. 2018 Nov 5;29(3):453–457. doi: 10.1093/eurpub/cky230

Table 2.

Longitudinal retrospective analysis: adjusted odds ratio of daily smoking between ages 10 and 39 years for immigrants according to their lifecycle stage relative to time of migration, based on smoking and migration history (individuals aged 18–70 years)

	Men			Women
	Odds ratio	95% CI	Trend test	Odds ratio	95% CI	Trend test
Immigrants from the Maghreb
External analysis^a
Native-born (reference)	1.00			1.00
Before migration	0.61	[0.39–0.95]		0.03	[0.01–0.09]
0–5 years after migration	0.57	[0.40–0.81]		0.07	[0.03–0.16]
6–9 years after migration	0.96	[0.65–1.42]		0.17	[0.09–0.33]
10 years + after migration	1.54	[1.09–2.17]		0.52	[0.33–0.81]
Internal analysis for immigrants^b
Before migration (reference)	1.00		Linear	1.00		Linear
0–5 years after migration	0.92	[0.59–1.43]	P = 0.467	2.98	[0.75–11.81]	P = 0.284
6–9 years after migration	1.39	[0.76–2.54]	Quadratic:	6.39	[1.58–25.85]	Quadratic
10 years + after migration	1.82	[0.96–3.46]	P = 0.021	16.73	[3.88–72.04]	P = 0.000
Immigrants from sub-Saharan Africa
External analysis^a
Native-born (reference)	1.00			1.00
Before migration	0.34	[0.17–0.70]		0.03	[0.01–0.08]
0–5 years after migration	0.25	[0.15–0.44]		0.19	[0.10–0.35]
6–9 years after migration	0.27	[0.14–0.51]		0.30	[0.17–0.55]
10 years + after migration	0.36	[0.19–0.68]		0.70	[0.37–1.32]
Internal analysis for immigrants^b
Before migration (reference)	1.00		Linear	1.00		Linear
0–5 years after migration	0.64	[0.31–1.33]	P = 0.187	8.00	[3.08–20.79]	P = 0.001
6–9 years after migration	0.66	[0.24–1.81]	Quadratic:	12.90	[4.49–37.06]	Quadratic
10 years + after migration	0.83	[0.27–2.53]	P = 0.824	27.25	[8.24–90.08	P = 0.000

Weighted discrete time logistic regression with adjustment on age at follow-up, age at follow-up², relative educational level, birth cohort group (1940–55; 1956–70; 1971–92) and relative age in birth cohort group. The sample comprised the native-born and immigrants from the Maghreb (top half of the table) and; the native-born and immigrants from sub-Saharan Africa (bottom half of the table). Example: before migration, immigrant men from the Maghreb had an OR of daily smoking of 0.61 compared to the native-born.

The model described in (a) was run on a sample restricted to the immigrants using the period before migration as the reference. Example: within 5 years from arrival in France, the OR of daily smoking in immigrant men from the Maghreb was 0.92 relative to the period before migration.