"supplementary studies" is correct and usable in written English.
This phrase is typically used to describe additional or extra studies that must be completed in order to gain extra qualifications or knowledge. For example, "After completing the basic requirements of the course, I enrolled in supplementary studies to gain a deeper understanding of the subject."
Last year Genentech argued that the decrease in progression-free survival in its supplementary studies was not due to the pairing of Avastin with drugs other than Taxol.
For the heating sector, these data were derived from nationwide data and supplementary studies.
Some analyses required extra data; therefore, two supplementary studies were conducted.
However, it is evident that appropriate revisions of standards are needed, and supplementary studies by independent researchers should be encouraged.
In addition to the CBA, in some areas supplementary studies have to be prepared, analyzing effects which are difficult to valuate (e.g. some environmental aspects).
In accordance with that, we found in supplementary studies that the effect was of minor importance for [N-methyl-11C]mirtazapine, being less than 3%.
One group had all its supplementary study materials, in English, history and science courses, reset in an unusual font, like Monotype Corsiva.
In this paper, we perform a supplementary study on ENRBF with several properly designed experiments and some further theoretical discussions.
A supplementary study of the electrochemical impedance supports the enhancement of the charge transfer of TiO2 (e−) with the ETPA3 dye.
The herein presented research constitutes a supplementary study in earlier researches for the seismic risk assessment (Baltzopoulou et al. 2012; Eleftheriadou et al. 2014).
Supplementary study of the electrochemical impedance are in support of enhancing charge transfer of TiO2 (e−) with the co-sensitized dyes.
