TEDS Data Dictionary

16 Year Measures

Contents of this page:

Introduction

The tables below summarise the measures used in the 16 Year study. In each table, measures are variously identified by measure/activity name, page number (in booklets) and/or screen number (in web questionnaires). The number of items in each measure is shown, but note that some of these items have two or more parts, giving two or more item variables.

If you wish to include any of the 16 year measures in a new project, please consult with the relevant TEDS research leader first, as these data have only recently been released for analysis. For example, please consult with Angelica Ronald if you wish to use any of the psychotic experiences measures from the 16 year data.

The final column of each table shows dataset scales that are related to each measure; each variable name here is a link that will take you to the relevant paragraph in the 16 Year derived variables page.

Web Study: Cognitive Test Measures

The table below lists measures use in the twin cognitive web tests. The web study questionnaire measures (parent SES, twin Environment and Wellbeing) are shown separately further down this page.

Activity name(s) Category No. of items Description of measure References Related scales
Understanding Number

(Maths)		 Mathematics test 18 Based on NFER-Nelson Maths 5-14 Series, which is linked closely to curriculum requirements in the UK and the English Numeracy Strategy.
The items were taken from National Foundation for Educational Research (NFER) booklets 8 to 14.

This is much-reduced version of the Mathematics web test used in the 12 Year study: only one of the three sub-tests (Understanding Number) is retained, easier items were removed and more difficult items added, and the test rules were adapted.
For a full description of the test, see the Understanding Number web test page.

The booklets Mathematics 8 through to Mathematics 14 each have the following components, all published by NferNelson Publishing Company Ltd:

  • Curriculum Links Sheet: © NFER (2001)
  • Items: most items © NFER (1999, 1998 or 1994), remaining items © Peter Patilla (1994)
  • Test selection and arrangement: © NFER and Peter Patilla (1994, 1998 or 1999)
  • Teacher’s Guides: Hagues, N., Courtenay, D., and Patilla, P. (1994) for books 7-11, Mason, K., Hagues, N. & Patilla, P. (1998) for books 12-14.
 Adjusted Understanding Number test score:pcuntota1/2

Understanding Number test mean item answer time pcunatm1/2
Dot Number Matching

(Dots and Numbers)		 Numerical test 36 For a full description of this test, see the Dot Number web test page. The task has been programmed to match the one present on the website of our collaborators in Hong Kong: http://lab.kctam.com/stroop Dot Number test mean item answer time pcdnatm1/2
Dot Task

(Number Sense)		 Numerical test 150 For a full description of this test, see the Number Sense web test page. Halberda, J., Mazzocco, M. and Feigenson, L. (2008). Individual differences in nonverbal estimation ability predict maths achievement. Nature, 455,665-668. Weber fraction scores: pcnswebcor1/2, pcnswebunc1/2

Dot Task mean item answer time pcnsatm1/2
Corsi Tapping Block

(Sequences)		 Numerical test 18 The Corsi paradigm is described in reference 1.

We have adapted the test trials using the method described in reference 2.

For a full description of this test, see the Corsi Block web test page.
  1. Corsi, P. M. 1972. Human memory and the medial temporal region of the brain. Dissertation Abstracts International, 34 (02), 891B.
  2. Pagulayan, K.F., Busch, R. M., Medina, K. L., Bartok, J. A. and Krikorian, R. (2006). Developmental Normative Data for the Corsi Block-Tapping Task. Journal of Clinical and Experimental Neuropsychology. 28 (6),1043 - 1052.
 Corsi Block test mean item answer time pccbatm1/2
Problem Verification Task

(PVT, Right or Wrong?)		 Numerical test 48 For a full description of this test, see the PVT web test page. Murphy, M. M., and Mazzocco, M. M. M (2008). Mathematics Learning Disabilities in Girls With Fragile X or Turner Syndrome During Late Elementary School. Journal of Learning Disabilities, 41 (1), 29-46. PVT mean item answer time pcpvatm1/2
Number Line Numerical test 22 For a full description of this test, see the Number Line web test page. Siegler, R. S. and Opfer, J. E. (2006). Representational change and children’s numerical estimation. Cognitive Psychology. doi:10.1016/j.cogpsych.2006.09.002. Number Line test mean item answer time pcnlatm1/2
Reaction Times Numerical test 40 For a full description of this test, see the Reaction Times web test page. Deary, I. J., Der, G., Ford, G. (2001). Reaction times and intelligence differences. A population-based cohort study. Intelligence, 29, 389–399. Reaction Time test mean item answer time pcrtatm1/2
Ravens Progressive Matrices

(Patterns)		 Cognitive test
(non-verbal)		 30 Ravens Standard Progressive Matrices.

This is identical to the 14 Year version of the Ravens web test, apart from minor changes to the test introduction.

For a full description of the test, see the Ravens web test page.		 Raven, J.C., Court, J.H., and Raven, J. (1996), Manual for Raven's Progressive Matrices and Vocabulary Scales, Oxford: Oxford University Press. Adjusted Ravens test score:pcrvtota1/2

Ravens test mean item answer time pcrvatm1/2
Mill Hill

(Vocabulary)		 Cognitive test
(verbal)		 33 Mill Hill Vocabulary Scale.

Like the WISC vocabulary test used in earlier TEDS web studies, this is a simple multiple-choice test of vocabulary.

