Tobacco use among adolescents in Scotland: profile and trends

APPENDIX A - EXPLANATORY NOTES AND BASES

A.1 NOTES TO AID INTERPRETATION

The combined SALSUS dataset provides a unique opportunity to investigate trends in tobacco use over a substantial period of time. All statistical analyses for this report were carried out using SPSS v16.0.1^[41] with the SPSS Regression Models package to enable logistic regression to be utilised. Graphs were produced using R version 3.1.2^[42] and RStudio version 0.98.1103,^[43] using the ggplot2 package,^[44] although no additional analyses were carried out in R. The majority of the work is descriptive with frequencies and crosstabs. Statistical analyses were carried out as part of the logistic regression.

Most of the report discusses questions which have been asked for at least 3 years - including in the 2013 survey. Any exceptions to this are noted. The majority of data presented is for 15 year olds only, since the small sample size of 13 year old regular smokers precludes meaningful analysis.

A core set of questions has remained constant throughout the entire run of the survey.^[45] Others have only been asked in certain years or have had variations in the wording of question or in what answer options were available for the question - for example, one year a child might be asked if a statement was true or false, in another they would be asked if they agreed or disagreed with it. There also may have been issues in how missing/not applicable responses were handled from year to year.

If the changes to the wording or format of a question was thought to impact the responses significantly, the answers were split into separate variables but kept in the data-set for use. A full explanation of how each variable was handled can be found in the user guide for this data set^[46] and possible sources of variation between years are noted in this report.

The sample size of the survey has varied over time. Until 1998, the sample size was between 2,000 and 3,000 interviews per wave. This increased to 3,538 and 4,774 in 2000. In 2002, to allow robust estimates at sub-Scotland level, the sample size was increased to 23,090. This was followed by sample sizes at similar levels in 2006 and 2010, with smaller samples in 2004 and 2008. There was no survey undertaken in 2012 and the 2013 wave was designed as a large rather than small wave, with a sample size of 33,685. The 2015 survey (currently in the field) is also a large wave.

The different sample sizes are taken into account in this analysis and bases noted where appropriate. The small sample sizes pre-2002 and in 2004/2008 mean only national estimates are possible - for sub-Scotland analysis and where the sample sizes are too small to obtain reliable figures, these data-points have been removed. Bases may vary from question to question due to questions not being answered by all respondents - e.g. some respondents did not say which gender they were, hence the total number of boys and girls does not equal the total number of responses. Total percentages may not always add up to 100% due to rounding.

A final note is that in 2002 and 2004, the questionnaire was answered by pupils in spring rather than autumn, meaning that pupils those years were on average 6 months older than in other years. As age is a key factor in smoking prevalence, this should be taken into account when viewing figures from those years.

A.2 BASES^[47]

Table A.1 - Bases for smoking status of 13 and 15 year olds

Year	13 Year Old	15 Year Old
1900	667	660
1992	737	630
1994	691	641
1996	622	594
1998	620	1116
2000	1207	1163
2002	12094	10219
2004	3469	3335
2006	11647	11072
2008	5327	4642
2010	19046	17772
2013	17085	16083

Table A.2 - Bases for smoking of 13 and 15 year olds of each gender

Year	13 Year Old		15 Year Old
	Boys	Girls	Boys	Girls
1900	324	343	343	317
1992	386	351	295	334
1994	349	342	311	330
1996	317	305	318	276
1998	306	314	562	554
2000	625	582	593	570
2002	5948	6146	5145	5074
2004	1783	1686	1646	1689
2006	5797	5774	5599	5410
2008	2631	2683	2296	2329
2010	9610	9394	9016	8685
2013	8515	8545	8083	7970

Table A.3 - Bases for parent(s), sibling(s), boy/girlfriend and best friend daily smoking

