Table 3.

PAFs for daily use of cannabis and use of high-potency cannabis in the whole sample and by site

	Fully adjusted OR (95% CI)	Prevalence of exposure in controls	Prevalence of exposure in cases	PAF (95% CI)
High-potency cannabis (THC ≥10%)
Whole sample	1·6 (1·2–2·2)	19·1%	35·1%	12·2% (3·0–16·1)*
London (UK)	2·4 (1·4–4·0)	26·0%	51·5%	30·3% (15·2–40·0)*
Cambridge (UK)	1·3 (0·4–4·3)	11·0%	34·7%	8·2% (0·5–18·7)
Amsterdam (Netherlands)	3·6 (1·5–7·7)	54·0%	69·6%	50·3% (27·4–66·0)*
Gouda and Voorhout (Netherlands)	1·5 (0·8–3·1)	18·2%	36·0%	12·2% (8·7–25·3)*
Paris (Val-de-Marne; France)	2·1 (0·8–3·6)	21·0%	35·9%	18·9% (14·6–36·0)*
Puy de Dôme (France)	1·5 (0·4–5·8)	3·7%	7·1%	2·3% (0·6–17·2)
Madrid (Spain)	2·0 (0·7–5·7)	15·1%	34·0%	17·2% (0·9–25·0)
Barcelona (Spain)	1·6 (0·5–5·1)	7·8%	13·2%	4·7% (0·5–12·4)
Bologna (Italy)	1·2 (0·8–1·7)	8·7%	11·1%	1·9% (0·6–16·3)
Palermo (Italy)	0·6 (0·1–2·5)	5·2%	4·3%	Not calculated
Ribeirão Preto (Brazil)	2·1 (0·6–11·3)	1·5%	3·6%	1·9% (0·3–4·1)
Daily cannabis use
Whole sample	3·2 (2·2–4·1)	6·8%	29·5%	20·4% (17·6–22·0)*
London (UK)	3·6 (1·4–4·4)	11·7%	29·0%	21·0% (11·1–31·2)*
Cambridge (UK)	2·2 (0·8–6·5)	4·0%	20·2%	10·4% (4·7–21·0)*
Amsterdam (Netherlands)	7·1 (3·4–11·8)	13·1%	51·0%	43·8% (34·0–69·1)*
Gouda and Voorhout (Netherlands)	2·8 (1·4–20·3)	6·0%	27·0%	17·4% (1·1–23·1)*
Paris (Val-de-Marne; France)	2·8 (1·7–12·3)	11·6%	32·3%	20·8% (13·5–36·1)*
Puy de Dôme (France)	1·1 (0·4–12·2)	6·0%	11·0%	1·2% (0·8–15·4)
Madrid (Spain)	2·5 (2·1–7·3)	10·5%	21·2%	12·7% (3·7–14·2)*
Barcelona (Spain)	1·8 (0·8–8·7)	8·3%	18·9%	8·6% (0·6–9·9)
Bologna (Italy)	2·0 (0·5–5·8)	4·1%	17·3%	8·2% (0·8–11·7)
Palermo (Italy)	1·7 (0·7–9·7)	5·1%	17·1%	6·3% (0·9–21·1)
Ribeirão Preto (Brazil)	2·4 (1·5–7·5)	7·4%	25·0%	14·5% (10·2–24·1)*

OR=odds ratio. PAF=population attributable fraction.

^*p<0·05.