Sentences with phrase «observational studies however»

Results from observational studies however, have been inconsistent and vary by cancer site and other factors, including gender and genetic risk.

Not exact matches

On the evidence side, I know that the evidence primarily comes from observational studies, and there are methodological issues with measuring dose and duration of breastfeeding particularly after the introduction of complementary foods, however the evidence is fairly consistent in showing a reduction in gastrointestinal, respiratory and ear infections (see «Breastfeeding and maternal and infant outcomes in developed countries» http://www.ncbi.nlm.nih.gov/pubmed/17764214).

However, the results of observational studies from developing countries are consistent with the findings of the two Honduran trials, particularly with respect to growth.

However, in contrast, the observational arm of this study (in which infants were not at high risk of developing atopic disease) did not demonstrate differences in the incidence of atopic dermatitis.

«A number of observational studies and randomized trials, however, showed that routine episiotomy is associated with an increased incident of anal sphincter and rectal tears,» write the authors of Williams Obstetrics (23rd edition, p. 401, their emphasis), including a four to sixfold risk of fecal or flatus incontinence.

However, the studies the agency reviewed were almost all observational — meaning the researchers looked at rates of a given health problem among infants whose mothers chose to breastfeed and those whose mothers did not.

However, as with other observational studies, these results may have been affected by confounding variables that were unknown and thus not accounted for, and the observation of an association gives no proof of causality.

However, the study used self - reported alcohol consumption and relied on observational data, so no firm conclusions can me made about cause and effect.

«The sources of this liquid water will require more observational studies; however, the research shows that the effects of relatively small amounts of water on Mars in forming features on the surface may have been widely underestimated.

Now, however, two astronomers from the Complutense University of Madrid have applied a new technique, less exposed to observational bias, to study a special type of trans - Neptunian objects: the extreme ones (ETNOs, located at average distances greater than 150 AU and that never cross Neptune's orbit).

The researchers point out, however, that it was an observational study and that no definite conclusions about causality between Apgar score and the risk of neurological morbidity in babies can be drawn.

The institute panel, however, discarded a raft of observational studies, in which researchers compare the health of populations who take vitamin D supplements with those who do not.

«Results from our observational study in young adults with normal kidney function may not translate into a clinically meaningful difference and may be insufficient to inform decision - making concerning marijuana use; however, it is possible that the association between marijuana use and kidney function could be different in other populations such as older adults or patients with kidney disease, so additional research is needed,» said Dr. Ishida.

However, our observational study found subtle effects in estrogen - responsive tissues in soy - fed infants, and we don't know if these differences are associated with long - term health effects.»

However, it is a tricky subject to study as with observational data we often can not separate the effects of drug treatment from other risk factors such as maternal illnesses.

However, the supporting evidence is limited and mainly based on observational studies and short - term clinical trials (1, 2).

Fourthly, as with all observational studies, residual confounding by other factors can not be totally excluded; however, the consistently observed null results in both men and women argued against missing strong associations.

However, this is an observational study in which the change in total fiber is small [mean (± SD) change = 0.57 ± 6.37 g / d].

However, the recommendation to eat fruit and vegetables to prevent chronic diseases is mainly based on observational epidemiological studies, which leaves much uncertainty regarding the causal mechanism of this association.

However, one large observational study linked decaf coffee with reduced liver enzyme levels, which suggests a protective effect (23).

However, many of these studies are observational, meaning the participants» diets weren't controlled, so there could be other factors affecting the risk of cancer.

However, these studies are only observational, which means they can't prove eating peanuts actually causes the reduction in these risks.

It is known, however, from an increasing number of long - term observational studies, that the unique physiologic conditions and complications of pregnancy predict future disease risk for both mothers and their offspring.

However, observational studies can not clarify whether the observed epidemiologic association is a causal effect or the result of some unmeasured confounding variable.

How the relationship works isn't clear, however, and the study was observational, meaning it can't prove a direct cause - and - effect relationship.

However, most observational studies have reported either no association or positive associations between protein intake and bone mineral density in children, adults, and elderly subjects (reviewed in 12).

It's noteworthy, however, that the observational estimates of pilot high school treatment effects are larger for schools used in the lottery study than for other pilot schools.

However, observational studies have found that parents and caregivers often fail to secure them tightly or make other installation mistakes.

However, Yin (2005) studied the poleward shift of storm tracks PROJECTED to occur in the 21st century and contains no observational data.

However, if the non-radiative impacts from land use changes create warming that offsets the albedo - induced cooling, then observational studies would be more accurate than Marvel's model, at least insofar as land use impacts are concerned.

Subsequent observational studies and simulations with coupled atmosphere — ocean models have found similar multidecadal climatic modes, typically originating in the North Atlantic Ocean; however, the excitation source or sources of these oscillations have not been unambiguously identified (Knight 2009).

However, this is not true when the effective radiative forcing (ERF) measure of aerosol forcing — preferred by IPCC AR5 and used in the observational studies Marvel et al. criticises — is employed.

Observational studies provide a more objective perspective on parenting behaviors than parent or child report (Kerig, 2001); however, few studies have directly observed collaborative and intrusive parenting behaviors to corroborate those conclusions.

However, as for any observational study, we are unable to exclude the possibility of residual confounding for example by other characteristics associated with parent ADHD.