Avon Longitudinal Study of Parents and Children
The original aim of ALSPAC was to determine which biological, environmental, social, psychological and psychosocial factors are associated with the survival and optimal health and development of the fetus, infant and child, and the ways in which causal relationships might vary with the genetic composition of mother and/or child.
To identify the complex ways in which environmental features may be associated with the optimal development, health and well-being of the child, will involve a study of the ways in which genes and the environment interact. A child's ability to meet environmental and social challenges is influenced by genetic variation, but the interactions are complex. Genetic susceptibility or resistance to common disorders is likely to be bestowed by one or more genetic polymorphisms, the impact of which will change as various environmental and developmental stresses on the child change. ALSPAC was specifically designed to analyse this interplay between genes and environment with respect to important relatively common health outcomes.
Overview
- Acronym
- ALSPAC
- Website
- ALSPAC
- Investigators
-
- Contacts
-
General Design
- Study design
- Cohort
- Start - End Year
- 1990 -
- General Information on Follow Up (profile, frequency)
-
During the index pregnancy, most women were sent 3 questionnaires. Since then, over a period of some 25 years, women have been sent 22 additional questionnaires that refer to their own health and well-being. Since 2008, women have attended four focus clinical ssessments
Assessments of the children have been administered frequently, with 64 data collection time points between birth and 24 years of age. These include 34 child-completed questionnaires, 20 focus clinical assessments and 23 questionnaires about the child completed by the mother or other main caregiver.
Partners have been sent 17 questionnaires and have attended 1 focus clinic assessment.
Siblings and grandparents have been recruited.
- Recruitment Target
-
- Families
- Number of Participants
- 42,710
- Number of Participants with Biological Samples
- 22,000 (No Limit)
- Supplementary information about number of participants
-
ALSPAC recruited 14,541 pregnant women resident in Avon, UK with expected dates of delivery 1st April 1991 to 31st December 1992. 14,541 is the initial number of pregnancies for which the mother enrolled in the ALSPAC study and had either returned at least one questionnaire or attended a “Children in Focus” clinic by 19/07/99. Of these initial pregnancies, there was a total of 14,676 fetuses, resulting in 14,062 live births and 13,988 children who were alive at 1 year of age.
When the oldest children were approximately 7 years of age, an attempt was made to bolster the initial sample with eligible cases who had failed to join the study originally. As a result, when considering variables collected from the age of seven onwards (and potentially abstracted from obstetric notes) there are data available for more than the 14,541 pregnancies mentioned above.
The number of new pregnancies not in the initial sample (known as Phase I enrolment) that are currently represented on the built files and reflecting enrolment status at the age of 18 is 706 (452 and 254 recruited during Phases II and III respectively), resulting in an additional 713 children being enrolled. The phases of enrolment are described in more detail in the cohort profile paper which should be used for referencing purposes: <http://ije.oxfordjournals.org/content/early/2012/04/14/ije.dys064.full.pdf+html>.
The total sample size for analyses using any data collected after the age of seven is therefore 15,247 pregnancies, resulting in 15,458 fetuses. Of this total sample of 15,458 fetuses, 14,775 were live births and 14,701 were alive at 1 year of age.
A 10% sample of the ALSPAC cohort, known as the Children in Focus (CiF) group, attended clinics at the University of Bristol at various time intervals between 4 to 61 months of age. The CiF group were chosen at random from the last 6 months of ALSPAC births (1432 families attended at least one clinic). Excluded were those mothers who had moved out of the area or were lost to follow-up, and those partaking in another study of infant development in Avon.
Access
Availability of data and biosamples
| Possible Access to Data | |
| Possible Access to Biosamples | |
| Other |
|
Marker Paper
Boyd A., Golding J., Macleod J., Lawlor D.A., Fraser A., Henderson J., Molloy L., Ness A., Ring S., Davey Smith G. Cohort Profile: The ‘Children of the 90s’—the index offspring of the Avon Longitudinal Study of Parents and Children. International Journal of Epidemiology 2012;1-17
PUBMED 22507743Timeline
Populations
The population consists of all pregnant women residents in the old administrative county of Avon, in the South West of England, with an expected date of delivery between 1 April 1991 and 31 December 1992.
Selection Criteria
- Gender
-
Women only
- Pregnant Women
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- First trimester
- Second trimester
- Third trimester
- Countries
-
- United Kingdom
- Territory
-
Old administrative county of Avon, South West England.
