sample (n = 58/264, 21.9%; 34 males, 24 females).

Cannabis use and violence-related trauma

Just under two thirds of the randomly selected sample were current cannabis users (n = 171/264, 64.8%) according to proxy respondents. The youngest of these was 15 years old (range: 15–42 years).

Of the individuals who presented as a result of violence-related trauma, nearly 9 in 10 were current cannabis users (n = 48/54 cannabis users; four missing records; p = .001). Current cannabis users were nearly 4 times more likely to present for violence-related trauma compared with nonusers, after adjusting for age, sex, and current alcohol use (OR: 3.8, 1.5–9.8; Table 3). Cannabis users were also more likely than noncannabis users to have been injured by a weapon (wood, rock, or hunting tool: n = 36/38, 94.7%; numbers insufficient to test significance; data not shown).

Table 3.

Association between cannabis use* and at least one presentation for violent trauma between January 2004 and June 2006 in a random sample of 264 Aboriginal community members in Arnhem Land (Northern Territory, remote Australia).

	Number of subjects	Unadjusted odds ratio (95% CI)	Adjusted odds ratio (95% CI)^‡
Male (reference category = female)^¶	139 125	1.0 [0.9, 1.0]	1.1 [0.6, 2.3]
Age (continuous variable)	264	1.0 [0.9, 1.0]	1.0 [0.9, 1.1]
Current cannabis use^* ^†	234	3.7 [1.5, 9.2]^§	3.8 [1.5, 9.8]^§
Current alcohol use^* ^†	234	0.9 [0.5, 1.8]	0.8 [0.4, 1.5]

Cannabis and alcohol use in the past 12 months were estimated by proxy respondents in 2006.

†

30 subjects had missing records for cannabis and alcohol use status.

‡

Adjusted for sex, age, and current alcohol use.

Odds ratios where 1.0 is excluded.

Male is the category of interest (i.e., where male = 1) and is compared with the reference category of female (i.e., where female = 0).

Discussion

Individuals who were identified as current cannabis users were nearly 4 times more likely to present to a clinic for treatment of violence-related trauma than nonusers after adjusting for age, sex, and current alcohol use status (OR 3.8, 95% CI [1.5, 9.8]). To our knowledge this is the first scientific study worldwide to report an independent association between incidence of trauma and cannabis use status at a population (or health care facility) level.

The high prevalence and quantity of cannabis use observed in this population has been previously reported (Lee, Clough, et al., 2009). Also, community members and key agencies consistently report that violence is observed when there is a community-wide lack of cannabis supply (personal communications with KL and KC). An earlier government report also noted this phenomenon of violence when cannabis supply is limited (as opposed to when people are intoxicated) in northern Australia (Wild & Anderson, 2007). These communities may be vulnerable to violence because of a range of historical and social stressors (Select Committee on Substance Abuse in the Community, 2007). However similar associations between lack of cannabis supply and legal presentations resulting from violence have been anecdotally reported in vulnerable urban general populations in Australia (personal communications with health professionals).

There are a number of potential explanations for this association between cannabis use and violent trauma presentations. Trauma may be more common among cannabis users at the time of intoxication due to, for example, impaired attention and concentration (Crean, Crane, & Mason, 2011), impaired motor coordination and executive functioning, and a distorted sense of time and space (Lee et al., 2012); and intoxicated individuals may be more vulnerable to being targeted for violent assault and less able to avoid injuries or defuse conflict. Or those individuals who use cannabis may be more likely to be risk takers, which predisposes them to both cannabis use and to injury. However, the repeated occurrences, reported by community members and key agencies, of violence when cannabis supply runs out does not fit well with either explanation. Alternatively, those individuals who have a predisposition toward violence (e.g., because of a mental health disorder) may use cannabis as self-medication. However, evidence supporting a self-medication hypothesis from other studies is not compelling (Hall et al., 2001; Patton et al., 2002), and we are unable to test this with the cross-sectional data available in this present study. It is also possible that conflict arises from a strong desire for a resource that is not available in a community with many other pressures and stresses. In this context, it is worth considering the role of social and financial pressures in a setting where dealers make considerable profits, with cannabis selling at $100.00 per 2 x 4 cm bag (personal communications with KL and KC), which is approximately 5 times the price that would be charged in a major Australian urban setting. While violence can be associated with psychosis precipitated or exacerbated by cannabis, clinicians in these communities advise us that numbers of psychotic individuals are small, and these individuals are rarely violent (personal communications with KL).

