The phrase "a study which was conducted" is correct and usable in written English.
It can be used when referring to a specific research study that has been carried out in the past.
Example: "The findings of a study which was conducted in 2020 revealed significant trends in consumer behavior."
Alternatives: "a study that was performed" or "a study that was carried out".
The results presented in this paper rely on a study which was conducted in the framework of the research program INKLIM-A founded by the federal state Hesse which brought together experts of several environmental sciences, including experts for climate modelling.
This finding is in line with a study which was conducted in East Gojam [ 12].
A study which was conducted by Bagley and coworkers (1998) compared SME and DF emissions concerning PM, PAH, nPAH, and toxicity.
For such a study, which was conducted in only one city, it is difficult to generalize about the climacteric among Turkish women.
A study, which was conducted using the database from the 1996 Medical Expenditure Panel Survey, has shown that PIM is a predictor for and is associated with poor patient HRQoL.
Moreover, a study which was conducted in the USA [ 36] showed that ranolazine as add-on to SoC is a cost-effective treatment in patients with weekly or daily angina with an ICER of $32,682 per QALY.
The model was investigated in a qualitative study, which was conducted in a blended academic course, including synchronous and asynchronous lessons.
First, this is a preliminary study which was conducted in a Japanese routine clinical setting.
The younger group (born after 1980) consisted of five students of medicine, which were detected by a screening study which was conducted by means of a questionnaire (see [19] for a detailed description).
"In order to further corroborate the frequent allegations of torture I've also added, a forensic study, which was conducted by an organisation in the UK that treats torture victims, called Freedom from Torture".
A third study, which was conducted among hemodialysis outpatients, reported an inverse association between hCAP18 levels and 1-year infection-related mortality [ 24].