Sources of Recruitment
- General Population
-
- Volunteer enrolment
- Specific Population
-
- Clinic patients
- Supplementary Information
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ALSPAC attempted to make contact with eligible women through media information encouraging study contact and recruitment staff visiting community locations. In parallel, routine antenatal and maternity health services were used to promote the study and distribute an ‘expression of interest’ card. Through returning this card, women were able to request further information on the study or to decline participation. Completed cards contained sufficient detail to allow ALSPAC staff to determine eligibility.
Posters were printed for display in a variety of different places - including chemist shops, libraries, mother and toddler groups, and pre-school playgroups, general practitioner waiting-rooms, antenatal clinics and any other area where a mother in early pregnancy was likely to be. In addition, there was considerable local and national coverage in the press, radio and television.
Sample Size
- Number of Participants
- 14,541
- Number of Participants with Biological Samples
- 10,000 (No Limit)
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | ALSPAC - Mothers - Biosample collection 1990 to 1992 |
|
|
1990 (July) | 1992 (March) |
| 1 | ALSPAC - Mothers - 8 to 42 weeks gestation |
|
1990 (September) | 1992 (October) | |
| 2 | ALSPAC - Mothers - 18 weeks gestation |
|
1990 (November) | 1992 (September) | |
| 3 | ALSPAC - Mothers - 12 weeks gestation |
|
1990 (November) | 1993 (August) | |
| 4 | ALSPAC - Mothers - 32 weeks gestation |
|
1991 (March) | 1993 (January) | |
| 5 | ALSPAC - Mothers - 8 weeks |
|
1991 (May) | 1993 (April) | |
| 6 | ALSPAC - Mothers - 8 months |
|
1992 (April) | 1993 (October) | |
| 7 | ALSPAC - Mothers - 21 months |
|
1992 (September) | 1994 (November) | |
| 8 | ALSPAC - Mothers - 33 months |
|
1993 (October) | 1995 (November) | |
| 9 | ALSPAC - Mothers - Biosample collection 1993 |
|
|
1993 (November) | 1993 (November) |
| 10 | ALSPAC - Mothers - 47 months |
|
1994 (November) | 1997 (January) | |
| 11 | ALSPAC - Mothers - 61 months |
|
1996 (January) | 1998 (March) | |
| 12 | ALSPAC - Mothers - 73 months |
|
1997 (February) | 1999 (March) | |
| 13 | ALSPAC - Mothers - 85 months |
|
1998 (August) | 2000 (March) | |
| 14 | ALSPAC - Mothers - 97 months |
|
1999 (September) | 2001 (May) | |
| 15 | ALSPAC - Mothers - 110 months |
|
2000 (October) | 2002 (April) | |
| 16 | ALSPAC - Mothers - 122 months |
|
2001 (August) | 2003 (April) | |
| 17 | ALSPAC - Mothers - 134 months |
|
2002 (July) | 2004 (May) | |
| 18 | ALSPAC - Mothers - 145 months |
|
2003 (May) | 2005 (May) | |
| 19 | ALSPAC - Mothers - Biosample collection 2004 to 2008 |
|
|
2004 | 2008 |
| 20 | ALSPAC - Mothers - 156 months |
|
2004 (May) | 2004 (October) | |
| 21 | ALSPAC - Mothers - Focus on mothers 1 |
|
|
2008 (December) | 2011 (July) |
| 22 | ALSPAC - Mothers - 18 years |
|
2009 (May) | 2010 (September) | |
| 23 | ALSPAC - Mothers - Focus on mothers 2 |
|
|
2011 (July) | 2013 (June) |
| 24 | ALSPAC - Mothers - 20 years |
|
2011 (September) | 2012 (February) | |
| 25 | ALSPAC - Mothers - 22 years |
|
2012 (September) | 2014 (December) | |
| 26 | ALSPAC - Mothers - Focus on mothers 3 |
|
|
2013 (March) | 2014 (March) |
| 27 | ALSPAC - Mothers - Focus on mothers 4 |
|
|
2014 (April) | 2015 (March) |
The population consists of partners; whether it is the biological fathers or those who take on the role of a parent of the children enrolled in the study.
Selection Criteria
- Countries
-
- United Kingdom
- Territory
-
Old administrative county of Avon.
Sources of Recruitment
- Specific Population
-
-
Other specific population :
Mothers’ partners or fathers of the children recruited in ALSPAC.
-
Other specific population :
Sample Size
- Number of Participants
- 10,207
- Number of Participants with Biological Samples
- 1,000
- Supplementary Information about selection criteria
-
Partners of the mothers were invited to complete self completion questionnaires from pregnancy onwards by the mother.
Fathers were then enrolled into the study in their own right - 3000 were enrolled in 2010 and were invited to attend a hands-on clinical assessment and complete further questionnaries.
