Fig 1.
Citation network mapping the citations from reviews to RCTs testing dietary fat modification in the secondary prevention of CHD (n = 66; m = 121).
Citation network graph with four RCTs connected to 62 citing reviews by a total of 121 citations. Each vertex represents a paper and the integer label corresponds to a paper in this paper’s bibliography. The colour of a vertex corresponds to a study’s classification (blue is supportive, green is neutral, and red is unsupportive). Vertex size is proportional to in-degree (total number of incoming citations). Each edge corresponds to a specific citation link and the direction of the edge is established by the direction of the arrow head. Visualised with Gephi’s ‘Force Atlas 2’ algorithm [109].
Fig 2.
Sub-graph mapping the citations from neutral reviews to RCTs testing cholesterol lowering diets in the secondary prevention of CHD (n = 21; m = 46).
This graph is composed of four RCTs connected to 17 citing reviews by a total of 46 citations. Each vertex represents a paper and the integer label corresponds to a paper in this paper’s bibliography. The colour of a vertex corresponds to a study’s classification (blue is supportive, green is neutral, and red is unsupportive). Vertex size is proportional to in-degree (total number of incoming citations). Each edge corresponds to a specific citation link, the direction of the edge is established by the direction of the arrow head, and the colour of an edge indicates the classification of the cited article. This was visualised manually in Gephi [108] by lining up reviews in the centre, placing supportive the RCT below and the unsupportive RCTs on top.
Fig 3.
Sub-graph mapping the citations from unsupportive reviews to RCTs testing cholesterol lowering diets in the secondary prevention of CHD (n = 21; m = 38).
This graph is composed of four RCTs connected to 17 reviews by a total of 38 citations. Each vertex represents a paper and the integer label corresponds to a paper in the reference list. The colour of a vertex corresponds to a study’s classification (blue is supportive and red is unsupportive). Vertex size is proportional to in-degree (total number of incoming citations). Each edge corresponds to a specific citation link, the direction of the edge is established by the direction of the arrow head, and the colour of an edge indicates the classification of the cited article.
Fig 4.
Sub-graph mapping the citations from supportive reviews to RCTs testing cholesterol lowering diets in the secondary prevention of CHD (n = 32; m = 37).
This graph is composed of four RCTs connected to 28 citing reviews by a total of 37 citations. Each vertex represents a paper and the integer label corresponds to a paper in the reference list. The colour of a vertex corresponds to a study’s classification (blue is supportive and red is unsupportive). Vertex size is proportional to in-degree (total number of incoming citations). Each edge corresponds to a specific citation link, the direction of the edge is established by the direction of the arrow head, and the colour of an edge indicates the classification of the cited article.
Table 1.
Contingency table of the distribution of citations from three different classifications of review to four secondary prevention RCTs.