Pathways to prevention: protocol for the CAP (Climate and Preventure) study to evaluate the long-term effectiveness of school-based universal, selective and combined alcohol misuse prevention into early adulthood

Table 1 Effect sizes and number needed to treat for changes relative to control group in any drinking, binge drinking and alcohol-related harms. Effect sizes are based on Intervention x Time coefficients from latent growth models used to analyze intervention outcomes [16, 58], converting the estimated odds ratios to standardised mean differences d [59]

Participants	Outcome	Intervention group	b	OR	d	NNT
All participants (at 24 months post baseline)	Any drinking	Climate^*	−0.38	0.47	−0.42	7
		Preventure^*	−0.36	0.49	−0.40	7
		CAP^*	−0.19	0.68	−0.21	12
	Binge drinking	Climate^*	−0.51	0.36	−0.56	9
		Preventure^*	−0.41	0.44	−0.45	10
		CAP^*	−0.36	0.49	−0.40	11
	Alcohol-related harms	Climate	−0.23	0.63	−0.25	10
		Preventure^*	−0.38	0.47	−0.42	6
		CAP	−0.19	0.68	−0.21	12
High-risk participants (at 36 months post baseline)	Any drinking	Preventure^*	−0.225	0.51	−0.37	7
	Binge drinking	Preventure^*	−0.305	0.40	−0.50	6
	Alcohol-related harms	Preventure^*	−0.255	0.47	−0.42	6

^*: significant at p < 0.05
b: Intervention x Time coefficient
OR: Estimated odds ratio
d: Estimated effect size (standardised mean difference)
NNT: Number needed to treat to benefit (based on OR and the event rate in the control group)

ISSN: 1471-2458