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | ALSPAC - Partners - 18 weeks gestation |
|
1990 (November) | 1992 (September) | |
| 1 | ALSPAC - Partners - 12 weeks gestation |
|
1990 (November) | 1993 (August) | |
| 2 | ALSPAC - Partners - 8 weeks |
|
1991 (May) | 1993 (April) | |
| 3 | ALSPAC - Partners - 8 months |
|
1992 (April) | 1993 (October) | |
| 4 | ALSPAC - Partners - 21 months |
|
1992 (September) | 1994 (November) | |
| 5 | ALSPAC - Partners - 33 months |
|
1993 (October) | 1995 (November) | |
| 6 | ALSPAC - Partners - Biosample collection 1993 |
|
|
1993 (November) | 1993 (November) |
| 7 | ALSPAC - Partners - 47 months |
|
1994 (November) | 1997 (January) | |
| 8 | ALSPAC - Partners - 61 months |
|
1996 (January) | 1998 (March) | |
| 9 | ALSPAC - Partners - 73 months |
|
1997 (February) | 1999 (March) | |
| 10 | ALSPAC - Partners - 85 months |
|
1998 (August) | 2000 (March) | |
| 11 | ALSPAC - Partners - 97 months |
|
1999 (September) | 2001 (May) | |
| 12 | ALSPAC - Partners - 110 months |
|
2000 (October) | 2002 (April) | |
| 13 | ALSPAC - Partners - 122 months |
|
2001 (August) | 2003 (April) | |
| 14 | ALSPAC - Partners - 134 months |
|
2002 (July) | 2004 (May) | |
| 15 | ALSPAC - Partners - 145 months |
|
2003 (May) | 2005 (May) | |
| 16 | ALSPAC - Partners - Biosample collection 2004-2008 |
|
|
2004 (January) | 2008 (December) |
| 17 | ALSPAC - Partners - 156 months |
|
2004 (May) | 2004 (October) | |
| 18 | ALSPAC - Partners - Biosample collection 2010 |
|
|
2010 (May) | 2010 (May) |
| 19 | ALSPAC - Partners - 20 years |
|
2011 (January) | 2012 (December) | |
| 20 | ALSPAC - Partners - 21/22 years |
|
2011 (September) | 2013 (February) | |
| 21 | ALSPAC - Partners - Focus on father 1 |
|
2011 (September) | 2013 (February) |
The population consists of any resulting child from all pregnant women residents in the old administrative county of Avon if their estimated delivery date fell between 1 April 1991 and 31 December 1992.
Selection Criteria
- Newborns
- Countries
-
- United Kingdom
- Territory
-
Old administrative county of Avon, South West England.
Sources of Recruitment
- Specific Population
-
-
Other specific population :
Children of the mothers recruited in ALSPAC.
-
Other specific population :
Sample Size
- Number of Participants
- 14,062
- Number of Participants with Biological Samples
- 10,000 (No Limit)
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | ALSPAC - Children - Biosample collection birth |
|
|
1991 (April) | 1992 (December) |
| 1 | ALSPAC - Children - 4 weeks |
|
1991 (April) | 1993 (April) | |
| 2 | ALSPAC - Children - 6 months |
|
1991 (July) | 1993 (August) | |
| 3 | ALSPAC - Children - Biosample collection 6 to 18 months |
|
|
1991 (October) | 1994 (June) |
| 4 | ALSPAC - Children - 15 months |
|
1992 (August) | 1994 (May) | |
| 5 | ALSPAC - Children - Children in focus 4 months |
|
1992 (October) | 1993 (April) | |
| 6 | ALSPAC - Children - 18 months |
|
1992 (October) | 1994 (August) | |
| 7 | ALSPAC - Children - 24 months |
|
1993 (January) | 1995 (February) | |
| 8 | ALSPAC - Children - Children in focus 8 months |
|
1993 (February) | 1993 (August) | |
| 9 | ALSPAC - Children - Children in focus 12 months |
|
|
1993 (June) | 1993 (December) |
| 10 | ALSPAC - Children - Children in focus 18 months |
|
|
1993 (December) | 1994 (June) |
| 11 | ALSPAC - Children - 30 months |
|
1994 (January) | 1995 (August) | |
| 12 | ALSPAC - Children - 38 months |
|
1994 (March) | 1996 (April) | |
| 13 | ALSPAC - Children - Biosample collection 3 years |
|
|
1994 (April) | 1995 (December) |
| 14 | ALSPAC - Children - Children in focus 25 months |
|
1994 (July) | 1995 (January) | |
| 15 | ALSPAC - Children - 42 months |
|
1994 (July) | 1996 (October) | |
| 16 | ALSPAC - Children - Children in focus 31 months |
|
|
1995 (January) | 1995 (July) |
| 17 | ALSPAC - Children - Biosample collection 4 years |
|
|
1995 (April) | 1996 (December) |
| 18 | ALSPAC - Children - Children in focus 37 months |
|
1995 (July) | 1996 (January) | |
| 19 | ALSPAC - Children - 54 months |
|
1995 (July) | 1997 (August) | |
| 20 | ALSPAC - Children - Children in focus 43 months |
|
|
