Each paper was reviewed in depth. A spreadsheet was used
to develop a combined methodology and theme matrix
(Davies, 1998). These can be seen in Tables 4 and 5. Initially
each column heading described an area from the methodology
and design intended for critical analysis. Each row
contained the details of an individual study reviewed. The
key themes from the first paper reviewed gave rise to new
column headings. As each paper was reviewed new column
headings were added as novel themes were identified. This
process allowed identification of similarities and differences
in the process of combining results across the studies. Some
theme descriptors in the matrix were adapted and expanded
or focussed more clearly through the process. The result of
this was a synthesis across all the studies. This process gave
rise to explicit themes. Put simply this was a synthesis of
themes and categories identified by the original researchers
and often appearing as headings in the research reports.