Search for variables collected in the ALSPAC study

App version: 0.2.3 (11 February 2024)
Data version: 0.46.0

The ALSPAC data resource

The Avon Longitudinal Study of Parents and Children (ALSPAC), also known as Children of the 90s, is a world-leading birth cohort study, charting the health of 14,500 families in the Bristol area. You can find full information about the cohort here

For more than two decades clinic and questionnaire data has been collected from the participants.

This search tool is a quick and abridged version of a much more extensive data dictionary. You can find a lot more detail about these data here

The variable search tool

Use this website to search through the variables, obtain their identifiers and the number of records with that measure

You can use download lists of selected variables. For direct users, this can be used to extract variables directly. Alternatively, add this list to your data request form to specify the data that you require.



  1. G1 (YPL) files (Life@30 Winter 2022 Questionnaire)
  • YPL data filename: YPL_1a in R:\Data\Current\Quest\Child Completed
  • YPL data documentation: D1498_YPL in R:\Data\documentation\built_pdf\Quest\Child Completed


  1. First version release of G0 Mothers (MA) and Partners (FPE) files (Parents Summer 2022 Questionnaire)
  • MA data filename: MA_1a in R:\Data\Current\Quest\Mother
  • MA data documentation: D1194_MA in R:\Data\documentation\built_pdf\Quest\Mother
  • FPE data filename: FPE_1a in R:\Data\Current\Quest\Partner
  • FPE data documentation: D1295_FPE in R:\Data\documentation\built_pdf\Quest\Partner


  1. Updated version release of G0 Mothers (Z) - Parents Questionnaire 2022

Changes - correction to mult-mum cases included and cohort case selection criteria

  • Z data filename: Z_1b in R:\Data\Current\Quest\Mother
  • Z data documentation: D1196_Z.pdf in R:\Data\documentation\built_pdf\Quest\Mother


  1. G0 Partners (FD) files (Parents 2022 Questionnaire)
  • FD data filename: FD_1a in R:\Data\Current\Quest\Partner
  • FD data documentation: D1297_FD in R:\Data\documentation\built_pdf\Quest\Partner


  1. First version release of G0 Mothers (Z) and Partners (FD) files (Parents 2022 Questionnaire)
  • Z data filename: Z_1a in R:\Data\Current\Quest\Mother
  • Z data documentation: D1196_Z in R:\Data\documentation\built_pdf\Quest\Mother
  • FD data filename: FD_1a in R:\Data\Current\Quest\Partner
  • FD data documentation: D1297_FD in R:\Data\documentation\built_pdf\Quest\Partner
  1. Documentation only update to G0 MZ Cohort Profile – addition of the weblink for the published data note
  • G0 MZ data documentation: D4101_MZ in R:\Data\documentation\built_pdf\Other\Cohort Profile
  1. Documentation only update to G1 KL data file (Development & Health of my Sons/Daughters).

Contents page updated with explanation of legacy issue regarding error in formatted page numbers

  • KL data documentation: D1310_KL in R:\Data\documentation\built_pdf\Quest\Child Based


  1. First version release of G1 YPK file (Summer 2022 Questionnaire)
  • YPK data filename: YPK_1a in R:\Data\Current\Quest\Child Completed
  • YPK data documentation: D1493_YPK in R:\Data\documentation\built_pdf\Quest\Child Completed
  1. Documentation only update to G1 F07 (Focus at 7 Clinic) – correction of error in documentation text with reference to

Energy intake derived variables, ff7dd400 to f7dd404.

  • Incorrectly stated f7dd408 to f7dd412.
  • F07 data documentation: D2102_F07 in R:\Data\documentation\built_pdf\Clinic\Child
  1. Variable label correction to YPF8280 in G1 YPF data file (Life at 26).

Incorrectly labelled as j3b instead of j3a, data file and documentation corrected.

  • YPF data filename: YPF_3b in R:\Data\Current\Quest\Child Completed
  • YPF data documentation: D1430_YPF in R:\Data\documentation\built_pdf\Quest\Child Completed
  1. Erroneous variable removed from FOM2 (Focus on Mothers Clinic 2) data file along with documentation update to incorrect text reference for pQCT variables

Fm1a011 erroneously included (from FOM1 clinic) in FOM2 data file. Text in documentation incorrectly referred to FOM1 hip dxa data in the pQCT derived variable section. The DV’s (fm2pq013a to fm2pq280b) are derived from fm2pq007 to fm2pq012.