For a full description of the test, see the Vocabulary web test page.		 Raven, J, Raven, JC, and Court, JH (1998). Mill Hill vocabulary scale. Oxford: OPP. Adjusted Vocabulary test score: pcvctota1/2

General cognitive ability score (g), based on the Vocab and Ravens scores:
pcg1/2

Vocabulary test mean item answer time pcvcatm1/2
Yes/No

(Reading Fluency)		 Reading test 98 Woodcock-Johnson III Reading Fluency

This is an adapted version of the 12 year version of the Yes/No web test; the design of the test is the same, although the time limit was reduced from 3 minutes to 2 and a half minutes.
For a full description of the test, see the Yes/No web test page.		 Woodcock, R. W., McGrew, K. S., and Mather, N. (2001). Woodcock-Johnson III. Itasca, IL: Riverside Publishing Yes/No test mean item answer time pcynatm1/2
RC-16

(Passages, Reading Comprehension)		 Reading test 26 The RC-16 (Reading Comprehension, age 16) multiple-choice reading comprehension web test was developed by Emma Hayiou-Thomas and Philip Dale, based on passages and suggested questions generously shared with TEDS by Dr. Maggie Snowling, York University.

For a full description of the test, see the Passages web test page.		 - Passages test mean item answer time pcpsatm1/2
Expressions

(Figurative Language)		 Language test 15 Test of Language Competence (Expanded Edition). Semantics: The Figurative Language subtest.

This is an adapted version of the 12 year version of the Expressions test; some easier items were removed and some harder items added. The new items were not part of the published measure, but were invented by TEDS researchers.

For a full description of the test, see the Expressions web test page.		 Wiig, E.H., Secord, W., and Sabers, D. (1989). Figurative Language subtest. From the Test of Language Competence – Expanded Edition. San Antonio, TX, The Psychological Corporation. Expressions test mean item answer time pcflatm1/2

Web Study: Questionnaire Measures

The table below lists measures use in the parent web SES questionnaire and in the four twin environment and wellbeing questionnaires part A, part B, part C and part D (pdfs).

Note that the web study only involved TEDS cohorts 1 and 2, so data are not present for families in cohorts 3 and 4.

Questionnaire Screen no. Category No. of items Description of measure References Related scales
Parent SES questionnaire - Family environment 5
  1. Household income scale
    (devised by TEDS researchers)
  2. Mother and father highest level of educational qualifications
    (adapted from the equivalent measure used in TEDS at 1st Contact and in the 7 year parent booklet)
  3. Mother and father employment categories, related to the SOC scale

This web questionnaire was placed on the same page as the parental consent form, so was completed for all families participating in the web study. For a full description of this page, see the parent consent and SES page.

 The employment category responses are based on the major groups in the SOC classification: see SOC 2000 (Standard Occupational Classification 2000). Composite SES score based on these parent measures:
pses
Environment and Wellbeing Questionnaire part A

(About You, EWQ A)		 2 Wellbeing 21 Life Satisfaction: Multidimensional students’ life satisfaction scale (reduced from 40 to 21 items after pilot study) Huebner (1994). Preliminary development and validation of a multidimensional life satisfaction scale for children. Psychological Assessment, 6, 149-158. Life satisfaction scales:
pclsfamm1/2, pclsfrnm1/2, pclslvem1/2, pclsschm1/2, pclsslfm1/2, pclsm1/2
3 Wellbeing and other 4
  1. Health (1 item)
  2. Eyesight (3 items), adapted from Walline et al)
  1. Ravens-Sieberer and the KIDSCREEN Group (2004).
  2. Walline, JJ, Zadnik, K, and Mutti, DO (1996) Validity of surveys reporting myopia, astigmatism, and presbyopia. Optometry and Vision Science, 73(6), 376-381.
 -
4 Home environment 6 CHAOS (Confusion, Hubbub and Order Scale) at home, adapted from the full-length version as in the TEDS 14 Year booklets. Matheny, Wachs, Ludwig and Phillips (1995). Bringing order out of chaos: Psychometric characteristics of the Confusion, Hubbub and Order Scale. Journal of Applied Developmental Psychology, 16, 429 - 444. Chaos scale:
pcchatot1/2
5 Home environment 8 Screen time From NICHD early childcare and youth development study -
6 Wellbeing 6 Hopefulness Snyder et al. (1997). The development and validation of the Children’s Hope Scale. Journal of Paediatric Psychology, 22, 399-421. Hopefulness scales:
pchopeagm1/2, pchopepam1/2, pchopem1/2
7 Wellbeing 13
  1. Gratitude (6 items)
  2. Curiosity: exploration and flow (7 items)
  1. McCullough, M. E., Emmons, R. A., and Tsang, J. (2002). The grateful disposition: A conceptual and empirical topography. Journal of Personality and Social Psychology, 82, 112-127.
  2. Kashdan, T.B., Rose, P., and Fincham, F.D. (2004). Curiosity and exploration: Facilitating positive subjective experiences and personal growth opportunities. Journal of Personality Assessment, 82, 291-305.
  1. Gratitude scale: pcgratm1/2
  2. Curiosity scales: pccuriexm1/2, pccuriflm1/2, pccurim1/2
8 Wellbeing 4 Subjective happiness Lyubomirsky, S., and Lepper, H. S. (1999). A measure of subjective happiness: Preliminary reliability and construct validation. Social Indicators Research, 46, 137-155. Subjective happiness scale: pcshsm1/2

Wellbeing composites, derived from various wellbeing measures listed above or below on this page:
pcwbpsym1/2, pcwbsubm1/2
Environment and Wellbeing Questionnaire part B

(Your School, EWQ B)		 2 School environment 19 School engagement. This measure includes 5 subscales: teacher-student relations; control and relevance of school work; peer support for learning; future aspirations/goals; family support for learning. (After the pilot study, the number of items was halved from the original measure, while retaining items from each of the 5 subscales.)

