"subjective characteristics" is a correct and usable phrase in written English.
It typically refers to qualities that are difficult to measure in an objective way, such as a person's preferences or opinions. For example, "People often disagree on the subjective characteristics of a good book."
These subjective characteristics were assessed and scored by the investigator and the subjects themselves every other week (on Days 14, 28, 42, 56, and 70).
"Subjective characteristics, what people think and feel, was just as important in deciding how people vote as any of those objective characteristics – your age, your income, where you live, all of that".
However, very little is currently known about the subjective characteristics of human music perception.
Further, there are studies which simultaneously considered objective and subjective characteristics of the built environment [46, 47].
However, the incorporation of both quantitative and qualitative aspects (requirement 4), does implicitly demand subjective characteristics, for qualitative assessment methods demand subjective evaluation and understanding.
The BMA dataset contains household, physical activity and lifestyle, individual's subjective characteristics, time-use and activity diary, and subjective well-being data.
Loudness is a subjective characteristic of a sound (as opposed to the sound-pressure level in decibels, which is objective and directly measurable).
In [16], complexity has been considered as a subjective characteristic that is represented by a fuzzy interpretation of edges in an image.
The aim of this study was to assess subjective sleep characteristics in patients with type 1 diabetes, to relate sleep characteristics to long-term glycaemic control and to assess possible risk factors for impaired sleep.
Van Dijk et al. (33) used questionnaires to assess subjective sleep characteristics of patients with type 1 diabetes compared with control subjects without diabetes.
The assessment of subjective tinnitus characteristics relies entirely on self-reported experiences and perceptions from the patient.
