The phrase "a previous study investigated" is correct and usable in written English.
It can be used when referring to research or findings from an earlier study in academic or scientific writing.
Example: "A previous study investigated the effects of sleep on cognitive performance, providing valuable insights into the relationship between rest and mental function."
Alternatives: "an earlier study examined" or "a prior study analyzed".
A previous study investigated lipid accumulation using a medium containing 3%% glucose by Vanrija musci JCM 24512 (formally Cryptococcus musci) (Tanimura et al. 2014b).
A previous study investigated the effects of the preload and taper-angle mismatch in tapered implant systems on the removal force characteristics of the self-locking mechanism.
A previous study investigated the influence of thumb sucking and pacifier use on breastfeeding patterns in exclusively breastfed infants, on the duration of exclusive breastfeeding, and on the total breastfeeding duration.
A previous study investigated the attitudes of physicians toward NHAP treatment guidelines and found that the core obstacles to implementation of the ATS/IDSA guidelines are apprehensions regarding the practicality of using the suggested regimens and absence of documented improved outcomes [13].
A previous study investigated the activities of compounds demonstrated to be active in zebrafish embryo bioassays, in both zebrafish and mammalian cell lines [56].
A previous study investigated mutations in Gli3 exons 9, 10, 11 and 12 [ 26].
A previous study investigating the sibility of discrimination in patterns of sentencing was carried out by Roger Hood in the West Midlands in 1992.
This observation is consistent with a previous study investigating active range of motion.
These findings suggest an association between migraine and alexithymia and are consistent with those obtained in a previous study investigating the relationship between alexithymia and TTH [16].
The questionnaires were adapted from a previous study investigating perceptual experiences during the traditional rubber hand illusion [22].
A previous study investigating the relationship between unstable angina and the BDNF Val66Met polymorphism similarly identified a protective effect of the Met/Met genotype [16].
