Québec Longitudinal Study of Child Development
The Quebec Longitudinal Study of Child Development (QLSCD) was set up in the end of the 1990s. About 20 years later, a second study was set up.
The general objective of the QLSCD 1st edition - Cohort 1996 (*In 2001, I was 5 years old*) is to better understand the link between the development of the child and their adaptation upon entering school.
The initial main objective of the QLSCD 1st edition - Cohort 1998 (1998-2015, *I am, I'll be*) was to identify factors that, coming into play during early childhood, affect the social adjustment and academic performance of young Quebecers.
The revised main objective (2017-2023) is to gain a better understanding of the factors that, when implemented at different stages in life, are linked to the overall well-being of young adults in Québec.
The main objective of QLSCD 2nd edition - Cohort 2018 and Cohort 2020-2021 (*Growing Up in Québec*) is to identify the developmental trajectories and factors that contribute to the well-being of young people born in Quebec. Some of its sub-objectives are:
* To study the factors that predict the adoption of healthy lifestyles and optimal health;
* To identify the predictors of school perseverance and success;
* To identify the process that promote social adaptation;
* To identify factors associated with social mobility; and
* To study the process that leads to successful socio-professional integration.
Overview
- Acronym
- QLSCD
- Website
- QLSCD
- Investigators
-
Dr. Élise LedouxInstitut de recherche Robert-Sauvé en santé et en sécurité du travail, Université du Québec à Montréal
- Contacts
-
General Design
- Study design
- Cohort
- Start - End Year
- 1996 -
- General Information on Follow Up (profile, frequency)
-
QLSCD 1 - Cohort 1996 was followed-up yearly from 5 months to 18 years old.
QLSCD 1 - Cohort 1998 was followed-up yearly from 5 months to about 25 years of age (in 2023), with breaks at ages 9, 11, 14, 16, 18, 20, 22, and 24.
QLSCD 2 - Cohort 2018 was followed-up every year since 2018.
QLSCD 2 - Cohort 2020-2021 was first contacted in March 2021 and is meant to be followed up to adulthood, every year or every two years.
- Recruitment Target
-
- Individuals
- Number of Participants
- 7,641
- Number of Participants with Biological Samples
- 1,572
- Supplementary information about number of participants
-
QLSCD 1 - Cohort 1996: 572 participants
QLSCD 1 - Cohort 1998: 2,120 participants
QLSCD 2 - Cohort 2018: 449 participants
QLSCD 2 - Cohort 2020-2021: 4,500 participants - Supplementary Information
-
QLSCD 1 - Cohort 1998: Other biological samples were collected when the participants were 17 years old.
QLSCD 2 - Cohort 2020-2021 did not collect biological samples.
Access
Availability of data and biosamples
| Possible Access to Data | |
| Possible Access to Biosamples | |
| Other |
|
- By contacting the study representative: Nancy Illick (Institut de la statistiques du Québec)
Sector of research
| Possible Access to Data | Possible Access to Biosamples | |
| Investigators from the public sector | ||
| Investigators from the private sector | ||
| Investigators from not-for-profit organization |
Transfer
| Possible Access to Data | Possible Access to Biosamples | |
| Can leave the study facility | ||
| Can leave the country |
Cost
| Possible Access to Data | No Cost |
| Possible Access to Biosamples | Variable Cost |
Cost reduction for co-analyses
| Possible Access to Data | |
| Possible Access to Biosamples |
Marker Papers
Orri M, Boivin M, Chen C et al. Cohort Profile: Quebec Longitudinal Study of Child Development (QLSCD). Social Psychiatry and Psychiatric Epidemiology, 2021;56: 883–894.
PUBMED 33185737Supplementary Information
QLSCD 1 - Cohort 1998: Questionnaires available here
QLSCD 2 - Cohort 2020-2021: Questionnaires soon to be available (in 2022) QLSCD 2 website
QLSCD 2 - Cohort 2020-2021: Questionnaires soon to be available (in 2022) QLSCD 2 website
Timeline
Populations
QLSCD 1 - Cohort 1998
The population was composed of babies (single births only) aged 59 or 60 gestational weeks at the beginning of each data collection period, born to mothers living in Quebec.
