Data and methods


Age is calculated as at the start of the episode.

Data collection process

For most states and territories, the data provided for the national collection are a subset of a more detailed jurisdictional data set used for planning and policy. Figure A1 shows the processes involved in constructing the national data.

Figure A1: Alcohol and other drug treatment data collection flowchart

The flowchart depicts the collection process of the Alcohol and Other Drug Treatment National Minimum Dataset. At the state and territory level: collection of data by AOD agency staff; data collection form/electronic entry is forwarded to relevant state/territory health authority of central data collection point; data cleaning and validation; formation of the state/territory AOD databases; data analysis at the state/territory level; nationally agreed data is forwarded to the AIHW. At the AIHW: data cleaning and validation; annual formation of the AODTS NMDS.

Drugs of concern

The Alcohol and Other Drug Treatment Services National Minimum Data Set (AODTS NMDS) contains data on drugs of concern that are coded using the ABS Australian Standard Classification of Drugs of Concern (ASCDC) (ABS 2011). In this report, these drugs are grouped (Table A1).

Table A1: Groupings of drugs of concern
GroupASCDC codesCategoryIncludes
  Other opioidsOxycodone, fentanyl, pethidine
  Other analgesicsParacetamol
Sedatives and hypnotics2000–2999AlcoholEthanol, methanol and other alcohols
  BenzodiazepinesClonazepam, diazepam and temazepam
  Other sedatives and hypnoticsKetamine, nitrous oxide, barbiturates and kava
Stimulants and hallucinogens3000–3999AmphetaminesAmphetamine, dexamphetamine and methamphetamine
  Ecstasy (MDMA) 
  Other stimulants and hallucinogensVolatile nitrates, ephedra alkaloids, phenethylamines, tryptamines and caffeine
OtherAnabolic agents and selected hormones, antidepressants and antipsychotics, volatile solvents, diuretics and opioid antagonists
Not stated0000–0002Not stated 

In this report, pharmaceutical drugs were grouped using 10 drug types, making up the pharmaceuticals group for the purposes of the analysis. These drugs correspond to the ASCDC codes and classifications (Table A2).

Table A2: Pharmaceutical drugs of concern, ASCDC codes and classifications
Drug categoryASCDC code/th>ASCDC classification
(broad group and narrow group/s)
Drug description
(ASCDC base level unit/s)
Organic opiate analgesics
Organic opiate analgesics
Semisynthetic opioid analgesics
Semisynthetic opioid analgesics
Synthetic opioid analgesics
Benzodiazepines2400–2499Sedatives and hypnotics
Benzodiazepines n.f.d., alprazolam, clonazepam, diazepam, flunitrazepam, lorazepam, nitrazepam, oxazepam, temazepam, benzodiazepines n.e.c.
Steroids4000–4999Anabolic agents and selected hormones
Anabolic androgenic steroids
Beta2 agonists
Peptide hormones, mimetics and analogues
Other anabolic agents and selected hormones
Not further defined
Anabolic agents and selected hormones n.f.d., anabolic androgenic steroids n.f.d., boldene, dehydroepiandrosterone, fluoxymesterone, mesterolone, methandriol, methenolone, nandrolone, oxandrolone, stanozolol, testosterone, anabolic androgenic steroids n.e.c., beta2 agonists n.f.d., eformoterol, fenoterol, salbutamol, beta2 agonists n.e.c., peptide hormones, mimetics and analogues n.f.d., chorionic gonadotrophin, corticotrophin, erythropoietin, growth hormone, insulin, peptide hormones, mimetics and analogues n.e.c., other anabolic agents and selected hormones n.f.d., sulfonylurea hypoglycaemic agents, tamoxifen, thyroxine, other anabolic agents and selected hormones n.e.c.
Other opioids1100, 1199, 1200, 1299, 1300–1304, 1306–1399Analgesics
Organic opiate analgesics
Semisynthetic opioid analgesics
Synthetic opioid analgesics
Not further defined
Organic opiate analgesics n.f.d., organic opiate analgesics n.e.c., semisynthetic opioid analgesics n.f.d., semisynthetic opioid analgesics n.e.c., synthetic opioid analgesics n.f.d., fentanyl, fentanyl analogues, levomethadyl acetate hydrochloride, meperidine analogues, pethidine, tramadol, synthetic opioid analgesics n.e.c.
Other analgesics0005, 1000, 1400–1499Analgesics
Non-opioid analgesics
Not further defined
Analgesics n.f.d., non-opioid analgesics n.f.d., acetylsalicylic acid, paracetamol, ibuprofen, non-opioid analgesics n.e.c.
Other sedatives and hypnotics2000, 2200–2299, 2300–2399, 2500–2599, 2900–2999Sedatives and hypnotics
Gamma-hydroxybutyrate (GHB) type drugs and analogues
ther sedatives and hypnotics
Sedatives and hypnotics n.f.d., anaesthetics n.f.d., ketamine, nitrous oxide, phencyclidine, propofol, anaesthetics n.e.c., barbiturates n.f.d., amylobarbitone, methylphenobarbitone, phenobarbitone, barbiturates n.e.c., GHB-type drugs and analogues n.f.d., GHB, gamma-butyrolactone, 1,4-butanediol, GHB-type drugs and analogues n.e.c., other sedatives and hypnotics n.f.d., chlormethiazole, kava lactones, zopclone, doxylamine, promethazine, zolpidem, other se

