However, as discussed in detail by Brunello, Weber and Weiss (2012), existing validation studies find that recall bias is not so severe, arguably because of the state-of-the-art elicitation methods used: respondents are helped to locate events along the time line, starting from domains that are more easily remembered, and then asked progressively more details about them.
Although traditional filial piety emphasizes all-round support from adult children to their parents, existing studies have found that material support was the main and sometimes only old age support actually provided (Miller 2004).
Existing studies also found that socio-demographic characteristics confounded the association between proxy response and health and functional limitations [ 3, 8, 9].
Several epidemiologists presented as-yet unpublished work, which built on existing studies, that found no connection between abortion and cancer.
A recent review of existing quality assessment tools for diagnostic accuracy studies found that 12 of 67 tools (18%) incorporated a quality score[ 17].
Two studies found that pre-existing and gestational hypertension in the US were associated with more than 60% greater odds of spontaneous PTB, but PPROM was not evaluated [ 29, 32].
In accordance with the results of existing studies, this study found that the personal traits of family members, the living conditions of residents in the LTC facilities, and family members' experiences with LTC facilities were associated with the decision-making factors for placing relatives in LTC facilities [ 1, 3, 14, 17- 21].
Now a systematic review of existing studies has found no evidence that the restrictions have any benefit for most healthy women and their babies.
When combining studies of smokers with and without pre-existing disease, the study found that doctors could expect to get one extra cardiac event associated with Chantix for every 28 smokers they treated with the drug.
The burden of data collection is considered by many to be a deterrent to routine use [ 10], however, and one study found that existing scoring systems were inadequate for this purpose [ 9].