1996 (January) | 1996 (July) |
| 21 | ALSPAC - Children - 57 months |
|
1996 (January) | 1997 (November) | |
| 22 | ALSPAC - Children - Biosample collection 5 to 7 years |
|
|
1996 (April) | 1999 (December) |
| 23 | ALSPAC - Children - Children in focus 49 months |
|
1996 (July) | 1997 (January) | |
| 24 | ALSPAC - Children - 65 months |
|
1996 (October) | 1998 (July) | |
| 25 | ALSPAC - Children - 69 months |
|
1997 (February) | 1998 (December) | |
| 26 | ALSPAC - Children - 73 months |
|
1997 (February) | 1999 (March) | |
| 27 | ALSPAC - Children - Children in focus 61 months |
|
|
1997 (July) | 1998 (April) |
| 28 | ALSPAC - Children - 77 months |
|
1997 (November) | 1999 (July) | |
| 29 | ALSPAC - Children - 81 months |
|
1998 (March) | 1999 (November) | |
| 30 | ALSPAC - Children - Biosample collection 7 to 8 years |
|
|
1998 (April) | 2000 (December) |
| 31 | ALSPAC - Children - 91 months |
|
1998 (July) | 2000 (October) | |
| 32 | ALSPAC - Children - 85 months |
|
1998 (August) | 2000 (March) | |
| 33 | ALSPAC - Children - Children in focus 7 years |
|
|
1998 (September) | 2000 (September) |
| 34 | ALSPAC - Children - 97 months |
|
1999 (September) | 2001 (May) | |
| 35 | ALSPAC - Children - Children in focus 8 years |
|
1999 (October) | 2001 (December) | |
| 36 | ALSPAC - Children - 103 months |
|
2000 (May) | 2001 (September) | |
| 37 | ALSPAC - Children - 110 months |
|
2000 (October) | 2002 (April) | |
| 38 | ALSPAC - Children - Children in focus 9 years |
|
|
2001 (January) | 2003 (January) |
| 39 | ALSPAC - Children - 115 months |
|
2001 (February) | 2002 (November) | |
| 40 | ALSPAC - Children - 122 months |
|
2001 (November) | 2003 (April) | |
| 41 | ALSPAC - Children - Children in focus 10 years |
|
|
2002 (February) | 2003 (October) |
| 42 | ALSPAC - Children - 128 months |
|
2002 (February) | 2003 (November) | |
| 43 | ALSPAC - Children - 134 months |
|
2002 (July) | 2004 (May) | |
| 44 | ALSPAC - Children - 140 months |
|
2002 (December) | 2004 (November) | |
| 45 | ALSPAC - Children - Children in focus 11 years |
|
|
2003 (January) | 2005 (January) |
| 46 | ALSPAC - Children - 145 months |
|
2003 (May) | 2005 (May) | |
| 47 | ALSPAC - Children - Teen in focus 12 years |
|
|
2004 (February) | 2005 (November) |
| 48 | ALSPAC - Children - 157 months |
|
2004 (May) | 2006 (April) | |
| 49 | ALSPAC - Children - Teen in focus 13 years |
|
|
2005 (January) | 2006 (September) |
| 50 | ALSPAC - Children - 166 months |
|
2005 (July) | 2006 (December) | |
| 51 | ALSPAC - Children - 167 months |
|
2005 (September) | 2007 (January) | |
| 52 | ALSPAC - Children - 169 months |
|
2006 (January) | 2007 (March) | |
| 53 | ALSPAC - Children - Teen in focus 15 years |
|
|
2006 (October) | 2008 (November) |
| 54 | ALSPAC - Children - 192 months |
|
2007 (March) | 2009 (February) | |
| 55 | ALSPAC - Children - Biosample collection 17 years |
|
|
2008 (April) | 2009 (December) |
| 56 | ALSPAC - Children - 17 years |
|
2008 (April) | 2010 (December) | |
| 57 | ALSPAC - Children - 198 months |
|
2008 (October) | 2009 (September) | |
| 58 | ALSPAC - Children - Teen in focus 17 years |
|
|
2008 (December) | 2011 (June) |
| 59 | ALSPAC - Children - 18 years |
|
2010 (September) | 2011 (May) | |
| 60 | ALSPAC - Children - Biosample collection 21 to 22 years |
|
|
2012 (April) | 2014 (December) |
| 61 | ALSPAC - Children - 20 years |
|
2012 (September) | 2013 (July) | |
| 62 | ALSPAC - Children - 21 years |
|
2013 (December) | 2014 (October) | |
| 63 | ALSPAC - Children - 22 years |
|
2014 (November) | 2015 (October) | |
| 64 | ALSPAC - Children - Biosample collection 24 to 25 years |
|
|
2015 (April) | 2017 (December) |
| 65 | ALSPAC - Children - Children in focus 24 years |
|
|
2015 (June) | 2017 (September) |
| 66 | ALSPAC - Children - 23 years |
|
2015 (December) | 2016 (September) | |
| 67 | ALSPAC - Children - 24 years |
|
2016 (November) | 2017 (August) | |
| 68 | ALSPAC - Children - 25 years |
|
2017 (November) | 2018 (July) | |
| 69 | ALSPAC - Children - 26 years |
|
2018 (November) | 2019 (September) |
The population consists of the children of the children enrolled in the first generation of the study.