Selection Criteria
- Newborns
- Countries
-
- Canada
- Canadian Provinces
-
- Quebec
- Territory
- Quebec
- Health Status
-
Some children were excluded because of constraints linked to the sample frame or major health problems, such as premature babies whose gestation lasted less than 24 weeks or more than 42 weeks and babies whose sex was unknown at participant selection.
- Other Criteria
-
Mothers living in the sociosanitary areas 10 (North-of-Quebec), 17 (Cree territory) and 18 (Inuit territory) and mothers living on Indian reserves were excluded.
Minimum age: 59 gestational weeks at the beginning of each collection period at time 1
Maximum age: 60 gestational weeks at the beginning of each collection period at time 1
Sources of Recruitment
- General Population
-
- Selected sample
Sample Size
- Number of Participants
- 2,120
- Number of Participants with Biological Samples
- 1,000
- Supplementary information about number of participants
-
Data collection 1998: 2,120 participants
Data collection 1999: 2,045 participants
Data collection 2000: 1,997 participants
Data collection 2001: 1,950 participants
Data collection 2002: 1,944 participants
Nutrition Data collection 2002: 1,550 participants
Data collection 2003: 1,776 participants
Data collection 2004: 1,529 participants
Psychomotricity Data collection 2004: 1,529 participants
Data collection 2005: 1,537 participants
Data collection 2006: 1,526 participants
Psychomotricity Data collection 2006: 1,526 participants
Data collection 2008: 1,402 participants
Health Data collection 2008-2009: 1,000 participants
Data collection 2010: 1,415 participants
Data collection 2011: 1,312 participants
Data collection 2013: 1,466 participants
Data collection 2015: 1,348 participants
Data collection 2017: 1,401 participants
Mental Health Data collection 2018: 1,245 participants
Data collection 2019: 1,323 participants
Nutrition data collection 2020: 908 participants
COVID-19 data collection 2020: 1,182 participants
Data collection 2021: 1,337 participants
Resilience data collection 2021: 1,327 participants
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 1 | QLSCD 1 - Cohort 1998 - Data collection 1998 |
|
1998 (March) | 1998 (December) | |
| 2 | QLSCD 1 - Cohort 1998 - Data collection 1999 |
|
1999 (March) | 1999 (December) | |
| 3 | QLSCD 1 - Cohort 1998 - Data collection 2000 |
|
2000 (March) | 2000 (November) | |
| 4 | QLSCD 1 - Cohort 1998 - Data collection 2001 |
|
2001 (March) | 2001 (November) | |
| 5 | QLSCD 1 - Cohort 1998 - Data collection 2002 |
|
2002 (March) | 2002 (June) | |
| 6 | QLSCD 1 - Cohort 1998 - Nutrition Data collection 2002 |
|
2002 (March) | 2002 (July) | |
| 7 | QLSCD 1 - Cohort 1998 - Data collection 2003 |
|
2003 (March) | 2003 (June) | |
| 8 | QLSCD 1 - Cohort 1998 - Data collection 2004 |
|
2004 (March) | 2004 (June) | |
| 9 | QLSCD 1 - Cohort 1998 - Psychomotricity Data collection 2004 |
|
2004 (March) | 2004 (August) | |
| 10 | QLSCD 1 - Cohort 1998 - Data collection 2005 |
|
2005 (March) | 2005 (June) | |
| 11 | QLSCD 1 - Cohort 1998 - Psychomotricity Data collection 2006 |
|
2006 (March) | 2006 (June) | |
| 12 | QLSCD 1 - Cohort 1998 - Data collection 2006 |
|
2006 (March) | 2006 (June) | |
| 13 | QLSCD 1 - Cohort 1998 - Data collection 2008 |
|
2008 (February) | 2008 (June) | |
| 14 | QLSCD 1 - Cohort 1998 - Health Data collection 2008-2009 |
|
|
2008 (March) | 2009 (March) |
| 15 | QLSCD 1 - Cohort 1998 - Data collection 2010 |
|
2010 (February) | 2010 (June) | |
| 16 | QLSCD 1 - Cohort 1998 - Data collection 2011 |
|
2011 (February) | 2011 (June) | |
| 17 | QLSCD 1 - Cohort 1998 - Data collection 2013 |