In addition to the 19 items for this measure there is an "opt-out" item for twins to tick in case they are home-educated.		 Appleton et al. (2006). Measuring cognitive and psychological engagement: Validation of the Student Engagement Instrument. Journal of School Psychology, 44, 427-445. School engagement scales:
pcscencrsm1/2, pcscenfagm1/2, pcscenfslm1/2, pcscenpslm1/2, pcscentsrm1/2, pcscenm1/2
3 School environment 5 PISA - homework

In addition to the 5 items for this measure there is an "opt-out" item for twins to tick in case they are home-educated.		 PISA (OECD Programme for International Student Assessment): www.pisa.oecd.org. TEDS measures were selected from the PISA 2000, 2003 and 2006 student questionnaires. PISA Homework scales:
pchmwkbeht1/2, pchmwkfdbt1/2, pchmwkt1/2
4 School environment 4 PISA - school resources

In addition to the 4 items for this measure there is an "opt-out" item for twins to tick in case they are home-educated.		 PISA (as above) -
5 School environment 3 PISA – attitudes towards subjects PISA (as above) -
6 School environment 4 PISA - attitudes towards school

In addition to the 4 items for this measure there is an "opt-out" item for twins to tick in case they are home-educated.		 PISA (as above) PISA Attitudes Towards School scale: pcatscm1/2
7 Relationships 6 Peer victimization (shortened from 16-item full version).

In addition to the 6 items for this measure there is an "opt-out" item for twins to tick if they prefer not to answer.		 Mynard, H., and Joseph, S. (2000). Development of the Multidimensional Peer-Victimization Scale. Aggressive Behavior, 26, 169-178. Peer Victimisation scale: pcpevit1/2
8 Non-cognitive 8 PISA – maths self-efficacy PISA (as above) PISA maths self-efficacy scale: pcmaset1/2
9 Non-cognitive 3 PISA – maths interest PISA (as above) PISA Maths Interest scale: pcmainm1/2
10 School environment 3 PISA – time spent on maths PISA (as above) PISA Time Spent on Maths scale: pcmatmt1/2
11 Classroom environment 19
  1. Student classroom environment (9 items). Adapted from the full 12-item measure.
  2. PISA – classroom environment (10 items)


In addition to the 19 items for these measures there is an "opt-out" item for twins to tick in case they are home-educated.
  1. Midgley, Eccles and Feldlaufer (1991). Classroom environment and the transition to junior high school. In Fraser and Walberg (eds) Educational environments: Evaluation, Antecedents and Consequences. Oxford: Pergamon Press.
  2. PISA
 -
Environment and Wellbeing Questionnaire part C

(Your Family and Friends, EWQ C)		 2 Home environment and relationships 8 Parental control

In addition to the 8 items for this measure there is an "opt-out" item for twins to tick if they prefer not to answer.		 From NICHD early childcare and youth development study Parental Control scale: pcpacom1/2
3 Home environment and relationships 6 Parental monitoring

In addition to the 6 items for this measure there is an "opt-out" item for twins to tick if they prefer not to answer.		 From NICHD early childcare and youth development study Parental Monitoring scale: pcpamom1/2
4 Home environment and relationships 4 Parental discipline, as used in earlier TEDS studies but reduced to 4 items.

In addition to the 4 items for this measure there is an "opt-out" item for twins to tick if they prefer not to answer.		 Deater-Deckard, K., Dodge, K. A., Bates, J. E., and Pettit, G. S. (1998). Multiple risk factors in the development of externalising behaviour problems: Group and individual differences. Development and Psychopathology, 10, 469 - 493. Parental Discipline scales: pcdisnegt1/2, pcdispost1/2
5 Relationships 25 Inventory of Parent and Peer Attachment. Just the peer attachment was included. We also used the revised version of this scale.

In addition to the 25 items for this measure there is an "opt-out" item for twins to tick if they prefer not to answer.		 Armsden, G. C., and Greenberg, M. T. (1987). The Inventory of Parent and Peer Attachment: Relationships to well-being in adolescence. Journal of Youth and Adolescence, 16 (5), 427-454. Attachment scales:
pcattaalt1/2, pcattacot1/2, pcattatrt1/2, pcattat1/2
Environment and Wellbeing Questionnaire part D

