Follow-up questionnaires are mailed biennially to the entire cohort to update information on potential risk factors and ascertain new cases of disease.
As larger numbers of animals are sequenced, the assay can be adjusted to exclude those markers that are uninformative and ascertain new markers where needed.
The participants were followed up with home visits every 2 3 years to update exposure information and to ascertain new diagnosis of cancers.
Biennial follow-up questionnaires were sent to the women to update information regarding diet and other lifestyle-related factors and to ascertain new diagnoses of major illnesses, including breast cancer.
The methods to ascertain new cases of type 2 diabetes varied among studies: in five studies, questionnaires were used (8, 9, 11, 15, 17), with additional validation (8, 9); in the other five studies, more direct diagnostic criteria were used (10, 12– 16, 16).
Since the goal of the parent trial was to measure the effect of micronutrient supplementation on pregnancy-related mortality, all women who were eligible to become pregnant and who gave consent for surveillance were visited every five weeks to ascertain new pregnancies.
In contrast, they can also be ascertained from new mutation families and these new mutation alleles are more prone to repeat expansion when compared with similar-sized alleles in the general population.
Since the extension of the new born screening in the Netherlands we, and others, have experienced that low carnitine ascertained during new born screening can be associated with low maternal plasma carnitine levels [12].
Recently, we and others ascertained a new localisation site and regulatory mechanism for the protein (Tourneur et al, 2008), Kriebardis et al, 2008).