Relation that smokes daily	Classification	2002	2004	2006	2008	2010	2013
Parent(s)	All	10446	3402	11179	4630	17708	16066
	Regular	1988	627	1656	680	2274	1334
	Occasional	635	212	641	273	1152	706
	Non-smoker	7401	2438	8681	3649	14118	13824
Sibling(s)	All	7513	2400	7827	3311	12720	11743
	Regular	1432	463	1228	517	1674	976
	Occasional	445	152	442	205	776	476
	Non-smoker	5361	1700	6031	2579	10170	10169
Boy/girlfriend	All			5187	2168	8091	6363
	Regular			1076	462	1301	714
	Occasional			402	174	633	350
	Non-smoker			3612	1528	6082	5217
Best friend	All	9779	3113	10036	4228	16060	14448
	Regular	1937	612	1619	667	2205	1280
	Occasional	612	251	597	218	842	519
	Non-smoker	6856	2189	7640	3287	12648	12338

Table A.4 - Bases for smoking knowledge and attitudes statements

Statement	Classification	1994	1996	1998	2006	2008	2010
Smoking makes your clothes smell	Regular Smoker	134	172	271	1637	667	2265
	Occasional Smoker	48	53	85	641	265	1137
	Non-Smoker	458	369	750	8653	3577	14105
Smokers are more fun than non-smokers	Regular Smoker	130	169	265	1617	669	2240
	Occasional Smoker	48	52	85	629	262	1135
	Non-Smoker	456	368	748	8600	3568	14021
Smoking can cause lung cancer	Regular Smoker	134	172	273	1636	664	2265
	Occasional Smoker	48	53	85	639	266	1143
	Non-Smoker	457	369	749	8665	3582	14101
Smoking gives people confidence	Regular Smoker	132	169	273	1634	669	2242
	Occasional Smoker	47	53	84	635	261	1140
	Non-Smoker	453	367	744	8600	3551	14013
Smoking makes people worse at sport	Regular Smoker	134	171	272	1636	669	2261
	Occasional Smoker	48	53	85	640	265	1149
	Non-Smoker	458	369	749	8656	3575	14099
Smokers stay slimmer than non-smokers	Regular Smoker	130	168	270	1620	662	2238
	Occasional Smoker	46	52	85	634	261	1134
	Non-Smoker	453	366	739	8558	3544	13996
If a woman smokes when she is pregnant, it can harm her unborn baby	Regular Smoker	134	172	275	1641	665	2260
	Occasional Smoker	48	53	85	642	266	1151
	Non-Smoker	457	369	751	8670	3569	14112
Smoking helps people relax if they feel nervous	Regular Smoker	132	170	275	1632	670	2260
	Occasional Smoker	48	53	85	640	264	1145
	Non-Smoker	452	368	744	8598	3565	14032
Smoking can cause heart disease	Regular Smoker	134	171	273	1629	667	2257
	Occasional Smoker	48	53	85	638	260	1141
	Non-Smoker	453	369	750	8629	3559	14060
Smoking is not really dangerous, it only harms people who smoke a lot	Regular Smoker	133	171	274	1634	667	2257
	Occasional Smoker	48	53	85	636	263	1142
	Non-Smoker	457	369	749	8638	3576	14054
Smokers get more coughs and colds than non-smokers	Regular Smoker	134	169	268	1627	669	2250
	Occasional Smoker	58	52	84	634	264	1143
	Non-Smoker	452	366	745	8604	3560	14027
Other people's smoking can harm the health of non-smokers	Regular Smoker	134	170	272	1639	668	2256
	Occasional Smoker	46	50	82	613	250	1052
	Non-Smoker	455	369	748	8657	3570	14072
Smoking helps people cope better with life	Regular Smoker	131	167	269	1619	663	2238
	Occasional Smoker	48	53	84	633	261	1136
	Non-Smoker	455	367	743	8601	3559	14000

