'feel difficulties' is a correct and usable part of a sentence in written English.
You can use it to express the idea that someone is having difficulty with something. For example: "My employees have been feeling difficulties with the new system."
Similarly, since face to face intubation with video laryngoscope differs from conventional intubation, untrained practitioner may feel difficulty performing it.
The experts, in spite of being highly skilled in solving problems in their field, often feel difficulty in stating their knowledge in an orderly and logical manner or sometimes even in understanding their own decision making processes.
They felt difficulties to know how to ask and if they identified violence they mostly offered the women a doctor's appointment.
Additionally, all four individual items achieved statistical significance in regards to increased perceived stress between MS-1 and MS-3 year, specifically "I felt unable to control the important things in my life;" "I felt confident in my ability to handle personal problems;" "I felt things were going my way;" and "I felt difficulties were piling up so high I could not overcome them".
Each PSS item assesses the frequency with which respondents felt overwhelmed or able to cope in the past month, e.g. "how often have you felt difficulties were piling up so high that you could not overcome them?" (never to very often, on a 5-point scale).
Two items loaded onto factor 2 'stress control': 'In the last month, how often have you felt that you were unable to control the important things in your life?' (0.719); 'In the last month, how often have you felt difficulties were piling up so high that you could not overcome them?' (0.782).
After reviewing available tools to assess stress the group identified the question "In the last month, how often have you felt difficulties were piling up so high that you could not overcome them?" on the Perceived Stress Scale [ 32, 33] as most suitable to use as a model for the MSWBI question assessing stress.
SBD was assessed by the question "Have you ever felt difficulty breathing during sleep or has anyone in your family told you that you have such difficulty?" SBD was defined as presence of symptoms more than once a month.