It was not within the scope of this study to determine whether cannabis withdrawal was a contributing factor to incidents of violent trauma. However, community members report that many regular cannabis users become irritable and aggressive (against other people or property) for several days when cannabis supply runs out (e.g., after a police seizure). The levels of cannabis used in these communities are sufficient to account for both dependence and withdrawal, with typically six cones smoked daily using a bucket bong (Lee, Clough, et al., 2009; Lee et al., 2008), which is believed to be a very effective delivery device (Clough, D’Abbs, et al., 2004). Also, up to 90% of current cannabis users in this sample reported symptoms of dependence such as: craving, tolerance, and continued use despite obvious harm, and up to 30% reported symptoms such as: insomnia and headaches consistent with withdrawal (unpublished data, sample of n = 54 users). The duration of such symptoms (up to a week; Lee, Clough, et al., 2009) was also consistent with cannabis withdrawal. However, further research on the cause of the association is needed.

Severity of violence reported in this study

Of the 63 presentations for violent trauma, 60% involved the use of a weapon (wood, rock, or hunting tool). In particular, hunting tools were reported in just under half of these incidents. Both the implement used and the need to come to a clinic for treatment, indicate the serious nature of trauma. The prevalence of violence in these clinic charts is consistent with concerns expressed about violence by community leaders and policy-makers (Lee, Conigrave, et al., 2009; Ministerial Council on Drug Strategy, 2006; Wild & Anderson, 2007).

The incidence and severity of violence observed in this study is of major concern. More than 1 in every 5 people in this community sample presented at least once with trauma as a result of deliberate violence over this 2.5-year period. This equates to an estimated 8,788 individuals per 100,000 people per year, which is nearly 3 times the annual prevalence of violence-related trauma self-reported in national Australian surveys (3,012 per 100,000 general population; aged 18–44; Australian Bureau of Statistics, 2005), and much higher than the rate found in NT household surveys (4,942 victims per 100,000, in the past year; Australian Bureau of Statistics, 2008).

Cannabis in the context of other substance use and mental health issues

In these study communities where there are strict alcohol restrictions in place, cannabis has become the most common drug of misuse (Lee, Clough, et al., 2009). A tighter and locally developed alcohol management system was introduced halfway through the data collection period (in mid 2005). This greatly reduced the availability of alcohol (data not shown to protect the confidentiality of study communities). The possible substitution of cannabis for alcohol reinforces the need to address underlying social determinants of substance misuse such as unemployment, overcrowded housing, poor education, and lack of employment opportunities (Ministerial Council on Drug Strategy, 2006). While psychological after-effects of trauma may predispose individuals to substance misuse (Hunter, 1998), we do not have rigorous clinical or research data on the long-term impact of psychological or physical violence in Aboriginal communities in Australia. There are also transgenerational effects of other forms of substance use that should be considered, for example occurrence of fetal alcohol spectrum disorders (FASD) in a setting with previously heavy consumption of alcohol could potentially increase risk of aggression and of substance use in adult life (House of Representatives Standing Committee on Social Policy and Legal Affairs, 2012). We do not have any data on the prevalence of FASD in these communities. A more holistic view of the factors that lead some individuals to experience violence-related trauma, rather than an examination of cannabis (or alcohol, mental disorders, or experience of trauma) alone, is needed.

