Some misclassification could arise because leptin was measured only once, although single measurements of circulating leptin appear to reflect long-term levels rather well [ 67, 68].
Firstly, the authors state that their study is limited due to the lack of more frequent blood flow measurements, as all parameters were measured only once thirty minutes after switching to a new mean airway pressure (Pmean).
The investigation of children required adaptation of previously established protocols, i.e. the maximum temperature for localized warming was set to 40°C instead of 42°C and blood pressure was measured only once before starting the LDF measurements.
First, creatinine concentration and CAC were measured only once, and thus the reliability of these measurements could not be evaluated.
UAER was measured only once while current recommendations suggest two consecutive measurements to diagnose micro-/macro-albuminuria [ 25].
That, combined with the difficulty of gaining safe access and the sheer number of places that have to be monitored, means the thickness of the walls of some pipes might be measured only once every four years or so.
(a) Sample PL was measured at two perpendicular directions named PL1 and PL2 and (b) sample PP measured only once.
Since IAP was measured only once, a diagnosis of IAH or ACS could by definition not be made.
Leaf reflectance and transmittance were measured only once, which was not sufficient to represent optical features for the entire growing season.
One sample broke; consequently, thermal conductivity was measured only once for three of the five rock samples, and only twice for the other two samples (Table 1).
14The reverse causality (search causing unhappiness) is avoided here because we are using the initial drop in happiness, which predates the search, is measured only once, and is time-invariant.