Selection Criteria
- Countries
-
- United Kingdom
- Territory
-
Old administrative county of Avon.
Sources of Recruitment
- Specific Population
-
-
Other specific population :
Children of the children recruited in ALSPAC.
-
Other specific population :
Sample Size
- Number of Participants
- 1,100
- Number of Participants with Biological Samples
- 1,000
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | ALSPAC - Generation 2 - Birth |
|
|
2012 | 2019 |
| 1 | ALSPAC - Generation 2 - 7 to 15 days |
|
|
2012 | 2019 |
| 2 | ALSPAC - Generation 2 - 6 months |
|
|
2012 | 2019 |
| 3 | ALSPAC - Generation 2 - 12 months |
|
|
2013 | 2019 |
| 4 | ALSPAC - Generation 2 - 24 months |
|
2014 | 2019 | |
| 5 | ALSPAC - Generation 2 - 36 months |
|
|
2015 | 2019 |
| 6 | ALSPAC - Generation 2 - 48 months |
|
2016 | 2019 | |
| 7 | ALSPAC - Generation 2 - 60 months |
|
|
2017 | 2019 |
| 8 | ALSPAC - Generation 2 - 72 months |
|
|
2018 | 2019 |
| 9 | ALSPAC - Generation 2 - 84 months |
|
2019 | 2019 |
The population consists of the siblings of the children enrolled in the ALSPAC study .
Selection Criteria
- Countries
-
- United Kingdom
- Territory
-
Old administrative county of Avon.
Sources of Recruitment
- Specific Population
-
-
Other specific population :
Siblings of the children recruited in ALSPAC.
-
Other specific population :
Sample Size
- Number of Participants
- 1,800 (No Limit)
- Supplementary Information about selection criteria
-
Initial target is 1800 (but not limited to this)
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | ALSPAC - Siblings - Recruitment |
|
|
2014 | 2015 |
The population consists of the grandparents of the children enrolled in the ALSPAC study.
Selection Criteria
- Countries
-
- United Kingdom
- Territory
-
Old administrative county of Avon.
Sources of Recruitment
- Specific Population
-
-
Other specific population :
Grandparents of the children recruited in ALSPAC.
-
Other specific population :
Sample Size
- Number of Participants
- 1,000
- Supplementary Information about selection criteria
-
Initital target for einrollment is 1000 (but not limited to this)
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | ALSPAC - Grandparents - Recruitment |
|
|
2014 (September) | 2015 |
Participating Studies
| Acronym | Name | Study design | Countries |
|---|
Harmonization Initiatives Included
| Acronym | Name |
|---|
Datasets
| Name | Data Collection Events | Variables |
|---|
Areas of Information Collected
- Socio-demographic and economic characteristics
- Death
- Lifestyle and behaviours
- Physical measures and assessments
- Birth, pregnancy and reproductive health history
- Laboratory measures
- Perception of health, quality of life, development and functional limitations
- Cognition, personality and psychological measures and assessments
- Diseases
- Life events, life plans, beliefs and values
- Symptoms and signs
- Preschool, school and work life
- Medication and supplements
- Social environment and relationships
- Non-pharmacological interventions
- Physical environment
- Health and community care services utilization
- Administrative information
Variables Content Summary
Areas of Information Collected
Areas of Information Collected per per Population and Data Collection Event
Networks
| Acronym | Name | Harmonization Initiatives | Individual Studies |
|---|