Limitations

Cannabis and alcohol use status was based on estimates made by local Aboriginal health workers and key community informants. However, these respondents have a good understanding of the substance use of individuals in these small and isolated communities given the established cultural practices in place, and this method has been previously validated (Clough et al., 2002; Clough, Cairney, et al., 2004) and used in research conducted in similar remote Aboriginal communities in northern Australia (Clough, D’Abbs, et al., 2004; Clough et al., 2006; Dingwall, Lewis, Maruff, & Cairney, 2010). It is unlikely that there was classification bias (with people more often engaged in violence being more likely to be classified as cannabis users by proxy respondents) because it is a small community with residents well aware of each other’s substance use patterns.

Trauma records were reliant on the client seeking help from the clinic and then on the trauma being recorded. It is likely that many more trauma incidents took place than those in which individuals involved actually presented for assistance. Data collected only allowed for a simple examination of the association between observed cannabis use status and the incidence of trauma presentations for individuals in the random sample. The study design does not permit a causal relationship between cannabis use and violence-related clinical presentations to be ascertained. No temporal relationship between cannabis use or cessation and involvement in violent trauma could be examined. We cannot say from these data whether this violent behaviour is triggered by a cannabis withdrawal syndrome (Budney, Moore, Vandrey, & Hughes, 2003; Kouri, Pope, & Lukas, 1999). Also, no longitudinal data on trends of cannabis trafficking and its association with trends in violent trauma during the study period were available. Care was taken to note verbatim description of incidents of violent trauma as they were recorded in medical records, and records indicated strongly that the presenting individuals were victims as opposed to perpetrators. However, it was not possible due to time constraints and opportunity to also conduct interviews with clinical staff or community members about these incidents to confirm this impression.

Data used in this study were collected in 2004–2006, however, verbal reports from community members and local services suggest that prevalence of cannabis use and violence-related trauma in these communities has not decreased since then. A small sample size and particularly small numbers of noncannabis users limited the range of analysis that could be conducted. However this randomly selected sample comprises 12% of the population in the targeted age groups.

Other than cannabis, alcohol, kava (in one community only), and nicotine use, there are no other confirmed reports of psychoactive substance use in the study communities. There may be a possibility that “sly grogging” (illicit sale, trade, or supply) of alcohol has led some local residents to have been engaged in violent incidents. Certainly, prior to July 2005, illicit supply of alcohol to this “dry” region was a common occurrence. However, based on police data (not shown) and community reports (with KC and KL), alcohol-related violence was relatively rare after July 2005.

Conclusion

The high prevalence of violent trauma in this sample raises concerns for the physical, social, and psychiatric burden on these vulnerable communities (Lee, Conigrave, et al., 2009; Select Committee on Substance Abuse in the Community, 2007; Wild & Anderson, 2007). A comprehensive and larger study is needed to explore the relationship between cannabis and violence. While we wait for this research to be conducted, given community reports of aggression seen in cannabis users, investment is also needed in local programmes to address cannabis use, other substance use, and the underlying risk factors for substance use and violence in remote Australia. Programmes may help mobilise communities to reduce cannabis-related harms and offer support for individuals who are dependent on cannabis and to tackle other antecedents and after-effects of violence. Working together and being led by communities who understand the context of these issues, we can begin to identify local solutions.

Footnotes

Acknowledgements

We thank the study communities, health clinics, and local research staff who contributed so much but remain anonymous. The assistance of Associate Professor Alan Clough (James Cook University, Queensland) who initiated the longitudinal study of cannabis use in these communities, Mira Branezac from New South Wales Health’s Drug and Alcohol Health Services Library, and the Foundation for Alcohol, Rehabilitation, and Education for their support of KL during data collection is greatly appreciated. KL is supported by an Australian National Health and Medical Research Council Postdoctoral Fellowship in Aboriginal and Torres Strait Islander health.

Funding

This research received the support of the Foundation for Alcohol, Rehabilitation and Education for KL during data collection. It also received support from the Australian National Health and Medical Research Council (NHMRC) for the larger longitudinal study of cannabis use from which these data have been extracted and for a Postdoctoral Fellowship in Aboriginal and Torres Strait Islander health for KL.

