Maelstrom Research

Quebec Longitudinal Study of Kindergarten Children

The study examined the prevalence of behaviour problems during the elementary school years using a developmental perspective. Four major aims were defined: - to describe the different developmental trajectories among children from their entry into kindergarten to their entry into the work force; - to identify the factors that enable us to recognize, from kindergarten, those children who are at risk of developing adjustment problems over the course of their schooling education; - to identify the protective factors that will enable children to succeed in school and to adapt well socially, in spite of unfavorable elements in their environment; - to contribute to the knowledge necessary for the development of programs adapted to high risk children.

Overview

Acronym

QLSKC

Investigators

Dr. Richard E. Tremblay

Université de Montréal

Dr. Frank Vitaro

Université de Montréal

Contacts

Katja Valois

Université de Montréal

General Design

Study design

Cohort

Start - End Year

1986 -

General Information on Follow Up (profile, frequency)

To date, 12 data collections have been conducted over 24 years (1986–2010), and three generations of participants have been involved in the study (i.e. the study child, his parents and the study child’s first child). Data on the participants were obtained via teacher reports yearly from age 6–12 years; via parent reports from age 6–19 years; and via the participants themselves at age 13–29 years. Finally, data on the study child’s first child were obtained via paper or web-based questionnaires rated by the participant (now a parent).

Recruitment Target

Individuals

Number of Participants

3,017

Number of Participants with Biological Samples

3,017

Access

General Information

Availability of data and biosamples

Possible Access to Data
Possible Access to Biosamples
Other

Yes

Not applicable

Don't know

Marker Papers

Rouquette A, Cote SM, Pryor LE, et al. Cohort Profile: The Quebec Longitudinal Study of Kindergarten Children (QLSKC). International Journal of Epidemiology, 2012; 43(1), 23-33.

PUBMED 23159828

Timeline

Population

Data on the participants were obtained via teacher and parent reports yearly from age 6 to 8 years. Self-administered questionnaires, such as The Social Behaviour Questionnaire were completed by both teacher and parent to assess the behaviour of the child. The emotional climate for the child and his/her temperament were assessed by the parent. Information concerning the child (perinatal information, sleep, life events during the previous year, school environment, puberty, etc.) or his/her family (socio-demographic information, general health, etc.) was also collected during this period.

Start Date

1986

End Date

1988

Data sources

Questionnaires

Start Date

1987

End Date

1989

Data sources

Questionnaires

Start Date

1988

End Date

1990

Data sources

Questionnaires

Start Date

1989

End Date

1991

Data sources

Questionnaires

Self-administered questionnaires, such as The Social Behaviour Questionnaire were completed by both teacher and parent to assess the behaviour of the child. The emotional climate for the child and his/her temperament were assessed by the parent. Information concerning the child (perinatal information, sleep, life events during the previous year, school environment, puberty, etc.) or his/her family (socio-demographic information, general health, etc.) was also collected during this period. The child completed the Pubertal Development Scale.

Start Date

1990

End Date

1992

Data sources

Questionnaires

Start Date

1991

End Date

1993

Data sources

Questionnaires

Start Date

1992

End Date

1994

Data sources

Questionnaires

At age 13 years (grade 7), adolescents who attended a school where there were at least six other study participants were invited to self-report their delinquent behaviours via paper and pencil questionnaires. The Self-Rating Questionnaire collected socio-demographic data as well as information on family life, relationships, activities and jobs, sexuality, and school environment and progress. Furthermore, the Social Behaviour Questionnaire, Pubertal Development Scale, Child Depression Inventory and Self-Description Questionnaire were also completed.

Start Date

1993

End Date

1995

Data sources

Questionnaires

The Self-Rating Questionnaire collected information about socio-demographics, school environment and progress, activities and jobs, general health, alcohol and drug use, delinquency and legal issues, professional services use, as well as life events and relationships.At age 15 years, children and their parents were invited separately to undergo a structured psychiatric interview using the Diagnostic Interview Schedule for Children (DISC) and to fill out questionnaires concerning their life habits and the family history of mental health problems.

Start Date

1995

End Date

1997

Data sources

Questionnaires

When the participants were 19 years old, information on the familial determinants of the young adults’ psychosocial adjustment (activities, feelings, relationships and behaviours) was collected.

Information about high school graduation was accessed from the Quebec Ministry of Education.

Start Date

1999

End Date

2002

Data sources

Questionnaires

The Self-Rating Questionnaire collected information about socio-demographics, school environment and progress, activities and jobs, general health, alcohol and drug use, delinquency and legal issues, professional services use, as well as life events and relationships. Participants underwent diagnostic interviews about mental health and personality. The Suicidal Intent Scale and Scale for Suicidal Ideation were completed.

