Institute of Medicine (US) Committee on the Work Environment for Nurses and Patient Safety; Page A, editor. Keeping Patients Safe: Transforming the Work Environment of Nurses. Washington (DC): National Academies Press (US); 2004. 7, Creating and Sustaining a Culture of Safety. Available from: https://www.ncbi.nlm.nih.gov/books/NBK216181/
A challenging statement in this chapter is that many healthcare workers believe in healthcare "perfection"; that is, every error is punishable. This leads to an atmosphere of blame and fear. Under-reporting is a symptom of a blaming environment, rather than the "just culture" that we all desire where errors are de-identified, analyzed, and provide lessons for the future. It goes on to state that studying "near misses" is almost better than studying actual errors; the potential for harm is still there but there is less shame and blame if it is known that no harm got to the patient. since this is a 10-year old text, you may find topics to validate in today's more sensitive environment. good luck.
You could do an assessment with a tool that has been developed and used with medical students (the APSQ-III), reported by Carruthers et al. in 2009 - also visible on research gate. (Carruthers, S., Lawton, R., Sandars, J., Howe, A., & Perry, M. (2009). Attitudes to patient safety amongst medical students and tutors: Developing a reliable and valid measure. Medical teacher, 31(8), e370-e376. and a second reference: Leung, G., Ang, S., Lau, T. C., Neo, H. J., Patil, N. G., & Ti, L. K. (2013). Patient safety culture among medical students in Singapore and Hong Kong. Singapore Med J, 54(9), 501-505.)
This has to be adapted for use in healthcare professionals but gives an insight into the understanding of medical errors.
Secondly, you could assess the experience of healthcare professionals and their assessment of actual patient safety practice with the SAQ, used in the following references:
Abu-El-Noor, N. I., Hamdan, M. A., Abu-El-Noor, M. K., Radwan, A.-K. S., & Alshaer, A. A. (2017). Safety Culture in Neonatal Intensive Care Units in the Gaza Strip, Palestine: A Need for Policy Change. Journal of pediatric nursing, 33, 76-82. and :
Hamdan, M. (2013). Measuring safety culture in Palestinian neonatal intensive care units using the Safety Attitudes Questionnaire. Journal of critical care, 28(5), 886. e887-886. e814. )
Firstly, I would try a definition of "patient safety gap" as the difference between the best performance in some organizations ie. accredited hospitals and that of other hospitals under study with respect to the implementation of certain evidence based practices in patient safety.
Secondly, depending upon the research objectives I would choose a specific tool to assess this gap.
No actually the HSOPSC also looks good and a lot of experience is around with it. I have not used it yet, but have only used the other questionnaires. I like the APSQ-III (which was designed for students) as it assesses attitudes and I have used it in a student sample before.
Basically, the HSOPSC seems a good tool and if you look at the reported experience and it answers the questions you are interested in, it is a useful and good tool.