Table A.5 - Bases for parental knowledge of child's activities

Mother's Knowledge	Father's Knowledge	Gender	2002	2004	2006	2008	2010	2013
Below Median	Below Median	Male	1261	419	1367	524	1944	2452
		Female	1161	414	1466	570	2356	2057
	At Median	Male	321	94	227	158	373	550
		Female	167	108	294	105	363	317
	Above Median	Male	459	69	228	187	362	318
		Female	259	165	518	106	461	388
At median	Below Median	Male	210	102	354	81	539	358
		Female	318	90	265	112	536	543
	At Median	Male	87	43	127	46	211	254
		Female	106	33	98	78	226	197
	Above Median	Male	442	73	358	215	593	703
		Female	259	131	453	136	553	534
Above median	Below Median	Male	333	141	513	80	756	431
		Female	568	119	369	162	827	668
	At Median	Male	103	66	195	20	298	197
		Female	166	27	81	57	273	238
	Above Median	Male	1385	440	1499	494	2787	1574
		Female	1565	381	1229	525	2077	2077

Table A.6 - Bases for club/group attendance: regular smoking in those who attended or not

Club/group	Attended?	2006	2008	2010	2013
Youth group	Yes	2716	1024	4110	3217
	No	7611	3618	12839	12155
Drama, arts, music or singing group	Yes	2042	855	3284	3056
	No	8285	3787	13665	12316
Sports club, gyms, exercise or dance groups	Yes	5764	2537	9669	9309
	No	4563	2105	7280	6063
Computer clubs/groups	Yes	297	132	469	520
	No	10030	4510	16480	14852
None of these	Yes	7561	3523	12738	11980
	No	2766	1119	4211	3392

Table A.7 - Bases for excluded - change over time (left) and smoking status if excluded or not (right)

Graph	Category	2000	2002	2004	2006	2010	2013
Left	Regular	245	1805	591	1499	2054	1197
	Occasional	85	613	203	619	1083	668
	Non-Smoker	830	7266	2430	8405	13689	13463
Right	Yes	163	1073	401	1318	1365	802
	No	740	8611	2797	10070	14983	13803

Table A.8 - Bases for leisure activities: changes in proportion of respondents doing activities weekly between 2002 and 2013

Activity	2002	2004	2006	2008	2010	2013
See your friends	10095	3338	10549	4495	17242	15656
Listen to music	10096	3348	10536	4498	17250	15661
Look around the shops	10082	3329	10438	4479	17196	15632
Read comics or magazines	10069	3334	10428	4478	17193	15586
Read books	10045	3333	10366	4468	17163	15566
Go to watch sports matches	10057	3328	10399	4461	17161	15562
Go to the cinema	10053	3329	10390	4467	17157	15578
Hang around the street	10061	3334	10389	4465	17130	15537
Do a hobby, art or play a musical instrument	10045	3324	10365	4450	17119	15524
Go to a friend's house	10065	3332	10464	4465	17167	15575
Go to concerts or gigs	10047	3324	10366	4459	17126	15548
Go to the church, mosque or temple	10033	3319	10368	4459	17121	15503
Do nothing	10014	3298	10137	4355	16692	15065
Watch films or DVDs			10484	4496	17216	15628
Play computer games			10448	4470	17205	15565
Do a sport e.g. football etc		3329	10432	4466	17174	15580
Help other people, do voluntary work			10359	4446	17078	15481
Go online and use social networking sites (e.g. Facebook, Twitter)						15670
Go to a public library						15540
Go to a museum or gallery						15534
Go to theatres or concert halls						15514

Table A.9 - Bases for smoking frequency in 15 year olds by local authority

Local Authority	2002	2006	2008	2010	2013
Aberdeen City	413	633	140	493	399
Aberdeenshire	410	529	114	1293	681
Angus	363	179	116	286	415
Argyll and Bute	108	399	126	270	260
Clackmannanshire	174		22	115	508
Dumfries and Galloway	356	282	128	509	359
Dundee City	362	259	94	456	427
East Ayrshire	303	302	24	333	540
East Dunbartonshire	329	128	30	857	533
East Lothian	208	502	285	277	324
East Renfrewshire	342	385	56	416	797
Edinburgh City	538	531	235	1299	811
Eilean Saar		97	49	294	149
Falkirk	200	388	136	331	601
Fife	813	324	377	1081	804
Glasgow City	675	534	470	1024	1662
Highland	453	650	253	743	656
Inverclyde	219	490	103	287	175
Midlothian	271	228	45	542	318
Moray	302	244	69	293	395
North Ayrshire	212	269	160	412	443
North Lanarkshire	688	433	254	1160	791
Orkney	170	70	13	197	164
Perth and Kinross	305	485	134	359	297
Renfrewshire		266	206	652	79
Scottish Borders	345	281	89	338	672
Shetland	222	173	16	149	222
South Ayrshire	226	357	110	445	270
South Lanarkshire	511	568	347	1259	1087
Stirling	248	85	112	250	406
West Dunbartonshire	233	312	83	832	378
West Lothian	220	689	246	519	460
Scotland	10219	11072	4642	17772	16083

