The phrase "as test group" is not correct in standard written English.
It should be "as a test group" to be grammatically accurate.
Example: "We conducted the experiment with participants selected as a test group to evaluate the new product's effectiveness."
Alternatives: "as a control group" or "as a study group".
In the present study, bone cell activity on 2 implant surfaces with similar microtopography but distinct chemistry and nanotopography (sandblasted/acid-etched surface as control group, and calcium phosphate (CaP) low impregnated surface (Ossean) as test group, both from Intra-Lock, Boca Raton, FL) were evaluated.
Based on this criterion, a total of 36 patients at high risk for IA (including 9 proven cases, 27 probable cases) were served as test group and 50 patients not achieving an EORTC/MSG diagnosis criterion were served as control group.
We used as test group European butterflies that are classic study organisms in spatial ecology.
Transcriptomes of WS18-Pob21-11 and were were served as test group and control.
Serum samples collected from 14 patients diagnosed as RB were used as test group.
as test groups for 7 consecutive days.
See Securities and Exchange Commission, SEC Proposes Transaction Fee Pilot for NMS Stocks (March 14 , 2018 ("The proposed pilot includes a test group that would prohibit rebates and linked pricing, as well as test groups that would impose caps of $0.0015 and $0.0005 for removing or providing displayed liquidity".).
Thirty minutes later, the extract (50, 100, and 200 mg/kg, p.o). was used as test groups.
Two groups ("Grand Bassin": 46 individuals; "Petit Bassin": 57 individuals) out of the three served as test groups.
Solutions A and B were evaluated as test groups following the previous concentrations, with and without pH neutralization.
Groups-III, -IV and -V received three different doses (125, 250 and 500 mg/kg) of test extract and served as test groups.
