We recognize the benefits of longitudinal studies and their value for confirming cause-and-effect relationships.
Prospective studies are necessary to confirm cause and effect in this association.
By manipulating blood sugar levels in mice and monkeys, researchers said, they tried to confirm a cause-and-effect relationship between the glucose spikes and the reduced blood volume, Dr. Small said.
Of course, this observation does not confirm a cause-and-effect relationship.
However, as its follow-up period was limited to only 1 year, that relationship might have been susceptible to reverse causality; longer follow-up is therefore necessary to confirm the cause-and-effect relationship between dysregulated sMg levels and future cardiovascular disease.
However, there is no scientific research confirming a direct cause-and-effect relationship between skipping breakfast and gaining weight.
Prospective studies are necessary to confirm the cause and effect in this association.
Even though, the study covered all nurses working in all referral hospitals found in Amhara regional state it has the following limitations: First, the cross-sectional nature of the study design does not confirm definitive cause and effect relationship.
Although it is possible that immune suppression as represented by the reduced levels of expression of CMI-associated cytokine genes TNF and IFNG could be the reason behind progression of the disease to stage 4, this study is able to establish the correlation but unable to confirm the cause and effect relationship.
Nevertheless, population-based prospective cohort studies are needed to confirm the apparent cause-and-effect relationship between UI and breathlessness.
A cause-and-effect relationship was confirmed in two large prospective randomized clinical trials that have shown an improved morbidity and mortality with tight glycemic control with insulin infusion in fed critically ill patients [ 67, 68].