(More About You, EWQ D)		 2 Wellbeing and non-cognitive 13 Grit (items 2, 4-9, 13) and Ambition (items 1, 3, 10, 11, 12) Grit references:
  • Duckworth, A.L, and Quinn, P.D. (2009). Development and validation of the Short Grit Scale (Grit-S). Journal of Personality Assessment, 91, 166-174.
  • Duckworth, A.L., Peterson, C., Matthews, M.D., & Kelly, D.R. (2007). Grit: Perseverance and passion for long-term goals. Journal of Personality and Social Psychology, 9, 1087-1101.
The five Ambition items were apparently also developed by Duckworth but were not published and were not incorporated into the Grit scale as referenced above. Other publications (not by Duckworth) have included the 12 published Grit items and the 5 Ambition items in a 17-item scale but without providing a source reference for the Ambition items. 		Ambition scale and GRIT scales:
pcambim1/2, pcgritcoim1/2, pcgritperm1/2, pcgritm1/2
3 Wellbeing 6 Optimism (LOT-R). Normally 10 items, but for space reasons we have dropped the 4 ‘filler’ items. Scheier, M. F., Carver, C. S., and Bridges, M. W. (1994). Distinguishing optimism from neuroticism (and trait anxiety, self-mastery, and self-esteem): A re-evaluation of the Life Orientation Test. Journal of Personality and Social Psychology, 67, 1063-1078. LOT-R Optimism scale: pclotrm1/2
4 Non-cognitive 11
  1. Academic self-concept (10 items). Shortened from the 20-item scale in Burden (1998).
  2. Self-esteem (1 item). Item added by Yulia Kovas.
 Burden (1998). Assessing children’s perceptions of themselves as learners and problem solvers. School Psychology International, 19(4), 291-305. Academic Self-Concept scale: pcsecom1/2
5 Other 30 Personality

In addition to the 30 items for this measure there is an "opt-out" item for twins to tick if they prefer not to answer.		 Mullins-Sweatt, S. N., Jamerson, J. E., Samuel, D. B., Olson, D. R., Widiger, T. A. (2006). Psychometric Properties of an Abbreviated Instrument of the Five-Factor Model. Assessment, 13: 119-137. Personality subscales:
pcpersagrm1/2, pcpersconm1/2, pcpersextm1/2, pcpersneum1/2, pcpersopem1/2
6, 7, 8 Other 11
  1. Height and weight (2 items)
  2. Puberty: PDS (9 items). This includes 4 general items on screen 6, concluding with a question about twin sex; this is followed by 3 female items on screen 7 for girls, or 2 male items on screen 8 for boys


In addition to the 11 items for these measures, on each screen there is an "opt-out" item for twins to tick if they prefer not to answer.		 Petersen Pubertal Development Scale, Petersen AC, Crockett L, Richards M, Boxer A. A self-report measure of pubertal status: reliability, validity, and initial norms. J Youth Adolesc.1988; 17 :117 –133
  1. Twin BMI, derived from height and weight: pcbmi1/2
  2. Puberty scale: pcpubm1/2, Menstruation onset age: pcqdpub081/2

Behaviour/LEAP/LEAP-2 Study: Child Booklet Measures

The table below refers to pages and items in the Behaviour (wave 1), LEAP (wave 2) and LEAP-2 versions of the twin booklet (pdfs). The "no. of items" column refers to the number of distinct questions in the measure, although some questions have multiple parts leading to a greater number of item variables in the dataset.

Note that the booklet study involved all TEDS cohorts. However, as indicated in the first two columns of the table, certain measures were included in the Behaviour booklet (cohort 1) but not in the LEAP booklet (cohorts 2, 3, 4), or vice versa.

The LEAP-2 booklet also included all cohorts, but for a reduced, selected sample. As shown in column 3 of the table, the measures in LEAP-2 did not always repeated the same measures that were in the Behaviour/LEAP booklets: some new measures were added, and others were dropped.

Behaviour booklet LEAP booklet LEAP-2 booklet No. of items Description of measure References Related scales
page 2 (not included) (not included) 18 SWAN: Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour Scale.

Adapted by Corina and Philip for self-report adolescent sample.		 Swanson, J., Schuck, S., Mann, M., Carlson, C., Hartman, K., Sergeant, J. et al (2005). Categorical and dimensional definitions and evaluations of symptoms of ADHD: The SNAP and the SWAN Ratings Scales [Draft] pcbhswanhypm1/2, pcbhswaninam1/2, pcbhswanm1/2
page 3 page 2 (not included) 4 Subjective Happiness Lyubomirsky, S., and Lepper, H. S. (1999). A measure of subjective happiness: Preliminary reliability and construct validation. Social Indicators Research, 46, 137-155. pcbhshsm1/2
pages 3 to 4 pages 2 to 3 page 3 15 Paranoia subscale of the Specific Psychotic Experiences Questionnaire (SPEQ).

Previously referred to as the Paranoid Checklist measure. 		Ronald, A., Sieradzka, D., Cardno, A. G., Haworth, C. M. A, McGuire, P., Freeman, D. (2014). Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): Findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin, 40, 868-77. Behaviour/LEAP: pcbhprndt1/2
LEAP-2: pcl2prndt1/2
(not included) pages 3, 4, 5, 6
(one item on each page)		 pages 3, 4, 6, 7
(one item on each page)		 4 Distress Adapted by Angelica Ronald from Community Assessment of Psychic Experiences, Stefanis et al (2002). -
(not included) (not included) pages 4 to 5 22 Hypomania Checklist (HCL-16) Forty et al (2010). Reducing the Hypomania Checklist (HCL-32) to a 16-item version. Journal of Affective Disorders, 124: 351-356 pcl2hclhft1/2
page 4 page 3 page 2 10 Hedonia subscale of the Specific Psychotic Experiences Questionnaire (SPEQ).