|
2013 (February) | 2013 (June) | |
| 18 | QLSCD 1 - Cohort 1998 - Data collection 2015 |
|
|
2015 (February) | 2015 (June) |
| 19 | QLSCD 1 - Cohort 1998 - Biological Embedding of Childhood Adversity Data collection 2015 |
|
|
2015 (February) | 2015 (May) |
| 20 | QLSCD 1 - Cohort 1998 - Data collection 2017 |
|
2017 (February) | 2017 (May) | |
| 21 | QLSCD 1 - Cohort 1998 - Mental health Data collection 2018 |
|
2018 (March) | 2018 (June) | |
| 22 | QLSCD 1 - Cohort 1998 - Data collection 2019 |
|
2019 (February) | 2019 (June) |
QLSCD 1 - Cohort 1996
The population was composed of babies aged between 60 and 61 weeks of gestation at the beginning of the data collection who were born to mothers living in Quebec.
Selection Criteria
- Newborns
- Countries
-
- Canada
- Canadian Provinces
-
- Quebec
- Territory
- Quebec, Montreal, Chaudière-Appalaches, Laval, Lanaudière, Laurentides and Montérégie
- Other Criteria
- English or French-speaking
Sources of Recruitment
- General Population
-
- Selected sample
- Supplementary Information
-
Participants were selected from specific health regions; the towns located about less than an hour drive from Montreal. Health regions located approximately less than an hour drive from Quebec City were also selected. The cities were chosen based on two criteria: the population of the city and the available traffic routes. After the sample was drawn by the Bureau de la statistique du Québec, Santé Québec received the list of names, addresses and telephone numbers of households to be interviewed. Recruitment was done through telephone calls.
Sample Size
- Number of Participants
- 572
- Number of Participants with Biological Samples
- 572
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | QLSCD 1 - Cohort 1996 - Data collection 1996 |
|
1996 (October) | 1997 (September) | |
| 1 | QLSCD 1 - Cohort 1996 - Data collection 1997 |
|
1997 (October) | 1998 (September) | |
| 2 | QLSCD 1 - Cohort 1996 - Data collection 1998 |
|
1998 (November) | 1999 (October) | |
| 3 | QLSCD 1 - Cohort 1996 - Data collection 1999 |
|
1999 (November) | 2000 (October) | |
| 4 | QLSCD 1 - Cohort 1996 - Data collection 2001 |
|
2001 (May) | 2002 (April) | |
| 5 | QLSCD 1 - Cohort 1996 - Data collection 2002 |
|
2002 (May) | 2003 (April) | |
| 6 | QLSCD 1 - Cohort 1996 - Data collection 2003 |
|
2003 (May) | 2004 (April) | |
| 7 | QLSCD 1 - Cohort 1996 - Data collection 2004 |
|
2004 (May) | 2005 (April) | |
| 8 | QLSCD 1 - Cohort 1996 - Data collection 2005 |
|
2005 (May) | 2006 (April) | |
| 9 | QLSCD 1 - Cohort 1996 - Data collection 2006 |
|
2006 (May) | 2007 (April) | |
| 10 | QLSCD 1 - Cohort 1996 - Data collection 2007 |
|
2007 (May) | 2008 (April) | |
| 11 | QLSCD 1 - Cohort 1996 - Data collection 2008 |
|
2008 (May) | 2009 (April) | |
| 12 | QLSCD 1 - Cohort 1996 - Data collection 2009 |
|
2009 (May) | 2010 (April) | |
| 13 | QLSCD 1 - Cohort 1996 - Data collection 2010 |
|
2010 (May) | 2011 (April) | |
| 14 | QLSCD 1 - Cohort 1996 - Data collection 2011 |
|
2011 (May) | 2012 (April) | |
| 15 | QLSCD 1 - Cohort 1996 - Data collection 2012 |
|
2012 (May) | 2013 (April) | |
| 16 | QLSCD 1 - Cohort 1996 - Data collection 2013 |
|
2013 (May) | 2014 (April) | |
| 17 | QLSCD 1 - Cohort 1996 - Data collection 2014 |
|
2014 (May) | 2015 (April) |
QLSCD 2 - Cohort 2018
The population is composed of babies aged 59 or 62 gestational weeks at the beginning of the data collection period, born between January 23rd and September 5, 2018 to mothers living in 3 selected sociosanitary regions: Montréal, Mauricie–Centre-du-Québec and Montérégie.
