BMC Medical Research Methodology 2008, 8:45
http://www.biomedcentral.com/1471-2288/8/45
There were eight relevant qualitative studies examining
children's views of healthy eating. We entered the verba-
tim findings of these studies into our database. Three
reviewers then independently coded each line of text
according to its meaning and content. Figure 1 illustrates
this line-by-line coding using our specialist reviewing soft-
ware, EPPI-Reviewer, which includes a component
designed to support thematic synthesis. The text which
was taken from the report of the primary study is on the
left and codes were created inductively to capture the
meaning and content of each sentence. Codes could be
structured, either in a tree form (as shown in the figure) or
as 'free' codes - without a hierarchical structure.
The use of line-by-line coding enabled us to undertake
what has been described as one of the key tasks in the syn-
thesis of qualitative research: the translation of concepts
from one study to another [32,55]. However, this process
may not be regarded as a simple one of translation. As we
coded each new study we added to our 'bank' of codes and
developed new ones when necessary. As well as translat-
ing concepts between studies, we had already begun the
process of synthesis (For another account of this process,
see Doyle [[39], p331]). Every sentence had at least one
code applied, and most were categorised using several
codes (e.g. 'children prefer fruit to vegetables' or 'why eat
healthily?'). Before completing this stage of the synthesis,
we also examined all the text which had a given code
applied to check consistency of interpretation and to see
whether additional levels of coding were needed. (In
grounded theory this is termed 'axial' coding; see Fisher
[55] for further discussion of the application of axial cod-
Figurel 1 e coding in EPPI-Reviewer
line-by-line coding in EPPI-Reviewer.
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