Previously referred to as Temporal Experience of Pleasure Scale (TEPS) for Hedonia. 		Ronald, A., Sieradzka, D., Cardno, A. G., Haworth, C. M. A, McGuire, P., Freeman, D. (2014). Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): Findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin, 40, 868-77. Behaviour/LEAP: pcbhtepst1/2
LEAP-2: pcl2tepst1/2
page 5 page 4 page 6 13 Short Mood and Feeling Questionnaire (SMFQ) Angold, A., Costello, E. J., Messer, S. C., Pickles, A., Winder, F., and Silver, D. (1995). The development of a short questionnaire for use in epidemiological studies of depression in children and adolescents. International Journal of Methods in Psychiatric Research, 5, 1-12. Behaviour/LEAP: pcbhmfqt1/2
LEAP-2: pcl2mfqt1/2
page 5 page 4 pages 2 to 3 9 Hallucinations subscale of the Specific Psychotic Experiences Questionnaire (SPEQ). Previously referred to as the Cardiff Anomalous Perceptual Scale (CAPS) for Hallucinations.

 Ronald, A., Sieradzka, D., Cardno, A. G., Haworth, C. M. A, McGuire, P., Freeman, D. (2014). Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): Findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin, 40, 868-77. Behaviour/LEAP: pcbhcapst1/2
LEAP-2: pcl2capst1/2
page 6 page 5 pages 6 to 7 8 Grandiosity subscale of the Specific Psychotic Experiences Questionnaire (SPEQ).

Previously referenced as the ‘Myself’ subscale of Cognition Checklist for Mania, Revised for Grandiosity and Peters Delusion Inventory.		 Ronald, A., Sieradzka, D., Cardno, A. G., Haworth, C. M. A, McGuire, P., Freeman, D. (2014). Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): Findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin, 40, 868-77. Behaviour/LEAP: pcbhgrndt1/2
LEAP-2: pcl2grndt1/2
page 6 page 5 page 7 18 Children's Anxiety Sensitivity Index (CASI) Silverman WK, Fleisig W, Rabian B, Peterson RA. Childhood anxiety sensitivity index. J Clin Child Psychol. 1991;20:162-168 Behaviour/LEAP: pcbhcasit1/2
LEAP-2: pcl2casit1/2
(not included) (not included) page 8 12 Highly Sensitive Child (HSC) questionnaire, short form. Pluess, M., Assary, E., Lionetti, F., Lester, K. J., Krapohl, E., Aron, E. N., & Aron, A. (2018). Environmental sensitivity in children: Development of the Highly Sensitive Child Scale and identification of sensitivity groups. Developmental psychology, 54(1), 51. pcl2hsct1/2, pcl2hsceoet1/2, pcl2hscaest1/2, pcl2hsclstt1/2
page 7 page 6 page 9 7 O-LIFE Introvertive Anhedonia for Anhedonia

Shortened from 8 to 7 items.		 Mason, O., Linney, Y., and Claridge, G. (2005). Short scales for measuring schizotypy. Schizophr Res, 78(2-3), 293-296 Behaviour/LEAP: pcbhanhdt1/2
LEAP-2: pcl2anhdt1/2
page 7 page 6 pages 5 to 6 11 O-LIFE Cognitive Disorganisation for cognitive disorganisation.

This is the Cognitive Disorganisation subscale of the Specific Psychotic Experiences Questionnaire (SPEQ).		 Ronald, A., Sieradzka, D., Cardno, A. G., Haworth, C. M. A, McGuire, P., Freeman, D. (2014). Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): Findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin, 40, 868-77. Behaviour/LEAP: pcbhcgdst1/2
LEAP-2: pcl2cgdst1/2
page 8 (not included) (not included) 24 Inventory of Callous-Unemotional Traits (ICUT)
  1. Frick, P.J. (2004). The Inventory of Callous–Unemotional Traits. Unpublished rating scale
  2. Kimonis, E.R., Frick, P.J., et al. (2008) Assessing callous-unemotional traits in adolescent offenders: Validation of the Inventory of Callous Unemotional Traits. Journal of the International Association of Psychiatry and Law
 pcbhicutcalt1/2, pcbhicutunct1/2, pcbhicutunet1/2, pcbhicutt1/2
page 9 pages 6 to 7 (not included) 13 Abbreviated Autism Spectrum Quotient (AQ) Baron-Cohen, S., Wheelwright, S., Skinner, R., Martin, J., and Clubley, E. (2001) The autism-spectrum quotient (AQ): evidence from Asperger syndrome/high-functioning autism, males and females, scientists and mathematicians. J Autism Dev Disord 31(1): 5-17 pcbhaqdett1/2, pcbhaqsoct1/2, pcbhaqt1/2
page 9 page 7 (not included) 6 Brief Multidimensional Students’ Life Satisfaction Scale (BMSLSS) Seligson, J., Huebner, E., & Valois, R. (2003). Preliminary validation of the Brief Multidimensional Students' Life Satisfaction Scale (BMSLSS). Social Indicators Research, 61, 121-145. pcbhlssm1/2
page 10 (not included) (not included) 2 Striking skills and special abilities questions devised by Pedro Vital. Vital, P. M. et al (2009). Relationship between special abilities and autistic-like traits in a large population-based sample of 8-year olds. Journal of Child Psychology and Psychiatry, 50 (9): 1093-1101 -
pages 10 to 11 pages 7 to 8 (not included) 24 Strength and Difficulties Questionnaires (SDQ)