n.f.d – not further defined; n.e.c – not elsewhere classified.

Jurisdictional notes regarding principal drug of concern:

  • South Australia reports a high proportion of treatment episodes where amphetamines are the principal drug of concern due to the SA Police Drug Diversion Initiative (PDDI). In addition, adult cannabis offences are not included in the PDDI due to the SA Cannabis Expiation Notice legislation.
  • Victoria reported a high number of miscellaneous episodes coded as ‘Other drugs’ due to service provider reporting practices and limitations with the reporting system. This system was replaced in 2019–20. In 2019–20 and 2020–21, Victoria continued to report high levels of miscellaneous episodes coded as ‘Other drugs’ or ‘Not stated’ as principal drugs of concern due to service provider reporting practices with the new data reporting system.
  • In Queensland, the proportion of cannabis episodes reported as the principal drug of concern is a result of the Police Drug Diversion Program, Illicit Drugs Court Diversion Program and Drug and Alcohol Assessment Referral Program (DAAR) operating in the state.
  • In the Australian Capital Territory, removal of criminal penalties for possession of small quantities of cannabis in the ACT at the end of January 2020 reduced the number of cannabis-related diversions recorded as treatment episodes to low levels (mainly under-18s). Data collection improvements at government-operated services resulted in fewer ‘not stated’ responses in the 2022–23 collection.

Drugs of concern supplementary tables

Data for drugs of concern published in the supplementary tables may differ from results published within other tables, due to different counting methodology. Tables have been footnoted where there is different counting methodology. For example, where the principal drug of concern is coded as fentanyl (1301) and other drug of concern is coded as tramadol (1307), these drugs are within the same drug grouping (synthetic opioid analgesics) and counted only once.


Duration is calculated in whole days, and only for closed episodes.

Population rates

In this publication, crude rates were calculated using the ABS’s estimated resident population at the midpoint of the data range: that is, rates for 2022–23 data were calculated using the estimated resident population at31 December 2022. Rates for previous years may differ to previously reported due to updated estimated resident population.

The COVID-19 pandemic and the resulting Australian Government closure of the international border from 20 March 2020, caused significant disruptions to the usual Australian population trends. This report uses Australian Estimated Resident Population (ERP) estimates that reflect these disruptions.

In the year July 2020 to June 2021, the overall population growth was much smaller than the years prior and in particular, there was a relatively large decline in the population of Victoria. ABS reporting indicates these were primarily due to net-negative international migration (National, state and territory population, June 2021).

Please be aware that this change in the usual population trends may complicate interpretation of statistics calculated from these ERPs. For example, rates and proportions may be greater than in previous years due to decreases in the denominator (population size) of some sub-populations.

Reason for cessation

The AODTS NMDS contains data on the reason an episode ended (reason for cessation). In this report, these reasons are grouped (Table A3), but data for the individual end reasons are available in the online supplementary tables.

A different method was used for grouping end reasons in reports released before 2014, so trend comparisons across reports should be made with caution. It is possible to compare data at the individual end reasons using the supplementary tables.