Table A.10 - Bases for smoking frequency in 15 year olds by health board

Local Authority	2002	2006	2008	2010	2013
Ayrshire and Arran	741	928	294	1190	1253
Dumfries and Galloway	356	282	128	509	359
Fife	813	324	377	1081	804
Forth Valley	622	473	270	696	1515
Grampian	1125	1406	323	2079	1475
Greater Glasgow and Clyde	1798	2115	948	4068	3624
Highland	561	1049	379	1013	916
Lanarkshire	1199	1001	601	2419	1878
Lothian	1237	1950	811	2637	1913
Orkney	170	70	13	197	164
Scottish Borders	345	281	89	338	672
Shetland	222	173	16	149	222
Tayside	1030	923	344	1101	1139
Eilean Siar	97	49	294	149	589
Scotland	10219	11072	4642	17772	16083

Table A.11 - Bases for Individual SDQ scores: regular smoker status in each banded score

SDQ Area	Banded Score	2006	2008	2010	2013
Emotional	Normal	8258	3595	13505	11033
	Borderline	674	330	1279	1354
	Abnormal	985	487	1876	2755
Conduct	Normal	6976	3217	12660	11829
	Borderline	1179	489	163	1425
	Abnormal	1773	708	2346	1910
Hyperactivity/ inattention	Normal	6459	2800	11108	10168
	Borderline	1310	589	2082	1981
	Abnormal	2129	1016	3459	2981
Peer Problems	Normal	8546	3896	14263	12097
	Borderline	1044	388	1795	2271
	Abnormal	321	124	601	779
Pro-social	Normal	6723	3100	11741	10942
	Borderline	1560	640	2429	2076
	Abnormal	1687	684	2520	2171

Table A.12 - Bases for regular smoking status range by SDQ score and gender

Gender	Banded Score	2006	2008	2010	2013
Male	Normal	3782	1654	6402	5651
	Borderline	665	274	1069	998
	Abnormal	415	210	763	827
Female	Normal	3462	1598	5895	4687
	Borderline	638	283	1003	1234
	Abnormal	583	243	1009	1413

Table A.13 - Bases for all deprivation graphs

Measure of Deprivation	Group Smoking	Category	2006	2008	2010	2013
SIMD	Child	1 - most deprived	1002	813	2390	2596
		2	1431	865	3817	2867
		3	1727	975	3770	3207
		4	1803	964	3727	3889
		5	1745	1025	4023	3524
	Parent(s)	1 - most deprived	1019	822	2418	2640
		2	1454	867	3856	2901
		3	1757	983	3802	3249
		4	1829	970	3753	3942
		5 - least deprived	1764	1029	4062	3556
Free school meals	Child	Yes	868	414	1713	1683
		No	9404	3962	14106	12598
	Parent(s)	Yes	886	415	1728	1706
		No	9550	3978	14226	12734
How well off would you say your family is?	Child	Very well off	1112	544	1499	1910
		Quite well off	4662	1904	6746	6175
		Average	4399	1863	7814	6721
		Not well off	439	192	831	707
		Not well off at all	99	39	202	165
	Parent(s)	Very well off	1140	545	1514	1930
		Quite well off	4722	1911	6806	6238
		Average	4472	1874	7881	6813
		Not well off	447	192	837	710
		Not well off at all	103	40	206	168