Shortened from 25 to 24 items, as one item is practically duplicated in the MFQ measure. (Note that in the wave 1 booklet, the items are numbered 1 to 25 but item number 17 is omitted. In the wave 2 booklet, the items are numbered 1 to 24.))		 Goodman, R. (1997) The Strengths and Difficulties Questionnaire: A Research Note. Journal of Child Psychology and Psychiatry, 38, 581-586 pcbhsdqemot1/2, pcbhsdqbeht1/2, pcbhsdqcont1/2, pcbhsdqhypt1/2, pcbhsdqpert1/2, pcbhsdqprot1/2
page 11 (not included) (not included) 4 Eating Disorder Diagnostic Scale (EDDS) Stice, E., Fisher, M. and Martinez, E. (2004) Eating Disorder Diagnostic Scale: Additional Evidence of Reliability and Validity. Psychological Assessment, 16 (1): 60-71 pcbheddsm1/2
pages 12 to 13 (not included) (not included) 8 Self Report Delinquency Scale

Reduced to 8 items.		 Elliott, D.S., Huizinga, D. and Ageton, S. (1985) Explaining delinquency and drug use. Sage Publications (Beverly Hills, California) pcbhdlnqt1/2
page 13 (not included) (not included) 5 Mindful Attention Awareness Scale (MAAS).
Shortened from the published 15 items to 5 items for TEDS.		 Brown, K.W. & Ryan, R.M. (2003). The benefits of being present: Mindfulness and its role in psychological well-being. Journal of Personality and Social Psychology, 84, 822-848. pcbhmaast1/2
(not included) page 8 (not included) 1 Gallup Trust measure (wellbeing measure) - -
(not included) page 8 (not included) 5 Meaning in Life measure (wellbeing measure).
5 items from the published 28-item Life Regard Index.		 Battista, J., & Almond, R. (1973). The development of meaning in life. Psychiatry, 36(4), 409-427. pcbhmlifem1/2
(not included) page 9 (not included) 21 Basic Psychological Needs (wellbeing measure). (1) Gagné, M. (2003). The role of autonomy support and autonomy orientation in prosocial behavior engagement. Motivation and Emotion, Vol. 27/3, pp. 199-223.
(2) https://www.oecd.org/skills/piaac/Annex-C-Measures-of-motivation.pdf		 pcbhpneedt1/2, pcbhpneedautt1/2, pcbhpneedcomt1/2, pcbhpneedrelt1/2
(not included) page 10 (not included) 6 Materialistic Values (wellbeing measure).
This is a shortened form of the published Material Values Scale.		 Richins, M. L. (2004). The material values scale: Measurement properties and development of a short form. Journal of consumer Research, 31(1), 209-219 pcbhmvaluem1/2, pcbhmvaluesucm1/2, pcbhmvaluecenm1/2, pcbhmvaluehapm1/2
(not included) pages 10 to 11 (not included) 9 Pittsburgh Sleep Quality Index Buysse DJ, Reynolds CF, Monk TH, Berman SR, Kupfer DJ: The Pittsburgh Sleep Quality Index: A new instrument for psychiatric practice and research. Psychiatry Research 28:193-213, 1989 pcbhsleepdis1/2, pcbhsleepdur1/2, pcbhsleepdys1/2, pcbhsleepeff1/2, pcbhsleeplat1/2, pcbhsleept1/2
(not included) page 11 (not included) 7 Insomnia Severity Index
  1. Bastien, C. H., Vallieres, A., & Morin, C. M. (2001). Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep Medicine, 2, 297-307
  2. Morin, C. M. (1993). Insomnia: psychological assessment and management. New York: Guilford Press
 pcbhinsomt1/2
(not included) (not included) pages 9 to 13 29 PLIKS (psychotic-like symptoms).
This is a shortened form of the published questionnaire, including only the hallucinations and delusions items.		 Adapted from ALSPAC ‘Life of a 16+ Teenager’ questionnaire. See ALSPAC Questionnaires web page.
The source of the ALSPAC questionnaire was Stefanis, N. C. et al (2002): Evidence that three dimensions of psychosis have a distribution in the general population). Psychological Medicine 32(2), 347-58		 pcl2plikt1/2
(not included) pages 11 to 14 pages 13 to 16 26 Alcohol, Tobacco, Cannabis and Drug Use Adapted from ALSPAC ‘Life of a 16+ Teenager’ questionnaire. See ALSPAC Questionnaires web page. pcbhalco21/2, pcl2alco21/2
pages 14 to 15 page 15 pages 8 to 9 20 Life events: reduced Coddington Scale Coddington, R. D. (1972). The significance of life events as etiological factors in the diseases of children: II: a study of a normal population. Journal of Psychosomatic Research, 16, 205-213 Behaviour/LEAP: pcbhlfevnat1/2, pcbhlfevnnt1/2, pcbhlfevpat1/2, pcbhlfevpnt1/2
LEAP-2: pcl2lfevnat1/2, pcl2lfevnnt1/2, pcl2lfevpat1/2, pcl2lfevpnt1/2
page 15 page 16 (not included) 2 Handedness Medland, S.E. et al (2008) Genetic influences on handedness: Data from 25,732 Australian and Dutch twin families. Neuropsychologia, 47: 330-337 -
pages 15 to 16 page 16 (not included) 8
(reduced to 6 items in wave 2)		 Facebook and social networking Items devised by Oliver Davis and Claire Haworth -

Behaviour/LEAP/LEAP-2 Study: Parent Booklet Measures

The table below refers to pages and items in the Behaviour (wave 1), LEAP (wave 2) and LEAP-2 versions of the parent booklet (pdfs). The "no. of items" column refers to the number of distinct questions in the measure; in most cases these are duplicated for the two twins, and some questions have multiple parts leading to several item variables in the dataset.

