What major factors influence research results? use a specific research project to illustrate.

The theoretical and research frameworks posed a number of different research questions best addressed using a range of methods at a number of levels of enquiry. This was a complex study which integrated qualitative and quantitative methods and involved three stages, followed by a period of data synthesis. The study lasted 21 months (from July 2011 to March 2013).
Stage I consisted of mapping the systems and structural changes within each hospital site (related to research question 1).
Stage II (the main stage) was related to research question 2, and comprised a range of methods, including interviews, surveys and observation.
Stage III involved synthesis of the data, including synthesis with the literature on other vulnerable patient groups. In addition, structured feedback was gathered from clinical and patient safety leads in other vulnerable patient groups, to assess generalisability (research question 3).

Ibelieve the answers are a and c.