The phrase "a relatively long interval" is correct and usable in written English.
You can use it when discussing time periods that are longer than average but not excessively long, often in contexts like research, studies, or observations.
Example: "The experiment was conducted over a relatively long interval, allowing for more accurate data collection."
Alternatives: "a fairly extended period" or "a somewhat lengthy duration".
While the GSS is a repeated cross-section which covers a relatively long interval of time, the HILDA survey is a longitudinal dataset with a limited time dimension.
However, imaging with radiolabeled whole antibodies requires a relatively long interval between injection and imaging acquisition for adequate contrast to develop due to the slow accretion of intact antibodies in tumors and their slow clearance [7].
Walcott and colleagues [ 63] found a relatively long interval between arrival and intervention in patients transferred for neurosurgical evaluation.
Thus, there is justified concern that CYD vaccinated individuals could develop severe disease if infection with DENV-2 occurs after a relatively long interval of time.
This may be useful in JIA, as weight-based dosing and a relatively long interval between infusions have advantages in children.
First, the time required for accumulation of all genetic alterations in a parental clone suggests a relatively long interval for potentially curative screening methods in this disease, in the order of a decade or longer [ 53].
Additional vaccine-related issues included the need for clean water for Dukoral administration and the relatively long interval after vaccination before immunity develops.
The relatively long interval between onset of symptoms and hospitalization and the frequent lack of lower urinary tract symptoms suggest alternative and adjunctive explanations.
A more objective approach would have been to review all of the medical records concerning the obstetrical histories for the cases and controls, but this was not possible due to loss of patient files related to the relatively long interval between pregnancy and the development of SSc.
We think this would have had little effect in our study, because of the relatively long interval between the two moments of testing, and because in almost all cognitive domains, participants declined (Fig. 2), which would be the opposite when learning effects would have great impact.
Specifically, the identified time-point will separate the time intervals into a class of (relatively long) intervals that are between the bouts of behavior (interbout intervals) and a class of (relatively shorter) intervals that belong within a bout of behavior (intrabout intervals; Tolkamp et al., 1998; Tolkamp & Kyriazakis, 1999).