Note that the booklet study involved all TEDS cohorts. As indicated in the first two columns of the table, the Behaviour booklet (cohort 1) and the LEAP booklet (cohorts 2, 3, 4) included the same measures, with one exception.

The LEAP-2 booklet also included all cohorts, but for a reduced, selected sample. As shown in column 3 of the table, the measures in LEAP-2 did not always repeated the same measures that were in the Behaviour/LEAP booklets: some measures were dropped.

Behaviour booklet LEAP booklet LEAP-2 booklet No. of items Description of measure References Related scales
pages 2 to 3 pages 2 to 3 (not included) 21
  1. Conners: parent rating scale, revised (CPRS-R).
    This 18-item DSM-IV ADHD symptom subscale taken from the revised parent Conners’ rating scale was used as the measure of inattentive and hyperactive-impulsive symptoms.
  2. Parent “Global Index: Emotional Lability” subscale (J-subscale) from the CPRS-R:L [3 items]
 Conners C.K. (2003): Conners’ Rating Scales-Revised: Technical Manual. New York: Multi-Health System Inc. ppbhconnemlt1/2, ppbhconnimpt1/2, ppbhconninat1/2, ppbhconnt1/2
page 4 pages 3 to 4 page 2 10 Scale for the Assessment of Negative Symptoms (SANS).
This is a subscale of the Specific Psychotic Experiences Questionnaire (SPEQ).		 Ronald, A., Sieradzka, D., Cardno, A. G., Haworth, C. M. A, McGuire, P., Freeman, D. (2014). Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): Findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin, 40, 868-77. Behaviour/LEAP: ppbhsansafft1/2, ppbhsansalot1/2, ppbhsansanat1/2, ppbhsansattt1/2, ppbhsansavat1/2, ppbhsanst1/2
LEAP-2: ppl2sansafft1/2, ppl2sansalot1/2, ppl2sansanat1/2, ppl2sansattt1/2, ppl2sansavat1/2, ppl2sanst1/2
page 5 page 4 page 2 2 Relatives with schizophrenia and bipolar disorder Items devised by Geli Ronald and Daniel Freeman -
page 5 pages 4 to 5 page 3 4 Paranoid parenting -
pages 5 to 6 page 5 pages 3 to 4 11 MFQ (Mood and Feelings Questionnaire) Angold, A., Costello, E. J., Messer, S. C., Pickles, A., Winder, F. and Silver, D. (1995). The development of a short questionnaire for use in epidemiological studies of depression in children and adolescents. International Journal of Methods in Psychiatric Research, 5: 1-12 Behaviour/LEAP: ppbhmfqt1/2
LEAP-2: ppl2mfqt1/2
pages 6 to 8 pages 6 to 7 pages 4 to 5 19 Anxiety-Related Behaviours Questionnaire (ARBQ) Eley, T.C., Bolton, D., O’Connor, T.G., Perrin, S., Smith, P. and Plomin, R. (2003). A twin study of anxiety related behaviours in pre-school children. Journal of Child Psychology and Psychiatry, 44: 945 - 960 Behaviour/LEAP: ppbhanxt1/2, ppbhanxshyt1/2, ppbhanxocbt1/2, ppbhanxfeart1/2, ppbhanxnafft1/2, ppbhanxncogt1/2
LEAP-2: ppl2anxt1/2, ppl2anxshyt1/2, ppl2anxocbt1/2, ppl2anxfeart1/2, ppl2anxnafft1/2, ppl2anxncogt1/2
page 8 page 7 (not included) 2 Striking skills and special abilities questions devised by Pedro Vital. Vital, P. M. et al (2009). Relationship between special abilities and autistic-like traits in a large population-based sample of 8-year olds. Journal of Child Psychology and Psychiatry, 50 (9): 1093 -1101 -
pages 9 to 10 pages 8 to 9 (not included) 24 Inventory of Callous-Unemotional Traits Frick, P. J. (2003). The Inventory of Callous-Unemotional Traits. Unpublished rating scale, University of New Orleans ppbhicutcalt1/2, ppbhicutunct1/2, ppbhicutunet1/2, ppbhicutt1/2
pages 11 to 13 pages 9 to 11 (not included) 28 Autism Spectrum Quotient (AQ): abbreviated version, shortened to 28 items Baron-Cohen, S., Wheelwright, S., Skinner, R., Martin, J., Clubley, E. (2001). The autism-spectrum quotient (AQ): evidence from Asperger syndrome/high-functioning autism, males and females, scientists and mathematicians. Journal of Autism and Developmental Disorders 31 (1): 5 -17 ppbhaqatst1/2, ppbhaqdett1/2, ppbhaqimat1/2, ppbhaqsoct1/2, ppbhaqt1/2
pages 13 to 14 pages 12 to 13 pages 5 to 6 17 SDQ (Strengths and Difficulties Questionnaire), shortened from 25 to 17 items Goodman, R. (1997) The Strengths and Difficulties Questionnaire: A Research Note. Journal of Child Psychology and Psychiatry, 38, 581 -586 Behaviour/LEAP: ppbhsdqbeht1/2, ppbhsdqcont1/2, ppbhsdqhypt1/2, ppbhsdqprot1/2
LEAP-2: ppl2sdqbeht1/2, ppl2sdqcont1/2, ppl2sdqhypt1/2, ppl2sdqprot1/2
(not included) page 13 (not included) 3 Asthma Questions devised by ALSPAC -
pages 14 to 16 pages 13 to 15 pages 6 to 7 20 Life events, adapted from Coddington (reduced scale, with 6 positive life events added) Coddington, R. D. (1972). The significance of life events as etiological factors in the diseases of children: II: a study of a normal population. Journal of Psychosomatic Research, 16, 205-213 Behaviour/LEAP: ppbhlfevnat1/2, ppbhlfevnnt1/2, ppbhlfevpat1/2, ppbhlfevpnt1/2
LEAP-2: ppl2lfevnat1/2, ppl2lfevnnt1/2, ppl2lfevpat1/2, ppl2lfevpnt1/2