Blood and saliva samples were collected.

Information about high school graduation was accessed from the Quebec Ministry of Education.

Information on delinquency was obtained from judicial records.

Start Date

2001

End Date

2004

Data sources

Questionnaires
Biosamples
Administrative databases

Data sources - Biosamples

Blood
Saliva

Data sources - Administrative databases

Socioeconomic databases

At age 29 years, data concerning gambling practices and the main dimensions previously assessed were collected on a subsample of subjects who had complete data from the 15 or 22 years waves. This last wave was the first opportunity to collect information on the first child of the 573 participants who were parents at that time. Six versions of the questionnaire were developed according to children’s age group to assess various dimensions including pregnancy, health, sleep, behaviour, peer-relationships, childcare, school progress, parental attitudes and child environment.

In addition, saliva samples were collected from 392 children for genetic analysis.

Reports from the Director of Youth Protection (DYP) and information about post-secondary study degrees were collected as well.

Start Date

2008

End Date

2010

Data sources

Questionnaires
Biosamples

Data sources - Biosamples

Saliva

QLSKC population

The population consisted of kindergarten boys and girls attending French-speaking public schools in the Canadian province of Quebec during the 1986-87 and 1987-88 school years. Two thousand children representative of the population and 1017 children exhibiting disruptive behaviour problems were included in the cohort.

Selection Criteria

Minimum age

Countries

Canada

Canadian Provinces

Quebec

Other Criteria

Attending French-speaking public schools

Sources of Recruitment

General Population

Selected sample

Supplementary Information

2000 (1001 boys) of the subjects were chosen randomly and proportionally according to the 11 administrative regions of Québec, to create a representative sample of the children who attended kindergarten in a francophone public school in the province of Quebec in the 1986-87 and 1987-88 school years. The remaining 1017 children (593 boys) scored at or above the 80th percentile for disruptive behaviors at the end of kindergarten (age 6 years) with gender-specific cut-offs.

Sample Size

Number of Participants: 3,017
Number of Participants with Biological Samples: 3,017

Data Collection Events

#	Name	Data sources	Data sources - Biosamples	Start	End
0	QLSKC - Kindergarten	Questionnaires		1986	1988
1	QLSKC - Grade 1	Questionnaires		1987	1989
2	QLSKC - Grade 2	Questionnaires		1988	1990
3	QLSKC - Grade 3	Questionnaires		1989	1991
4	QLSKC - Grade 4	Questionnaires		1990	1992
5	QLSKC - Grade 5	Questionnaires		1991	1993
6	QLSKC - Grade 6	Questionnaires		1992	1994
7	QLSKC - Grade 7	Questionnaires		1993	1995
8	QLSKC - 15 to 17 years	Questionnaires		1995	1997
9	QLSKC - 19 to 21 years	Questionnaires		1999	2002
10	QLSKC - 22 to 24 years	Questionnaires Biosamples Administrative databases	Blood Saliva	2001	2004
11	QLSKC - 29 to 31 years	Questionnaires Biosamples	Saliva	2008	2010

Participating Studies

Acronym	Name	Study design	Countries

Harmonization Initiatives Included

Acronym	Name

Datasets

Search Variables

Name	Data Collection Events	Variables

Variables Content Summary

Areas of Information Collected per per Population and Data Collection Event

Networks

Acronym	Name	Harmonization Initiatives	Individual Studies

Last Update: 2024-02-27T16:02:47.721

Quebec Longitudinal Study of Kindergarten Children

Overview

General Design

Access

Marker Papers

Documents

Timeline

Population

Selection Criteria

Sources of Recruitment

Sample Size

Documents

Data Collection Events

Participating Studies

Harmonization Initiatives Included

Datasets

Areas of Information Collected

Variables Content Summary

Areas of Information Collected

Areas of Information Collected per per Population and Data Collection Event

Networks

Quebec Longitudinal Study of Kindergarten Children

Overview

Richard E. Tremblay

Frank Vitaro

Katja Valois

General Design

Access

Marker Papers

Documents

Timeline

Population

QLSKC - Kindergarten

QLSKC - Grade 1

QLSKC - Grade 2

QLSKC - Grade 3

QLSKC - Grade 4

QLSKC - Grade 5

QLSKC - Grade 6

QLSKC - Grade 7

QLSKC - 15 to 17 years

QLSKC - 19 to 21 years

QLSKC - 22 to 24 years

QLSKC - 29 to 31 years

Selection Criteria

Sources of Recruitment

Sample Size

Documents

Data Collection Events

Participating Studies

Harmonization Initiatives Included

Datasets

Areas of Information Collected

Variables Content Summary

Areas of Information Collected

Areas of Information Collected per per Population and Data Collection Event

Networks