The phrase "a study has tested" is correct and usable in written English.
It can be used when discussing research findings or methodologies in academic or scientific contexts.
Example: "A study has tested the effects of sleep deprivation on cognitive performance."
Alternatives: "research has examined" or "an investigation has assessed".
In support of the involvement of serotonergic mechanisms in MSG induced toxicity, a study has tested the MSG induced lethality (MSG; 6 10 g/kg, intra-peritoneal) in mice after adding drugs that depletes serotonin stores, this resulted in an increase in MSG-induced lethality (Kamei et al., 1991).
For example, a study has tested the validity and responsiveness of the ankle functional score (AFS) based on fundamental functional outcomes such as pain, swelling, weight bearing, stability, and gait, and concluded that the AFS is easy to use and might be employed alongside subjective clinical assessment to evaluate recovery after acute ankle sprain [ 48].
A new study has tested supermarket chicken and found that one in four had antibiotic-resistant E. coli present in it.
A recent study has tested the effect of Mindlight on anxiety symptoms in school children [ 20].
A more recent study has tested the hypothesis that climate has shaped variation in metabolism genes by genotyping more than 800 SNPs at 82 candidate genes for common metabolic disorders in 54 worldwide populations (Hancock et al. 2008).
23 This study has tested a twice-daily administration which determined an effective improvement of disease.
This study has tested a limited number of ETEC strains and the origin of these isolates is also limited to two mayor urban centers in northern Colombia.
The SPQ factor structure at item level has been rarely replicated and no study had tested a bifactor model of the SPQ so far.
A series of studies has tested for phenotypic differences between Turner females with the intact X inherited either maternally or paternally (Hamelin et al. 2006; Bondy et al. 2007; Sagi et al. 2007).
A set of research studies has tested the respective influence of each dimension (Schmelter et al. 2010).
The novelty of this study is in the proposed application at relatively high temperatures (450°C and 500°C); only a few studies have tested carbon membrane reactors.