GCSE Study Measures

The table below refers to the twin GCSE results form (pdf) as used in cohort 2. Note that qualifications in England, Wales and Northern Ireland are subject to frequent changes. Many qualifications described in the links may now differ from those taken in the past by TEDS twins. If you find that any of the links below are broken, please contact TEDS.

Page No. of items Description of measure References Related scales
1 up to 29 GCSE results
(including short-course GCSEs and full GCSEs)

GCSE qualifications are explained on this archived GCSE page of Ofqual (Office of Qualifications and Examination Regulation. This page is linked to a student guide which explains more about grades and assessment.

The awarding bodies also have pages describing their current GCSEs:

 GCSE mean grades, including means in the core subjects: pcexgcsematgrdm1/2, pcexgcseenggrdm1/2, pcexgcsescigrdm1/2, pcexgcsetecgrdm1/2, pcexgcsehumgrdm1/2, pcexgcselangrdm1/2, pcexgcsevocgrdm1/2, pcexgcsegrdm1/2, pcexgcsecoregrdm1/2
GCSE point scores: pcexgcsematpsct1/2, pcexgcseengpsct1/2, pcexgcsescipsct1/2, pcexgcsetecpsct1/2, pcexgcsehumpsct1/2, pcexgcselanpsct1/2, pcexgcsevocpsct1/2, pcexgcsepsct1/2
Numbers of GCSE results: pcexgcsematnum1/2, pcexgcseengnum1/2, pcexgcsescinum1/2, pcexgcsetecnum1/2, pcexgcsehumnum1/2, pcexgcselannum1/2, pcexgcsevocnum1/2, pcexgcsenum1/2
Number of GCSE results at grades A* to C: pcexgcseabcnum1/2
2 up to 3 BTEC, OCR National and City & Guilds qualifications The Ofqual pages preserved in the National Archives web site contain explanations of some of the more common qualification types, including: Other qualification types have their own web sites: All accredited qualification types can be referenced at Ofqual (the register of regulated qualifications). Qualifications other than GCSEs:
Mean grades, including means in the core subjects: pcexothermatgrdm1/2, pcexotherenggrdm1/2, pcexotherscigrdm1/2, pcexothertecgrdm1/2, pcexotherhumgrdm1/2, pcexotherlangrdm1/2, pcexothervocgrdm1/2, pcexothergrdm1/2, pcexothercoregrdm1/2
Point scores: pcexothermatpsct1/2, pcexotherengpsct1/2, pcexotherscipsct1/2, pcexothertecpsct1/2, pcexotherhumpsct1/2, pcexotherlanpsct1/2, pcexothervocpsct1/2, pcexotherpsct1/2
Numbers of results: pcexothermatnum1/2, pcexotherengnum1/2, pcexotherscinum1/2, pcexothertecnum1/2, pcexotherhumnum1/2, pcexotherlannum1/2, pcexothervocnum1/2, pcexothernum1/2

All qualifications, combining GCSE + others:
Mean grades, including means in the core subjects: pcexallmatgrdm1/2, pcexallenggrdm1/2, pcexallscigrdm1/2, pcexalltecgrdm1/2, pcexallhumgrdm1/2, pcexalllangrdm1/2, pcexallvocgrdm1/2, pcexallgrdm1/2, pcexallcoregrdm1/2
Point scores: pcexallmatpsct1/2, pcexallengpsct1/2, pcexallscipsct1/2, pcexalltecpsct1/2, pcexallhumpsct1/2, pcexalllanpsct1/2, pcexallvocpsct1/2, pcexallpsct1/2
Numbers of results: pcexallmatnum1/2, pcexallengnum1/2, pcexallscinum1/2, pcexalltecnum1/2, pcexallhumnum1/2, pcexalllannum1/2, pcexallvocnum1/2, pcexallnum1/2
2 up to 3 Functional Skills, Key Skills, Skills for Life, ALAN and ASDAN
3 1 Digital Applications: AIDA, CIDA and DIDA
3 (open-ended) Any other school qualifications
3 up to 2 AS-levels AS-levels are explained at the Ofqual A and AS levels archive page. -