Steve Tuttle, the Taser International spokesman, said Zipes's report is "based on uncontrolled and anecdotal observations", and noted in an email to the Guardian that it "does not prove a cause-effect association".
Lack of clear cause-effect association between Nrt2.1 expression and cellular NO3 − contents under various NO3 − availabilities reflects the complex regulation of nitrate homeostasis and nitrogen metabolism during plant growth and development.
Currently there is no epidemiologic research reported from Asia that has addressed the cause-effect association between sun exposure and cutaneous melanoma.
Therefore, all results from the present study cannot be interpreted as a cause-effect association, although this association has been supported by few longitudinal studies [ 38– 438.
As our meta-analysis was based on results from observational studies, however, the association could still be subject to residual confounding or reverse causation bias and therefore does not allow inference of a cause-effect association.
Although the sigma PCBs-P4 relationship in female polar bears with offspring is not evidence per se of a direct cause-effect association, the results indicate that PCBs may affect levels of P4 in polar bear females.
Herein, we used a cross sectional design to address the main question of association between noise exposure and high blood pressure and this type of study design does not allow us to guarantee that exposure precedes the outcome, a condition to confirm a cause-effect association.
Reported prognostic indicators may be complications of ADPKD that are exacerbated by disease progression, rather than factors driving the underlying progression of the disease, or may exhibit a cause-effect association, in which they both exacerbate and are worsened by the progression of the disease.
On the contrary, humans instinctively search for cause-effect associations fulfilling a need for "control" that is comforting in the relationships with the world around us.
Finally, we cannot conclude any cause-effect associations from this cross-sectional study.
Limitations of this study include the cross-sectional design, which prevents us from determining any cause-effect associations.