Note

Kylie Lee, PhD, BMus (Hons.), is an Australian National Health and Medical Research Council Postdoctoral Research Fellow in Aboriginal and Torres Strait Islander (Indigenous) Health and a Senior Lecturer in the Sydney Medical School at The University of Sydney. Dr. Lee’s research has focused on substance use and mental disorders among Indigenous Australians. This work draws on a unique blend of epidemiology and community development. Efforts in knowledge translation is a key aspect of her work to assist local communities to work towards change. This includes many Indigenous-led and award-winning health promotion videos that incorporate local concepts and language in remote northern Australia.

Krisakorn Sukavatvibul, MD, Grad Dip Clin Sc (Psychiatry), FRCPsychT, is a psychiatrist at Manarom Hospital in Bangkok, Thailand. Dr Sukavatvibul has an interest in addiction medicine and psychiatry. His research has focused on the treatment of mental health problems and substance use disorders. Dr Sukavatvibul’s current work focuses on clinical psychiatry, addiction medicine, and comorbidity.

Katherine Conigrave, FAChAM, FAFPHM, PhD, is an addiction medicine physician and public health physician at Royal Prince Alfred Hospital, Sydney. She is also conjoint professor in the Discipline of Addiction Medicine, Sydney Medical School, University of Sydney. Professor Conigrave’s research has focused on the epidemiology, prevention, early detection, and treatment of substance use disorders. This has included a focus on improving access to quality prevention and treatment services. In recent years Professor Conigrave’s work has focused on marginalised subpopulations and on populations from several different cultures. Professor Conigrave has worked in partnership with Aboriginal and Torres Strait Islander communities and agencies in Australia for more than a decade.

References

American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders Fifth Edition DSM-5. Retrieved from http://www.psych.org/File Library/Practice/DSM/DSM-5/DSM-5-TOC.pdf.

Australian Bureau of Statistics. (2005). Personal Safety Survey Australia (Catalogue No. 4906.0). Canberra, Australia: Author.

Australian Bureau of Statistics. (2008). Recorded crime, Indigenous Victims of crime (Catalogue No. 4510.0). Canberra: Author.

Budney

A. J.

Hughes

J. R.

(2006) The cannabis withdrawal syndrome. Current Opinion in Psychiatry 19: 233–238.

Budney

A. J.

Moore

B. A.

Vandrey

R. G.

Hughes

J. R.

(2003) The time course and significance of cannabis withdrawal. Journal of Abnormal Psychology 112(3): 393–402.

Clough

A. R.

Bailie

Burns

C. B.

Guyula

Wunungmurra

Wanybarrnga

S. R.

(2002) Validity and utlilty of community health workers’ estimation of kava use. Australian and New Zealand Journal of Public Health 26(1): 52–57.

Clough

A. R.

Cairney

D’Abbs

Parker

Maruff

Gray

O’Reilly

(2004) Measuring exposure to cannabis use and other substance use in remote Aboriginal populations in Northern Australia: Evaluation of a “community epidemiology” approach using proxy respondents. Addictions Research and Theory 12(4): 261–274.

Clough

A. R.

D’Abbs

Cairney

Gray

Maruff

Parker

O’Reilly

(2004) Emerging patterns of cannabis and other substance use in Aboriginal communities in Arnhem Land, Northern Territory: A study of two communities. Drug and Alcohol Review 23(4): 381–390.

Clough

A. R.

Lee

K. S. K.

Cairney

Maruff

O’Reilly

D’Abbs

Conigrave

K. M.

(2006) Changes in cannabis use and its consequences over three years in a remote Indigenous population in Northern Australia. Addiction 10(1): 696–705.

10.

Coffey

Carlin

J. B.

Degenhardt

Lynskey

Sanci

Patton

G. C.

(2002) Cannabis dependence in young adults: An Australian population study. Addiction 97(2): 187–194.

11.

Copeland

Swift

Rees

(2001) Clinical profile of participants in a brief intervention program for cannabis use disorder. Journal of Substance Abuse Treatment 20(1): 45–52.