Selection Criteria
- Newborns
- Countries
-
- Canada
- Canadian Provinces
-
- Quebec
- Territory
- Montréal, Mauricie–Centre-du-Québec and Montérégie
- Other Criteria
-
Inclusion: Minimum age: 59 gestational weeks at the beginning of each collection period at time 1
Maximum age: 60 gestational weeks at the beginning of each collection period at time 1
Exclusion: death at birth, family lives outside Quebec permanently or in a region excluded from the study
Sources of Recruitment
- General Population
-
- Selected sample
- Supplementary Information
-
Participants were selected from the "Fichier de Naissances Vivantes" in the targeted sociosanitary regions and from the "Paiement de l’allocation aux familles de Retraite Québec". They are thereafter invited to participate.
Sample Size
- Number of Participants
- 449
- Number of Participants with Biological Samples
- 449
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | QLSCD 2 - Cohort 2018 - Data collection 2018 |
|
2018 (October) | 2019 (March) | |
| 1 | QLSCD 2 - Cohort 2018 - Data collection 2019 |
|
2019 (October) | 2020 (March) | |
| 2 | QLSCD 2 - Cohort 2018 - Data collection 2020 |
|
2020 (October) | 2020 (December) | |
| 3 | QLSCD 2 - Cohort 2018 - Data collection 2021 |
|
2021 (October) | 2022 (March) |
QLSCD 2 - Cohort 2020-2021
The population is composed of babies aged 60 gestational weeks at the beginning of each data collection period, born between October 1st, 2020 and September 30th, 2021 to mothers living in Quebec, in rural and urban settings and from low socio-economic status.
Selection Criteria
- Newborns
- Countries
-
- Canada
- Canadian Provinces
-
- Quebec
- Territory
- Bas-Saint-Laurent, Saguenay–Lac-Saint-Jean, Capitale-Nationale, Mauricie-et-Centre-du-Québec, Estrie, Montréal, Outaouais, Abitibi-Témiscamingue, Côte-Nord, Gaspésie–Îles-de-la-Madeleine, Chaudière-Appalaches, Laval, Lanaudière, Laurentides, Montérégie
- Other Criteria
-
Inclusion: 60 gestational weeks at the beginning of each collection period at time 1
Exclusion: Babies whose gestation lasted less than 24 weeks or more than 42 weeks; whose family is living in the the sociosanitary areas of Northern Quebec, Nunavik or the Cree Territory of James Bay and whose mothers are living on Indian reserves
Sources of Recruitment
- General Population
-
- Selected sample
- Supplementary Information
-
Participants were selected from the "Fichier de Naissances Vivantes" in the targeted sociosanitary regions and were thereafter invited to participate.
Sample Size
- Number of Participants
- 8,200
- Number of Participants with Biological Samples
- 8,200
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | QLSCD 2 - Cohort 2020-2021 - Data collection 2021 |
|
2021 (May) | 2022 (March) | |
| 1 | QLSCD 2 - Cohort 2020-2021 - Data collection 2022 |
|
2022 (May) | 2023 (March) |
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
No Areas of Information Collected
No Scales Collected
Areas of Information Collected per per Population and Data Collection Event
No Areas of Information Collected
No Scales Collected
Networks
| Acronym | Name | Harmonization Initiatives | Individual Studies |
|---|
Last Update: 2023-04-18T13:45:43.240