{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T12:32:26Z","timestamp":1777984346715,"version":"3.51.4"},"update-to":[{"DOI":"10.12688\/wellcomeopenres.25018.1","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2026,4,19]],"date-time":"2026-04-19T00:00:00Z","timestamp":1776556800000}}],"reference-count":3,"publisher":"F1000 Research Ltd","license":[{"start":{"date-parts":[[2026,4,19]],"date-time":"2026-04-19T00:00:00Z","timestamp":1776556800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010269","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["217065"],"award-info":[{"award-number":["217065"]}],"id":[{"id":"10.13039\/100010269","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["wellcomeopenresearch.org"],"crossmark-restriction":false},"short-container-title":["Wellcome Open Res"],"abstract":"<ns3:p>\n                    The Avon Longitudinal Study of Parents and Children (ALSPAC) is an ongoing prospective population-based study that has been running for almost 35 years. Pregnant women with expected dates of delivery falling between 1\n                    <ns3:sup>st<\/ns3:sup>\n                    April 1991 and 31\n                    <ns3:sup>st<\/ns3:sup>\n                    December 1992 were recruited and the health and development of the index children from these pregnancies and that of their family members have been followed ever since. At the time of enrolment, the sampling frame for those eligible to enrol was constructed retrospectively using linked recruitment and health service records. Further explicit recruitment drives took place at the ages of 7 and 18 years to enrol G1 participants (the index children) that were eligible but did not take part originally. These were supplemented by opportunistic contacts from the age of 7 resulting in additional participants being enrolled. Around the age of 30, a further concerted effort was undertaken to encourage unenrolled but eligible participants to take part in the study\u2019s \u2018@30\u2019 clinic. This data note updates the status of recruitment of the index children in 2025, following the completion of the clinic. In total, 1014 additional G1 participants have been enrolled in the study since the age of 7 years, with 101 of these in the most recent phase of recruitment that has taken place since the age of 24. At the time of writing ALSPAC now has a baseline cohort of 15,002 G1 participants alive at 1 year of age.\n                  <\/ns3:p>","DOI":"10.12688\/wellcomeopenres.25018.2","type":"journal-article","created":{"date-parts":[[2026,4,19]],"date-time":"2026-04-19T06:44:06Z","timestamp":1776581046000},"page":"689","update-policy":"https:\/\/doi.org\/10.12688\/wellcomeopenres.crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["The Avon Longitudinal Study of Parents and Children (ALSPAC): an update on the enrolled sample of index children (the G1 cohort) in 2025"],"prefix":"10.12688","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0602-1983","authenticated-orcid":false,"given":"Kate","family":"Northstone","sequence":"first","affiliation":[{"name":"Population Health Sciences Bristol England University of Bristol Medical School"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Brierley","sequence":"additional","affiliation":[{"name":"Population Health Sciences Bristol England University of Bristol Medical School"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2072-3455","authenticated-orcid":false,"given":"Jess","family":"Harvey","sequence":"additional","affiliation":[{"name":"Population Health Sciences Bristol England University of Bristol Medical School"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-0525-1744","authenticated-orcid":false,"given":"Sarah","family":"Matthews","sequence":"additional","affiliation":[{"name":"Population Health Sciences Bristol England University of Bristol Medical School"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7138-9282","authenticated-orcid":false,"given":"Mark","family":"Mumm\u00e9","sequence":"additional","affiliation":[{"name":"Population Health Sciences Bristol England University of Bristol Medical School"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rich","family":"Hobbs","sequence":"additional","affiliation":[{"name":"Population Health Sciences Bristol England University of Bristol Medical School"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"2560","published-online":{"date-parts":[[2026,4,19]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"111-127","DOI":"10.1093\/ije\/dys064","article-title":"Cohort profile: the 'children of the 90s'--the index offspring of the Avon Longitudinal Study of Parents and Children.","volume":"42","author":"A Boyd","year":"2013","journal-title":"Int J Epidemiol."