12.

Crean

Crane

Mason

(2011) An evidence based review of acute and long-term effects of cannabis use on executive cognitive functions. Journal of Addiction Medicine 5(1): 1–8.

13.

Crowley

T. J.

Macdonald

M. J.

Whitmore

E. A.

Mikulich

S. K.

(1998) Cannabis dependence, withdrawal, and reinforcing effects among adolescents with conduct symptoms and substance use disorders. Drug and Alcohol Dependence 50(1): 27–37.

14.

Dingwall

Lewis

Maruff

Cairney

(2010) Assessing cognition following petrol sniffing for Indigenous Australians. Australian & New Zealand Journal of Psychiatry 44: 631–639.

15.

Hall, W., Degenhardt, L., & Lynskey, M. (2001). The health and psychological effects of cannabis use (2nd ed., Monograph Series No. 44). Canberra, Australia: Commonwealth Department of Health and Ageing.

16.

House of Representatives Standing Committee on Social Policy and Legal Affairs (2012) FASD: The Hidden Harm Inquiry into the prevention, diagnosis and management of fetal alcohol spectrum disorders, Canberra, Australia: Commonwealth of Australia.

17.

Hunter

E. M.

(1998) Considering trauma in an Indigenous context. Aboriginal and Islander Health Worker Journal 22(5): 9–17.

18.

Kouri

E. M.

Pope

H. G. J.

Lukas

S. E.

(1999) Changes in aggressive behaviour during withdrawal from long-term marijuana use. Psychopharmacology 143: 302–308.

19.

Lee

K. S. K.

Clough

A. R.

Conigrave

K. M.

Jaragba

M. J.

Dobbins

T. A.

Patton

G. C.

(2009) Five-year longitudinal study of cannabis users in three remote Aboriginal communities in Arnhem Land, Northern Territory, Australia. Drug and Alcohol Review 28: 623–630.

20.

Lee

K. S. K.

Clough

A. R.

Jaragba

M. J.

Conigrave

K. M.

Patton

G. C.

(2008) Heavy cannabis use and depressive symptoms in three Aboriginal communities in Arnhem Land, Northern Territory, Australia. Medical Journal of Australia 188(10): 605–608.

21.

Lee

K. S. K.

Conigrave

K. M.

Patton

G. C.

Clough

A. R.

(2009) Cannabis: Endemic yet neglected in remote Indigenous Australia [Editorial]. The Medical Journal of Australia 190(5): 228–229.

22.

Lee

K. S. K.

Freeburn

Ella

Miller

Perry

Conigrave

K. M.

(2012) Handbook for Aboriginal alcohol and drug work, Sydney, Australia: University of Sydney.

23.

Ministerial Council on Drug Strategy. (2006). National Drug Strategy Aboriginal and Torres Strait Islander Peoples Complementary Action Plan 2003–2009 (Background Paper). Canberra, Australia: Commonwealth of Australia.

24.

Moss

Tarter

(1993) Substance abuse, aggression, and violence. The American Journal on Addictions 2(2): 149–160.

25.

Patton

G. C.

Coffey

Carlin

J. B.

Degenhardt

Lynskey

Hall

(2002) Cannabis use and mental health in young people: Cohort study. British Medical Journal 325(7374): 1195–1198.

26.

Select Committee on Substance Abuse in the Community (2007) Substance abuse in remote communities: Confronting the confusion and disconnection , Darwin, Australia: Legislative Assembly of the Northern Territory.

27.

Swift

Hall

Didcott

Reilly

(1998) Patterns and correlates of cannabis dependence among long-term users in an Australian rural area. Addiction 93(8): 1149–1160.

28.

Wild, R., & Anderson, P. (2007). Ampe Akelyernemane Meke Mekarle: Little children are sacred (Report of the Northern Territory Board of Inquiry into the Protection of Aboriginal Children from Sexual Abuse). Darwin, Australia: Northern Territory Government.