Evaluating the validity of a two-stage sample in a birth cohort established from administrative databases

El-Zein, Mariam; Conus, Florence; Benedetti, Andréa; Parent, Marie-Élise; Rousseau, Marie-Claude (2015). Evaluating the validity of a two-stage sample in a birth cohort established from administrative databases Epidemiology , vol. 27 , nº 1. p. 105-15. DOI: 10.1097/EDE.0000000000000403.

Prévisualisation

PDF - Version soumise Disponible sous licence Creative Commons Attribution. Télécharger (261kB) | Prévisualisation

Résumé

BACKGROUND: When using administrative databases for epidemiologic research, a subsample of subjects can be interviewed, eliciting information on undocumented confounders. This article presents a thorough investigation of the validity of a two-stage sample encompassing an assessment of nonparticipation and quantification of the extent of bias.

METHODS: Established through record linkage of administrative databases, the Quebec Birth Cohort on Immunity and Health (n=81,496)aims to study the association between Bacillus Calmette-Guerin (BCG) vaccination and asthma. Among 76,623 subjects classified in 4 BCG-asthma strata, a two-stage sampling strategy with a balanced design was used to randomly select individuals for interviews. We compared stratum-specific socio demographic characteristics and healthcare utilization of Stage 2 participants (n=1643) with those of eligible nonparticipants (n=74,980) and non respondents (n=3157). We used logistic regression to determine whether participation varied across strata according to these characteristics. The effect of nonparticipation was described by the relative odds ratio (ROR=ORparticipants/ORsource population) for the association between socio demographic characteristics and asthma.

RESULTS: Parental age at childbirth, area of residence, family income, and healthcare utilization were comparable between groups. Participants were slightly more likely to be women and have a mother born in Quebec. Participation did not vary across strata by sex, parental birthplace, or material and social deprivation. Estimates were not biased by nonparticipation; most RORs were below one and bias never exceeded 20%.

CONCLUSIONS: Our analyses evaluate and provide a detailed demonstration ofthe validity of a two-stage sample for researchers assembling similar research infrastructures.

Type de document:	Article
Mots-clés libres:	Bacillus Calmette-Guérin; asthma; birth cohort; administrative data; probabilistic linkage; two-stage sampling; response rate; internal validity
Centre:	Centre INRS-Institut Armand Frappier
Date de dépôt:	29 août 2016 21:00
Dernière modification:	01 févr. 2017 10:10
URI:	http://espace.inrs.ca/id/eprint/3183

Actions (Identification requise)

Modifier la notice