Table 2 Characteristics of included studies

Carr 1992 [42]

Individually randomised trial

Olympic Training Centre (OTC) in Colorado Springs, Colorado, USA.

Eight resident teams of elite athletes representing archery, gymnastics, shooting, table tennis and handball.

Intervention group: 30 athletes; control group: 23 athletes

Age: mean 21.3 (SD 4.1)

Gender: males 59 %, females 41 %

Inclusion criteria: athletes in resident training programmes at the OTC.

Intervention condition: multimodal substance abuse programme based on a cognitive-behavioural model, which included:

• education component (2.5 h)

• decision-making/coping skills component (3 h)

• social skills/self-esteem component (2.5 h).

Each component included lecture presentations, group discussions, role-play exercises, and written materials.

Control condition: no intervention. Intervention offered after trial period.

All outcomes were assessed at pre-test, post-test and at the end of a 7-week follow-up period via self-completed questionnaires.

• Frequency of use of alcohol in the last month

• Change score for frequency of use in alcohol in the last month from pre-test to follow-up, coded as:

1 = decrease in use

2 = no change

3 = increase

Kingsland et al. 2015 [44]

Cluster randomised controlled trial

Non-elite, community football clubs within the Hunter, New England and Sydney regions of New South Wales, Australia

Eighty-eight football clubs (rugby league, rugby union, soccer/association football and Australian rules football) and club members.

Intervention group: 43 clubs; 700 members at pre-intervention cross section; 567 members post-intervention cross section.

Control group: 45 clubs; 711 members pre-intervention cross section; 577 members post-intervention cross section.

Members pre-intervention:

Age: average 30 years+

Gender: intervention group 77.4 % male; control group 87 % male)

Role: intervention group 60 % players, 26 % members/supporters, 14 % officials; control group 47 % players, 36 % members/supporters, 17 % officials.

Inclusion criteria:

Clubs: community level, non-elite football clubs who had over 40 members, sold alcohol and were not participating in an alcohol management improvement program.

Members: club member who were 18+ years and spoke English

Intervention condition:

2.5 year accreditation programme which included:

• Adherence to liquor licence requirement in terms of signage and alcohol service hours and areas

• Staff trained in responsible service of alcohol

• Water and substantial food is provided

• Intoxicated people not permitted to enter, not served alcohol and not permitted to remain at the club

• Alcoholic drinks are only served in standard drink measures

• Club maintains a register of alcohol-related incidents

• Bar servers do not consume alcohol

• Non-alcoholic drinks and low-alcoholic drinks are available and are cheaper than full-strength alcoholic drinks

• Club does not serve ‘shots’ or double-nips of alcohol or ready-to-drink products over 5 % alcohol/volume

• Club does not conduct drinking games/promotions that encourage risky alcohol consumption

• Club has some sponsorship that is not from the alcohol industry

• Club has developed a written alcohol management policy and distributed it to members.

Implementation supports: based on theoretical frameworks for organisational change and consisted of: project officer support, implementation cost recovery, accreditation and associated merchandise, printed resources and newsletters, observational audits and feedback online training and letters of support from state sporting organisation.

Control condition: control (and intervention) clubs were given printed resources on topics unrelated to the trial outcomes.

All outcomes were assessed at pre- and post-intervention using self-reported measures collected via telephone survey.

• Risky alcohol consumption defined as ≥5 standard drinks on the one occasion

• Alcohol Use Disorders Identification Test (AUDIT):

▪ Median total AUDIT score

▪ Total AUDIT score of ≥8 (indicative of hazardous consumption)

▪ Alcohol consumption subscale (score ≥6 for items 1–3)

▪ Dependency subscale (score of ≥4 for items 4–6)

▪ Alcohol-related problems subscale (score ≥1 for items 7–10).

All outcome analyses adjusted for clustering and pre-intervention values.

O’ Farrell 2010 [43]

Cluster randomised controlled trial

Gaelic Athletic Association (GAA) amateur sporting clubs in the Republic of Ireland.

Forty-one hurling, Gaelic football and handball clubs within two counties in Ireland and club players.

Intervention group: 12 clubs; 332 members at pre-intervention; 218 members post-intervention.

Control group: 29 clubs; 628 members pre-intervention; 441 members post-intervention.

Players pre-intervention:

Mean age: 24 years

Gender: All male

Inclusion criteria: clubs: within two study counties in Ireland

Players: uninjured GAA male club players aged 16 years and above.

Intervention condition:

Community mobilisation approach targeting the club environment and individual player behaviour implemented over four months. Intervention included:

• Alcohol education for the players (1x50mins)

• Alcohol education for coaches (1x40mins)

• Alcohol policy training for club managers and coaches (1 × 40 min)

• Alcohol information media campaign

Implementation supports: health promotion staff, presentation materials, handouts and advertising materials.

Control condition: control (and intervention clubs) received an education session on sports nutrition.

All outcomes were assessed at pre- and post-intervention using self-reported measures via paper questionnaires:

• Alcohol use disorder identification test (AUDIT):

▪ Mean total AUDIT score

▪ Total AUDIT score of ≥ 8

▪ AUDIT hazardous alcohol use subscale (score ≥6 for items 1–3)

▪ AUDIT dependency subscale (score ≥4 for items 4–6)

▪ AUDIT harmful alcohol use subscale (score ≥1 for items 7–10).

• Yearly alcohol consumption (litres of pure alcohol)

• ≥21 standard drinks per week

• Binge drinking (≥6 drinks one sitting)

• Mean alcohol-related harms score (of total of 13)