Table 1 Eligibility criteria (PICOS)

Participants and Population

University students enrolled in a tertiary education institution, namely a ‘university’ or ‘college’.

Intervention

Behavioural interventions implemented within a university setting, targeting one or more health behaviours of interest (i.e., dietary intake, physical activity, sedentary behaviour, alcohol intake, sleep, smoking status, or drug use) were included.

Comparator

Any comparator/control was considered for inclusion.

Outcomes

Studies reporting change in both health behaviours and mental health outcomes were included:

• Dietary intake: Changes in energy, macro/micronutrients, food group intake, diet quality, and dietary patterns

• Physical activity: Changes in total energy expenditure, frequency and duration of physical activity

• Sedentary behaviour: Changes in frequency and duration of sitting time or recreational screen time

• Alcohol intake: Changes in frequency and quantity of alcohol intake

• Sleep: Sleep duration, quality, timing and alertness

• Smoking status: Changes in tobacco smoking, or e-cigarette use

• Drug use: Changes in frequency and quantity of use of illegal drugs, misuse or non-medical use of pharmaceutical drugs, or inappropriate use of other substances such as inhalants

• Mental health: Psychological wellbeing (i.e. Changes in hedonic (e.g., happiness, positive emotions) and/or eudemonic (e.g., self-acceptance, autonomy) domains of wellbeing) and mental illness/ mental health disorder (i.e. Changes in symptoms/severity/diagnosis of all psychiatric disorders as per DSM-IV-TR)

Study Design

Randomized controlled trials (RCTs) including feasibility and pilot RCTs. Quasi and pseudo RCTs were excluded.