  • FOM2 data filename: FOM2_5b in R:\Data\Current\Clinic\Adult
  • FOM2 data documentation: D2202_FOM2 in R:\Data\documentation\built_pdf\Clinic\Mother


We are pleased to announce that the following new data is now available on general release:

  1. Updated derived G1 MRI scan data
  • MRI _YP data filename: MRI_YP_2b in R:\Data\Current\Other\Longitudinal
  • MRI _YP data documentation: D2434_MRI_YP in R:\Data\documentation\built_pdf\Other\Longitudinal
  1. Addition of section H question H1 and derived variables – YPH file (Life@28+)

Mental health treatment derived data: antidepessant/antipsychotic/anxiolytic medications and medication behaviours.

  • YPH data filename: YPH_2a in R:\Data\Current\Quest\Child Completed
  • YPH data documentation: D1491_YPH in R:\Data\documentation\built_pdf\Quest\Child Completed
  1. First version release of YPJ file (Life@29+)
  • YPJ data filename: YPJ_1a in R:\Data\Current\Quest\Child Completed
  • YPJ data documentation: D1440_YPJ in R:\Data\documentation\built_pdf\Quest\Child Completed
  1. Removal of mult_mum variables from the following files: V, Y, COVID1-6, SERO, SERO2, FOM2-4.

The mult_mum variable is used to detect those mothers who have had multiple G1 pregnancies. This variable is now located within the mothers cohort profile file (MZ).



  • Derived data collected from MRI scans taken at ALSPAC Neuroimaging Sub Studies (861 subjects, 495 variables).


  • Enrolment information and basic data on all eligible ALSPAC pregnancies (36 variables).


  • Data collected from the second serology test (16 variables).


  • correction to the IL6 data to reflect two types taken from 9yr samples.

COVID5_YP_2a, COVID5_Mum_2a and COVID5_G0Partner_2a

  • Updates to Yes/No labels and lower cutpoints added for EPDS and SMF scores for men.



  • This is the latest set of questions relating to COVID for G0 and G1 participants collected during 29th April-12th May 2022. This questionnaire was available in online format only. It was one part of a triple data collection along with a second round of antibody testing and CAMCOG cognitive testing – results for both will be announced separately.



  • This is the latest set of questions relating to COVID for G0 and G1 participants collected during July-December 2021.


Child-based Deprivation Indices & urban/rural status

  • January timepoints 2015-2021, collection timepoints for: F24, TD, TE, CCXE, CCXF, YPA, YPB, YPC, YPD, YPE, YPF, COVID1, COVID2, COVID3, and IMD2015 tied to all timepoints.

Serology 2 dataset


COVID questionnaire data now available

  • COVID1_Mum_1a - D1171_COVID1_G0Mum - The G0 mother’s COVID1 questionnaire data (457 variables)
  • COVID1_G0partner_1a - D1270_COVID1_G0Dad - The G0 partner/father’s COVID1 questionnaire data (457 variables).
  • COVID1_YP_1a - D1472_COVID1_YP - The G1 YP’s COVID1 questionnaire data (459 variables).
  • COVID1_YPpartner_1a - D1473_COVID1_YPP - The G1 YP’s partner’s COVID1 questionnaire data (459 variables). Note that this dataset is not openly available due to low n, but researchers can request it - Please contact ALSPAC if you are interested in using this data.


Updates have been made to the following variable collections

  • j_5a
  • CCT_1b
  • T_1c
  • n_r1b
  • h_6d
  • ta_2a
  • tc_2a


Updates have been made to the following variable collections

  • Child_bloods_r3a
  • FOM4_2a
  • Father_metabolomics_1a
  • mum_metabolomics_2a


Updates have been made to the following variable collections

  • Focus@7
  • Focus@8
  • Focus@9
  • Focus 10
  • Focus 11



  • New web application for searching through the ALSPAC phenotype collection

Freely browse available ALSPAC data by variable name


Use the search box to filter on keywords or terms. Click on rows to select those variables. Click the Download button to download a csv of the variables that you have selected.

If there is anything you cannot find, please consult the data dictionary or variables catalog . You can also get help from the team at .

Note: Sometimes the sample counts presented here will be inaccurate - consult the data dictionary data dictionary for accurate summary data for each of the variables

Note: High dimensional biological data including genetic variants, DNA methylation measures and gene expression measures are not included in this tool. You can find out more about sample availability here

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