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"97-110","DOI":"10.1093\/ije\/dys066","article-title":"Cohort profile: the Avon Longitudinal Study of Parents and Children: ALSPAC mothers cohort.","volume":"42","author":"A Fraser","year":"2013","journal-title":"Int J Epidemiol."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"51","DOI":"10.12688\/wellcomeopenres.15132.1","article-title":"The Avon Longitudinal Study of Parents and Children (ALSPAC): an update on the enrolled sample of index children in 2019 [version 1; peer review: 2 approved].","volume":"4","author":"K Northstone","year":"2019","journal-title":"Wellcome Open Res."}],"container-title":["Wellcome Open Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2\/iparadigms","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T08:09:09Z","timestamp":1777968549000},"score":1,"resource":{"primary":{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,19]]},"references-count":3,"URL":"https:\/\/doi.org\/10.12688\/wellcomeopenres.25018.2","relation":{"has-version":[{"id-type":"doi","id":"10.12688\/wellcomeopenres.25018.1","asserted-by":"subject"}],"has-review":[{"id-type":"doi","id":"10.21956\/wellcomeopenres.29127.r153639","asserted-by":"subject"},{"id-type":"doi","id":"10.21956\/wellcomeopenres.29127.r153777","asserted-by":"subject"},{"id-type":"doi","id":"10.21956\/wellcomeopenres.29127.r153639","asserted-by":"object"},{"id-type":"doi","id":"10.21956\/wellcomeopenres.29127.r153777","asserted-by":"object"}]},"ISSN":["2398-502X"],"issn-type":[{"value":"2398-502X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,19]]},"assertion":[{"value":"Indexed","URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2#article-reports","order":0,"name":"referee-status","label":"Referee status","group":{"name":"current-referee-status","label":"Current Referee Status"}},{"value":"10.21956\/wellcomeopenres.29127.r153639, Gillian Santorelli, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, England, 23 Apr 2026, version 2, indexed","URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2#referee-response-153639","order":0,"name":"referee-response-153639","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.21956\/wellcomeopenres.27564.r149451, Abdul Wajid, University of Calgary, Calgary, Alberta, 25 Mar 2026, version 1, 2 approved with reservations","URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v1#referee-response-149451","order":1,"name":"referee-response-149451","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Kate Northstone<\/b>; \n<i>Posted: 07 Apr 2026<\/i>; Thank you so much for your helpful comments. We repat your comments below and add our response in bold: &nbsp;  1. For phase V recruitment, the authors mention age range as 24, up to and including 30-year. As the original recruitment for this cohort was started in 1991\/92 with some even delivered moms. By 2024 the age of a G1 participant (an index child) could go beyond 30 years, up to 32 years. Unless, there was an explicit reason for not to recruit participants beyond 30 years, the statement should not restrict at 30 years but should clearly indicate beyond 30 year. Interestingly, the Figure 1 shows age range for phase V as 24-30+.&nbsp;  \n<b>Thank you for this comment. You are correct that the participants could be older than 30 at the time of phase V recruitment. However, we are referring to the specific data collection points. The @30 clinic was the key driver for phase V recruitment and that is why we refer to 30+, as new &nbsp;participants could indeed be older than 30 when they enrolled. We have added a sentence to the end of the introduction which clarifies this.<\/b>  2. For phase V recruitment, three routes were chosen; however, only re-engagement packs, the route 1, participants were provided with monetary incentive. Was there a specific reason for not incentivizing other two groups and only providing incentives to this group?  \n<b>We did not have ethical approval to incentivise the other two groups and as they approached us voluntary for both of these routes we did not feel an incentive was necessary.<\/b>","URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2#referee-comment-6505","order":2,"name":"referee-comment-6505","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.21956\/wellcomeopenres.29127.r153777, Sivenesi Subramoney, University of California Merced, Merced, California, 05 May 2026, version 2, indexed","URL":"https:\/\/wellcomeopenresearch.org\/articles\/10-689\/v2#referee-response-153777","order":3,"name":"referee-response-153777","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"This work was supported by Wellcome [217065,102215 and 086118]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.","order":4,"name":"grant-information","label":"Grant Information"},{"value":"This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.","order":0,"name":"copyright-info","label":"Copyright"}]}}