Table A3: Grouping of cessation reasons, by indicative outcome type

Outcome type/th>

Reason for cessation/th>

Expected/planned completionTreatment completed
 Ceased to participate at expiation
 Ceased to participate by mutual agreement
Ended due to unplanned completionCeased to participate against advice
 Ceased to participate without notice
 Ceased to participate due to non-compliance
Referred to another service/change in treatment modeChange in main treatment type
 Change in delivery setting
 Change in principal drug of concern
 Transferred to another service provider
OtherDrug court or sanctioned by court diversion service
 Imprisoned (other than drug court sanctioned)
 Not stated

Remoteness area

This report uses the ABS’s Australian Statistical Geography Standard (ASGS) Edition 3 (ABS 2021) to analyse the proportion of AOD treatment agencies by remoteness area. This structure allows areas that share common characteristics of remoteness to be classified into broad geographic regions of Australia. These areas are:

  • Major cities
  • Remote
  • Inner regional
  • Very remote
  • Outer regional

The remoteness structure divides each state and territory into several regions based on their relative access to services.

Examples of urban centres in each remoteness area are:

  • Major cities          Canberra, Newcastle
  • Inner regional      Hobart, Bendigo
  • Outer regional     Cairns, Darwin
  • Remote                 Katherine, Mount Isa
  • Very remote          Tennant Creek, Meekatharra.

For this report, the remoteness area of the agency was determined using the Statistical Area Level 2 (SA2) of the agency. Not all SA2 codes fit neatly within a single remoteness category, and a ratio is applied to reapportion each SA2 to the applicable remoteness categories. As a result, it is possible that the number of agencies in a particular remoteness category is not a whole number. After rounding, this can result in there being ‘<0.5%’ agencies in a remoteness area, due to the agency’s SA2 partially crossing into the remoteness area.

The Australian Statistical Geography Standard ASGS has replaced the Australian Standard Geographical Classification 2006 (ABS 2006), which was used in previous reports to calculate remoteness areas. Therefore, remoteness data for 2011–12 and previous years are not comparable with those for 2012–13 and subsequent years.

Service sectors

From 2008–09, agencies funded by the Department of Health under the Non-Government Organisation Treatment Grants Program (NGOTGP) were classified as non‑government agencies. Before this, many of these agencies were classified as government agencies. As a result, trends in service sectors of agencies should be interpreted with caution.

Source of referral: diversion

Throughout Australia, there are programs that divert people who have been apprehended or sentenced for a minor drugs offence from the criminal justice system. Many of these diversions result in clients receiving drug treatment services, who have been referred to treatment agencies as part of a drug diversion program. Since the 1980s, Australian governments have supported programs aimed at diverting from the criminal justice system people who have been apprehended or sentenced with a minor drugs offence.

In Australia, drug diversion program come in 2 main forms:

  • Police diversion occurs when an offence is first detected by a law enforcement officer. It usually applies for minor use or possession offences, often relating to cannabis, and can involve the offender being cautioned, receiving a fine and/or having to attend education or assessment sessions.
  • Court diversion occurs after a charge is laid. It usually applies for offences where criminal behaviour was related to drug use (for example, burglary or public order offence). Bail-based programs generally involve assessment and treatment, while pre‑ and post-sentence programs (including drug courts) tend to involve intensive treatment and are aimed at repeat offenders.


The number of closed treatment episodes for counselling as a main treatment type has remained the most common treatment type for all clients over all collection years. Fluctuations over time in closed treatment episodes for particular treatment types may be influenced by coding practices, increased funding or changes in treatment policies or capacity to provide specialised alcohol and other drug treatment services, which may contribute to variation in treatment types over time.

Trend data may differ from data published in previous versions of Alcohol and other drug treatment services in Australia, due to data revisions.

Imputation methodology for AOD clients

From the inception of the AODTS NMDS, data have been collected only about treatment episodes provided by AOD treatment services. Data about the clients those episodes relate to have not been available at a national level. A Statistical Linkage Key-581 (SLK) was introduced into the AODTS NMDS for the 2012–13 collection to enable the number of clients receiving treatment to be counted, while continuing to ensure the privacy of these individuals receiving treatment.

An imputation strategy for the collection was developed to correct for the impact of invalid or missing SLKs on the total number of clients. This strategy takes into account several factors relating to the number of episodes per client and makes assumptions relating to spread across agencies. It also takes into consideration the likelihood that an episode with a missing SLK relates to a client that has already been counted through other episodes with a valid SLK.

To ensure an accurate representation of the AODTS client population, imputation was applied to the 2012–13, 2013–14 and 2015–16 AODTS NMDS to account for the proportion of valid SLKs being less than 95% for these years. The national rate of valid SLKs for these years was largely affected by low proportions of valid SLKs in New South Wales.

Historical data element changes 

Details on historical data element changes are found in Appendix A of the AODTS NMDS Data Collection Manual 2022–23.